SPECIFICATION
"Combine and Threshing Apparatus Mountable Thereon"
Technical Field
[0001] The present invention relates to a combine and a threshing apparatus
mountable thereon.
Background Art
[0002] [1] From Patent Document 1. there is known a combine wherein a power transmission case mounts therein a case input shaft receiving drive force from an engine and a threshing drum output shaft oriented along a fore/aft direction and

drive force from the case input shaft to a threshing drum and this power transmission
case is provided on the front side of a threshing device.
[0003] The combine disclosed in Patent Document 1 includes a gear case
(corresponding to "a power transmission case") attached to the front face of the
threshing device. This gear case includes an input shaft projecting to the left side
therefrom, and a gear speed changing mechanism and the bevel gear mechanism
which are housed in the gear case.
[0004] The input shaft is operably coupled to an engine output shaft via a first
output shaft of a counter case, a first counter shaft and a belt transmission mechanism.
The gear case changes speed of the drive force of the input shaft by the gear speed
changing mechanism and then changes the direction of the force and transmits the
resultant force to the threshing drum (for the above, see paragraphs [0021], [0022]
and Figs. 1-4 of Patent Document 1).
[0005] Another combine is known from Patent Document 2, which includes a power
transmission mechanism capable of forward driving and reverse driving a harvesting
section.
[0006] Patent Document 2 describes three kinds of power transmission mechanisms
as follows.
[0007] The first power transmission mechanism transmits drive force of the engine
output shaft to an input shaft of a counter case and transmits drive force of a
harvesting output shaft of this counter case to a harvesting input shaft of a harvesting
section, and includes a power switchover mechanism mounted within the counter
case.

[0008] The power switchover mechanism includes a gear mounted on a harvesting transmission shaft for transmitting the drive force of the input shaft to the harvesting output shaft and a reverse rotation gear, and a slide gear slidably mounted on the harvesting output shaft. With this power switchover mechanism, when the gear and the slide gear for the harvesting transmission shaft are meshed with each other, the force in the forward rotation direction is transmitted to the harvesting input shaft; and when the sliding gear is meshed with an intermediate gear meshed with the reverse rotation gear of the harvesting transmission shaft, force in the reverse rotation direction is transmitted to the harvesting input shaft.
[0009] The second power transmission mechanism transmits the drive force of the engine output shaft to an input shaft of a threshing device side power transmission case via a drive shaft with a universal joint and transmits drive force of an output
harvesting output shaft mounted in the threshing device side power transmission case and an implement output shaft projecting from the traveling power transmission case. [0010] The harvesting output shaft of the threshing device side power transmission case transmits power to the harvesting input shaft of the harvesting section via a one-way clutch and a harvesting forward rotation clutch. The implement output shaft of the traveling power transmission case transmits power to the harvesting input shaft via a harvesting reverse rotation clutch.
[0011] When the harvesting forward rotation clutch is engaged, forward rotation force is transmitted to the harvesting input shaft. When the harvesting reverse clutch is engaged, reverse rotation force is transmitted to the harvesting input shaft. [0012] The third power transmission mechanism transmits the drive force of the engine output shaft to the input shaft of the threshing device side power transmission case via a drive shaft with a universal joint. The drive force of this harvesting output shaft of this threshing device side power transmission case is transmitted, via a belt, a one-way clutch and a harvesting forward rotation clutch, to the harvesting input shaft of the harvesting section and the drive force of this harvesting input shaft is transmitted to two harvesting shafts via a power switchover mechanism. [0013] The power switchover mechanism includes a forward rotation bevel gear and a reverse rotation bevel gear which are rotatably mounted on the harvesting input shaft, and includes a bevel gear fixed on the harvesting input shaft as being meshed with the forward rotation bevel gear and the reverse rotation bevel gear, and a slider member splined on the harvesting input shaft. In operation of this power switchover mechanism, when the slider member is engaged into a groove portion of

the forward rotation bevel gear, forward rotation drive force is transmitted to the two harvesting shafts. When slider member is engaged into a groove portion of the reverse rotation bevel gear, reverse rotation drive force is transmitted to the two harvesting shafts (for the above, see paragraphs [0016]-[0023], [0028], [0029], [0033], [0035], [0036] and Figs. 4, 6 and 8 of Patent Document 2). [0014] [2] Further, the combined described in Patent Document 2 includes a forward rotation clutch for transmitting forward rotation drive force to the harvesting section and a reverse rotation clutch for transmitting reverse rotation drive force to the harvesting rotation clutch. When the forward rotation clutch is engaged, the harvesting section is driven in forward rotation direction to effect a work. Even if a culm jamming has occurred in the harvesting section, this jaming can be easily solved by reverse driving the harvesting section by switching the reverse rotation clutch into
its engaged conditioru
[0015] This combine includes a threshing side power transmission case having an
input shaft operably coupled via a drive shaft to the engine output shaft, and a
traveling power transmission case having an HST connected to an output shaft of this
threshing side power transmission case via a pulley, a belt, and an input shaft.
[0016] The threshing side power transmission case mounts a harvesting output shaft
projecting therefrom. This harvesting output shaft transmits force to the harvesting
input shaft via a one-way clutch, an output pulley, a harvesting forward rotation
clutch and a forward rotation pulley.
[0017] The traveling power transmission case mounts an implement output shaft
projecting therefrom. This implement output shaft mounts the output pulley via the
one-way clutch and fixedly mounts a reverse rotation input pulley. This reverse
rotation input pulley is operably connected via a belt to a reverse rotation output
pulley fixedly mounted on the harvesting input shaft. For this belt, there is provided
a harvesting reverse rotation clutch.
[0018] With the combine described in Patent Document 2, there is provided one
harvesting clutch lever. In response to an operation on this harvesting clutch lever,
the harvesting forward rotation clutch is engaged to transmit forward rotation force
to the harvesting section, or the harvesting reverse rotation clutch is engaged to
transmit reverse rotation force to the harvesting section.
[0019] More particularly, the harvesting clutch lever is supported to be pivotable
to the right or left and to the forward or rearward between a forward rotation link
member and a revere rotation link member. If the harvesting clutch lever is tilted via
the intercormecting groove in a lever guide toward the forward rotation side to come

into engagement with a groove of the forward rotation link member and slidably operated to the forward side via a forward rotation groove of the lever guide, the forward rotation link member is pivoted so that an attaching portion thereof is moved upward to pull a forward rotation clutch wire connected to this attaching portion, whereby the harvesting forward rotation clutch is engaged.
[0020] On the other hand, if the harvesting clutch lever is tilted via the intercoimecting groove in the lever guide toward the reverse rotation side to come into engagement with a groove of the reverse rotation link member and slidably operated to the forward side via a reverse rotation groove of the lever guide, the, the reverse rotation link member is pivoted so that an attaching portion thereof is moved upward to pull a reverse rotation clutch wire connected to this attaching portion, whereby the harvesting reverse rotation clutch is engaged (for the above, see
[0021] [3] Further, as a threshing apparatus mounted on such combine as described above, there is known an apparatus comprising a threshing drum rotatably driven about a support shaft thereby to effect a threshing operation to harvested crop culms fed into its threshing chamber, with the threshing drum having a cylindrical straight drum portion carrying spiral threshing teeth on the outer periphery of the drum (see e.g. Patent Document 3).
[0022] Further, there is also known an apparatus whose threshing drum comprises a cylindrical drum body and a plurality of threshing teeth or the like formed in V-shaped curves on the outer periphery of the drum body (see e.g. Patent Document
4).
Patent Document 1: Japanese Patent Application "Kokai" No. 11-265670
(JP11-266670A)
Patent Document 2: Japanese Patent Application "Kokai" No. 2004-121123
(JP2004-121123A)
Patent Document 3: Japanese Patent Application "Kokai" No. 11-266666
(JP11-266666A)
Patent Document 4: Japanese Patent Application "Kokai" No. 2006-67910
(JP2006-067910A)
Disclosure of the Invention
[0023] [Problems To Be Solved by Invention]
[1] The problems with the background art [1] are as follows.

In the event of occurrence of jamming in the harvesting section of a combine, if the harvesting section can be driven to rotate in the rotational direction reverse to the forward rotational direction at the time of its operation, the jamming can be easily solved.
[0024] In case the conventional technique of allowing reverse rotation of the harvesting section, this requires either that the entire forward/reverse switchover mechanism be mounted in the power transmission case or on the harvesting input shaft or that a reverse transmission mechanism be provided for taking off reverse drive force from the traveling transmission line and transmitting this force to the harvesting input shaft. The result would tend to invite increase in the costs of the manufacture and mounting of the forward/reverse switchover mechanism and the reverse rotation transmission mechanism. Also, the construction of the transmission

[0025] A further object of the present invention is to provide a combine which
allows the forward/reverse rotational drive of the harvesting section inexpensively
and with simple construction.
[0026] [2] The problems with the background art [2] are as follows.
If the above-described conventional technique is employed for enabling forward/reverse rotational drive of the harvesting section through switchover of a forward rotation clutch and a reverse rotation clutch, this requires provision of a coupling switchover mechanism for switching over between a condition for operably coupling a clutch operating tool with the forward rotation clutch and a condition for operably coupling the clutch operating tool with the reverse rotation clutch, thus requiring a coupling mechanism having a complicated construction for operably coupling the clutch operating tool with the clutches.
[0027] The object of the present invention is to provide a combine which allows forward/reverse rotational drives of the harvesting section with preventing both the forward rotation clutch and the reverse rotation clutch from being engaged at one time, with a simple construction for operable coupling between the clutches and the clutch operating tool. [0028] [3] The problems with the background art [3] are as follows.
With the above-described construction, most of the threshing chamber is used as a space for disposing the threshing drum, so that only a limited space around the threshing drum would remain available for threshing operation. Therefore, when a large amount of harvested culm is fed as material to be threshed into the threshing chamber at the time of e.g. a high-speed operation, this threshing space

may be saturated and with occurrence of such saturation, the threshing material would dwell in the threshing space. As a result, there can occur such inconvenience that the material, without being processed sufficiently, would leak down through the receiving mesh or that the load required for the threshing operation would increase.lo invite damage to the transmission line for the threshing drum. [0029] A still further object of the present invention is to provide a threshing apparatus having a threshing drum construction with distinguished processing capability which can provide sufficient threshing operation to threshing material, without inviting increase in the load required for the threshing operation, even when a large amount of threshing material is supplied thereto. [0030] [Means To Solve Problems] [1] Means to solve the problem [1] are as follows.
engine mounted on a traveling vehicle body; and a harvesting section provided at a front portion of the threshing apparatus,
wherein on the front side of the threshing apparatus, there is provided a power transmission case which mounts a case input shaft for receiving a drive force from the engine, and a fore/aft oriented threshing drum output shaft operably coupled with the case input shaft via a bevel gear mechanism;
said power transmission case further mounts a harvesting output shaft operably coupled with the case input shaft via the bevel gear mechanism so as to be driven in a rotational direction reverse to a rotational direction of the case input shaft;
there is provided a forward rotation clutch for operably coupling one of said case input shaft and said harvesting output shaft with said harvesting input shaft so as to transmit drive force in the forward rotational direction to a harvesting input shaft of the harvesting section; and
there is provided a reverse rotation clutch for operably coupling the other of said case input shaft and said harvesting output shaft with said harvesting input shaft so as to transmit drive force in the reverse rotational direction to the harvesting input shaft of the harvesting section.
[0031] With this construction, when the forward rotation clutch is operated to the engaged condition and the reverse rotation clutch is operated to the disengaged condition, the drive force of either one of the case input shaft and harvesting output shaft operably coupled with the forward rotation clutch is transmitted to the harvesting input shaft. Then, as the rotational direction of the case input shaft and the rotational direction of the harvesting output shaft are opposite to each other.

because of the bevel gear mechanism, the harvesting input shaft is driven in the forward direction.
[0032] On the other hand, when the forward rotation clutch is operated to the disengaged condition and the reverse rotation clutch is operated to the engaged condition, the drive force of either one of the case input shaft and harvesting output shaft operably coupled with the reverse rotation clutch is transmitted to the harvesting input shaft. Then, as the rotational direction of the case input shaft and the rotational direction of the harvesting output shaft are opposite to each other, because of the bevel gear mechanism, the harvesting input shaft is driven in the reverse direction.
[0033] With the above, even if jamming has occurred in the harvesting section, this jamming can be easily solved by driving the harvesting section in the reverse

bevel gear mechanism as a rotational drive switchover means, and the transmission
apparatus as a whole can be simple in its construction and extremely light.
[0034] According to one preferred embodiment, said case input shaft and said
harvesting output shaft are juxtaposed along the transverse direction of the traveling
vehicle body across said threshing drum output shaft.
[0035] With this construction, the case input shaft and the harvesting output shaft
are juxtaposed straight or nearly straight in the transverse direction of the traveling
vehicle body, so that the size of the power transmission case as viewed from the
lateral face of the traveling vehicle body can be as small as possible.
[0036] Accordingly, the construction which allows easy solution of jamming
through reverse rotational drive of the harvesting section can be obtained with the
power transmission case being simply arranged in a compact maimer on the front side
of the threshing apparatus.
[0037] According to one preferred embodiment, said reverse rotation clutch is
maintained under the engaged condition by a manual operation.
[0038] With this construction, the construction which allows easy solution of
jamming through reverse rotational drive of the harvesting section can be obtained
with easily avoiding the occurrence of the trouble due to reverse rotational drive of
the harvesting section.
[0039] That is, when the harvesting section is driven in the reverse rotational
direction for an extended period of time, this can apply an excessive force to the
device of the harvesting section. According to the construction of the third
invention, maintaining of the engaged condition of the reverse rotation clutch needs

to be done manually. Because of this, when the harvesting section is driven in the
reverse rotational direction, the operator can easily take notice so as not to allow the
reverse drive of the harvesting section to last too long, by e.g. effecting the
switchover of the reverse rotational clutch to the engaged direction in an intermittent
manner.
[0040] [2] Means to solve the problem [2] are as follows.
A combine including a threshing apparatus having a threshing drum; an engine mounted on a traveling vehicle body; and a harvesting section provided at a front portion of the threshing apparatus, comprising:
a forward rotation clutch for transmitting a forward rotational drive force to the harvesting section;
a reverse rotation clutch for transmitting a reverse rotational drive force to
a forward rotation clutch operating tool for switching over the forward rotation clutch;
a reverse rotation clutch operating tool for switching over the reverse rotation clutch;
said forward rotation clutch and said reverse rotation clutch being provided separately of one another; and
a restraining mechanism which is switched over into an active condition for restraining switchover of the reverse rotation clutch to the engaged condition, when the forward rotation clutch is under the engaged condition and which is switched over into a releasing condition for releasing the restraint when the forward rotation clutch is under the disengaged condition.
[0041] With this construction, even if an operator tries to switchover the reverse rotation clutch into the engaged condition while the forward rotation clutch is kept under the engaged condition, the restraining mechanism prevents the reverse rotation clutch from being switched over to the engaged clutch. Hence, even when the forward rotation clutch operating tool for switching over the forward rotation clutch and the reverse rotation clutch operating tool for switching over the reverse rotation clutch are provided separately of each other, the reverse rotation clutch cannot be operated into the engaged condition, with the forward rotation clutch being kept under the engaged condition. With this, the forward rotation clutch and the forward rotation clutch operating tool as an operating tool therefor can be operably coupled with each other constantly. And, the reverse rotation clutch and the reverse rotation clutch operating tool as an operating tool therefor can be operably coupled

with each other constantly.
[0042] Accordingly, the construction, which allows forward/reverse rotational
drives of the harvesting section with preventing switchover of the reverse rotation
clutch into the engaged condition while the forward rotation clutch is kept under the
engaged condition, can be formed simply and inexpensively, with keeping the
operating tools operably coupled with the forward rotation clutch as well as the
reverse rotation clutch.
[0043] According to one preferred embodiment, said restraining mechanism is
configured such that the switchover of the reverse rotation clutch into the engaged
condition is restrained as a restraining member supported to one of the forward
rotation clutch operating tool and the reverse rotation clutch operating tool to be
pivotable therewith comes into contact with a contacting portion provided in the
operating tool, thereby to restrict the switchover of the reverse rotation clutch to the
engaged condition.
[0044] With this construction, the restraining mechanism can be obtained with
such simple construction of supporting a restraining member to one of the forward
rotation clutch operating tool and the reverse rotation clutch operating tool to be
pivotable in unison therewith, and of providing a contacting portion in the other one
of the forward rotation clutch operating tool and the reverse rotation clutch operating
tool.
[0045] Accordingly, the construction which allows forward/reverse rotational
drives of the harvesting section with preventing switchover of the reverse rotation
clutch into the engaged condition while the forward rotation clutch is kept under the
engaged condition, can be formed simply and inexpensively, in not only the respect
of the operative coupling between the clutches and the operating tools, but also the
respect of the restraining mechanism.
[0046] [3] Means to solve the problem [3] are as follows.
A threshing apparatus to be mounted on a combine, comprising: a threshing drum driven to rotate about a support shaft for effecting a threshing operation on harvested culm fed into a threshing chamber;
wherein said threshing drum includes a plurality of bar-like members juxtaposed with a predetermined spacing therebetween in the peripheral direction of the threshing drum under a posture along the support shaft, support members provided forwardly and rearwardly of the support shaft so as to support the bar-like members, and a plurality of threshing teeth juxtaposed vvith a predetermined spacing

therebetween in the fore/aft direction under a posture projecting from the bar-like members to the outside of the threshing drum.
[0047] With this construction, the threshing drum includes, therein, a space communicated with the threshing chamber to allow introduction of threshing material into this iimer space. Therefore, during its rotational operation, while threshing material present around it and threshing material introduced into the inner space are being stirred, the drum will effect a threshing operation to these threshing materials, with impacting and raking-in actions by the plurality of bar-like members and the threshing teeth.
[0048] That is to say, even when a great amount of harvested culm, as threshing material, is fed into the threshing chamber, the inner space of the threshing drum can be effectively utilized as the treating space for the threshing operation. As a result,
treating space can be avoided. As a result, it is possible to prevent such inconvenience that the material, without being processed sufficiently, would leak down through the receiving mesh or that the load required for the threshing operation would increase to invite damage to the transmission line for the threshing drum. [0049] Moreover, as the plurality of bar-like members are arranged in juxtaposition and with a predetermined spacing therebetween along the fore/aft direction, it is possible to prevent intertwining of long culms with the bar-like members, thus avoiding dwelling of threshing material due to such intertwining. Further, at the time of the rotational operation of the threshing drum, not only the plurality of threshing teeth, but also the plurality of bar-like members forming the drum body portion of the threshing drum function as the threshing treating members for effecting the threshing operation by impacting and raking-in actions on the threshing material. Consequently, the threshing ability can be improved. [0050] In addition to the above construction, if the threshing drum is provided with a partitioning member for partitioning its inner space between the front and rear sides, further advantage as follows is obtained.
[0051] With this characterizing construction, the partitioning member restricts flow of grains threshed by the threshing operation and/or un-threshed culms coming into the inner space of the threshing drum to the downstream side of the threshing process direction. Further, such threshed grains and the un-threshed culms will be guided to the periphery of the threshing drum in association with rotation of the threshing drum. As a result, it is possible to prevent generation of tertiary loss due to discharge of the threshed grains and/or un-threshed culms from the downstream

end in the threshing process direction, as such threshed grains and the un-threshed culms just pass the inner space.of the threshing drum without being treated. [0052] Therefore, even when a large amount of threshing material is fed, a sufficient threshing operation may be provided on this threshing material, without inviting increase in the load required for the threshing operation and generation of tertiary loss can be prevented. Hence, it is possible to improve the threshing performance and the grain collecting efficiency with avoiding damage to the threshing drum transmission line due to increase in the load. Consequently, it becomes possible to provide a threshing drum construction for a threshing apparatus which construction is superior in the durability and the processing ability. [0053] In addition, if there is provided a winnowing fan for generating sorting air flow and arrangement is made such that the sorting air flow from the winnowing fan
is caused to flow toward The partiirdmng^lhemB^ef;" this "constructronr^is^more'
advantageous in the following respect.
[0054] With this characterizing construction, threshing material stopped by the
partitioning member will be sorted by the sorting air flow from the winnowing fan
toward the periphery of the partitioning member (periphery of the threshing drum)
and will flow from the periphery of the partitioning member toward the downstream
side in the threshing process direction. As a result, it becomes possible to avoid the
risk of accumulation of the threshing material immediately before the partitioning
member.
[0055] Accordingly, it is possible to prevent deterioration in the processing
performance due to accumulation of threshing material.
[0056] According to one preferred embodiment, the upper side of the threshing
drum is covered with a top plate and this top plate mounts a plurality of dust sending
valves for sending harvested culms to the downstream in the threshing process
direction in association with rotational drive of the threshing drum.
[0057] With this characterizing construction, in association with rotation of the
threshing drum, the harvested culms supplied to the threshing chamber will be
conveyed, as being subjected to the threshing action by the impacting and raking-in
actions of the plurality of threshing teeth, toward the downstream side of the
threshing process direction and as the culms reach the upper portion of the threshing
chamber, they will be guided toward the downstream side of the threshing process
direction by the plurality of dust sending valves.
[0058] That is to say, as the threshing drum includes a plurality of threshing teeth
for providing sufficient appropriate threshing action due to the impacting and

raking-in actions by the threshing teeth on the threshing material, and at the same time, the threshing material can be conveyed toward the do\vnstream side in the threshing process direction.
[0059] And, if e.g. each threshing-tooth is provided with a guiding portion for guiding the threshing material toward the downstream side in the threshing process direction in association with rotation of the threshing drum, it becomes possible to effect the conveyance of the threshing material toward the downstream side in the threshing process direction more favorably, and if the tooth is provided with a shape dedicated to threshing for impacting and raking-in the threshing material, it becomes possible to obtain more favorable threshing action on the threshing material. [0060] Therefore, by causing the conveyance of the threshing material toward the downstream side in the threshing process direction to be effected mainly by the dust
sending valves, it is possible to provide a threshing coirslructioirforX"whole-cT charging type combine, which construction allows improvement in the threshing performance and the grain collecting efficiency, without impairing the conveying performance of the threshing material toward the downstream side in the threshing process direction.
[0061] If each dust sending valve is formed with such a length to extend between the right and left side edges of the top plate, it is possible to ensure sufficient length for the dust sending valve mounted on the top plate. With this, the conveyance/guidance of the threshing material toward the downstream side in the threshing process direction by the dust sending valves can proceed more effectively. Therefore, it becomes possible to improve the conveyance performance of the threshing material toward the downstream side in the threshing process direction, while improving the threshing performance and the grain collecting efficiency by the plurality of threshing teeth.
[0062] Further, if the top plate is formed with such a curve as to extend substantially along the rotational locus of the leading end of the threshing teeth, the threshing material which has been conveyed to the upper section of the threshing chamber in association with rotation of the threshing drum can be guided smoothly along the top plate and the dust sending valves, toward the downstream side in the threshing process direction. Therefore, it becomes possible to improve the conveyance performance of the threshing material toward the downstream side in the threshing process direction, while improving the threshing performance and the grain collecting efficiency by the plurality of threshing teeth. And, it becomes also possible to avoid damage to the grains due to their collision against the top plate.

[0063] According to one preferred embodiment, at the front end of the threshing drum, there is mounted a spiral blade for raking in and conveying the harvested culms fed and conveyed toward this front end to the rear side in association with rotation of the threshing drum.
[0064] With this characterizing construction, when the spiral blade is significantly worn out through violent contact with the harvested culms for an extended period of time, this worn spiral blade alone can be replaced by a new one. With this, in comparison with a case of mounting the spiral blade to the front end of the threshing drum non-detachably by means of e.g. welding, it is possible to obtain significant reduction in the trouble and cost required for replacement of the spiral blade. Consequently, the worn-out spiral blade can be replaced easily. And, as the replacement of the worn-out spiral blade is facilitated, it becomes possible to avoid
such inconvenience as deterioratTdhlinh[e'TaHh^Hn7conveyiIig"a^ blade on the harvested culms, and the resultant reduction in the threshing capability, which could be invited if the wear-out of spiral blade is left un-attended. [0065] Therefore, through the simple improvement of detachably attaching the spiral blade to the front end of the threshing drum, appropriate measure for wearing of spiral blade can be carried out easily and inexpensively. As a result, it becomes readily possible to avoid deterioration in the threshing performance due to wear-out of the spiral blade.
[0066] In addition to the above construction, a conveyance assisting guide is provided downwardly of the threshing drum in such a manner as to cover the front end of the threshing drum from under, the conveyance assisting guide receiving harvested culm which has been fed and conveyed toward the front end of the threshing drum and assisting the conveyance of the harvested culm by the spiral blade, and at least a portion of the conveyance assisting guide which portion is located on the downstream side in the rotational direction of the threshing drum is configured to be detachably attachable. With this construction, when the conveyance assisting guide is significantly worn out through violent contact with the harvested culms for an extended period of time, this worn conveyance assisting guide alone can be replaced by a new one. With this, in comparison with a case of mounting the conveyance assisting guide to the front end of the threshing drum non-detachably by means of e.g. welding, it is possible to obtain significant reduction in the trouble and cost required for replacement of the conveyance assisting guide. Consequently, the worn-out conveyance assisting guide can be replaced easily. And, as the replacement of the worn-out conveyance assisting guide is facilitated, it

becomes possible to avoid such inconvenience as deterioration in the raking/conveying action by the spiral blade on the harvested culms due to increase in the gap formed between the spiral blade and the conveyance assisting guide, and the resultant reduction in the threshing capability > which could be invited if the wear-out of conveyance assisting guide is left un-attended.
[0067] Incidentally, the harvested culms or the like, which are raked in and conveyed rearwards by the spiral blade in association with rotation of the threshing drum, will be collected in concentration on the downstream side of the conveyance assisting guide in the rotational direction of the threshing drum, as they are affected by the rotation of the threshing drum. For this reason, in the conveyance assisting guide, its portion located on the downstream side in the rotational direction of the threshing drum will come into more violent contact against the harvested culms or
the like, thus being more readily woriTout diieTo such^ontact^
[0068] Then, in view of the above, if the portion of the conveyance assisting guide located on the downstream side in the rotational direction of the threshing drum is configured to be detachably attachable, then, this portion of the conveyance assisting guide located on the downstream side in the rotational direction of the threshing drum alone can be replaced. With this, compared with the case of replacing the entire conveyance assisting guide, the costs required for the replacement can be further reduced.
[0069] Therefore, through the simple improvement of configuring the portion of the conveyance assisting guide located on the downstream side in the rotational direction of the threshing drum to be detachably attachable, appropriate measure for wear-out of the conveyance assisting guide can be taken easily and inexpensively. As a result, it becomes readily possible to avoid the reduction in the threshing performance due to the wear-out of the conveyance assisting guide.
[0070] According to one preferred embodiment, a receiving mesh is disposed so as to cover the threshing drum from under and a top plate is disposed so as to cover the threshing drum from above, and between the receiving mesh and the top plate, there is detachably mounted a join member configured to have a guide face for continuously bridging inner faces of the receiving mesh and the top plate. [0071] With this characterizing construction, when the guide face of the join member is significantly worn out through violent contact with the harvested culms for an extended period of time, this worn join member alone can be replaced by a new one. With this, in comparison with a case of mounting the join member to the receiving mesh or the top plate non-detachably by means of e.g. welding, it is

possible to obtain significant reduction in the trouble and cost required for replacement of the join member. Consequently, the worn-out join member can be replaced easily. And, as the replacement of the worn-out join member is facilitated, it becomes easily possible to avoid such inconvenience as deterioration in the. raking-in/conveying action which would occur, if the worn-out join member is left un-attended, as this member fails to continuously bridge, with its guide face, the inner face of the receiving mesh and the iimer face of the top plate, thus hindering smooth flowing movement of the harvested culms or the like across the receiving mesh and the top plate of the threshing drum.
[0072] Therefore, through the simple improvement of mounting a join member between the receiving mesh and the top plate in a detachably attachable manner, appropriate measure for wear-out of the join member can be taken easily and
inexpensively. As a result, Tt^be^oTO^sTeadily^posTi'breTo^a^vb^iUT^
threshing performance due to the wear-out of the join member.
[0073] Further and other characterizing constructions and the advantageous effects
resulting from such characterizing constructions will become apparent upon reading
the following detailed description with reference to the accompanying drawings.
Brief Description of the Drawings
[0074] [Fig. 1] an overall side view of a combine according to one embodiment of the present invention,
[Fig. 2] an overall plan view of the combine,
[Fig.3] a diagram of a transmission mechanism,
[Fig. 4] a front view showing a power transmission case disposing section and an operating section,
[Fig. 5] a side view of a chain transmission mechanism,
[Fig. 6] a perspective view of the operating section,
[Fig. 7] a side view showing an operational condition of a forward rotation clutch to an engaged position, an operational condition of an accelerator operating tool to a high-speed position, an operational condition of a reverse rotation clutch to a disengaged position, and active conditions of a restraining mechanism and a high-speed reverse rotation restraining mechanism,
[Fig. 8] a side view showing an operational condition of the forward rotation clutch to a disengaged position, an operational condition of the accelerator operating tool to a low-speed position, an operational condition of the reverse

rotation clutch to an engaged position, and releasing conditions of the restraining
mechanism and the high-speed reverse rotation restraining mechanism.
[Fig. 9] (a) a side view showing a chain tension operational condition of a
tension wheel, (b) a side view showing an active c-ondition of a tension limiting
member,
[Fig. 10] a section view of the chain tensioning mechanism,
[Fig. 11] a side view in vertical section of a threshing apparatus,
[Fig. 12] a front view in partial vertically section showing construction of a
front end portion of the threshing apparatus,
[Fig. 13] a front view in vertical section showing a fore/aft intermediate
portion of the threshing apparatus,
[Fig. 14] a plan view of principal portions showing constructions of a
threshing drum and a conveyance as^fsTing^gui^
[Fig. 15] a plan view in section of principal portions showing the construction of the threshing drum,
[Fig. 16] a section view of principal portions showing a mounting construction of a spiral blade,
[Fig. 17] a rear view in vertical section of the threshing drum showing the construction of the threshing drum,
[Fig 18] a plan view in section of the principal portions showing a further construction of the threshing drum,
[Fig. 19] a front view in vertical section of principal portions showing construction of a join member,
[Fig. 20] a plan view in section of principal portions showing the length and layout of a dust sending valve,
[Fig. 21] a plan view of principal portions showing construction of the conveyance assisting guide,
[Fig. 22] a side view in vertical section of principal portions showing construction of the conveyance assisting guide,
[Fig. 23] a perspective view of principal portions showing construction of a receiving mesh, and
[Fig. 24] a perspective view of principal portions showing construction of a chaff sieve.
Best Mode of Embodying the Invention

[0075] Next, embodiments of the present invention will be described with reference to the accompanying drawings.
Incidentally, unless indicated otherwise, in the following explanation, the direction along which-the traveling vehicle body of the combine travels forwardly and rearwardly will be referred to as the fore/aft direction and the horizontal direction normal to this fore/aft direction will be referred to as the right/left direction and the direction perpendicular to the right/left direction will be referred to as the vertical direction, respectively.
[0076] Fig. 1 is an overall side view of a combine relating to an embodiment of the present invention, more particularly, a whole-culm charging type combine. Fig. 2 is an overall plan view of the combine relating to the embodiment of the present invention. As shown in these figures, the combine relating to the embodiment of the present inveht^To^rTlslieir-pi^elle^d^^by InearTs^of^^
traveling devices 1,1, and includes a self-propelling vehicle body (corresponding to a traveling vehicle body) including a driving section 3 having a driver's seat 2. On the rear side of a vehicle body frame 4 of this self-propelled vehicle body, there are mounted a threshing apparatus 5 and a grain bag charging section 6 disposed side by side along the transverse direction of the self-propelled vehicle body. Further, forwardly of the threshing apparatus 5, there is mounted a harvesting section 10 to which a feeder 11 is connected. This combine is used for harvesting and collecting grains such as rice, wheat, etc and has a construction as follows. [0077] The harvesting section 10 includes, in addition to the feeder 11, a preliminary processing device 13 with a front portion to which a preliminary processing frame 12 is cormected.
[0078] In response to an upper/lower pivotal operation of the threshing apparatus 5 by the feeder 11, the harvesting section 10 is vertically operated between a lowered working condition where a platform 14 disposed downwardly of the preliminary processing frame 12 is lowered to the vicinity of the ground surface and an elevated non-working condition where the platform 14 is elevated high above the ground surface. When the self-propelling vehicle body is caused to travel with the harvesting section 10 being lowered, the preliminary processing device 13 operates such that a pair of right and left dividers 15, 15 disposed at the front portion of the preliminary processing frame 12 divide planted culms to be harvested and planted culms not to be harvested and the planted culms to be harvested are raked in toward the rear side of the preliminary processing frame 12 by means of a rotary reel 17 disposed upwardly of the harvesting apparatus 16 to be harvested by the clipper type

harvesting device 16, then, the harvested culms are conveyed by means of an auger 18 disposed on the upper face side of the platform 14 toward the front side of the feeder 11, then, the harvested culms located at the front side of the feeder 11 are sent to an inlet (not shown) of the feeder 11 by means of a raking rod,l 9 rotatably mounted in the auger 18. Then, the feeder 11, by mean of a feeder conveyer 11 a (see Fig. 3) located therein, conveys the harvested culms fro the raking rod 19 to the rear end portion of the feeder 11 and from a discharge outlet (not shown) provided at this rear end portion, the whole harvested culms from their stock roots to their ear tips, will be supplied to a threshing chamber (not show) of the threshing apparatus 5. [0079] The threshing apparatus 5 operates such that the harvested culms fed to the threshing chamber are threshed by a threshing drum 5a (see Fig. 3) rotatable about an axis along the fore/aft direction of the traveling vehicle body and the resultant
threshed material is sorted mto tEFeshed^^pmns^ahd^wasty^tfaws^a^n^ grains will be fed into a bag charging tank 6a of the grain bag charging section 6. [0080] As shown in Fig. 1 and Fig. 2, the grain bag charging section 6 includes, in addition to the bag charging tank 6a, bag support rods 6c provided under the bag charging tank 6a in correspondence respectively with two gain discharging cylinders 6b juxtaposed along the fore/aft direction of the traveling vehicle body, and a work deck 6d disposed downwardly of the bag support rods 6c and acting also as a bag receiving deck mounted on the vehicle body frame 4, and an auxiliary deck 6e supported to the lateral end of the vehicle body frame 4. The auxiliary deck 6e is supported to be vertically pivotable so as to be switched over between a lowered used posture where the deck projects horizontally to the lateral outer side of the vehicle body from the vehicle body frame 4, and an elevated stored posture where the deck is pivoted upward from this lowered used posture into alignment with the vertical direction of the traveling vehicle body.
[0081] The self-propelled vehicle body includes an engine 20 mounted downwardly of the driver's seat 2. Fig. 3 is a diagram of a transmission mechanism for transmitting the drive force from the engine 20 to the traveling device 1, the threshing apparatus 5 and the harvesting section 10. As shown in this figure, a traveling transmission section of this transmission mechanism transmits the drive force of an output shaft 20a of the engine 20 via a bevel transmission mechanism 21 to an input shaft 22a of a traveling speed changing device 22 and inputs the drive force of an output shaft 22b of this traveling speed changing device 22 to a traveling transmission 23 so that the power is transmitted by this traveling transmission 23 to the pair of right and left traveling devices 1,1.

[0082] The traveling speed changing device 22 is provided continuously from the case of the traveling transmission 23. This traveling speed changing device 22 comprises a variable displacement axial plunger type hydraulic pump including the input shaft 22a acting as a pump shaft; and an axial plunger type hydraulic motor driven by pressure oil from this hydraulic pump. That is to say, this traveling speed changing device 22 is constructed as a hydrostatic stepless speed changing device. [0083] In a work transmission section of the transmission mechanism, the output shaft 20a of the engine 20 is operably connected to one end of a winnowing fan drive shaft 26 of the threshing apparatus 5 via a belt transmission mechanism 25, and the other end of this winnowing fan drive shaft 26 is operably connected via a belt transmission mechanism 27 to a first screw conveyer 28 and a second screw conveyer 29 of the threshing apparatus 5, and a PTO (power takeoff) shaft 30 provided in the
belt transmission mechanism "27"is^peFaHy~coniiectedTo'¥son^ing;Ue^ 32 of the threshing apparatus 5 via a belt transmission mechanism 31. [0084] In the work transmission section of the transmission mechanism, the drive force outputted from the output shaft 20a of the engine 20 is transmitted, via the belt transmission mechanism 25, the winnowing fan drive shaft 26 and a belt transmission mechanism 35 provided at the other end of this winnowing fan drive shaft 26, to a case input shaft 37 of a power transmission case 36, and the drive force of this case input shaft 37 is transmitted via a threshing drum output shaft (corresponding to the support shaft of the threshing drum) 38 of the power transmission case 36 to the threshing drum 5a and the drive force of the case input shaft 37 is transmitted, either via a normal or forward rotation clutch 40 or via a harvesting output shaft 39 of the power transmission case 36 and a reverse rotation clutch 41 to a harvesting input shaft 42 of the harvesting section 10. Referring more particularly to this power transmission, this transmission is constructed as follows.
[0085] That is, as shown in Figs. 2 and 4, the power transmission case 36 is supported to a front wall portion of the threshing apparatus 5, on the front side of the threshing apparatus 5 relative to the traveling vehicle body and upwardly of the rear end of the feeder 11. As shown in Fig. 3, the power transmission case 36 mounts the threshing drum output shaft 38 disposed with rearward orientation relative to the fore/aft direction of the traveling vehicle body at the center portion of the power transmission case 36 in the transverse direction of the traveling vehicle body. The power transmission case 36 mounts the case input shaft 37 and the harvesting output shaft 39 in distribution on the one end side and the other end side of the power transmission case 36 in the transverse direction of the traveling vehicle body and in

juxtaposition across the threshing drum output shaft 38 and further mounts the case input shaft 37 with the transverse orientation relative to the traveling vehicle body. The threshing drum output shaft 38 is operably connected to the rotation support shuft of the threshing drum 5a to be rotatable in unison therewith. [0086] The power transmission case 36 houses therein a bevel gear mechanism 43 having a bevel gear 43 a mounted on an end of the case input shaft 37 to be rotatable in unison therewith. This bevel gear mechanism 43 includes, in addition to the bevel gear 43 a, a bevel gear 43b mounted on an end of the harvesting output shaft 39 to be rotatable in unison therewith, and a bevel gear 43c mounted on the threshing drum output shaft 38 to be rotatable therewith and meshed with the bevel gears 43a and 43b. That is to say, the bevel gear mechanism 43 allows operative coupling between the case input shaft 37 oriented transverse relative to the traveling vehicle body and the thresliing drum output shaft 38 orientedTlong'tEeTore/affllifection otTheTfavelmg" vehicle body and also the operative coupling between the case input shaft 37 and the harvesting output shaft 39 with the rotational direction of the case input shaft 37 and the rotational direction of the harvesting output shaft 39 being opposite to each other. [0087] As shown in Fig. 3 and Fig. 4, the forward rotation clutch 40 is constructed as a belt tension clutch which is switched over between an engaged condition and a disengaged condition when a transmission belt 40a wound around one end sides of the case input shaft 37 and the harvesting output shaft 42 is switched over between a tensed condition and a loosened condition by a tension wheel 40c of a tensioning member 40b. The tensioning member 40b is pivotally supported to an end of the power transmission case 36. The forward rotation clutch 40, when switched over into the engaged condition, transmits the drive force of the case input shaft 37 to the harvesting input shaft 42 as a drive force for driving the harvesting section 10 in the forward rotational direction.
[0088] As shown in Fig. 3 and Fig. 4, the reverse rotation clutch 41 is constructed as a belt tension clutch which is switched over between an engaged condition and a disengaged condition when a transmission belt 41a wound around the other end sides of the harvesting output shaft 39 and the harvesting input shaft 42 is switched over between a tensed condition and a loosened condition by a tension wheel 41c of the tensioning member 41b. The tensioning member 41b is pivotally supported to an end of the power transmission case 36. The reverse rotation clutch 41, when switched over into the engaged condition, transmits the drive force of the harvesting output shaft 39 to the harvesting input shaft 42 as a drive force for driving the harvesting section 10 in the reverse rotational direction.

[0089] As shown in Fig. 3. the harvesting input shaft 42 is constructed as a conveyer drive shaft for driving the feeder conveyer 11 a. The harvesting input shaft 42 is operably coupled to a drive shaft 45 of the harvesting device 16 via a transmission chain 44. This drive shaft 45 and the drive shaft 46 of the auger 18 are operably coupled with each other via a transmission chain 47. The drive shaft 46 of the auger 18 and a drive shaft 48 of the rotary reel 17 are operably coupled with each other via a coupling mechanism using a transmission chain 49 and a transmission belt 50.
[0090] The harvesting input shaft 42, if receiving the drive force in the forward rotational direction, drives the feeder conveyer 11a. the auger 18. the harvesting device 16 and the rotary reel 17 of the harvesting section 10 in the forward rotational direction so as to effect a normal preliminary processing operation and a conveying
operation. The harvesting input shafts4T,Tf receivlnglhe dnve~force"in the reverse" rotational direction, drives the feeder conveyer 11a, the auger 18, the harvesting device 16 and the rotary reel 17 of the harvesting section 10 in the rotational direction reverse to the normal rotational direction for working.
[0091] Fig. 4 shows, in a front view, the constructions of an operating section provided in the driving section 3 for effecting the switchover operations between the forward rotation clutch 40 and the reverse rotation clutch 41, and a speed adjusting operation of the engine 20. Fig. 6 is a perspective view of the operating section. As shown in these figures and in Fig. 2, the operating section includes a control panel 51 provided on a lateral side of the driver's seat 2, a lever type forward rotation clutch operating tool 52 and a lever type accelerator operating tool 53 which are juxtaposed along the transverse direction of the traveling vehicle body, and a lever type reverse clutch operating tool 54 disposed on the lateral outer side opposite to the driver's seat side of the control panel 51.
[0092] The forward rotation clutch operating tool 52 is supported to a support member 56 via a rotational support shaft 55 connected to the base of this operational tool 52 to be rotatable in unison, so that the operating tool 52 is pivotable about the axis of the rotational support shaft 55 which is oriented along the transverse direction of the traveling vehicle body. The support member 56 is attached to the rear face of the control panel 51. This forward rotation clutch operating tool 52 is operably coupled with the tensioning member 40b of the forward rotation clutch 40 via a coupling mechanism 60 including a pivot arm 61 provided at the end of the rotational support shaft 55 opposite to the other end to which the forward rotation clutch operating tool 52 is connected, to be rotatable in unison therewith.

[0093] As shown in Fig. 6 and Fig. 7. the coupling mechanism 60 includes, in addition to the pivot arm 61, a pivot link 63 having one end portion thereof pivotally connected to the free end portion of this pivot arm 61 via a connecting pin 62, and an operational cable 64 which operably couples the other end portion of this pivot link 63 to the tensioning member 40b of the forward rotation clutch 40 via an inner cable. [0094] Fig. 7 shows an operational condition to the engaged position of the forward rotation clutch operating tool 52. As shown in this figure, if the forward rotation clutch operating tool 52 is pivotally operated in the fore/aft direction of the traveling vehicle body along the guide groove 51a (see Fig. 4) of the control panel 50 to the front end of this guide groove 51a. about the transverse axis of the traveling vehicle body of the rotational support shaft 55, the forward clutch operating tool 52 is operated into the engaged position. Then, the forward clutch operating tool 52
pivotally elevates the" pivot ¥fnf"6^1,Thei^b3n;'o^^^^
the inner cable of the operational cable 64 is pulled to pivot the tensioning member 40b so that this member 40b presses the transmission belt 40a, whereby the transmission belt 40a is rendered into the tensioned state, thus realizing the engaged condition of the forward rotation clutch 40.
[0095] Fig. 8 shows an operational condition to the disengaged position of the forward rotation clutch operating tool 52. As shown in this figure, if the forward rotation clutch operating tool 52 is pivotally operated to the rear end of the guide groove 51 a, the forward clutch operating tool 52 is operated into the disengaged position. Then, the forward clutch operating tool 52 pivotally lowers the pivot arm 61, thereby to lower the pivot link 63. With this, the inner cable of the operational cable 64 is loosened to pivot the tensioning member 40b so that this member 40b releases its pressing on the transmission belt 40a, whereby the transmission belt 40a is rendered into the loosened state, thus realizing the disengaged condition of the forward rotation clutch 40.
[0096] As shown in Fig. 4, Fig. 6 and Fig. 7, the reverse rotation clutch operating tool 41 is cormected to the tensioning member 41b of the reverse rotation clutch 41 and is pivotally supported to the end of the power transmission case 36 via this tensioning member 41b.
[0097] Fig. 8 shows an operational condition to the engaged position of the reverse rotation clutch operating tool 41. As shown in this figure, if the reverse rotation clutch operating tool 41 is pivotally elevated about the axis of the harvesting output shaft 39 which axis is oriented along the transverse direction of the traveling vehicle body, the reverse rotation clutch operating tool 41 is operated into the engaged

position. Then, the reverse rotation clutch operating tool 41 pivotally operates the tensioning member 41b to the engaged side, whereby the tensioning roller 41c pulls the transmission belt 41a, thus rendering the reverse rotation clutch 41 into the engaged condition. In this, the reverse rotation clutch 41 keeps its engaged condition, as the reverse rotation clutch operating tool 41 is manually maintained at the engaged position.
[0098] Fig. 7 shows the operational condition to the disengaged position of the reverse rotation clutch operating tool 54. As shown in this figure, if the maintenance of the reverse rotation clutch operating tool 54 to the engaged position, the reverse rotation clutch operating tool 54 will be pivotally lowered naturally to be rendered into the disengaged position. Then, the reverse rotation clutch operating tool 54 will pivotally operate the tensioning member 41b to the disengaged side, whereby the
tensioning roller 41 e releasesTts^uIIing^acTi^hronThFWansmiMi^ the transmission belt 41a is loosened, thus disengaging the reverse rotation clutch 41. [0099] As shown in Fig. 4, the accelerator operating tool 53 is supported to a support member 58 via a support shaft 57 into which the base end portion of the tool is inserted, so that the tool 53 is pivotable about the axis of the support shaft 57 oriented along the transverse direction of the traveling vehicle body. The support member 58 is attached to the rear face of the control panel 51. This accelerator operating tool 53 is operably coupled to an accelerator (not shown) of the engine 20 via an operational cable (not shown) having one end of its inner cable cormected to the base end portion of the accelerator operating tool 53.
[0100] Fig. 7 shows an operational condition to the high-speed position of the accelerator operating tool 53. As shown in this figure, if the accelerator operating tool 53 is pivotally operated along a guide groove 5 lb (see Fig. 4) of the control panel 51 to a position at the rear end of the guide groove 51b, then, the accelerator operating tool 53 is rendered into the high speed position, thus operating the accelerator to the high speed condition. This realizes a high speed condition for work where the engine 20 is rotated at a high rotational speed suitable for a work. [0101] Fig. 8 shows an operational condition to the low-speed position of the accelerator operating tool 53. As shown in this figure, if the accelerator operating tool 53 is operated to the position at the front end of the guide groove 51b, then, the accelerator operating tool 53 is rendered into the high speed position, thus operating the accelerator to the low speed condition. This realizes a non-work low speed condition for work where the engine 20 is rotated at a low rotational speed set for reverse driving of the harvesting section 10.

[0102] As shown in Fig. 4, Fig. 6 and Fig. 7, the operating section includes a restraining mechanism 70 having a restraining member 71 comprised of a band plate member with one end thereof connected to the pivot arm 61, and a high speed reverse rotation restraining mechanism 80 having a high speed reverse rotation restraining member 81 comprised of a bent rod member connected to the accelerator operating tool 53.
[0103] The restraining mechanism 70 includes, in addition to the restraining member 71, a contacting portion 73 comprised of a bent rod 72 extending from the tensioning member 41b toward the upper face side of the control panel 51. [0104] The restraining member 7Hs comprised of a band plate member connected to the pivot arm 61 and is supported to the forward rotation clutch operating tool 52 via the pivot arm 61 and the rotational support shaft 55 to be movable in unison with
the forward rotation clutch operating To01732"^ TE^"cbirtacTih"g^^oTtioir73 "ts^ comprised of the bent rod 72 extending from the tensioning member 41b to which the reverse rotation clutch operating tool 54 is connected. So that, this portion 73 is provided in the reverse rotation clutch operating tool 54 to be movable in unison with the reverse rotation clutch operating tool 54.
[0105] Fig. 7 is a side view showing the restraining mechanism 70 under its active condition As shown in this figure, if the forward rotation clutch operating tool 52 is operated into the engaged position, the restraining member 71 is elevated by the pivot arm 61 to a position level with the disposing position of the control panel 51. Then, the restraining member 71 is rendered into an active position where a restraining operational portion 71a formed by an end of the band plate member enters a moving path of the contacting portion 73. With this, if an attempt is made to switch over the reverse rotation clutch operating tool 54 from the disengaged position to the engaged position, the restraining member 71 prevents movement of the reverse rotation clutch operating tool 54 to the engaged position through the contact between the restraining operational portion 71a and the contacting portion 73.
[0106] Namely, when the forward rotation clutch 40 is under its engaged condition, the restraining mechanism 70 restraints or prevents switchover of the reverse rotation clutch operating tool 54 to the engaged position through its contact with the contacting portion 73 provided in the reverse rotation clutch operating tool 54, thus being rendered in to the active condition for restraining the switchover of the reverse rotation clutch 41 to its engaged condition.
[0107] Fig. 8 is a side view showing the restraining mechanism 70 under its releasing condition. As shown in this figure, if the forward rotation clutch operating

tool 52 is operated into the disengaged position, the restraining member 71 is lowered by the pivot arm 6 i to a position lower than the disposing height of the control panel 51. Then, the restraining member 71 is rendered into the releasing position where the member is retracted away from the moving path of the-^contacting portion 73, thus preventing the contact between the contacting portion 73 and the restraining operational portion 71 a in the course of the switchover of the reverse rotation clutch operating tool 54 from the disengaged position to the engaged position. [0108] That is to say, when the forward rotation clutch 40 is under its disengaged condition, the restraining mechanism 70 releases the restraint of switchover of the reverse rotation clutch operating tool 54 to the engaged position, thus releasing the restraint of the switchover of the reverse rotation clutch 41 to its engaged condition. [0109] The high speed reverse rotation restraining mechanism 80 includes, in
addition to the high speed^^versF rofatioiTfestTaining rnember'8"T7""a~conractinf portion 82 comprised of the bent rod 72.
[0110] The hi gh speed revere rotation restraining member 81, comprised of the bent rod connected to the accelerator operating tool 53, is supported to the accelerator operating tool 53 to be movable in unison with this accelerator operating tool 53. The contacting portion 82 is comprised of the bent rod 72 extending from the tensioning member 41b to which the reverse rotation clutch operating tool 54 is connected In this way, the member 81 is provided in the reverse rotation clutch operating tool 54 to be movable in unison with this reverse rotation clutch operating tool 54. The high speed reverse rotation restraining member 81 includes a restraining operating portion 83 formed of bent portion of the bent rod constituting the same. This high speed reverse rotation restraining member 81 is movably held to a holder 84 supported to the control panel 51, at a portion thereof located between its portion cormected to the accelerator operating tool 53 and the restraining operational portion 83. The holder 84 is supported to the control panel 51. [0111] Fig. 7 is a side view showing the high speed reverse rotation restraining mechanism 80 under its active condition. As shown in this figure, if the accelerator operating tool 53 is operated into its high speed position, the high speed reverse rotation restraining member 81 is moved to the rear side of the traveling vehicle body by the accelerator operating tool 53. Then, the high speed reverse rotation restraining member 81 is rendered into the active position. Whereby, if an attempt is made to switch over the reverse rotation clutch operating tool 54 from the disengaged position to the engaged position, the contact between the restraining operational portion 83 and the contacting portion 82 provides resistance against the above

movement of the reverse rotation clutch operating tool 54 toward the engaged position.
[0112] That is to say, when the engine 20 is under the high speed work condition, the high speed reverse rotation restraining mechanism 80 makes the movement of the reverse rotation clutch operating tool 54 to the engaged position difficult by the contact between the restraining operational portion 83 of the high speed reverse rotation restraining member 81 and the contacting portion 82 provided in the reverse rotation clutch operating tool 54, thereby to restrain or prevent the switchover of the reverse rotation clutch 41 into the engaged condition.
[0113] Fig 8 shows a side view showing the high speed reverse rotation restraining mechanism under its releasing condition. As shown in this figure, if the accelerator operating tool 53 is operated into the low speed position, the high speed reverse r o t ati on re straining lnembePSTTs^d\^ t o^he^front" si d^^ThFTi^^ body by the accelerator operating tool 53. Then, the high speed reverse rotation restraining member 81 is rendered into the releasing position, thus preventing the contact between the restraining operational portion 83 of the high speed reverse rotation restraining member 81 and the contacting portion 82 of the reverse rotation clutch operating tool 54 in the course of the switchover of the reverse rotation clutch operating tool 54 from the disengaged position to the engaged position. [0114] That is to say, when the engine 20 is under the non-work low speed condition, the high speed reverse rotation restraining mechanism 80 is rendered into the releasing condition for releasing the restraint of the switchover of the reverse rotation clutch 41 to the engaged position, thus releasing the switchover of the reverse rotation clutch 41 to the engaged condition.
[0115] Namely, when a work is to be done, the accelerator operating tool 53 is operated into the high speed position and the reverse rotation clutch operating tool 54 is operated into the disengaged position, and the forward rotation clutch operating tool 52 is operated into the engaged position. With these, the engine 20 is rotated at the working high speed condition, so that the drive force from the output shaft 20a of the engine 20 is transmitted via the belt transmission mechanism 25, the winnowing fan drive shaft 26 and the belt transmission mechanism 35 to the case input shaft 37 of the power transmission case 36, whereby this case input shaft 37 is driven and the drive force of this case input shaft 37 is transmitted via the bevel gear mechanism 43 to the harvesting output shaft 39, so that this harvesting output shaft 39 is driven to rotate in the rotational direction reverse to the rotational direction of the case input shaft 37. As the forward rotation clutch 40 is rendered into the engaged condition,

the drive force of the case input shaft 37 is transmitted via the forward rotation clutch 40 to the harvesting input shaft 42 and as the reverse rotation clutch 41 is rendered nto the disengaged condition, the drive force of the harvesting output shaft 39 is not ransmitted to the harvesting input shaft 42, whereby this harvesting input shaft 42 is iriven at the working rotational speed in the forward rotational direction. Then, the irive force of this harvesting input shaft 42 is transmitted directly to the conveying ;nd of the feeder conveyer 11, transmitted via the transmission chain 44 to the drive shaft 45 of the harvesting device 16 and transmitted via the transmission chain 44 and the transmission chain 47 to the drive shaft 46 of the auger 18 and transmitted via the transmission chain 44. the transmission chain 47 and the transmission belt 50 to the drive shaft 48 of the rotary reel 17, respectively. Whereby, the feeder conveyer 11a, the auger 18, the harvesting device 16 and the rotary reel 17 are driven at the
rotational speeds suitable for the worMngm lEeforward rotati"onal direction: [0116] When jamming of harvested culms has occurred in the harvesting section 10, the accelerator operating tool 53 is switched over into the low speed position, the forward rotation clutch operating tool 52 is switched over to the disengaged position, and the reverse rotation clutch operating tool 54 is switched over into the engaged position, respectively. In this, as the accelerator operating tool 53 is switched over to the low speed position, the restraint by the high speed reverse rotation restraining mechanism 80 to restrain the switchover of the reverse rotation clutch 41 is released and as the forward rotation clutch operating tool 52 is switched over to the disengaged position, the restraint by the restraining mechanism 70 to restrain the switchover of the reverse rotation clutch 41 is released. Thereafter, the reverse rotation clutch operating tool 54 is switched over into the engaged position. [0117] Then, the engine 20 is rotated at the non-working low speed condition, whereby the drive force from the output shaft 20a of the engine 20 is transmitted via the belt transmission mechanism 25, the winnowing fan drive shaft 26 and the belt transmission mechanism 35 to the case input shaft 37 of the power transmission case 36, the drive force of this case input shaft 37 is transmitted via the bevel gear mechanism 43 to the harvesting output shaft 39 and this harvesting output shaft 39 is driven in the rotational direction reverse to the rotational direction of the case input shaft 37. As the forward rotation clutch 40 is rendered into the disengaged condition, the drive force of the case input shaft 37 is not transmitted to the harvesting input shaft 42 and as the reverse rotation clutch 41 is rendered into the engaged condition, the drive force of the harvesting output shaft 39 is transmitted via the reverse rotation clutch 41 to the harvesting input shaft 42, whereby this harvesting input shaft 42 is

driven at the non-working low speed in the reverse rotational direction. Then, the drive force of this harvesting input shaft 42 is transmitted directly to the conveying terminal end of the feeder conveyer 11, transmitted via the transmission chain 44 to the drive shaft 46 of the harvesting-^device 16, transmitted via the transmission chain 44 and the transmission chain 47 to the drive shaft 46 of the auger 18 and transmitted via the transmission chain 44, the transmission chain 47 and the transmission belt 50 to the drive shaft 48 of the rotary reel 17, respectively. As a result, the feeder conveyer 11 a, the auger 18, the harvesting device 16 and the rotary reel 17 are driven at rotational speeds appropriate for solving the jamming in the reverse rotational directions, so that the harvested culm jamming can be easily solved. In this, as long as the reverse rotation clutch operating tool 54 is manually kept under its engaged position, the reverse rotation clutch 41 is rendered into the engaged condition to drive
the harvesting" "sectfoiPnrih^h^reverse^irecfi^n^ Then7 iipun^reteasirrg"of^e^ manual maintenance of the reverse rotation clutch operating tool 54 at the engaged position, the reverse rotation clutch operating tool 54 will be naturally or automatically switched over into the disengaged position, so that the reverse rotation clutch 41 is rendered into the disengaged condition, thus stopping the reverse drive of the harvesting section 10.
[0118] Fig. 5 is a side view of a chain transmission mechanism including the transmission chain 44. This chain transmission mechanism includes a guide w^heel 89 around which the transmission chain 44 is wound to be guided, and includes also a chain tensioning mechanism 90 having a tension arm 91 supported to a lateral wall portion lib of the feeder 11.
As shown in Fig. 5 and Fig. 10, the chain tensioning mechanism 90 includes, in addition to the tension arm 91, a spring 92 connected to this tension arm 91. The spring 92 pivotally urges the tension arm 91 about a support shaft 93, whereby a freely rotatable tension wheel 94 of the tension arm 91 is pressed and urged against the transmission chain 44, thereby to apply a tension to this transmission chain 44. [0119] The opposite side of the spring 94 to its side connected to the tension arm 91 is operably connected to a spring support rod 96 supported via a bracket 95 to the lateral wall portion 1 lb of the feeder 11. The tension wheel 94 acts on a portion 44a of the transmission chain 44 which portion 44a is the loosened side at the time of forward rotational drive of the harvesting section 10. The tension arm 91 includes a tension restricting member 97 attached to and between this tension arm 91 and the spring support rod 96. [0120] As shown in Fig. 9 and Fig. 10, the tension restricting member 97 and the

spring support rod 96 are connected to be pivotable relative to each other via a connecting pin 98. The tension restricting member 97 and the tension arm 91 are operably coupled with each other via a support shaft 99 which rotatably supports the tension wheel 94. The support shaft 99 is slidably inserted into a>_restricting elongated hole 100 provided in the tension restricting member 97. [0121] Fig. 9 (a) shows a tension operating condition of the tension wheel 94 when the harvesting section 10 is driven in the forward rotational direction. As shown in this figure, when the harvesting section 10 is driven in the forward rotational direction, the portion 44a of the transmission chain 44 acted on by the tension wheel 94 becomes the loosening side. Then, the tension wheel 94, with the pulling operation by the spring 92, tenses the chain portion 44a.
[0122] Fig. 9 (b) shows the operational condition of the tension restricting member
97 when the harvesting secfioh^rO^Ts^dnN^'ln^h^TeveiWl^afioM^ Tts
shown in this figure, when the harvesting section 10 is driven in the reverse rotational direction, the tension restricting member 97 restricts the movement of the tension wheel 94 against the spring 92. This makes it difficult for the portion 44b which is the loosened side of the transmission chain 44 to be disengaged from the guide wheel 9 in driving the harvesting section 10 in reverse.
[0123] That is to say, if the portion 44a of the transmission chain 44 acted upon by the tension wheel 94 becomes the tensed side, this tension causes the tension wheel 94 to be moved against the spring 92. Then, the tension restricting member 97 supports the tension wheel 94 via the support shaft 99 so as to restrict the movement of the tension wheel 94 against the spring 92. As a result, the tension restricting member 97 restricts the amount of loosening at the portion 44b which becomes the loosening side of the transmission chain 44 in driving the harvesting section 10 in reverse, so as not to allow such a significant loosening to occur as may result in disengagement from the guide wheel 89.
[0124] As shown in Figs. 11-13, in an upper section of the threshing apparatus 5, there is formed a threshing chamber 114. The threshing chamber 114 mounts therein the threshing drum 5a rotatable about the fore/aft oriented threshing drum output shaft (corresponding to the support shaft of the threshing drum) 38 mounted along the conveying direction of the harvested culms. Downwardly of the threshing drum 5a, there is mounted a receiving mesh 117. This receiving mesh 117 has a U-shape as viewed from its front and receives harvested culms to be threshed in association with rotation of the threshing drum 5a and allows the threshed material to be dropped therethrough. In the threshing apparatus 5, rearwardly of the receiving

mesh 117 which is the downstream end in the threshing process direction, there is formed a culm discharging opening 118 for discharging the threshed culms to the outside of the vehicle body. Downwardly of the receiving mesh 117, there is mounted a swinging sorting mechanism 1 l£for effecting a sieving sorting operation on the processing material fallen through the receiving mesh 117. Forwardly and downwardly of the swinging sorting mechanism 119, there is mounted a winnowing fan 120 for feeding sorting air flow to the processed material dropped from the receiving mesh 117 or the material in the course of the sieving sorting process. Rearwardly of the winnowing fan 120, there is formed a primary collecting section 121 for collecting the processed material dropped through the front portion of the swinging sorting mechanism 119. Rearwardly of this primary collecting section 121, there is formed a secondary collecting section 122 for collecting the processed rriMerial dfop'pMThlwigh Ihe fear porttar^^
Rearwardly of the swinging sorting mechanism 119, there is formed a discharge opening 123 for discharging the processed material which has been conveyed to the rear end of the swinging sorting mechanism 119, to the outside of the vehicle body. Upwardly of the threshing drum 5a, there is mounted a top plate 124 for covering the upper side of the threshing drum 5a from above, so that the harvested culms and threshing material which have been conveyed to the upper portion of the threshing drum 5a in association with rotation of the threshing drum 5a may be guided toward the receiving mesh 117.
[0125] The threshing chamber 114 is delimited and sectioned by such components as the receiving mesh 117 and the top plate 124 covering the threshing drum 5a. At a front end lower portion of the threshing chamber 114, there is formed a feeding opening 125 into which the whole harvested culms which have been conveyed by the feeder 11 are fed as processing material.
[0126] The threshing drum 5a is mounted between the front wall 126 and the rear wall 127 of the threshing apparatus 5, with its threshing drum output shaft 38 being rotatable. And, the threshing drum 5a is driven by the power from the engine 20 transmitted via the winnowing fan 120, etc. to rotate clockwise in the front view about the threshing drum output shaft 38. With this rotational drive, threshing operation is effected on the harvested culms charged into the threshing chamber 114, so that the material will be rendered into separated grains and at the same time the harvested culms thereof are conveyed toward the rear side of the vehicle body which is the downstream side in the threshing process direction. [0127] The receiving mesh 117 is a concave receiving mesh in the form of grating.

The receiving mesh 117 receives the harvested culms charged into the threshing chamber 114 and assists the threshing operation by the threshing drum 5a on these harvested culms. More particularly, the receiving mesh 117 receives the harvested culms subje'cted to the threshing operation in association with rotation of the threshing drum 5a and causes separated grains or grains with branches or culm chaffs generated from the threshing operation to drop toward the swinging sorting mechanism 119 disposed downward and at the same time prevents dropping of the threshed culms toward the swinging sorting mechanism 119.
[0128] The swinging sorting mechanism 119 includes a sieve case 129 in the form of a frame as viev/ed from above, the sieve case 129 being driven to swung in the fore/aft direction by a cam type drive mechanism 128. Upwardly of the sieve case 129, there are disposed a rough-sorting grain pan 130, a chaff sieve 131 and a straw
rack 132 in this mentioned order from the front side^^^the sieve case"r29T" Downwardly of the sieve case 129, there are disposed a fine-sorting grain pan 133 and a grain sieve 134 in this mentioned order from the front side of the sieve case 129. Upwardly of the swinging sorting mechanism 119, the sorting processing material dropped from the receiving mesh 117 and containing separated grains and culm chaffs etc. in a mixed state are received by the upper grain pan 130 or the chaff sieve 131 or the straw rack 132, so as to effect a rough sorting operation by a sieving sorting operation. Downwardly of the swinging sorting mechanism 119, the sorting processing material dropped from e.g. the chaff sieve 131 and containing separated grains and grains with branches attached thereto are received by the downwardly provided grain pan 133 and the grain sieve 134, to effect a fine sorting operation by sieve sorting process. As a result, the sorting processing material will be sorted into individual separated grains as the primary products, the mixture containing also the grains with branches attached thereto and culms chaffs in a mixed state as the secondary products and the wastes such as culm chaffs as the tertiary products. [0129] The wirmowing fan 120, as receiving the power from the engine 20 transmitted via the belt transmission mechanism 25, is driven to rotate about the winnowing fan drive shaft 26, thereby to generate sorting air flow. This sorting air flow travels through three air passageways R1-R3 to be fed to the sorting processing material dropped from the receiving mesh 117 or the sorting processing material to be sorted by the swinging sorting mechanism 119, so that the chaffs or the like having the smaller specific weight will be blown off the sorting processing material and conveyed toward the discharge opening 123 provided on the downstream in the threshing process direction.

[0130] The primary collecting section 121 collects, as the primary products, the separated grains dropped from the grain sieve 134 of the swinging sorting mechanism 119, with the dusts such as straw dusts having been removed by the sorting air flow from the winnowing fan 120. At the bottom of this primary collecting section 121, there is arranged a primary screw conveyer 28 under the right/left orientation which is driven by the power from the engine 20 transmitted via the winnowing fan 120 etc. The primary screw conveyer 28 conveys the primary products collected at the primary collecting section 121 toward an elevating feeder screw 137 (see Fig. 2) provided continuously from its right end.
[0131] The secondary collecting section 122 collects, as the secondary products, the mixture with the grains with branches attached thereto, culm chaffs which were not dropped from the grain sieve 134 of the swinging sorting mechanism 119 but flown down from the rear end of the grain sieve 134 and the mixture witTTffi^e^Fains^wifh^ branches attached thereto, culm chaffs which were dropped from the straw rack 132 of the swinging sorting mechanism 119. At the bottom of this secondary collecting section 122, there is arranged a secondary screw conveyer 29 under the right/left orientation which is driven by the power from the engine 20 transmitted via the winnowing fan 120 etc. The secondary screw conveyer 29 conveys the secondary products collected at the secondary collecting section 122 toward a secondary returning mechanism 139 (see Fig. 2) provided continuously from its right end. [0132] The elevating feeder screw 137 feeds upward the primary products which have been conveyed by the primary screw conveyer 29 and feeds them into the bag charging tank 6a mounted upwardly of the grain bag charging section 6 (see Fig. 1 and Fig. 2). The secondary returning mechanism 139 includes a re-processing section (not shown) for effecting again a threshing operation on the secondary products which have been conveyed by the secondary screw conveyer 29 and then feeds upwards the re-processed secondary products after the re-processing at this re-processing section back to the swinging sorting mechanism 119 (see Fig. 2 and Fig. 11).
[0133] The discharging opening 123 discharges, to the outside of the vehicle body, the threshed culms which were not dropped from the receiving mesh 117 but flowed down from the culm discharging opening 118, or the culm chaffs which have been sorted and conveyed to the rear of the swinging sorting mechanism 119 by the sieve sorting operation or the blow sorting operation.
[0134] As shown in Figs. 11-17, the threshing drum 5a includes a conically shaped raking-in section 141 forming the front end of the drum and a threshing processing

section 142 provided continuously from the rear end of the raking-in section 141. On the outer peripheral face of the raking-in section 141. there are mounted a plurality of spiral blades (an example of spiral teeth) 143 for raking in the harvested culms which have been conveyed and fed to the feeding opening 125 by the feeder 11 toward the threshing processing section 142 disposed rearward in association with rotation of the threshing drum 5a.
[0135] The threshing processing section 142 includes a first plate (an example of support member) 144 provided integrally to the front portion of the threshing drum output shaft 38, a second plate (an example of partitioning member) 145 provided integrally to the fore/aft intermediate portion of the threshing drum output shaft 38, a third plate (an example of support member) 146 provided integrally with the rear end of the threshing drum output shaft 38, six threshing drum frames (example of bar-like members) 147 comprised of e.g. round steel pipeFsuppdrted'Md~spaced~apaiTWithT fixed distance along the peripheral direction of the threshing drum 5a under the fore/aft oriented posture along the threshing drum output shaft 38 by these plates 144-146, and a plurality of threshing teeth 148 mounted on the respective threshing drum frames 147 in juxtaposition and spaced apart from each other with a predetermined distance therebetween in the fore/aft direction under posture projecting to the outside of the drum, etc.
[0136] That is to say, the threshing drum 5a mounts the plurality of threshing teeth 148 arranged in juxtaposition and spaced apart with the predetermined distances therebetween in the peripheral direction of the threshing processing section 142 and the fore/aft direction. Further, the threshing drum 5a is configured such that an iimer space S of the threshing processing section 142 is communicated with the threshing chamber 114 so as to allow introduction of the processing material into this inner space S. As a result, during the rotational operation of the threshing drum 5a, the processing material present in the periphery and the processing material introduced into the inner space S are stirred and at the same time the threshing operation by the impacting and raking-in actions of the threshing drum frames 147 and the threshing teeth 148 is effected on these processing materials.
[0137] Moreover, as the inner space S of the threshing processing section 142 is communicated with the threshing chamber 114, even if a large amount of harvested culms are fed as the threshing material into the threshing chamber 114, the inner space S of the threshing processing section 142 can be effectively utilized as the processing space. "With this, it is possible to avoid dwelling or stagnation of the processing material in the processing space or saturation of the processing space.

As a result, it is possible to avoid such inconvenience that the processing material drops from the receiving mesh 117 without being sufficiently threshed, due to the dwelling of the processing material in the processing space or the saturation of the processing space or the increase in the load required for the threshing process results in damage to the transmission linen for the threshing drum 5a. [0138] And, during the rotational operation of the threshing drum 5a, not only the threshing teeth 148, but also the threshing drum frames 147 forming the threshing processing section 142 of the threshing drum 5a act as the threshing members to act on the processing material. As a result, it is possible to improve the threshing performance and threshing efficiencv.
[0139] Also, at the fore/aft intermediate portion of the threshing drum 5 a where the processing material amount is decreased as many grains have already been separated
by the threshing operation at the fronrsTde^fth^threshing~drum3¥^Ii3"dropped^fom* the receiving mesh 117, the second plate 145 partitioning the iimer space S of the threshing drum 5a between the front section and the rear section acts to prevent flow of the processing material in the inner space S of the threshing drum 5a toward the downstream side in the threshing process direction, but instead guides this material to the periphery of the threshing drum 5a in association with rotation of this threshing drum 5a, so as to promote threshing actions on the processing material by the impacting and raking-in actions of the plurality of threshing teeth 148 or the like and promoting dropping of the separated grains from the receiving mesh 117 also. As a result, it becomes possible to avoid the generation of tertiary loss which would occur if the separated grains or un-threshed culms contained in the processing material pass through the inner space S of the threshing drum 5a without being threshed and discharged from the culm discharging opening 118 formed at the downstream end in the threshing process direction, together with the threshed grains. [0140] Moreover, during the rotational operation of the threshing drum 5a, together with the harvested culms raked in and conveyed by the action of the raking-in section 141, ambient air introduced through the feeding opening 125 in association with the rotation of the spiral blades 143, will flow smoothly to the periphery of the threshing drum 5 a or into the inner space S of the threshing processing section 142. With this, it is possible to prevent unwanted flowing of the culm chaffs or the like generated in the threshing operation from the feeding opening 125 to the feeder 11 and also to allow speedy conveyance of the processing material to the downstream side in the threshing process direction, also. [0141] In addition to the above, the ambient air introduced from the feeding

opening 125 passes the inside of the feeder 11 connected to the feeding opening 125 and this feeder 11 communicates the discharge opening (not shown) for conveying the collected culms formed in the harvesting collection section of the harvesting conveying device 4 mounting-the harvesting device 16, the auger 18, etc. with the feeding opening 125. Therefore, during the rotational operation of the threshing drum 5a, the sucking action associated with the rotation of the spiral blades 143 also helps the flowing movement of the culm chaffs, dust etc. generated in the harvesting process or the collecting process at the harvesting collection section in cooperation with the ambient air, from the discharging opening of the harvesting collecting section to the inner space of the feeder 11 and from the feeding opening 125 to the periphery of the threshing drum 5a or the inner space S of the threshing processing section 142. As a result, it becomes possible to restrict occurrence of adhesive
accumulation or stirring-up of chaffs^'orlheTili^TtlliFlTafveMing^collec^^
and consequently to restrict deterioration in the working environment or in the
visibility, due to conveying trouble of the harvested culms due to such adhesive
accumulation.
[0142] Each plate 144-146 is formed circular about the harvesting output shaft 38
and at positions in the outer peripheral side of the plate and equidistant from the
threshing drum output shaft 38, threshing drum frames 147 are bolt-connected. That
is to say, on the outer peripheral side of the respective plates 144-146, the six
threshing drum frames 147 are arranged in juxtaposition with a predetermined
distance therebetween in the peripheral direction thereof, so as to enlarge the drum
diameter of the threshing drum 5a. With this, it is possible to prevent intertwining of
the harvested culms relative to the threshing drum 5a.
[0143] Each threshing drum frame 147 is bolt-connected to the respective plate
144-146 in such a manner that the frame is switchable in its posture between a normal
posture wherein the fore/aft direction of the frame is in alignment with the fore/aft
direction of the threshing drum 5a and a reverse posture wherein its fore/aft direction
is in reverse to the fore/aft direction of the threshing drum 5a, and also that the
fore/aft directions of the adjacent threshing drum frames 147 are opposite to each
other.
[0144] In each threshing drum frame 147, a plurality of attaching holes 147A, 147B
for allowing attachment of the threshing teeth 148 are formed in juxtaposition with a
predetermined pitch P in its fore/aft direction and a distance LI from the front end of
the threshing drum frame 147 to the center of the first front attaching hole 147A is
made different by half a pitch (=1/2 P) from a distance L2 from the rear end of the

threshing drum frame 147 to the center of the last attaching hole 147A. [0145] And. the respective threshing drum frames 147 are connected and supported to the respective plates 144-146 in such a manner that the adjacent frames 147 have opposite orientations in the fore/aft direction from each other. With this, while identical frames are employed as the six threshing drum frames 147, it is possible to arrange the threshing teeth 148 to be mounted on each threshing drum 147 with half-pitch displacement in the fore/aft direction relative to the threshing teeth 148 of the adjacent threshing drum 148. As a result, it is possible to reduce the impacting distance of the threshing teeth 148 relative to the processing material, without reducing the spacing between adjacent threshing teeth 148.
[0146] That is to say, with the above construction, the cost reduction is made possible through the use of identical threshing drums 147, and at the same time, jamming of processing material due to intertwiming oflS^^culmslnTRe processing'" material relative to the threshing teeth 148 is effectively avoided and with increased in the number of impacts by the threshing teeth 148 to the processing material, the threshing efficiency can be improved.
[0147] Also, as each threshing drum 147 is mounted to be switchable between the normal posture and the reverse posture, when significant wear due to use for an extended period of time has occurred in the threshing teeth 148 located on the upstream side in the threshing process direction which tend to be worn relatively easily because of the larger amount of processing material, by switching over the orientation of the respective threshing drum frames 147, the plurality of threshing teeth 148 mounted on each threshing drum frame 147 can be changed in position at one time between the threshing teeth 148 located on the upstream side in the threshing process direction relatively likely to be worn out and the threshing teeth 148 located on the downstream side in the threshing process direction less likely to be worn out. As a result, the threshing teeth 148 located on the downstream side in the threshing process direction with less wear can be effectively used as the threshing teeth 148 on the upstream side in the threshing process direction more likely to be worn out.
[0148] Of the plurality of attaching holes 147A, 147B, four (two on each of the front and rear sides) attaching holes 147A located on the front and rear extreme ends of each threshing drum frame 147 have a smaller diameter than the attaching holes 147B located at intermediate positions.
[0149] Of the respective threshing teeth 148, the threshing teeth 148A to be attached using the smaller diameter attaching holes 147A are formed of round steel

bar members with stepped portions having smaller-diameter portions 148a to be inserted into the attaching holes 147A and are detachably nut-attached to the threshing drum frame 147 in such a manner that the centers thereof are located on a line passing the center of the threshing-'drum output shaft 38 and the center of the threshing drum frame 147.
[0150] Whereas, the threshing teeth 148B to be attached using the intermediate attaching holes 147B are formed of stepless round steel bar members and are non-detachably attached to the threshing drum 148 in such a manner that the centers thereof are located on the line passing the center of the threshing drum output shaft 38 and the center of the threshing drum frame 147.
[0151] That is to say, as the respective threshing teeth 148A located at the front and rear extreme ends of the threshing processing section 142 are detachable, then, if
significant wear due to use for an extMTded'^enod"^lime^as~occufredTir"thes'e' threshing teeth 148 A, even wnth the orientation change of the threshing drum frames 147, these teeth 148A can be easily replaced by new ones.
[0152] Further, on the downstream side in the threshing process direction where the amount of threshed culms is greater, as shown in Fig. 18, the threshing teeth 148A located at the rear end of the threshing drum 5a may be provided with "thinning-out". With this, the distance between the threshing teeth 148A at the rear end of the threshing drum is made greater, so that it becomes possible to effectively restrict occurrence of dwelling of threshed culms due to intertwining thereof relative to the threshing teeth 148 A at the rear end of the threshing drum. As a result, it becomes possible to promote the discharge of the threshed culms from the culm discharging opening 118.
[0153] As shown in Figs. 11-13, Fig. 19(a), (b) and Fig. 20, the top plate 124 integrally includes a curved portion 124A curved substantially along the rotational path of the leading ends of the threshing teeth, semi-circular vertical wall portions 124B disposed at the front and rear opposed ends of the curved portion 124A and straight side edge portions 124C disposed on the right and left sides of the curved portion 124A. The top plate 124 is constructed to be pivo tally opened and closed via a plurality of hinges 124D attached to the left side edge portion 124C, between a closed position where the plate 134 covers the upper side of the threshing drum 5a and an opened position where the upper side of the threshing drum 5 a is opened up. The right side edge portion 124C includes a plurality of bolts 124E for fixing the top plate 124 under the closed condition. [0154] The curved portion 124A is curved in such a manner as to smoothly guide,

with its inner face, the processing material conveyed to the upper portion of the threshing drum 5a in association with rotation of the threshing drum 5a toward the receiving mesh 117 disposed downwardly. On the inner face of the curved portion 124 A, there are detachably attached a plurality of dust sending valves 149 juxtaposed with a predetermined distance therebetween in the fore/aft direction, the dust sending valves 149 being operable to guide the processing material which has been conveyed to the upper section of the threshing chamber 114 in association with rotation of the threshing drum 5a, toward the downstream side in the threshing process direction. Of these dust sending valves 149, the first front dust sending valve 149A is formed arcuate from the front side vertical wall portion 124B to the left side lateral edge portion 124C, and the other dust sending valves 149B are formed arcuate between the right and left side edge portions 124C.
[0155] That is to say,^wth^rovi?ro"n^o^f tli^^rved'poiti^
the processing material which has been conveyed upward to the upper section of the threshing chamber 114 by the plurality of threshing teeth 148 or the like in association with rotation of the threshing drum 5a, can be smoothly guided along the inner face of the curved portion 124A and the dust sending valves 149, toward the receiving mesh 117 disposed on the downstream in the threshing process direction. Further, as each dust sending valve 149 is formed elongate and arcuate from the left side edge portion 124C or between the right and left side edge portions 124C, the guiding action by the respective dust sending valve 149a on the processing material which has been conveyed to the upper section of the threshing chamber 114 can be improved. With this, while each threshing tooth 148 is not provided with any form having a conveying action for the processing material, but with the form dedicated for threshing, suitable for impacting or raking-in the processing material, yet, the processing material can be effectively conveyed and guided toward the downstream side in the threshing process direction. As a result, the threshing performance and the conveying performance for the processing material can be improved. [0156] To each one of the right and left side edge portions 124C, there is detachably bolt-connected a join member 150 made of steel plate and curved so as to have a guide face 150a for continuously interconnecting the inner face of the curved portion 124A and the inner face of the receiving mesh 117. With this detachable attachment of the join member 150 subjected to strong and violent contact with the processing material because of its positioning at the join between the receiving mesh 117 and the top plate 124, if this join member 150 becomes significantly worn out due to the contact with the processing material, this join member 150 alone can be

replaced easily. That is to say. if this join member 150 were non-detachably welded to the top plate 124 for instance, this would require replacement of this join member 150 together w'ith the entire top plate 124, which would be uneconomical and troublesome. The above arrangement allows an-appropriate measure to be taken for such wear of the join member 150, without inviting such disadvantages. [0157] Incidentally, between the leading end of each threshing tooth 148 and the lower edge of each dust sending valve 149, there is set a small clearance for improving the guiding of the processing material by the dust sending valve 149. Also, between the leading end of each threshing tooth 148 and the inner face of the receiving m-csh 117^ in order to promote the dropping of separated grains from the receiving mesh 117, there is set a clearance greater than the clearance set between the leading end of each threshing tooth 148 and the lower edge of each dust sending valve
149^ '^ ^"^
[0158] As shown in Fig. 11, Fig. 12, Figs. 14-16 and Fig. 18, in the threshing drum 5a, on the outer peripheral face of its raking-in section 141, two support plates 141A are welded in a spiral form, and to the rear faces of these respective support plates 141 A, corresponding spiral blades 143 are detachably bolt-cormected, with the outer edges of the blades projecting more outwards than the outer edges of the support plate 141A corresponding thereto.
[0159] That is to say, with this threshing drum 5a, the harvested culms which have been supplied and conveyed to the feeding opening 125 by the feeder 11, in association with the rotation of the drum, are raked in and conveyed to the rearward. In the course of this, there occurs violent contact with the processing material in the two spiral blades 143 and resultant frictional wear tends to occur in the same. Then, with the above construction, these two spiral blades 143 are detachably mounted to the raking-in section 141 of the threshing drum 5a. With this, if significant frictional wear has occurred in the respective spiral blade 143 through its use for an extended period of time, this spiral blade 143 alone can be replaced easily. If this spiral blade 143 were non-detachably welded to the raking-in section 141 for instance, this would require replacement of this worn spiral blade 143 together with the raking-in section 141, which would be uneconomical and troublesome. The above arrangement allows an appropriate measure to be taken for such wear of the spiral blade 143, without inviting such disadvantages.
[0160] Incidentally, each support plate 141A is reinforced by a plurality of reinforcing ribs 141B welded to and between the front face of the plate and the outer peripheral face of the raking-in section 141.

[0161] As shown in Fig. 11, Fig. 12, Fig. 14, Fig. 21 and Fig. 22, in the threshing apparatus 5, between its front wall 126 and the receiving mesh 117, there is disposed a conveyance assisting guide 151 for receiving the harvested culms fed and conveyed to the feeding opening 125 by the feeder 11 and assisting the raking-in conveyance of the harvested culms by the two spiral blades 143. This conveyance assisting guide 151 comprises a pair of left and right guide members 151 A, 15IB bolt-cormected in substantially U-shape in front view to cover the lower side of the raking-in section 141 from under. The left and right guide members 151 A, 15IB are constructed such that a second plate 151b made of stainless steel forming the guide face extending from the front wall 126 of the threshing apparatus 5 to the receiving mesh 117 is welded to a first plate 151a made of stainless steel detachably bolt-cormected to a pair of right and left support frames 152 disposed under the fore/aft orientation at an
upper section of the threshing apparatus 5.
[0162] That is to say, with this threshing apparatus 5, the conveyance assisting guide 151 which assists the raking-in conveyance of the harvested culms by the two spiral blades 143, thus being subjected to violent contact with the harvested culms, hence being easily worn out, is detachably mounted. Also, the construction is provided as a right/left two-part dividable construction, between the left guide member 151A disposed on the upstream side in the rotational direction of the threshing drum 5a and the right guide member 15IB disposed on the downstream side in the rotational direction of the threshing drum 5a. With these, if the entire conveyance assisting guide 151 has been significantly worn out due to its use for an extended period of time, this conveyance assisting guide 151 alone can be easily replaced. Further, if one of the left and right guide members 151 A, 151B of the conveyance assisting guide 151 has been significantly worn out due to use for an extended period of time, the significantly worn guide member 151A or 15IB alone can be easily replaced. That is, if the conveyance assisting guide 151 were non-detachably welded to the receiving mesh 117 or the right and left support frame 152, or if the conveyance assisting guide 151 were provided as a non-dividable construction, significant wear of only one of the right and left sides of the conveyance assisting guide 151 would require replacement of the entire conveyance assisting guide 161, which would be uneconomical and troublesome. The above arrangement allows an appropriate measure to be taken for such wear of the conveyance assisting guide 151, without inviting such disadvantages. [0163] Moreover, as the conveyance assisting guide 151 is formed of stainless steel which has high corrosion resistance and high strength, the frequency of replacement

due to its wear can be reduced.
[0164] As shown in Fig, 11, Fig. 13, Fig. 14 and Fig. 23, the receiving mesh 117 consists of four receiving mesh members 153 of an identical shape and is detachably bolt-connected to the right and left support frames, 152. Each receiving mesh member 153 includes a base frame 153A which is rectangular. Within the framework of the base frame 153A, there are arranged a plurality of vertical crosspieces 153B formed of strip-like steel plates with the fore/aft orientation and with a predetermined distance therebetween in the peripheral direction of the threshing drum 5a. Also, there are arranged a plurality of first lateral crosspieces 153C formed of strip-like steel plates with the right/left orientation and with a predetermined distance therebetween in the fore/aft direction which is the axial direction of the threshing drum 5a. Moreover, there are arranged a plurality of
second lateral crosspieces^TS3r)"lofmed of afcMT^^'bMt'iyrarro^wiresr^witlr-the^ right/left orientation and with a predetermined distance therebetween in the fore/aft direction, between the adjacent first lateral crosspieces 153C. And, the disposing spacings of the respective crosspieces 153B-153D are set such that the meshes formed within the framework of the base frame 153A have a laterally elongate rectangular shape, with the length thereof along the peripheral direction of the threshing drum 5a being longer than the length thereof along the fore/aft direction. [0165] That is to say, at the time of threshing operation when the threshing drum 5a is rotatably driven, separated grains obtained by the threshing operation on the harvested culms or the like will flow in this rotational direction in association with the rotation of the threshing drum 5a. Then, taking this into consideration, the receiving mesh 117 is configured such that its meshes have the laterally elongate rectangular shape elongate in the rotational direction of the threshing drum 5a. With this, in comparison with the case of the meshes of the receiving mesh 117 as vertically elongate rectangular shape which is elongate in the threshing operation direction (the fore/aft direction) of the threshing drum 5a, the above arrangement facilitates the dropping of the separated grains or the like from the front end side of the receiving mesh 117. As a result, it becomes possible to effectively restrict occurrence of dropping of threshed grains, due to restricted dropping of separated grains from the front side of the receiving mesh 117. Further, as the respective receiving mesh members 153 are formed in the identical shape to each other, the productivity and the assembly readiness of the receiving mesh 117 can be improved. [0166] As shown in Fig. 11 and Fig. 24, the rough sorting chaff sieve 131 comprises a single sorting plate 154 which is bolt-connected to a sieve case 129,

under a rearwardly inclined posture which rises toward the downstream side its sorting direction.
[0167] At the front side portion of the sorting plate 154 (about 1/3 front area relative to the entire sorting plate 154), there are formed a plurality of dropping holes 154A each having a rectangular shape in its plan view, with the holes 154A being arranged in the staggered pattern, with the rear row of the dropping holes 154A being located respectively between the front row of dropping holes 154A. At the rear side portion of the sorting plate 154 (about 2/3 rear area relative to the entire sorting plate 154), there are formed a plurality of dropping holes 154B, 154C each having a rectangular shape in its plan view having a sorting piece 154a. 154b. with the holes 154B, 154C being arranged in the staggered pattern, with the rear row of the dropping holes 154B, 154C being located respectively between the front row of dropping holes 154B,
154C. ~" "~
[0168] Of the respective sorting pieces 154a, 154b, the sorting piece 154a located at the right/left center of the sorting plate 154, is formed by punching out in the form of a scale which is formed narrower and upper toward the downstream side in its sorting direction. The sorting pieces 154b located on the right and left opposed sides of the sorting plate 154 have a rectangular shape shorter than the sorting piece 154a located at the right/left center and is formed by punching out, which extends upward toward the downstream side in its sorting direction.
[0169] That is to say, as the rough sorting chaff sieve 131 is comprised of a single sorting plate 154, in comparison with the case of e.g. forming the chaff sieve 131 of many chaff rips made of strip steel plates arranged with a predetermined distance therebetween in the fore/aft direction, it is possible to simplify the construction and to reduce the costs.
[0170] And, with the formation of the dropping holes 154A not having sorting piece 154a, 154b at the front side portion of the chaff sieve 131 to which processing material with high content of separated grains is fed, more separated grains will drop from the front portion of the chaff sieve 131 onto the grain pan 133 or the grain sieve 134 disposed downwardly. As a result, it becomes possible to increase the collection ratio of separated grains at the primary collecting portion 121 disposed under the grain pan 133 and the grain sieve 134.
[0171] Also, as the dropping holes 154B, 154C having the sorting pieces 154a, 154b are arranged in the staggered pattern in the fore/aft direction and the right/left direction at the front portion of the chaff sieve 131, in the sieving sorting process, the sorting material on the chaff sieve 131 will be distributed uniformly without any

concentration in the right/left direction, whereby the dropping of the separated grains
from the respective dropping holes 154B, 154C can be promoted.
[0172] Moreover, as the chaff sieve 131 is mounted under the rearwardly elevated
posture, in comparison with mounting the chaff sieve 131 under the horizontal
posture, in the sieving sorting process, the chaff sieve 131 can exert a greater
pressing force upward to the upstream side in the sorting process direction.
Therefore, during the sieving sorting process, conveyance of the sorting material
toward the downstream side in the sorting direction can be restricted and also there
occurs a greater vertical movement in the sorting material, so that the
gravity-difference sorting of the sorting material can be effected more effectively.
Accordingly, dropping of the grains of greater specific weights through the dropping
holes 154B, 154C is promoted and also generation of tertiary loss of separated grains
being~disch"arge"dWrou^The^discha^^^^ —
be effectively restricted. As a result, the grain collecting efficiency can be improved.
[0173] In addition, the sorting pieces 154b on the right and left ends of the chaff sieve 131 are formed shorter than the sorting pieces 154a at the right/left center, dropping of the grains or the like from the dropping holes 154C where the sorting material in the chaff sieve 131 tends to accumulate, can be promoted. Consequently, it is possible to avoid deterioration in the sorting efficiency due to such accumulation of sorting material at the right and left ends of the chaff sieve 131. [0174] Incidentally, the ratio between the dropping holes 154A not having the sorting pieces 154a, 154b and the dropping holes 154B, 154C having the sorting pieces 154a, 154b to be formed in the chaff sieve 131 can vary, depending on e.g. the type of grains to be sorted.
[0175] Further, in the front portion of the sorting plate 154, the plurality of dropping holes 154C having the rectangular shape and provided with the shorter and rectangular sorting pieces 154b can be formed in the staggered pattern, with the rear row dropping holes 154C being located between the front row dropping holes 154C. [0176] As shown in Fig. 11, arrangement is provided such that of the sorting air flow form the winnowing fan 120, the air flow portion passing the upper-stage air passageway Rl will pass the air passageway R4 provided in the sieve case 129 and flow toward the second plate 145 of the threshing drum 5a. With this arrangement, the processing material which is prevented, by the second plate 145, from flowing to the downstream side in the threshing process direction can be air-conveyed toward the periphery of the threshing drum 5a. As a result, it is possible to avoid the risk of

the processing material becoming accumulated immediately before the second plate 145 to interfere with the threshing operation.
[0177] As shown in Fig. 11 and Fig. 14, the threshing drum 5a is constructed such that the threshing teeth 148A at its rear end are disposed more rearward than the rear end of the receiving mesh 117 to face the culm discharging opening 118. That is to say, at the rear end of the threshing drum 5a, the receiving mesh 117 is not present, thus creating a relatively large space in its periphery. With this arrangement, even when the threshed culms become entangled with the threshing teeth 148A provided at the rear end of the threshing drum, these threshed culms will be urged to detach from the leading ends of these threshing teeth 148A, as being aided by the effect of centrifugal force associated with rotation of the threshing drum 5a. As a result, it becomes possible to restrict occurrence of dwelling of threshed grains due to their
intertwining with the threshing teeth 148A at the rear eM oTtEe tEfe~sTiing^drumrTa, and to promote the discharge of the threshed culms from the culm discharge opening 118.
[0178] As described above, according to the present invention, in the threshing apparatus 5 having the threshing drum 5a which is rotatably driven about the support shaft (threshing drum output shaft 38) thereby to effect a threshing operation on the harvested culms charged into the threshing chamber 114, the threshing drum 5a comprises the plurality of bar-like members (threshing drum frames 147) having a circular cross section and arranged along the support shaft and in juxtaposition with a predetermined space therebetween in the peripheral direction of the threshing drum 5a, the support members (first plates 144, the third plates 146) provided before and after the support shaft to support the bar-like members, and a plurality of threshing teeth 148 provided in each bar-like member and having a circular cross section and juxtaposed with a predetermined distance therebetween in the fore/aft direction under the posture projecting cantilever-wise from each bar-like member to the outside of the threshing drum 5a.
[0179] According to this construction, the threshing drum 5a is provided, therein, with a space communicated with the threshing chamber 114 and allows introduction of the threshing material into this inner space. Therefore, during its rotational operation, while the threshing material present in its periphery and the threshing material introduced into the inner space are being stirred, these threshing materials are subjected to the threshing operation by the impacting and raking-in actions by the plurality of bar-like members (threshing drum frames 147) and the threshing teeth 148.

[0180] That is to say, even when a great amount of harvested culm, as threshing material, is fed into the threshing chamber 114, the inner space of the threshing drum 5a can be effectively utilized as the treating space for the threshing operation. As a resillt, dwelling or stagnation of threshing material in the treating,,^space and saturation of the treating space can be avoided. As a result, it is possible to prevent such inconvenience that the material, without being processed sufficiently, would leak down through the receiving mesh or that the load required for the threshing operation would increase to invite damage to the transmission line for the threshing drum 5 a.
[0181] Moreover, as the plurality of bar-like members (threshing drum frames 147) are arranged in juxtaposition and with a predetermined spacing therebetween along the fore/aft direction, it is possible to prevent intertwining of long culms with the bar-like members, thus avoiding dwelling of" thfeshihg~lnaterial~3ue to such" intertwining. Further, at the time of the rotational operation of the threshing drum 5a, not only the plurality of threshing teeth 148, but also the plurality of bar-like members forming the drum body portion of the threshing drum 5 a function as the threshing treating members for effecting the threshing operation by impacting and to raking on the threshing material. Consequently, the threshing ability can be improved.
[0182] Also, as the bar-like members (threshing drum frames 147) and the threshing teeth 148 have circular-shaped cross sections and no sharp edged portions are present in the bar-like members or the threshing teeth 148, the impacting by the bar-like members and the threshing teeth 148 hardly provides damage to the threshing material.
[0183] Further, the threshing teeth 148 project cantilever-wise from the bar-like members (threshing drum frames 147) to the outside, and the leading ends of the threshing teeth 148 are free (the condition of not being connected to any member or component), the threshing material if intertwined with the threshing teeth 148 can move easily to the outer side along the threshing teeth 148 by the effect of centrifugal force associated with rotation of the threshing drum 5a and can readily detach from the leading ends of the threshing teeth 148. Hence, intertwining of the threshing material with the threshing teeth 148 and being locked thereto will hardly occur. [0184] Further, the arrangement of making the bar-like members (threshing drum frames 147) switchable in their orientation between the normal posture and the reverse posture reverse in the fore/aft direction provides the following advantages. [0185] With the threshing apparatus 5 in general, frictional wear occurs more

conspicuously in the threshing teeth 148 located in the front portion of the threshing drum 5a and frictional wear occurs less likely in the threshing teeth 148 located in the rear portion of the threshing drum 5a. This is because harvested culms are fed through the feeding opening 125 into the-threshing chamber 114 and the threshing operation of the harvested culms is effected mainly in the front portion of the threshing drum 5a and threshed material drops from the receiving mesh 117 and toward the rear side of the threshing chamber 114, the amount of non-threshed harvested culms is smaller.
[0186] Therefore, according to the present construction, at first, the bar-like members (tb^reshing drum frames 1^7) will be set under the normal posture, and as frictional wear develops in the threshing teeth 148 located in the front portions of the bar-like members, these bar-like members may be switched over in their posture.
Accordingly, in the bar-like member having deveropedTlfncfional^^wear liTtts" threshing teeth 148, these threshing teeth 148 having developed frictional wear can be located in the front portion of the bar-like member. As a result, the useful life of the bar-like member as a whole can be extended advantageously. [0187] For instance, if the threshing teeth 148 were attached between and across adjacent bar-like members, when the orientation of the bar-like member is to be changed, if the threshing teeth 148 are attached to a bar-like member whose orientation needs to be changed and a further bar-like member whose orientation does not need to be changed, the desired change in the orientation of the bar-like member needing the orientation change could not be done unless the threshing teeth 148 are removed therefrom. Further, if the threshing teeth 148 were attached across and between a plurality of bar-like members adjacent each other, it would be needed to change the orientations of all of these plural bar-like members and the orientation change would not be possible with the single bar-like member alone. [0188] On the other hand, according to the inventive construction described above, the threshing teeth 148 project cantilever-wise from the bar-like member to the outside and the leading ends of the threshing teeth 148 are kept free (not being connected to any member or component). Therefore, when change of orientation of a bar-like member is to be done, there is no need to remove the threshing teeth 148 and the orientation change is possible by the single bar-like member alone. And, the other bar-like member(s) not needing orientation change can be left under the normal posture.
[0189] Further, the arrangement of rendering the threshing teeth 148 located in the front portion of the bar-like member detachable and rending the threshing teeth 148

located at the intermediate portion of the bar-like member non-detachable^ provides the following advantage.
[0190] As described above, with the threshing apparatus 5 in general, the frictional wear occurs^ more conspicuously in the threshing teeth 148 located in the front portion of the threshing drum 5a. In this respect, according to the inventive construction, when frictional wear has developed in the threshing teeth 148 located in the front portion of the bar-like member (threshing drum frame 147), by replacing these threshing teeth 148 in the front portion of this bar-like member, the usable life of the bar-like member as a whole can be extended advantageously. [0191] In this case, v,'hen the threshing teeth 148 were made detachable, this would result in additional complication of the construction. Therefore, by making non-detachable the threshing teeth 148 located at the intermediate portion where the
progress of frictional wear is slower than at the front portionlSTthelDaf^ke'mem^er," rather than making all of the threshing teeth 148 of the bar-like member detachable, it is possible to restrict such additional complication of the construction of the bar-like member.
[0192] Also, at the front end section of the threshing drum 5a, there are provided the spiral teeth (spiral blades 143) for raking-in and conveying the harvested culms to the rear side.
[0193] If the threshing teeth 148 have circular cross sections as described above, this makes it difficult for the threshing teeth 148 to provide the function of conveying the harvested culms or threshing material rearward.
[0194] On the other hand, in the case of providing the threshing teeth 148 with the circular cross sections, according to the inventive construction, as the spiral teeth (spiral blades 143) are provided at the front end portion of the threshing drum 5 a, the harvested culms which have been fed through the feeding opening 125 into the threshing chamber 114 will be conveyed rearward without dwelling by the spiral teeth; hence, it is possible to prevent jamming due to dwelling of the harvested culms which have been fed through the feeding opening 125 into the threshing chamber 114.
[0195] Further, there is provided the partitioning member (the second plate 145) which partitions the inner space of the threshing drum 5a between the front section and the rear section. Therefore, this partitioning member serves to prevent flow toward the downstream side in the threshing process direction, of e.g. non-threshed culms which may have entered the inner space of the threshing drum 5a at the earlier stage of the threshing process, so that such separated grains or un-threshed culms will

be guided to the periphery of the threshing drum 5a in association with rotation of the threshing drum 5a. Accordingly, it is possible to prevent generation of tertiary loss due to discharge of the threshed grains and/or un-threshed culms from the downstream end in the threshing process direction,- as such threshed grains and the un-threshed culms just pass the inner space of the threshing drum without being treated.
[0196] Therefore, even when a large amount of threshing material is fed, a sufficient threshing operation may be provided on this threshing material, without inviting increase in the load required for the threshing operation and generation of tertiary loss can be prevented. Hence, it is possible to improve the threshing ability and the grain collecting efficiency with avoiding damage to the threshing drum transmission line due to increase in the load. Consequently, it becomes possible to
provide a construction of a threshing drum 5a for a thres5ihg^apparatus"5~~whTc3r
construction is superior in the durability and the processing ability.
[0197] Further, the winnowing fan 120 for generating sorting air flow is provided
and the arrangement is made such that the sorting air flow from the winnowing fan is
caused to flow toward the partitioning member (second plate 145).
[0198] With this construction, threshing material stopped by the partitioning
member (the second plate 145) will be sorted by the sorting air flow from the
winnowing fan 120 toward the periphery of the partitioning member (periphery of the
threshing drum 5a) and will flow from the periphery of the partitioning member
toward the downstream side in the threshing process direction. As a result, it
becomes possible to avoid the risk of accumulation of the threshing material
immediately before the partitioning member.
[0199] Accordingly, it is possible to prevent deterioration in the processing
performance due to accumulation of threshing material.
[0200] Further, the arrangement of detachably connecting the bar-like members
(threshing drum frames 147) to the partitioning plate (second plate 145) provides the
following advantages.
[0201] As described above, in case there is provided the partitioning member for
partitioning the inner space of the threshing drum 5a between the front section and
the rear section, the bar-like members have their front and rear portions supported to
the support member and have their intermediate portions supported to the
partitioning member, so that the bar-like members are supported with sufficient
strength.
[0202] Therefore, if the bar-like member is adapted to be switchable in its posture

between the normal posture and the reverse posture reverse in the fore/aft direction, with the inventive construction above, as the bar-like member is detachably attached to the partitioning member, the switchover the orientation of the bar-like member between the normal'posture and the reverse posture can be effected smoothly. [0203] Further, the arrangements of providing the top plate 124 for covering the upper side of the threshing drum 5a and providing this top plate 124 with the dust sending valves 149 for guiding the threshing material conveyed to the upper section of the threshing chamber 114 in association with rotation of the threshing drum 5a, toward the rear side provide the following advantages.
[0204] If the threshing teeth 148 have circular cross sections as described above, this makes it difficult for the threshing teeth 148 to provide the function of conveying the harvested culms or threshing material rearward.
[0205] On the other hand, in the case of providinglEeTSfe^sEing teetiri4'8"^tlrfh'e^ circular cross sections, according to the inventive construction, as the top plate 124 for covering the upper side of the threshing drum 5 a with the dust sending valves 149, the threshing material will not dwell in the threshing chamber 114, but will be guided to the rear side by the dust sending valves 149, so it is possible to prevent jamming due to dwelling of threshing material in the threshing chamber 114. [0206] Further, the arrangement of providing the dust sending valve 149 with a length extending between the right and left lateral edges of the top plate 124 provides the following advantage.
[0207] As described above, in the case of providing the top plate 124 for covering the upper side of the threshing drum 5a with the dust sending valves 149, according to the inventive construction above, the dust sending valve 149 is provided with a length extending between the right and left lateral edges of the top plate 124. By providing the dust sending valve 149 with such sufficient length, the threshing material will not dwell in the threshing chamber 114, but will be guided to the rear side by the dust sending valves 149.
[0208] Further, the arrangement of forming the top plate 124 with such as curve as to substantially follow the rotational path K of the leading ends of the threshing teeth 148 in association with rotation of the threshing drum 5a provides the following advantage.
[0209] As described above, in the case of providing the top plate 124 for covering the upper side of the threshing drum 5 a with the dust sending valves 149, by forming the top plate 124 with such a curve as to substantially follow the rotational path K of the leading ends of the threshing teeth 148 in association with rotation of the

threshing drum 5a, the tlireshing material will be guided smoothly along the inner face of the top plate 124 and the threshing material will be smoothly guided to the rear side as being subjected to the guiding effect of the dust sending valves 149. [0210] Further, downwardly of the threshing drum 5a, the-receiving mesh 117 is provided and the meshes of the receiving mesh 117 have a rectangular shape which is elongated in the rotational direction of the threshing drum 5a. [0211] In the threshing drum 114, a large amount of threshing material will be rotated together with the threshing drum in association with the rotation of this threshing drum 5a. For this, according to the inventive construction above, as the receiving mesh 117 disposed dcv.'nwardly of the threshing drum 5a has a rectangulai shape which is elongate in the rotational direction of the threshing drum 5a, the moving direction of the threshing material rotated in unison with the threshing drum
5a agrees with the direction of the meshes of the recei\ang"lnesirn77 so^hafllTe grains contained in the threshing material will easily drop from the meshes of the receiving mesh 117.
[0212] [Other Embodiments]
In the above, one preferred embodiment of the threshing apparatus according to the present invention has been described with reference to the drawings. The present invention, however, is not limited to this embodiment. For instance, various modifications as follows are possible.
[0213] [1] Instead of the transmission mechanism in the foregoing embodiment, it is possible to employ a further transmission mechanism wherein the case input shaft 37 is adapted to be driven to rotate in the reverse direction and the harvesting output shaft 39 is adapted to be driven to rotate in the forward direction, respectively, the case input shaft 37 and the harvesting input shaft 42 are operably coupled via the reverse rotation clutch and the harvesting output shaft 39 and the harvesting input shaft 42 are operably coupled via the forward rotation clutch or a still farther transmission mechanism wherein both the case input shaft 37 and the harvesting output shaft 39 are disposed on the left side or the right side of the traveling vehicle body, relative to the threshing drum output shaft 39. In these cases too, the objects of the present invention can be achieved.
[0214] [2] Instead of the restraining mechanism 70 employed in the foregoing embodiment, it is possible to embody the invention by employing a further restraining mechanism wherein the restraining member 71 is provided in the reverse rotation clutch operating tool 54 and the contacting portion is provided in the forward

rotation clutch operating tool 52. In this case too, the objects of the present
invention can be achieved.
[0215] [3] The threshing drum 5a can omit the raking-in section 141. Further, in
the raking-in section 141, rectifying teeth or threshing teeth 147 can be provided
instead of the spiral blades 143.
[0216] [4] The threshing drum 5a can be constructed such that round bar steel
members, angular bar steal members, angular pipe steel members, angle members or
channel members are employed as the respective threshing drum frames (bar-like
members) 147.
[0217] [5] Regarding the threshing drum 5a, the number of threshing drum frames
(bar-like members) 147 to be mounted therein can vary. For instance, eight
threshing drum frames 147 can be mounted.
[0218] [6] In the threshing drum 5a, the plurality of^Ereshing''drum^frames^
(bar-like members )147 can be fixed to the respective plates 144-146, to be not
switchable in their orientations.
[0219] [7] All of the threshing teeth 148 mounted to the threshing drum frames
(bar-like members) 147 can be fixedly welded to the threshing drum frames 147 or
can be detachably bolt-cormected to the threshing drum frames 147.
[0220] [8] All of the threshing teeth 148 or some of the threshing teeth 148
mounted to the bar-like members 147 can be formed like blades having a guide face
for guiding the threshing material to the downstream side in the threshing process
direction in association with rotation of the threshing drum 5a. And, the leading end
portions thereof can be bent in the L-shape so as to act as guiding portions for guiding
the threshing material to the downstream side in the threshing process direction in
association with rotation of the threshing drum 5a.
[0221] [9] As the threshing teeth 148, angular bar steal members, round pipe
members or the like can be employed. Or, members bent in the U-shape or V-shape
can be employed also.
[0222] [10] The disposing distance between the threshing teeth 148 can vary in
many ways. For instance, if the number of threshing drum frames (bar-like
members) 147 is set as a multiple of three, the respective threshing teeth 148 may be
arranged with 1/3 pitch displacement in the fore/aft direction relative to the threshing
teeth 148 mounted on the adjacent threshing drum frame 147. Further, if the number
of threshing drum frames (bar-like members) 147 is set as a multiple of four, the
respective threshing teeth 148 may be arranged with 1/4 pitch displacement in the
fore/aft direction relative to the threshing teeth 148 mounted on the adjacent

threshing drum frame 147. Further alternatively, the disposing distances of the threshing teeth 148 may be different from each other in the front side and the rear side, so that the fore/aft distance between the threshing teeth 148 on the rear side is greater than the fore/aft distance between the threshing teeth 148 on the front side. [0223] [11] The partitioning member is not limited to the second plate 45 described in the foregoing embodiment. The construction, shape and the number thereof can vary in many ways. For instance, the partitioning plate may be formed of a circular porous plate. Or, this can be comprised of a plurality of bar-like extension members extending from the harvesting output shaft 38 to the respective bar-like members 47 and an annular interconnecting member for interconnecting the extending ends of the respective extension members. Further alternatively, the partitioning member can be formed as a conical member which progressively extends to the downstream side in the threshing process direction^iTthe o^iiteT^eriplieralTide" thereof, thus providing a function of guiding the threshing material to the periphery of the tlireshing drum 5a. Further alternatively, the threshing drum 5a may be provided with a plurality of partitioning members.
[0224] [12] An air generating device (e.g. a winnowing fan) may be provided solely for generating air flow which flows from the threshing process-wise upstream side of the partitioning member to the threshing process-wise downstream side of the partitioning member.
[0225] [13] All of the dust sending valves 149 or some of the dust sending valves 149 mounted on the top plate 124 may be formed with such a short length not to extend one of the right and left lateral edge portion 124C of both of the right and left lateral edge portions 124C of the top plate 124.
[0226] [14] The dust sending valve 149 may be adapted to be movable for adjusting its opening degree adjustment in accordance with the amount of threshing material present in the threshing chamber 114, so as to further improve the threshing performance and the threshing efficiency.
[0227] [15] The top plate 124 may be constructed such that its curved portion 124A is curved so as to follow the rotational path K of the leading ends of the threshing teeth 148. Or, instead of the curved portion 124A, the top late 124 may include a curved portion which is curved to cover the upper side of the threshing drum 5a from above.
[0228] [16] The threshing drum 5 a can be constructed as the drum type wherein its threshing section 142 includes a cylindrical body portion, two screws mounted on the outer periphery of the body portion to extend continuously with the two spiral blades

143 mounted in the raking-in section 141, a number of threshing teeth detachably
attached with a predetermined distance therebetween to project outwards toward the
outer peripheral portions ofthe respective screws, etc.
[0229] [17] The threshing drum 5z can be constructed such that a single spiral
blade 143 is detachably attached to the outer peripheral face ofthe raking-in section
141 provided at its front end portion or that three or more spiral blades 143 are
detachably attached to the outer peripheral face of this raking-in section 141.
[0230] [18] The threshing drum 5a can be constructed such that a plurality of
support metal members to which the spiral blades 143 are detachably attached are
arranged in the spiral pattern on the outer peripheral face of its front end portion
(raking-in section 141).
[0231] [19] As the spiral blade 143, a plurality of spiral blades may be arranged in
the spiral pattern on the outer peripheral face ofthFthreshih^"dmnrtfrarendrportroir"
(raking-in section 141).
[0232] [20] The conveyance assisting guide 151 can be adapted to be dividable
between right and left sections or into three or more sections.
[0233] [21] The conveyance assisting guide 151 maybe constructed such that only
its portion 15IB located on the downstream side in the rotational direction of the
threshing drum 5a is detachably attached.
[0234] [22] The conveyance assisting guide 151 may be formed not of stainless
steel, but of other steel material such as carbon steel.
[0235] [23] The join member 150 can be adapted to be detachably attached to the
receiving mesh 117.
[0236] [24] Lastly, the threshing apparatus can be other than the illustrated
whole-culm charging type combine, but a culm-head charging type combine wherein
only culm heads of harvested culms are charged into the threshing chamber 114.
Industrial Applicability
[0237] As described above, the present invention is applicable to a combine having a threshing apparatus (a whole-culm charging type combine and a culm-head charging type combine).

CLAIMS
[1] A combine including a threshing apparatus having a threshing drum; an engine mounted on a traveling vehicle body; and a harvesting section provided it a front portion of the threshing apparatus,
wherein on the front side of the threshing apparatus, there is provided a power transmission case which mounts a case input shaft for receiving a drive force from the engine, and a fore/aft oriented threshing drum output shaft operably coupled with the case input shaft via a bevel gear mechanism;
said power transmission case further mounts a harvesting output shaft operably coupled with the case input shaft via the bevel gear mechanism so as to be driven in a rotational direction reverse to a rotational direction of the case input shaft;
there is provided a forward case input shaft and said harvesting output shaft with said harvesting input shaft so as to transmit drive force in the forward rotational direction to a harvesting input shaft of the harvesting section; and
there is provided a reverse rotation clutch for operably coupling the other of said case input shaft and said harvesting output shaft with said harvesting input shaft so as to transmit drive force in the reverse rotational direction to the harvesting input shaft of the harvesting section.
[2] The combine according to claim 1, wherein said case input shaft and said harvesting output shaft are juxtaposed along the transverse direction of the traveling vehicle body across said threshing drum output shaft.
[3] The combine according to claim 1, wherein said reverse rotation clutch is maintained under the engaged condition by a manual operation.
[4] The combine according to any one of claims 1-3, further comprising:
a forward rotation clutch operating tool for switching over the forward
rotation clutch;
a reverse rotation clutch operating tool for switching over the reverse
rotation clutch, said forward rotation clutch and said reverse rotation clutch being
provided separately of one another; and
a restraining mechanism which is switched over into an active condition for
restraining switchover of the reverse rotation clutch to the engaged condition when
c/i

the forward rotation clutch is under the engaged condition and which is switched over into a releasing condition for releasing the restraint when the forward rotation clutch is under the disengaged condition.
[5] A combine including a threshing apparatus having a threshing drum; an engine mounted on a traveling vehicle body; and a harvesting section provided at a front portion of the threshing apparatus, comprising:
a forward rotation clutch for transmitting a forward rotational drive force to the harvesting section;
?. reverse rotation clutch for transmitting a reverse rotational drive force to the harvesting section;
a forward rotation clutch operating tool for switching over the forward rotation clutch; a reverse rotation clutch operating tool for switching over the reverse rotation clutch;
said forward rotation clutch and said reverse rotation clutch being provided separately of one another; and
a restraining mechanism which is switched over into an active condition for restraining switchover of the reverse rotation clutch to the engaged condition when the forward rotation clutch is under the engaged condition and which is switched over into a releasing condition for releasing the restraint when the forward rotation clutch is under the disengaged condition.
[6] The combine according to claim 5, wherein said restraining mechanism is configured such that the switchover of the reverse rotation clutch into the engaged condition is restrained as a restraining member supported to one of the forward rotation clutch operating tool and the reverse rotation clutch operating tool to be pivotable therewith comes into contact with a contacting portion provided in the other of the forward rotation clutch operating tool and the reverse rotation clutch operating tool, thereby to restrict the switchover of the reverse rotation clutch to the engaged condition.
[7] A threshing apparatus to be mounted on a combine, comprising:
a threshing drum driven to rotate about a support shaft for effecting a
threshing operation on harvested culm fed into a threshing chamber;
wherein said threshing drum includes a plurality of bar-like members
<;<;

juxtaposed with a predetermined spacing therebetween in the peripheral direction of the threshing drum under a posture along the support shaft, support members provided forwardly and rearwardly of the support shaft so as to support the bar-like members, and ■=, plurality of threshing teeth juxtaposed with a predetermined spacing, therebetween in the fore/aft direction under a posture projecting from the bar-like members to the outside of the threshing drum.
[8] The threshing apparatus according to claim 7, wherein the threshing drum is provided with a partitioning member for partitioning its inner space between the front and rear sides.
[9] The threshing apparatus according to claim 8, wherein there is provided a

sorting air flow from the winnowing fan is caused to flow toward the partitioning
member.
[10] The threshing apparatus according to claim 7, wherein the upper side of the threshing drum is covered with a top plate and this top plate mounts a plurality of dust sending valves for sending harvested culms to the downstream in the threshing process direction in association with rotational drive of the threshing drum.
[11] The threshing apparatus according to claim 10, wherein each of the dust sending valves is formed with such a length as to extend between the right and left side edges of the top plate
[12] The threshing apparatus according to claim 10, wherein the top plate is curved so as to substantially follow a rotational path of the leading ends of the threshing teeth in association with rotation of the threshing drum.
[13] The threshing apparatus according to claim 7, wherein at the front end of the threshing drum, there is mounted a spiral blade for raking in and conveying the harvested culms fed and conveyed toward this front end to the rear side in association with rotation of the threshing drum; and
the spiral blade is detachably attached.
[14] The threshing apparatus according to claim 13, wherein a conveyance
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assisting guide is provided downwardly of the threshing drum in such a manner as to cover the front end of the threshing drum from under, the conveyance assisting guide receiving harvested culm which has been fed and conveyed toward the front end of the threshing drum and assisting the conveyance of the, harvested culm by the spiral blade; and
at least a portion of the conveyance assisting guide which portion is located on the downstream side in the rotational direction of the threshing drum is configured to be detachably attachable.
[15] The threshing apparatus according to claim 7, wherein
a receiving mesh is disposed so as to cover the threshing drum from under; a top plate is disposed so as to cover the threshing drum from above, and

there is detachably mounted a join member configured to have a guide face
for continuously bridging inner faces of the receiving mesh and the top plate.

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