[Title of the Invention]

SEEDLING BOX CONVEYER

[Technical Field]

[0001]
The present invention relates to a seedling box conveyer comprising a conveyer frame, a plurality of endless conveyer belts drivably and rotatably supported to the conveyer frame and juxtaposed with a predetermined distance therebetween in a direction normal to a seedling box conveying direction, a starting end support shaft around which conveyance starting ends of the plurality of endless conveyer belts are wound and a terminating end support shaft around which conveyance terminating ends of the plurality of endless conveyer belts are wound, the seedling box conveyer being configured to receive from under and convey a seedling box by the endless conveyer belts.

[Background Art]

[0002]
As an example of seedling box conveyer of the above noted type, one is known from e.g. Japanese Patent Application "Kokai" No. 2002-233249 (paragraph [00ll], Figs. 3, 4, 5). In the conveyer disclosed in Japanese Patent Application "Kokai" No. 2002-233249, a main frame (corresponding to "a conveyer frame") supports drive shafts and front and rear rotational shafts and on the opposed ends of these shafts, there are provided pulleys around which belts (corresponding to the "endless conveyer belts") are wound. As the belts are driven by a drive force of a motor, a seedling box mounted on the belts is conveyed.

[Summary of the Invention]

Problem To Be Solved By Invention]

[0003]
With the seedling box conveyer described above, if the forward sides of the belts sag due to the load of the seedling box mounted thereon, this tends to invite a problem in the conveyance of the seedling box. Further, the above situation tends to invite a further problem of the seedling box being tilted to cause displacement of seedbed soil within the seedling box.

[0004]
The object of the present invention is to provide a seedling box conveyer capable of preventing such sagging of the endless conveyer belt at low costs and capable of achieving superior durability.

[Means To Solve Problem]

[0005] A seedling box conveyer, according to the present invention, comprises:
a conveyer frames

a plurality of endless conveyer belts drivably and rotatably supported to the conveyer frame and juxtaposed with a predetermined distance therebetween in a direction normal to a seedling box conveying direction;

a starting end support shaft around which conveyance starting ends of the plurality of endless conveyer belts are wound; and

a terminating end support shaft around which conveyance terminating ends of the plurality of endless conveyer belts are wound,

the seedling box conveyer being configured to receive from under and convey a seedling box by the endless conveyer belts;

wherein the seedling box conveyer comprises a supporting means for receiving and supporting from under the forward sides of the plurality of endless conveyer belts between the starting end support shaft and the terminating end support shaft'

said supporting means includes a support shaft fixed to the conveyer frame in the direction normal to the seedling box conveying direction and a cylindrical body rotatably outwardly engaged and rotatably supported on the support shaft and receiving the endless conveyer belts, the cylindrical body being outwardly engaged on the support shaft with inner peripheral face of the cylindrical body being in direct contact with an outer peripheral face of the support shaft.

[0006]
With the above construction, as the cylindrical body is being rotated by the rotational force applied thereto through its contact with the forward side of each endless conveyer belt, the cylindrical body provides a receiving function to the forward side of each endless conveyer belt. Hence, the construction reduces the possibility of generation of frictional wear of the endless conveyer belt and the cylindrical body due to contact between each. endless conveyer belt and the cylindrical body, and also as the forward side of each endless conveyer belt is supported by the support shaft via the cylindrical body, sagging of the forward side of each endless conveyer belt due to the load of the seedling box can be effectively avoided. And, these advantageous effects can be provided with the simple construction of fixing the support shaft to the conveyer frame and directly and outwardly engaging the cylindrical body on this support shaft.

[0007]
Therefore, with the simple construction of fixing the support shaft to the conveyer frame and directly and outwardly engaging the cylindrical body on this support shaft, there can be provided a high-quality seedling box conveyer at low costs and having superior durability, with which the sagging of the forward side of each endless conveyer belt is prevented so that the seedling box can be conveyed in a smooth manner with less possibility of inadvertent change such as tilting in the posture of the seedling box and frictional wear of the endless conveyer belts and the cylindrical body is less likely to occur so that the conveyer may be used for an extended period of time.

[0008]
Alternatively, a seedling box conveyer, according to the present invention, comprises:

a conveyer frame,'

a plurality of endless conveyer belts drivably and rotatably supported to the conveyer frame and juxtaposed with a predetermined distance therebetween in a direction normal to a seedling box conveying direction,’

a starting end support shaft around which conveyance starting ends of the plurality of endless conveyer belts are wound; and

a terminating end support shaft around which conveyance terminating ends of the plurality of endless conveyer belts are wound, the seedling box conveyer being configured to receive from under and convey a seedling box by the endless conveyer belts;

wherein the seedling box conveyer comprises a supporting means for receiving and supporting from under the forward sides of the plurality of endless conveyer belts between the starting end support shaft and the terminating end support shaft;

said supporting means includes a support shaft fixed to the conveyer frame in the direction normal to the seedling box conveying direction and a plurality of cylindrical bodies rotatably outwardly engaged and rotatably supported on the support shaft and receiving the endless conveyer belts respectively, the cylindrical bodies being outwardly engaged on the support shaft, with inner peripheral faces of the cylindrical bodies being in direct contact with an outer peripheral face of the support shaft.

[0009]
With the above construction, as the cylindrical body is being rotated by the rotational force applied thereto through its contact with the forward side of each endless conveyer belt, the cylindrical body provides a receiving function to the forward side of each endless conveyer belt. Hence, the construction reduces the possibility of generation of frictional wear of the endless conveyer belt and the cylindrical body due to contact between each endless conveyer belt and the cylindrical body and also as the forward side of each endless conveyer belt is supported by the cylindrical bodies, sagging of the forward side of each endless conveyer belt due to the load of the seedling box can be effectively avoided. The cylindrical body can only be a short cylindrical body enough to provide the receiving function only to the corresponding endless conveyer belt of the plurality of endless conveyer belts. And, the rotational resistance to the cylindrical body generated due to the contact between the cylindrical body and the endless conveyer belt is minimized, so that the rotation of the cylindrical body due to its contact with the endless conveyer belt can occur in a smooth manner. And, these advantageous effects can be provided with the simple construction of fixing the support shaft to the conveyer frame and directly and outwardly engaging the cylindrical bodies on this support shaft.

[0010]
With the above-described construction, if frictional wear has occurred in one or some of the cylindrical bodies due to the contact thereof with the endless conveyer belts, by replacing only the worn-out cylindrical body (bodies) with leaving the non-worn ones, the supporting means can be restored to the predetermined working condition.

[0011]
Therefore, with the simple construction of fixing the support shaft to the conveyer frame and directly and outwardly engaging the cylindrical bodies on this support shaft, there can be provided a high-quality seedling box conveyer at low costs and having superior durability, with which the sagging of the forward side of each endless conveyer belt is prevented so that the seedling box can be conveyed in a smooth manner with less possibility of inadvertent change such as tilting in the posture of the seedling box, and frictional wear of the endless conveyer belts and the cylindrical bodies is less likely to occur so that the conveyer may be used for an extended period of time.
Moreover, if frictional wear has occurred in one or some of the cylindrical bodies due to the contact thereof with the endless conveyer belt(s), by replacing only the worn-out cylindrical body (bodies) with leaving the non-worn ones, the supporting means can be restored to the predetermined working condition at low costs.

[0012]
Preferably, a portion of the cylindrical body receiving the forward side of the endless belt is offset to one side toward one terminating end of the cylindrical body relative to the axial center of the cylindrical body.

[0013]
With the above-described construction, even if there occurs frictional wear at the portion of the cylindrical body receiving the forward side of the endless belt, this cylindrical body can be revised.
That is, by appropriately setting the distance of the offset of the endless conveyer belt receiving portion of the cylindrical body relative to the axial center of the cylindrical body, if there occurs frictional wear at this endless conveyer belt receiving portion of the cylindrical body due to the contact with the endless belt, the attaching orientation of the cylindrical body relative to the support shaft may be changed such that one terminating end of the cylindrical body which was located on the left side of the endless conveyer belt prior to the occurrence of the frictional wear is moved to the right side of the endless conveyer belt. With this, the worn-out portion may be removed from the forward side of the endless conveyer belt and the portion which was unused as being off the forward side of the endless belt conveyer prior to the attaching orientation change may now be placed to face the forward side of the endless conveyer belt to function as a new portion for receiving the endless conveyer belt.

[0014]
Therefore, if there occurs frictional wear at this endless conveyer belt receiving portion of the cylindrical body due to the contact with the endless belt, this cylindrical body can be reused for receiving the forward side of the endless conveyer belt, without requiring a new cylindrical body. Hence, as a whole, there can be obtained a seedling box conveyer which can be used inexpensively for an extended period of time.

[0015]
Preferably, there is provided a positioning cylindrical body disposed between a pair of cylindrical bodies for respectively receiving a pair of endless conveyer belts of the plurality of endless conveyer belts, said positioning cylindrical body contacting end faces of said pair of cylindrical bodies so as to fix these paired cylindrical bodies in position for receiving the endless conveyer belts, and
said paired cylindrical bodies and said positioning cylindrical body have identical specifications such that said paired cylindrical bodies may be attached to said support shaft as positioning means as a substitute for said positioning cylindrical body and said positioning cylindrical body may be attached to said support shaft as receiving means as a substitute for said paired cylindrical bodies. [0016]
With the above-described construction, if there occurs functional wear in a cylindrical body due to the contact with the endless belt, in place of this cylindrical body, the positioning cylindrical body may be caused to support the forward side of the endless conveyer belt.
That is, if functional wear occurs in a cylindrical body due to its contact with the endless conveyer belt, this cylindrical body may be attached to the support shaft at the position between the cylindrical bodies which position was occupied previously by the positioning cylindrical body, whereas the positioning cylindrical body may be attached to the support shaft at the position which was occupied previously by the cylindrical body in replacement there for. With these, the positioning cylindrical body is located so as to provide the receiving action to the forward side of the endless conveyer belt and is fixed at this position by the cylindrical body. [0017]
Therefore, even if there occurs frictional wear in a cylindrical body due to its contact with the endless conveyer belt, the positioning cylindrical body may be used in place of this cylindrical body for receiving and supporting the forward side of the endless conveyer belt. Thus, a new cylindrical body is not needed, and there can be obtained a superior seedling box conveyer as a whole that can be used inexpensively for an extended period of time.

[0018]
Preferably, the axis of the cylindrical body is offset relative to the axis of the support shaft, with an outer peripheral face of the support shaft being in point-contact with an inner peripheral face of the cylindrical body as seen in the direction along the axis of the support shaft.

[0019]
With the above-described construction, rotational resistance of the cylindrical body which occurs due to the contact between the cylindrical body and the support shaft is minimized, so that the rotation of the cylindrical body due to its contact with the endless conveyer belt may proceed smoothly, whereby frictional wear of the endless conveyer belt and the cylindrical body may be less likely to occur.

[0020]
Accordingly, there can be obtained a seedling box conveyer having superior durability that can be used for an extended period of time, with further increased service life of the endless conveyer belt and the cylindrical body.
[Brief Description of the Drawings]

[0021]
Fig. 1 is a front view showing the entirety of a seedling plant,
Fig. 2 is a plane view showing the entirety of the seedling plant,
Fig. 3 is a plane view showing portions of a conveyer where a posture
determining guide plate and a first supplying guide plate are provided,
Fig. 4 (a) is a front view showing a lowered used condition of a first
seedling box conveyer,
Fig. 4 (b) is a front view showing an elevated folded condition of the first
seedling conveyer,
Fig. 5 is a side view in vertical section showing supporting means, Fig. 6 is a fix)nt view in vertical section showing the supporting means, Fig. 7 is a side view in vertical section showing a condition where a
cylindrical body and a positioning cylindrical body of the supporting means are
replaced with each other,
Fig. 8 is a front view in vertical section showing a seedbed soil supplying
device,
Fig. 9 is a side view in vertical section showing the seedbed soil supplying
device,
Fig. 10 is side view showing a brush height adjusting mechanism,
Fig. 11 is a plane view showing the brush height adjusting mechanism,
Fig. 12 is a front view showing an adjusting shaft,
Fig. 13 is a front view showing a support construction of a leveling brush,
Fig. 14 is a diagram showing the construction of a transmission
mechanism in its front view,
Fig. 15 is a plane view showing the transmission mechanism,
Fig. 16 is a side view showing a portion where a motor is disposed,
Fig. 17 is a front view showing a supply drive mechanism,
Fig. 18 is a perspective view showing a connection changing mechanism,
Fig. 19 is a perspective view showing a motor mount connection changing
mechanism,
Fig. 20 is a side view in vertical section showing supporting means
provided in a first alternative embodiment,
Fig. 21 is a side view in vertical section showing supporting means
provided in a second alternative embodiment, and
Fig. 22 is a side view in vertical section showing supporting means
provided in a third alternative embodiment.
[Modes of Embodying the Invention]

[0022]
Next, embodiments of the present invention will be described with reference to the accompanying drawings. [0023]
Fig. 1 is a front view showing the entirety of a seedling plant relating to an embodiment of the present invention. Fig. 2 is a plane view showing the entirety of the seedling plant. As shown in these figures, the seedling plant relating to this embodiment of the present invention comprises a conveyer apparatus C including a first seedling box conveyer 10 constituting a conveyance starting end portion and a seedling box mount 1 connected to the conveyance terminating end portion, and a seedbed soil supplying device 40, an irrigating device 50, a sowing device 60 and a cover soil supplying device 70 which are juxtaposed along a seedling box conveying direction of this conveyer apparatus C. [0024]
With this seedling plant in operation, after a seedling box 2 is mounted at the conveyance starting end portion of the conveyer apparatus C, this seedling box 2 is conveyed and supplied by the conveyer device C to the seedbed soil supplying device 40, the irrigating device 50, the sowing device 60 and the cover soil supplying device 70 one after another. In the course of this, a sowing operation is effected as follows. Namely, an amount of chaff smoked charcoal (charred material obtained by smoking treatment of rice husk or chaff is supplied as seedbed soil to form a seedbed soil portion. An amount of irrigating water is supplied onto the formed seedbed soil portion. And, onto the irrigated seedbed soil portion, an amount of seed rice is fed by sprinkling. And, onto the seedbed soil portion after the seed rice supplying, another amount of chaff smoked charcoal is supplied as a cover soil material to form a cover soil portion. The seedling box 2 after completion of the sowing operation is placed on the seedling box mount 1.
[0025]
Next, the conveyer apparatus C will be described in details.
[0026]
The conveyer apparatus C includes the first seedling box conveyer 10 constituting the conveyance starting end portion of the conveyer apparatus C, a second seedling box conveyer 20 connected continuously to the conveyance terminating end of the first seedling box conveyer 10, and a third seedling box conveyer 30 connected continuously to the conveyance terminating end of the second seedling box conveyer 20.
[0027]
The conveying distance of the seedling box 2 by the conveyer apparatus C is set as follows.
The seedling box 2 is mounted on the conveyer apparatus C such that the short side of the long and short sides of the seedling box 2 is aligned with the seedling box conveying direction. The posture of the seedling box 2 as mounted on the conveyer apparatus C in the manner above is set as the conveying posture of the seedling box 2. If a problem is found with the seedling box 2 being conveyed from the seedbed soil supplying device 40 to the irrigating device 50, such as displacement or supplying deficiency of the seedbed soil portion, it is made possible to remove the seedling box 2 from a gap Dl formed between a leveling brush 41 provided in the seedbed soil supplying device 40 and a machine frame 51 of the irrigating device 50. Further, if a problem is found in the seedling box 2 being conveyed from the irrigating device 50 to the sowing device 60 such as displacement of the seedbed soil portion, the seedling box 2 can be taken out from a gap D2 between the machine frame 51 of the irrigating device 50 and a seed tank 61 of the sowing device 60. Further, an arrangement is made in conveying the seedling box 2 from the irrigating device 50 to the sowing device 60 such that this conveying operation takes such a length of time that an amount of irrigating water supplied by the irrigating device 50 has already soaked in the seedbed soil portion and no amount of the irrigating water is present over the upper surface of the seedbed soil portion. On some occasions, when requested, a medical agent supplying device (not shown) may be additionally provided between the sowing device 60 and the cover soil supplying device 70. So, a gap D3 between the seed tank 61 of the sowing device 60 and a cover soil tank 71 of the cover soil supplying device 70 is set to such a size as to allow disposing of the medical agent supplying device. That is to say, the conveyer apparatus C is provided with such conveying distance as taking into consideration, such factors as the length of the short side of the seedling box 2, the removal of the seedling box 2, soaking and permeation of the irrigating water in the seedbed soil portion, the additional disposing of the medical agent supplying device.
[0028]
As shown in Fig. 1 and Fig. 2, the first seedling box conveyer 10 includes a conveyer frame 11 whose end on the downstream side of the seedling box conveying direction is connected to the upstream side of the seedling box conveying direction of a conveyer frame 21 of the second seedling conveyer 20, and a pair of right and left endless belts 12,12 drivably and rotatably supported to this conveyer frame 11 in juxtaposition with a predetermined distance therebetween in the direction normal to the seedling box conveying direction.
[0029]
The conveyer frame 11 of the first seedling box conveyer 10 comprises a pair of right and left main frames 11a, 11a distributed to the left side and the right side ends of the first seedling box conveyer 10 in the direction normal to the seedling box conveying direction. The pair of right and left endless conveyer belts 12, 12 of the first seedling box conveyer 10 are wound around starting end side pulleys 14 mounted on a starting end side support shaft 13 to be rotatable in unison therewith, the shaft 13 being rotatably supported to conveyance starting ends of the pair of right and left main frames 11a, 11a, and terminating end side pulleys 15 mounted on a starting end side support shaft 22 to be rotatable in unison therewith, the shaft 22 being rotatably supported to conveyance starting end of the conveyer frame 21 of the second seedling box conveyer frame 21.

[0030]
Therefore, with the first seedling box conveyer 10 in operation, as the starting end side support shaft 22 of the second seedling box conveyer 20 is driven, the pair of right and left endless conveyer belts 12, 12 are driven by the terminating end side pulleys 15, whereby the seedling box 2 mounted thereon is received from under and conveyed by the forward sides of the pair of right and left endless conveyer belts 12,12 to the second seedling box conveyer 20.
[0031]
As shown in Fig. 1 and Fig. 2, the conveyer frame 21 of the second seedling box conveyer 20 includes the conveyer frame 21 mounting a pair of front and rear stands 23, 23 juxtaposed along the seedling box conveying direction and a pair of right and left endless conveyer belts 24, 24 drivably and rotatably supported to this conveyer frame 21 with a predetermined distance therebetween in the direction normal to the seedling box conveying direction.
[0032]
The conveyer frame 21 of the second seedling box conveyer 20 comprises a pair of right and left main frames 21a, 21a distributed to the left side and the right side ends of the second seedling box conveyer 20 in the direction normal to the seedling box conveying direction. The pair of right and left endless conveyer belts 24, 24 of the second seedling box conveyer 20 are wound around starting end side pulleys 25 mounted on the starting end side support shaft 22 to be rotatable in unison therewith, the shaft 22 being rotatably supported to conveyance starting ends of the pair of right and left main frames 21a, 21a, and terminating end side pulleys 27 mounted on a drive shaft 26 to be rotatable in unison therewith, the shaft 26 being rotatably supported to conveyance terminating ends of the pair of right and left main frames 21a, 21a: on more downstream side in the seedling conveying direction than the irrigating device 50. [0033]
Therefore, with the second seedling box conveyer 20 in operation, as the drive shaft 26 is driven, the pair of right and left endless conveyer belts 24, 24 are driven by the terminating end side pulleys 27, and the seedling box 2 which has been delivered by the first seedling box conveyer 10 is received from under and conveyed by the forward sides of the pair of right and left endless conveyer belts 24, 24 to the seedbed soil supplying device 40. Then, the seedbed soil supplying device 40 supplies an amount of chaff smoked charcoal as seedbed soil. The seedling box 2 after the supply of chaff smoked charcoal as seedbed soil by the seedbed soil supplying device 40, is then supplied to the irrigating device 50. Then, the seedling box 2 after supply of irrigating water by the irrigating device 5 is conveyed to the third seedling box conveyer 30.
[0034]
As shown in Fig. 1 and Fig. 2, the third seedling box conveyer 30 comprises a conveyer frame 32 mounting a pair of front and rear stands 31, 31 juxtaposed in the seedling conveying direction and a pak of right and left endless conveyer belts 33, 33 drivably and rotatably supported to this conveyer frame 32 and juxtaposed with a predetermined distance therebetween in the direction normal to the seedling box conveying direction.

[0035]
The conveyer frame 32 of the third seedling box conveyer 30 includes a pair of right and left main frames 32a, 32a distributed on the left end and the right end of the third seedling box conveyer 30 in the direction normal to the seedling box conveying direction. The pair of right and left endless conveyer belts 33, 33 of the third seedling box conveyer 30 are wound around starting end side pulleys 35 mounted on the starting end side support shaft 34 to be rotatable in unison therewith, the shaft 34 being rotatably supported to conveyance starting ends of the pair of right and left main frames 32a, 32a, and terminating end side pulleys 37, 37 mounted on a drive shaft 36 to be rotatable in unison therewith, the shaft 36 being rotatably supported to conveyance terminating ends of the pair of right and left main frames 32a, 32a on more downstream side in the seedling conveying direction than the cover soil supplying device 70.
[0036]
Therefore, with the third seedling box conveyer 30 in operation, as the drive shaft 36 is driven, the pair of right and left endless conveyer belts 33, 33 are driven by the terminating end side pulleys 37, and the seedling box 2 which has been delivered by the second seedling box conveyer 20 is received from under and conveyed by the forward sides of the pair of right and left endless conveyer belts 33, 33 to the sowing device 60. Then, the sowing device 60 supplies seeds. Then, the seedling box 2 after supply of seeds by the sowing device 60 is conveyed to the cover soil supplying device 70. Then, the seedling box 2 after supply of an amount of chaff smoked charcoal as the cover soil by the cover soil supplying device 70 is conveyed to the seedling box mount 1.

[0037]
The seedling box mount 1 includes a pair of right and left main mount frames la, la having one end sides thereof connected to the seedling box conveying downstream end of the conveyer frame 32 of the third seedling box conveyer 30 and transverse beams Ib juxtaposed in the seedling box conveying direction with a predetermined distance therebetween and connected to the right and left main mount frames la, la. In operation, the seedling box 2 from the third seedling box conveyer 30 after completion of the sowing operation is received and supported by the transverse beams Ib.
[0038]
The conveyer apparatus C includes a posture determining guide plate 3 disposed at one end side of the first seedling box conveyer 10 in the direction normal to the seedling box conveying direction and supported to the conveyer frame 11 of the first seedling box conveyer 10, a pair of right and left first supplying guide plates 4, 4 disposed in distribution on the lateral opposed sides in the direction normal to the seedling box conveying direction at the entrance of the first seedbed soil supplying device 40 and supported to the conveyer frame 21 of the second seedling box conveyer 20, and a pair of right and left second supplying guide plates 5, 5 disposed in distribution on the lateral opposed sides in the direction normal to the seedling box conveying direction at positions slightly more distant on the downstream side in the seedling box conveying direction than the leveling brush 41 provided in the seedbed soil supplying device 40.
[0039]
The conveyer apparatus C further includes a pair of right and left third supplying guide plates 6, 6 provided at the entrance of the sowing device 60 in distribution on the opposed lateral sides in the direction normal to the seedling box conveying direction and supported to the conveyer frame 32 of the third seedling box conveyer 30, and a pair of right and left fourth supplying guide plates 7, 7 provided at the entrance of the cover soil supplying device 70 in distribution on the opposed lateral sides in the direction normal to the seedling box conveying direction and supported to the conveyer frame 32 of the third seedling box conveyer 30.

[0040]
As shown in Fig. 3, with the posture determining guide plate 3 disposed in the first seedling box conveyer 10 in operation, the seedling box 2 is mounted on the first seedling box conveyer 10, with an outer side of the lateral wall of the seedling box 2 located on the short side thereof being placed in abutment against a working face of the posture determining guide plate 3 located on the inner side of the conveyer. With this, the seedling box 2 mounted on the first seedling box conveyer 10 is fixed in posture to the predetermined conveying posture by the work face.

[0041]
Referring to the function of the pair of right and left first supplying guide plates 4, 4 disposed in the second seedling box conveyer 20, if the seeding box 2 delivered from the first seedling conveyer 10 to the second seedling conveyer 20 suffers disturbance in its conveying posture due to e.g. connecting of the conveyer frames 11, 21 of the first seedling conveyer 10 and the second seedling conveyer 20, an end portion of the seedling box 2 delivered to the seedbed soil supplying device 10 comes into contact and shding contact with the work face of the first supplying guide plate 4, whereby the posture of the second seedling box 2 delivered to the seedbed soil supplying device 40 is corrected to the predetermined conveying posture.

[0042]
As shown in Fig. 2, referring to the function of the pair of right and left second supplying guide plates 5, 5 disposed in the second seedling box conveyer 20, if the seeding box 2 delivered from the seedbed soil supplying device 40 suffers disturbance in its conveying posture due to the function of the leveling brush 41, an end portion of the seedling box 2 delivered to the irrigating device 50 comes into contact and sliding contact with the work face of the second supplying guide plate 5, whereby the posture of the second seedling box 2 to be delivered to the irrigating device 50 is corrected to the predetermined conveying posture.
[0043]
Referring to the function of the pak of right and left third supplying guide plates 6, 6 disposed in the third seedling box conveyer 30, if the seeding box 2 delivered from the second seedling box conveyer 20 to the third seedling box conveyer 30 suffers disturbance in its conveying posture due e.g. to the connection of the conveyer frames 21, 32 of the second seedling conveyer 20 and the third seedling conveyer 30, an end portion of the seedling box 2 to be delivered to the sowing device 60 comes into contact and sliding contact with the work face of the third supplying guide plate 6, whereby the posture of the second seedling box 2 to be delivered to the sowing device 60 is corrected to the predetermined conveying posture.

[0044]
Referring to the function of the pair of right and left fourth supplying guide plates 7, 7 disposed in the third seedling box conveyer 30, if the seeding box 2 delivered from the sowing device 60 suffers disturbance in its conveying posture due e.g. to swaying of the endless conveyer belts 33, when this seedling box 2 is sent to the cover soil supplying device 70, an end portion of the seedling box 2 comes into contact and sliding contact with the work face of the fourth supplying guide plate 7, whereby the posture of the second seedling box 2 to be delivered to the cover soil supplying device 70 is corrected to the predetermined conveying posture.

[0045]
The posture determining guide plate 3, the first supplying guide plates 4, the second supplying guide plates 5, the supplying guide plates 6, and the fourth supplying guide plate 4 each provides position adjustment in the direction normal to the seedling box conveying direction through utilization of an elongate shape of attaching bolt holes. Further, the first supplying guide plates 4, the second supplying guide plates 5, the third supplying guide plates 6, and the fourth supplying guide plate 7 each includes an inclined introducing face provided at the starting end with an inclination relative to the seedling box conveying direction.

[0046]
The first seedling box conveyer 10 denoted with the solid line in Fig. 1 illustrates its lowered used condition. Fig. 4 (a) is a front view showing the first seedling box conveyer 10 under the lowered used condition. The first seedling box conveyer 10 denoted with the two-dot chain line in Fig. 1 illustrates its elevated folded condition. Fig. 4 (b) is a front view showing the first seedling box conveyer 10 under this elevated folded condition. As shown in these figures, the first seedling box conveyer 10 is switched over between the elevated folded condition and the lowered used condition as the conveyer frame 11 of the first seedling box conveyer 10 is vertically pivoted about an axis P interconnecting the conveyer frame 11 of the first seedling conveyer 10 and the conveyer frame 21 of the second seedling box conveyer 20 via fasteners 11b, 21b. In the course of the switchover of the first seedling box conveyer 10 between the elevated folded condition and the lowered used condition, as the axis P about which the conveyer frame 11 of the first seedling conveyer 10 is pivoted differs from the axis of the starting end side support shaft 22 of the second seedling box conveyer 20 about which the conveyance terminating end sides of the pair of right and left endless conveyer belts 12 of the first seedling box conveyer 10 are wound, as shown in Fig. 4 (b), the starting end side support shaft 13 about which the conveyance starting end portions of the pair of right and left endless conveyer belts 12, 12 of the first seedling box conveyer 10 are wound is slightly moved and adjusted toward the conveyance terminating end side, whereby the pair of right and left endless conveyer belts 12, 12 are switched over to a condition slightly slacked from the used condition. The moving adjustment of the starting end side support shaft 13 is effected through utilization of the elongate shape of shaft holes 16 formed in the pair of right and left main frames 11a, 11a to allow the starting end side support shaft 13 to extend there through.

[0047]
The seedling box mount 1 shown with the two-dot chain like in Fig. 1 shows its elevated folded condition. The seedling box mount 1 shown with the solid line in Fig. 1 shows its lowered used condition. As shown in these figures, this seedling box mount 1 is switched over between the elevated folded condition and the lowered used condition as the table is vertically pivoted about an axis interconnecting the main table frame la of the seedling box mount 1 and the conveyer frame 32 of the third seedling box conveyer 30.

[0048]
Therefore, with the seedling plant in operation, at the time of conveyance, as the first seedling conveyer 10 and the seedling box mount 1 are switched over to the elevated folded condition, the dimension of the plant formed by the conveyer apparatus C in the seedling box conveying direction is reduced relative to that under the used condition, so that the plant can be accommodated in a container advantageously.
[0049]
The first seedling box conveyer 10 includes a plurality of supporting means 80 disposed between the starting end side support shaft 13 about which the conveyance starting ends of the pair of right and left endless conveyer belts 12, 12 thereof are wound and the starting end side support shaft 22 of the second seedling box conveyer 20 about which conveyance terminating ends of the pair of right and left endless conveyer belts 12, 12 are wound, and disposed with a predetermined distance with each other in the seedling box conveying direction.
[0050]
The second seedling box conveyer 20 includes a plurality of supporting means 80 disposed between the starting end side support shaft 22 about which the conveyance starting ends of the pair of right and left endless conveyer belts 24, 24 thereof are wound and the drive shaft 26 as the terminating end side support shaft about which conveyance terminating ends of the pair of right and left endless

conveyer belts 24, 24 are wound, and disposed with a predetermined distance with
each other in the seedling box conveying direction.
[0051]
The third seedling box conveyer 30 includes a plurality of supporting means 80 disposed between the starting end side support shaft 34 about which the conveyance starting ends of the pair of right and left endless conveyer belts 33, 33 thereof are wound and the drive shaft 36 as the terminating end side support shaft about which conveyance terminating ends of the pair of right and left endless conveyer belts 33, 33 are wound, and disposed with a predetermined distance with each other in the seedling box conveying direction. [0052]
Fig. 5 is a side view in vertical section showing the supporting means 80 included in the first seedling box conveyer 10, the second seedling box conveyer 20 and the third seedling box conveyer 30, respectively. Fig. 6 is a front view in vertical section showing the supporting means 80 included in the first seedling box conveyer 10, the second seedling box conveyer 20 and the third seedling box conveyer 30, respectively. As shown in these figures, the supporting means 80 included respectively in the first seedling box conveyer 10, the second seedling box conveyer 20 and the third seedling box conveyer 30 includes a support shaft 82 disposed along the direction normal to the seedling box conveying direction and fixed to the pair of right and left main frames 11a, 11a or 21a, 21a or 32a, 32a of the conveyer frame 11 or 21 or 32 of the first seedling box conveyer 10 or the second seedling box conveyer 20 or the third seedling box conveyer 30, a pair of cylindrical bodies 83, 83 disposed in distribution to the opposed lateral ends of the support shaft 82 and a positioning cylindrical body 84 disposed between the pair of right and left cylindrical bodies 83, 83 and outwardly engaged with the support shaft 82.
[0053]
The support shaft 82 is formed of a metal bar having a circular vertical cross section. The pair of right and left cylindrical bodies 83, 83 and the positioning cylindrical body 84 respectively comprise a resin tube having a circular vertical cross section. [0054]
As shown in Fig. 5 and Fig. 6, the pair of right and left cylindrical bodies 83, 83 are disposed with an axis 83a of the cylindrical body 83 being downwardly offset relative to an axis 82a of the support shaft 82 such that an inner peripheral face of the cylindrical body 33 directly contacts the outer peripheral face of the support shaft 82 and the outer peripheral face of the support shaft 82 and the inner peripheral face of the cylindrical body 83 are in point contact with each other as seen in the direction along the axis of the support shaft 82.

[0055]
When one cylindrical body 83 tends to displace in its position along the support shaft 82, one end face 84a of the positioning cylindrical body 84 comes into abutment against one end face 83e of one cylindrical body 83, thus providing a stop function, and one main frame 11a provides a stopping action to the other end face 83e of the one cylindrical body 83. When the other cylindrical body 83 tends to displace in its position along the support shaft 82, the other end face 84a of the positioning cylindrical body 84 comes into abutment against one end face 83e of the other cylindrical body 83 and the other main frame 11a provides a stopping action to the other end face 83e of the other cylindrical body 83.

Therefore, the pair of right and left cylindrical bodies 83, 83 will be fixed in position at the receiving/stopping position to the forward side of the endless conveyer belts 12, 24 or 33, by the positioning cylindrical body 84, the main frame 11a or 21a or 32a.

[0056]
The pair of right and left cylindrical bodies 83, 83 of the supporting means 80 included in the first seedling box conveyer 10, the second seedling box conveyer 20 and the third seedling box conveyer 30 are fixed in position at the respective receiving position for the corresponding one of the pair of right and left endless conveyer belts 12, 12 or 24, 24 or 33, 33. As the left cylindrical body 83 is supported by the support shaft 82 as being rotated relative to this support shaft 82 by the rotational force applied thereto through its contact with the forward side of the left side endless conveyer belt 12 or 24 or 33, the left cylindrical body 83 supports and receives from under the forward side of the left endless conveyer belt 12 or 24 or 33 at the receiving portion 83b. As the right cylindrical body 83 is supported by the support shaft 82 as being rotated relative to this support shaft 82 by the rotational force applied thereto through its contact with the forward side of the right side endless conveyer belt 12 or 24 or 33, the right cylindrical body 83 supports and receives from under the forward side of the right endless conveyer belt 12 or 24 or 33 at the receiving portion 83b.

[0057]
Therefore, with the supporting means 80 included in the first seedling box
conveyer 10, the second seedling box conveyer 20 and the third seedling box conveyer 30, the pair of right and left cylindrical bodies 83, 83 are rotatably supported by the support shaft 82. The pair of right and left cylindrical bodies 83, 83 are rotated through contact with the endless conveyer belt 12 or 24 or 33, thus reducing the frictional force generated between the cylindrical bodies 83 and the endless conveyer belt 12 or 24 or 33. At the same time, the endless conveyer belt 12 or 24 or 33 is received and supported from under by the pair of right and left cylindrical bodies 83, thereby preventing sagging of the endless conveyer belt 12 or 24 or 33 due to the load of the seedling box 2. [0058]
The pair of right and left cylindrical bodies 83, 83 and the one positioning cylindrical body 84 of each supporting means 80 are formed of three separate pipes of an equal length obtained by dividing a single long pipe. With this, the specification of each cylindrical body 83 to be attached to the support shaft 82 so as to provide receiving and supporting action to the forward side of the endless conveyer belt 12 or 24 or 33 is rendered identical to the specification of the positioning cylindrical body 84 to be attached to the support shaft 82 for providing positioning action to the pair of right and left cylindrical bodies 83, 83.

[0059]
Fig. 7 is a side view in vertical section showing the condition wherein one cylindrical body 83 of the supporting means 80 is attached to the support shaft 82 in replacement or as a substitute for the positioning cylindrical body 84. As shown in this figure, if frictional wear has occurred at the portion 83b of the cylindrical body 83 receiving and supporting the conveyer 12 or 24 or 33, the worn cylindrical body 83 will be interchanged with the positioning cylindrical body 84 and attached as such on the support shaft 82 such that the worn cylindrical body 83 is disposed at the attaching position of the positioning cylindrical body 84 in replacement there for and the positioning cylindrical body 84 is disposed at the attaching position of the worn cylindrical body 83 in replacement therefor. With this, the positioning cylindrical body 84 will function as the receiving and supporting means in replacement for the worn cylindrical body 83, whereas the worn cylindrical body 83 will function as the positioning cylindrical body in replacement for the positioning cylindrical body to provide the position fixing function to the cylindrical bodies 83, 84, thus receiving and supporting the forward side of the pair of right and left endless conveyer belts 12,12 or 24, 24 or 33, 33.

[0060]
Next, the seedbed soil supplying device 40 will be described.

[0061]
Fig. 8 is a front view in vertical section showing the seedbed soil supplying device 40. Fig. 9 is a side view in vertical section showing the seedbed soil supplying device 40. As shown in these figures and in Fig. 1, the seedbed soil supplying device 40 includes the machine body 42 having a front wall plate 42a and a rear wall plate 42a connected in distribution to the pair of right and left main frames 21a, 21a of the second seedling box conveyer 20, the hopper type seedbed soil tank 43 having its lower portion formed continuously with the machine body 42, a feeding belt 44 disposed downwardly of the seedling box conveying path of the second seedling box conveyer 20 adjacent the lower side of a discharge opening 43c located at the bottom of the seedbed soil tank 43, a supplying chute 45 disposed adjacent the downstream side in the seedling box conveying direction of the discharge end of the feeding belt 44 and the leveling brush 41 provided on more downstream side in the seedling box conveying direction than the supplying chute 45.

[0062]
The seedbed soil tank 43 has a charge opening 43d formed at the upper end portion of this seedbed soil tank 43 and open upwardly. As an amount of chaff smoked charcoal is charged through the charge opening 43d, the charged chaff smoked charcoal is fed through the discharge opening 43c and received on the forward side 44a of the feeding belt 44 and stored under this condition within the tank. [0063]
The seedbed soil tank 43 includes a pair of stirring rotary bodies 46, 47 drivably and rotatably disposed in juxtaposition along the moving direction (Ö (see Fig. 8) of the feeding belt 44 in the vicinty of the upper portion of the discharge opening 43c inside the tank.

[0064]
The pair of stirring rotary bodies 46, 47 each includes a stirring drive shaft 46a or 47a rotatably supported to the front and rear wall plates 42a of the seedbed soil tank 43 and a plurality of stirring arms 48 attached to the stirring drive shaft 46a or 47a in juxtaposition in the axial and peripheral directions of this stirring drive shaft 46a or 47a. Each stirring arm 48 includes an arm body 48a extending from the stirring drive shaft 46a or 47a in the radial direction of the stirring rotary bodies 46 or 47 and a stirring pawl 48b extending from the leading end of the arm body 48a along the rotational axis direction of the stirring rotary bodies 46 or 47.

[0065]
Therefore, the pair of stirring rotary bodies 46, 47, as the stirring drive shaft 46a or 47a is rotatably driven, is driven to rotate in the rotational direction (r), thus effecting stirring of the chaff smoked charcoal present inside the seedbed soil tank 43 with the stirring arms 48, thereby preventing clogging of an amount of chaff smoked charcoal reserved in the seedbed soil tank 43 in the from of a bridge upwardly of the discharge opening 43c.

[0066]
The feeding belt 44 is wound around a driven wheel 90 disposed slightly upstream in the seedling box conveying direction relative to the discharge opening 43c of the seedbed soil tank 43 and rotatably supported to the wall plate 42a via a rotational support shaft 90a and a drive wheel 91 disposed slightly downstream in the seedling box conveying direction relative to the discharge opening 43c of the seedbed soil tank 43 and rotatably supported to the wall plate 42a. The drive wheel 91 is provided to be rotatable in unison with a feeding drive shaft 92 drivably and rotatably supported to the wall plate 42a.

[0067]
As the feeding drive shaft 92 is driven, the feeding belt 44 is rotatably driven by the drive wheel 91 with the forward side 44a thereof in opposition to the discharge opening 43c of the feeding belt 44 moves in the moving direction (£), whereby the chaff smoked charcoal reserved in the seedbed soil tank 43 is conveyed as being placed on the forward side 44a of the feeding face 44b provided along the entire length of the feeding belt 44 on the outer peripheral side of the feeding belt 44. Further, an amount of chaff smoked charcoal whose accumudation level has been rendered to a predetermined level under the shuttering action by a shutter 49 disposed on the downstream side in the seedling box conveying direction of the discharge opening 43c, is caused to drop from the discharge side of the feeding belt 44 into the supplying chute 45.
[0068]
Referring to the shutter 49, as a feeding adjusting lever 93 (see Fig. l) provided on the outer side of the machine body 42 is pivotally operated, the shutter 49 is slidably adjusted in the vertical direction, thus varying the accumulated material eutting-off position relative to the feeding belt 44, thereby to eventually change the feeding amount of the chaff smoked charcoal by the feeding belt 44.

[0069]
The feeding belt 44 includes anti-slip projections 44c formed on the feeding face 44b with a predetermined distance therebetween along the longitudinal direction of the feeding belt 44. These anti-slip projections 44c serve to prevent occurrence of suppage of the chaff smoked charcoal fed from the seedbed soil tank 43 by the feeding tank 44 relative to the feeding face 44b, thereby to prevent feeding failure of the chaff smoked charcoal by the feeding belt 44. Each anti-slip projection 44c has a shape that extends continuously along the whole width of the feeding face 44b and projects from the feeding face 44b linearly along the lateral width direction of the feeding face 44b, thus the projection extending normal to the moving direction (£) of the feeding belt 44.
[0070]
Referring to the supplying chute 45, connecting portions 45a provided at opposed ends of this supplying chute 45 are fastened and connected by connecting bolts to a bracket 42b fixed to the wall plate 42a. The supplying chute 45 receives an amount of chaff smoked charcoal from the feeding belt 44 without scattering of the charcoal to the seedling box conveying direction downstream side and causes the charcoal to gravity-fall. The chaff smoked charcoal coming into abutment against the supplying chute 45 is moved in the direction along and the direction normal to the seedling box conveying direction by the moving force applied thereto from the abutment against the supplying chute 45 Thus, the supplying chute 45 renders the thickness of the seedbed soil portion formed of the chaff smoked charcoal in the seedling box 2 as uniform as possible over the whole inside of the seedling box.

[0071]
The leveling brush 41 includes a leveling drive shaft 41a rotatably supported to an extension end portion of a support arm 94 extending downstream in the seedling box conveying direction from an end of the feeding drive shaft 42 on the outer face side of the front wall plate 42a and an extension end portion of a support arm 94 extending downstream in the seedling box conveying direction from the end of the feeding shaft 92 on the outer face side of the rear wall plate 42a and a plurality of column-like brushes 41b mounted to the leveling drive shaft 41a to be rotatable in unison therewith and in juxtaposition in the peripheral direction of this leveling drive shaft 41a.

[00721
The leveling brush 41 is rotatably driven in the rotational direction Z (see
Fig. 8) as the leveling drive shaft 41a is driven. With this, leading ends of the respective column-like brushes 41b are caused to enter the inside of the seedling box 2 which has passed under the supplying chute 45, whereby the seedbed soil portion inside the seedling box 2 is scraped off and leveled by the column-like brushes 41b. Each column-like brush 41b has a V-shape which extends more downstream in the rotational direction of the leveling brush 41 as extending to the inner side in the rotational axis direction of the levehng brush 41.

[0073]
Therefore, an amount of chaff smoked charcoal charged into the seedbed soil tank 43 is received by the feeding belt 44 and stirred by the pair of stirring rotary bodies 46, 47, thereby to prevent clogging of the chaff smoked charcoal and the charcoal is reserved in the seedbed soil tank 43 under this condition. And, as the feeding drive shaft 92 is driven, the feeding belt 44 is driven in the moving direction (i) by this feeding drive shaft 92 via the drive wheel 91. In the course of this, the chaff smoked charcoal reserved in the seedbed soil tank 43 is fed from the discharge opening 43a of the seedbed soil tank 43 by the forward side 44a of the feeding belt 44 and is caused to gravity-fall via the supplying chute 45, whereby a seedbed soil portion is formed by the amount of chaff smoked charcoal supplied and conveyed by the second seedling box conveyer 20. And, the seedbed soil portion formed in the seedling box 2 is leveled by the leveling brush 41.

[0074]
As shown in Fig. 8 and Fig. 9, the seedbed soil supplying device 40 includes a plate-like guide bodies 95 extending downward from the inner side of the front wall plate 42a and the rear wall plate 42a and extending also toward the conveyance path of the second seedling box conveyer 20. Each guide body 95 receives, with its guide face 95a, an amount of chaff smoked charcoal dropped off to the outer side in the direction normal to the seedling box conveying direction from the feeding belt 44 and the supplying chute 45 and an amount of chaff smoked charcoal splashed up off by the leveling brush 41 and guides them to drop to the inside of the seedling box 2, thus preventing inadvertent drop and accumulation of an amount of chaff smoked charcoal onto the upper face of the wall plate portion 2a (see Fig. 9) of the seedling box 2.
[0075]
As shown in Fig. 8, the seedbed soil supplying device 40 includes a scraper 96 provided on the outer side of the leveling brush 41. This scraper 96 is supported to a pair of support arms 94, 94 via connecting piece portions 96a

provided at opposed ends of the scraper 96, so that an amount of chaff smoked charcoal adhering to the leveling brush 41 is scraped off this leveling brush 41.
[0076]
The seedbed soil supplying device 40 includes a brush height adjusting mechanism 100 having an adjusting shaft 101 provided adjacent the outer side of the seedbed soil tank 43. By this brush height adjusting mechanism 100, the height adjustment of the leveling brush 41 is effected.

[0077]
As shown in Fig. 10 and Fig. 11, the brush height adjusting mechanism 100 includes, in addition to the adjusting shaft 101 described above, a pair of abutment blocks 102, 102 mounted in distribution to the opposed ends of the adjusting shaft 101, and a pair of stoppers 103, 103 providing receiving and stopping action to the pair of abutment blocks 102,102, respectively.

[0078]
The adjusting shaft 101 is disposed to extend rotatably through upper end portions of a pair of suspension arms 104,104 connected in distribution to a pair of support arms 94, 94 rotatably supporting the leveling brush 41.

[0079]
As shown in Fig. 10 and Fig. 12, each stopper 103 includes a vertically oriented threaded shaft portionl03a fitted in an attaching threaded hole 105a provided in a bracket 105 fixed to the front portion of the wall plate 42a and a block receiving portion 103b fixed to the upper end portion of this threaded shaft portionl03a.
[0080]
That is, with each stopper 103, in response to rotational adjustment of the block receiving portion 103b acting also as an operational portion, the threaded shaft portion 103a is rotated to be moved up/down relative to the bracket 105 and the block receiving portion 103b moves up/down together with the threaded shaft portion 103a, As a result, an upward adjustment is made such that the block receiving portion 103b positions the abutment block 102 at a position for receiving and supporting, higher than its position prior to the adjustment or a downward adjustment is made such that the block receiving portion103b positions the abutment block 102 at a position for receiving and supporting, lower than its position prior to the adjustment.

[0081]
As shown in Fig. 12, each abutment block 102 has a rectangular outer
peripheral shape and includes four abutment sides 102a-102d. With rotational adjustment of an operational tool 106 provided at one end of the adjusting shaft 102 to be rotatable therewith, the adjusting shaft 101 is rotated together with the operational tool 106 to rotate the pair of abutment blocks 102, 102, whereby one abutment side is selected from the four abutment sides 102a-102d of the pair of abutment blocks 102, 102 to be brought into abutment against the block receiving portion 103b of the stopper 103. As shown in Fig. 12, the distances of the four abutment sides 102a-102d of each abutment block 102 from the axis of the adjusting shaft 101 are set as four different kinds of distance. Hence, with each abutment block 102 in operation, with change of the abutment side brought into abutment against the block receiving portion 103b of the stopper 103, the disposing height of the adjusting shaft 101 received and supported via the abutment block 102 by the stopper 103 is varied.

[0082]
Therefore, with the brush height adjusting mechanism 100, through rotational adjustment of the operational tool 106, there is/are effected both or one of the adjustment of changing the abutment side of the abutment block 102 to be brought into abutment against the block receiving portion 103b of the stopper 103 and the adjustment of the attaching height of the stopper 103, through rotational adjustment of the block receiving portion 103b in each stopper 103. As a result, the disposing height of the adjusting shaft 102 is varied thereby to vertically pivot the pair of support arms 94, 94 about the rotational axis of the feeding drive shaft 92 and varying the attaching height of the leveling brush 41 relative to the machine body 42, so that the working position of the leveling brush 41 relative to the seedling box 2 is vertically varied. Each stopper 103 is fixed by a wing nut 108 at a predetermined attaching height relative to the bracket 105.

[0083]
The brush height adjusting mechanism 100 includes springs 107 connected to the opposed ends of the adjusting shaft 101. As these springs 107 urge the pair of abutment blocks 102, 102 against the block receiving portions 103b of the stoppers 103, floating displacement of the leveling brush 41 is prevented.
[0084]
Next, the irrigating device 50, the sowing device 60 and the cover soil supplying device 70 will be explained.

[0085]

As shown in Fig. 1 and Fig. 2, the irrigating device 50 includes a machine body 51 attached to the pair of right and left main frames 21a, 21a of the second seedling box conveyer 20 and an irrigating pipe 52 disposed at an upper portion in the seedling box conveying direction of the second seedling box conveyer 20 and connected to the machine body 51.

[0086]
In operation, the irrigating device 50 sprinkles or sprays irrigating water through discharge holes formed in juxtaposition in the irrigating pipe 52 along its axis onto the seedbed soil portion in the seedling box 2 from the seedbed soil supplying device 40 conveyed by the second seedling box conveyer 20.

[0087]
As shown in Fig. 1 and Fig. 2, the sowing device 60 includes a machine body 62 attached to the pair of right and left main frames 32a, 32a of the third seedling box conveyer 30, a seed tank 61 supported to this machine body 62 and a diffuser plate 63 provided downwardly of the discharge opening of the seed tank 61.

[0088]
The seed tank 61 includes a feeding roll 64 provided at the discharge opening of the seed tank 61 to be drivable and rotatable.

[0089]
With the sowing device 60 in operation, as the feeding roll 64 is driven, seeds reserved in the seed tank 61 are fed from the seed tank 61 by the feeding roll 64 to be dropped onto the diffuser plate 63 and the seeds from the diffuser plate 63 are caused to be dropped into the seedling box 2 conveyed by the third seedling box conveyer 30, whereby the seeds are supplied in scattering manner onto the seedbed soil portion after supply of irrigating water thereto by the irrigating device 50.

[0090]
As shown in Fig. 1 and Fig. 2, the cover soil supplying device 70 includes a machine body 72 attached to the pair of right and left main frames 32a, 32a of the third seedling box conveyer 30, a cover soil tank 71 supported to this machine body 72, and a diffuser plate 73 provided downwardly of the discharge opening of the cover soil tank 71.
[0091]
The cover soil tank 71 includes a feeding roll 74 provided at the discharge opening of the cover soil tank 71 to be drivable and rotatable and a stirring rotary body 75 provided drivably and rotatably adjacent an upper portion of the
discharge opening inside the cover soil tank 71.

[0092]
Therefore, with the cover soil supplying device 70 in operation, an amount of chaff smoked charcoal as an amount of cover soil charged into the cover soil tank 71 is stirred by the stirring rotary body 75, thereby preventing clogging of an amount of chaff smoked charcoal reserved in the cover soil tank 71 in the from of a bridge upwardly of the discharge opening and the chaff smoked charcoal is reserved under this condition in the cover soil tank 71. As the feeding roll 74 is driven, the chaff smoked charcoal reserved in the cover soil tank 71 is fed by the feeding roll 74 from the cover soil tank 71 to be dropped onto the diffuser plate 73 and the chaff smoked charcoal is dropped into the seedling box 2 from the sowing device 60 conveyed by the third seedling conveyer 30, whereby a cover soil portion of the chaff smoked charcoal is formed on the seedbed soil portion supplied with the seeds of the seedling box 2.

[0093]
In the sowing device 60 and the cover soil supplying device 70, when the seeds or chaff smoked charcoal dropped from the feeding roll 64 or 74 hits the diffuser plate 63 or 73, the seeds or chaff smoked charcoal will be dispersed by a moving force applied by this hitting in the seedling box conveying direction and in the direction normal to the seedling box conveying direction, With this, the diffuser plate 63, 73 of the sowing device 60 and the cover soil supplying device 70 uniformly disperses the seeds or the chaff smoked charcoal as cover soil over the entire surface of the seedbed soil portion in the seedling box 2.

[0094]
In the sowing device 60 and the cover soil supplying device 70, guide bodies having same guide faces as the guide bodies 95 included in the cover soil supplying device 40 are provided downwardly of opposed sides of the feeding roll 64 or 74 in the direction normal to the seedling box conveying direction, so that these guide bodies prevent inadvertent dropping and subsequent accumulation of the seeds or chaff smoked charcoal onto the upper end face of the wall plate 2a of the seedling box 2a.

[0095]
The seedbed soil tank 43 of the seedbed soil supplying device 40, the seed tank 61 of the sowing device 60 and the cover soil tank 71 of the cover soil supplying device 70 each includes a lower tank 43a or 61a or 71a connected to the

machine body 42 or 51 or 62 and an upper tank 43b or 61b or 71b detachably attached to the lower tank 43a or 61a or 71a. As the lower end portion of the upper tank 43b or 61b or 71b is pressed into the upper end portion of the lower tank 43a or 61a or 71a, communication and connection are established therebetween.
[0096]
That is, for conveyance of the seedling plant, the seedbed soil supplying device 40, the sowing device 60 and the cover soil supplying device 70 will be set into the compact condition with lower vertical height than the height under the used condition, with dismounting of the upper tank 43b or 61b or 71b. Further, between the lower side portions remaining as being connected to the conveyer apparatus C of the seedbed soil supplying device 40, the sowing device 60 and the cover soil supplying device 70, the upper tank 43b or 61b or 71b can be accommodated in a compact manner.
[0097]
Next, the construction for driving the conveyer apparatus C, the seeding soil supplying device 40, the sowing device 60 and the cover soil supplying device 70 will be described. [0098]
The seedling plant includes a motor 111 supported to an input case 110 provided at the end of the conveyance staring end of the conveyer frame 21 of the second seedling box conveyer 20, and a transmission mechanism 112 provided across and between a lateral side portion of the conveyer frame 21 of the second seedling box conveyer 20 and a lateral side portion of the conveyer frame 32 of the third seedling box conveyer 30. In operation, a drive force outputted from the motor 111 is transmitted by the transmission mechanism 112 to the second and third seedling box conveyers 20, 30 to drive the endless conveyer belts 12, 24, 33 of the first, second and third seedling box conveyers 10, 20, 30.
[0099]
The motor 111 is comprised of an electric powered motor. As shown in Fig. 1 and Fig. 2, the motor 111 is disposed on the more upstream side in the seedling box conveying direction than the seedbed soil supplying device 40 and between conveyance terminating ends of the seedbed soil supplying device 40 and the first seedling box conveyer 10.
Therefore, the motor 111 is located away from the irrigating device 50 and is also covered by the seedbed soil supplying device 40. As a result, wetting of the motor 111 with the irrigating water sprayed by the irrigating device 50 can be avoided. Further, as the motor 111 is located laterally of the first seedling box conveyer 10, thus being present nearby a worker who supplies the seedling box 2 to the first seedling box conveyer 10, the worker can readily carry out on/off operations of the motor 111.

[0100]
Fig. 14 is a diagram showing the construction of the transmission mechanism 112 in its front view. Fig. 15 is a plane view showing the transmission mechanism 112. Fig. 16 is a side view showing a portion where the motor 111 is disposed. As shown in these figures and also in Figs. 1 and 2, the transmission mechanism 112 includes the input case 110 extending upwardly from the main frame 21a of the second seedling box conveyer 20 and provided in this condition in the main frame 21a, a transmission case 113 extending between and across a lateral outer side of the main frame 21a of the second seedling box conveyer 20 and a lateral outer side of the main frame 32a of the third seedling box conveyer 30, an input chain 14 extending between inner sides in the transmission-wise upstream ends of the input case 110 and the transmission case 113, and a plurality of transmission chains 115 provided inside the transmission case 113 in juxtaposition along the transmitting direction.

[0101]
As shown in Figs. 14, 15 and 16, the input chain 114 is wound around an output sprocket 111b mounted on an output shaft 111a of the motor 111 to be rotatable therewith and an input sprocket 117 mounted on an input shaft 116 disposed on the inner side in the transmission-wise upstream end of the transmission case 113 to be rotatable therewith, thereby to operably couple the output shaft 111a of the motor 111 with the input shaft 116 of the transmission case 113. The input shaft 116 is mounted across and between the pair of right and left main frames 21a, 21a of the second seedling box conveyer 20, thus acting as a coupling shaft for operably coupling the pair of right and left main frames 21a, 21a.

[0102]
As shown in Fig. 14 and Fig. 15, one transmission chain 115 of the plurality of transmission chains 115 is wound around a transmission sprocket mounted on a relay transmission shaft 118 disposed adjacent the input shaft 116 of a plurality of relay transmission shafts provided inside the transmission case 113 in juxtaposition in the transmission direction to be rotatable therewith and a transmission sprocket 119 mounted on the input shaft 116 to be rotatable therewith. Some transmission chains 115 of the plurality of transmission chains 115 are wound around transmission sprockets mounted on a pair of adjacent relay transmission shafts 120,120 of the plurality of relay transmission shafts, thereby operably coupling the pair of adjacent relay transmission shafts 120, 120. Another transmission chain 115 of the plurality of transmission chains 115 is wound around a conveyer drive sprocket mounted on the drive shaft 26 of the second seedling box conveyer 20 to be rotatable therewith and an output sprocket mounted on a relay transmission shaft 121 disposed adjacent the drive shaft 26, thereby operably coupling the relay transmission shaft 121 with the drive shaft 26 of the second seedling box conveyer 20. One endless transmission chain 115 of the plurality of endless transmission chains 115 is wound around a drive sprocket mounted on the drive shaft 36 of the third seedling box conveyer 30 to be rotatable therewith and a transmission sprocket mounted on a relay transmission shaft 122 disposed adjacent the drive shaft 26, thereby operably coupling the relay transmission shaft 122 with the drive shaft 26 of the third seedling box conveyer 30.
[0103]
As shown in Fig. 2 and Fig. 15, the conveyance terminal side pulleys 15 around which the pair of right and left endless conveyer belts 12, 12 of the first seeding box conveyer 10 are wound and the starting end side pulleys 25 around which the conveyance starting side ends of the pair of right and left endless conveyer belts 24, 24 of the second seedling box conveyer 20 are wound are mounted on the starring side support shaft to be rotatable therewith. With this, the pair of right and left endless conveyer belts 12, 12 of the first seedling box conveyer 10 are driven with the power transmitted from the endless conveyer belt 24 of the second seedling box conveyer 20.
[0104J
The seedling plant includes a supply drive mechanism 130 configured to transmit the drive force of the motor 111 from the transmission mechanism 112 to the seedbed soil supplying device 40, thereby to drive the feeding belt 44, the stirring rotary bodies 46, 47 and the leveling brush 41.
[0105]
Fig. 17 is a front view showing the supply drive mechanism 130. As shown in this figure and also in Figs. 9, 14 and 15, the supply drive mechanism 130 includes a transmission chain 131 and a leveling transmission chain 132 that
are provided on the lateral outer side of the seedbed soil supplying device 40 on which the transmission mechanism 112 is disposed and a stirring transmission chain 133 and a coupling chain 134 that are disposed on the lateral outer side opposite to the side where the transmission mechanism 112 of the seedbed soil supplying device 40 is disposed. [0106]
The transmission chain 131 is wound around an output sprocket 135 mounted on a relay transmission shaft 124 to be rotatable therewith, the relay transmission shaft 124 being one of the plurality of relay transmission shafts which is located more upstream side in the seedling box conveying direction than the irrigating device 50 and more downstream side in the seedling box conveying direction than the motor 111, and an input sprocket 136 mounted on an end portion of the feeding drive shaft 92. The input sprocket 136 is operably coupled with the feeding drive shaft 92 via a clutch 145. [0107]
The leveling transmission chain 132 is wound around an output sprocket 137 mounted on an end of the feeding drive shaft 92 to be rotatable therewith and a leveling drive sprocket 138 mounted on an end of the leveling drive shaft 41a of the leveling brush 41 on the side where the transmission mechanism 112 is disposed.
[0108]
The stirring transmission chain 133 is wound around an output sprocket 139 mounted on the end of the feeding drive shaft 92 opposite to the end where the transmission mechanism 112 is located and a stirring drive sprocket 140 mounted on the end of the stirring drive shaft 46a of the stirring rotary body 46 of the pair of stirring rotary bodies 46, 47 closer to the feeding drive shaft 92 opposite to the side where the transmission mechanism 112 of the stirring drive shaft 46a is located. The coupling chain 134 is wound around an output sprocket 141 mounted at an end of the stirring drive shaft 46a of the stirring rotary body 46 of the pair of stirring rotary bodies 46, 47 to which the stirring transmission chain - 133 is connected and opposite to the end where transmission mechanism 112 is located and an input sprocket 143 mounted on an end of the stirring drive shaft 47a of the driven side stirring rotary body 47 of the pair of rotary bodies 46, 47 to which the stirring transmission chain 133 is not connected.
[0109]
Therefore, with the supply drive mechanism 130 in operation, the drive

force of the motor 111 transmitted to the transmission mechanism 122 is transmitted from the relay transmission shaft 124 via the transmission chain 131 to the feeding drive shaft 92, and from this feeding drive shaft 92 via the stirring transmission chain 133 to one stirring rotary body 46. Then, the force is transmitted from the stirring drive shaft 46 of this one stirring rotary body 46 to the other stirring rotary body 47 via the coupling chain 134 and from the feeding drive shaft 92 via the leveling transmission chain 132 to the leveling brush 141. Hence, as the motor 111 for driving the first, second and third seedling box conveyers 10, 20, 30 acts as the drive source, the feeding belt 44, the pair of stirring rotary bodies 46, 47, and the leveling brush 41 are driven. The supply drive mechanism 130 drives and rotates the pair of stirring rotary bodies 46, 47 so that these bodies are rotated in a same rotational direction (r). [0110]
As shown in Fig. 14 and Fig. 15, the sowing device 60 includes a sowing drive chain 66 that is wound around an output sprocket mounted on the relay transmission shaft 125 located downwardly of the sowing device 60 and of the plurality of relay transmission shafts of the transmission mechanism 112 to be rotatable therewith and an input sprocket mounted on a sowing drive shaft constituted of a rotational support shaft of the feeding roll 64. In operation, the drive force of the motor 111 transmitted to the transmission mechanism 122 is transmitted from the relay transmission shaft 125 via the sowing drive chain 66 to the feeding drive shaft 64, thereby to drive the feeding roll 64. [0111]
The cover soil supplying device 70 includes a cover soil drive chain 77 wound around an output sprocket mounted on one relay transmission shaft 122 of the plurality of the relay transmission shafts of the transmission mechanism 112 to be rotatable therewith, the shaft 122 being located downwardly of the cover coil supplying device 70, and an input sprocket mounted on a cover soil drive shaft 76 constituted of a rotational support shaft of the feeding roll 74 to be rotatable therewith and a stirring transmission chain 79 wound around a transmission sprocket mounted on a cover soil drive shaft 76 to be rotatable therewith and an input sprocket mounted on a stirring drive shaft 78 constituted of a rotational support shaft of the stirring rotary body 75 to be rotatable therewith.
[0112]
Therefore, with the cover soil supplying device 70 in operation, the drive force of the motor 111 transmitted to the transmission mechanism 122 is transmitted from the relay transmission shaft 122 via the cover soil transmission chain 77 to the cover soil transmission shaft 76 and from this cover coil transmission shaft 76 via the stirring drive chain 79 to the stirring drive shaft 78, thereby to drive the feeding roll 74 and the stirring rotary body 75.
[0113]
In these ways, the conveyer apparatus C, the seedbed soil supplying device 40, the sowing device 60 and the cover soil supplying device 70 are driven by the single motor 111.
[0114]
As shown in Fig. 9, the clutch 145 is provided between the feeding drive shaft 92 of the seedbed soil supplying device 40 and the input sprocket 136. This clutch 145 is switched over by a clutch lever 146 (see Pig. l) disposed on the lateral outer side of the seedbed soil supplying device 40 between an engaged state and a disengaged state, thus switching over the force transmission to the feeding drive shaft 92 between engaged state and disengaged state, whereby the feeding belt 44, the stirring rotary bodies 46, 47 and the leveling brush 41 are driven or stopped.
[0115]
As shown in Fig. 13, each support arm 94 supporting the leveling brush 41 includes a shaft support member 149 connected to the leading end of the support arm 94 by a connecting bolt 148, so that the arm 94 supports, via this shaft support member 149, the levelig drive shaft 41a of the leveling brush 41.
[0116]
With variable adjustment of the attaching position of the shaft support member 149 relative to the support arm 94 along the extending direction of the support arm 94 with the function of the elongate slot-like bolt hole 149a provided in the shaft support member 149, the leveling drive shaft 41a of the leveling brush 41 is moved along the shaft hole 94a formed as a cutout hole of the support arm 94, whereby the leveling drive sprocket 138 is moved together with the leveling drive shaft 41a.
[0117]
That is, with varying the attaching position of the shaft support member 149, the attaching position of the leveling drive sprocket 138 is varied, thereby to adjust the tension of the leveling transmission chain 132.
[0118]
As shown in Fig. 9, the machine frame 42 of the seedbed soil supplying device 40 is operably connected to the second seedling box conveyer 20 via
connection changing mechanisms 150 provided at the opposed ends of the lower end of the front wall plate 42a and the lower end of the rear wall plate 42a in the seedling box conveying direction.
[0119]
As shown in Fig. 18, each connecting changing mechanism 150 includes a machine body side connecting plate portion 151 provided as a belt portion extending to the lateral outer side of the conveyer at the lower end of the wall plate 42a of the seedbed soil supplying device 40 and a connecting bolt 152 fitted through and between this connecting plate portion 151 and the main frame 21a of the conveyer frame 21 of the second seedling box conveyer 20.
[0120]
With each connection changing mechanism 150 in operation, as a bolt hole 153 provided in the connection plate portion 151 is provided as a guide hole having a rectangular hole shape, with moving adjustment of the machine body 42 of the seedbed soil supplying device 40 along the main frame 21a, the connecting position of the machine body 42 relative to the conveyer frame 21a of the second seedling box conveyer 20 can be varied in the seedling box conveying direction.
[0121]
As shown in Fig. 9 and Fig. 17, the output sprocket 135 as an upstream side wheel body around which the transmission-wise upstream portion of the transmission chain 131 for transmission from the relay transmission shaft 124 of the transmission mechanism 112 to the feeding drive shaft 92 is supported to the conveyer frame side to be rotatable about the axis extending normal to the seedling box conveying direction. And, the input sprocket 136 as a downstream side wheel body around which the transmission-wise downstream portion of the transmission chain 131 is wound is supported to the machine body side of the seedbed soil supplying device 40 to be rotatable about the axis extending normal to the seedling box conveying direction.
[0122]
Therefore, by varying the connecting position of the machine body 42 of the seedbed soil supplying device 40 relative to the conveyer frame 21 of the second seedling box conveyer 20 with the function of each connection changing mechanism 150, the seedbed soil supplying device 40 as a whole is moved in the seedling box conveying direction, whereby the input sprocket around which the transmission-wise downstream portion of the transmission chain 131 is wound is moved relative to the output sprocket 135 around which the transmission-wise upstream portion of the transmission chain 131 is wound, in the direction normal to the rotational axis of each sprocket 135, 136, thus enabling tension adjustment of the transmission chain 131.
[0123]
As shown in Fig. 3 and Fig. 16, the motor 111 is supported to a motor mount 159 including an input case 110 and a motor mount body 159a having one end thereof connected to an inner wall plate 110a of the input case 110. The motor mount 159 is connected to the conveyer frame 21 of the second seedling box conveyer 20 via motor mount connection changing mechanisms 155 provided at the opposed ends of the inner wall plate 110a of the input case 110 in the seedling box conveying direction and motor mount connection changing mechanisms 155 provided at the opposed ends of the motor mount body 159a at the end opposite to the input case 110 side in the seedling box conveying direction.
[0124]
As shown in Fig. 19, each motor mount connection changing mechanism 155 includes a motor mount side connecting plate portion 156 provided as a bent portion provided at the lower end of the inner wall plate 110a or the motor mount body 159a extending to the lateral outer side, and a connecting bolt 157 fitted between and through this connecting plate portion 156 and the main frame 21a of the second seedling box conveyer 20.
[0125]
With each motor mount connection changing mechanism 155 in operation, as a bolt hole 158 provided in the motor side connection plate portion 156 is provided as a guide hole having a rectangular hole shape, with moving adjustment of the motor mount 159 along the main frame 21a, the connecting position of the motor mount 159 relative to the conveyer frame 21 of the second seedling box conveyer 20 can be varied in the seedling box conveying direction.
[0126]
As shown in Fig. 17, the output sprocket 111b around which the transmission-wise upstream portion of the input chain 114 for transmission from the output shaft 111a of the motor 111 to the input shaft 116 of the transmission case 113 is supported to the motor mount 159 side to be rotatable about the axis extending normal to the seedling box conveying direction. And, the input sprocket 117 around which the transmission-wise downstream portion of the input chain 114 is wound is supported to the conveyer frame 21 side of the second seedling box conveyer 20 to be rotatable about the axis extending normal to the seedling box conveying direction.
[0127]
Therefore, by changing the connecting position of the motor mount 159 relative to the main frame 21 with the function of each motor mount connection changing mechanism 155, the motor 111 is moved together with the motor mount 159 in the seedling box conveying direction and the output sprocket 111b around which the transmission-wise upstream side of the input chain 114 is wound is moved in the direction normal to the axis of the rotational axis of each sprocket, relative to the input sprocket 117 around which the transmission-wise downstream side of the input chain 111 is wound, thus enabling tension adjustment of the input chain 114.
[0128]
[Alternative Embodiments]
Fig. 20 is a side view in vertical section showing supporting means 80 according to a first alternative embodiment. As shown in this figure, the supporting means 80 provided in the first alternative embodiment includes a metal support shaft 82 fixed to the pair of right and left main frames 11a, 11a or 21a, 21a or 32a, 32a of the conveyer frame 11 or 21 or 32 and a single cylindrical body 83 formed of resin and rotatably and outwardly engaged on this support shaft 82.
[0129]
The cylindrical body 83 includes a pair of receiving portions 83b, 83b and ,as being clamped between the pair of right and left main frames 11a, 11a, or 21a, 21a or 32a, 32a, is fixed in position at its receiving position for receiving and supporting the pair of right and left endless conveyer belts 12, 12 or 24, 24 or 33, 33, thus receiving and supporting, at one receiving portion 83b, from under the forward side of one of the pair of right and left endless conveyer belts 12,12 or 24, 24 or 33, 33 and receiving and supporting, at the other receiving portion 83b, from under the forward side of the other of the pair of right and left endless conveyer belts 12, 12 or 24, 24 or 33, 33.
[0130]
Fig. 21 is a side view in vertical section showing supporting means 80 according to a second alternative embodiment. As shown in this figure, the supporting means 80 provided in the second alternative embodiment includes a metal support shaft 82 fixed to the pair of right and left main frames 11a, 11a or 21a, 21a or 32a, 32a of the conveyer frame 11 or 21 or 32, and a pair of cylindrical bodies 83, 83 formed of resin and rotatably and outwardly engaged on the support shaft 82 in distribution to the opposed ends of this support shaft 82.
[0131]
The left side and right side cylindrical bodies 83 are clamped respectively between a positioning plate 85 outwardly fitted on the support shaft 82 and one main frame 11a or 21a or 32a, thus being fixed in position at the receiving position for receiving and supporting the left side or right side endless conveyer belt 12 or 24 or 33, and receives and supports, at a receiving portion 83b, from under the forward side of the left side or right side endless conveyer belt 12 or 24 or 33. The positioning plate 85 is received and supported by a stopper pin 86 fixedly attached to the support shaft 82. [0132]
Fig. 22 is a side view in vertical section showing supporting means 80 according to a third alternative embodiment. As shown in this figure, the supporting means 80 provided in the third alternative embodiment includes a metal support shaft 82 fixed to the pair of right and left main frames 11a, 11a or 21a, 21a or 32a, 32a of the conveyer frame 11 or 21 or 32, a pair of right and left cylindrical bodies 83, 83 formed of resin and rotatably and outwardly engaged on the support shaft 82 in distribution to the opposed ends of this support shaft 82, and a positioning cylindrical body 84 formed of resin and rotatably and outwardly engaged on the support shaft 82 between the pair of right and left cylindrical bodies 83, 83.
[0133]
The left side cylindrical body 83, as being clamped between one end face 84a of the positioning cylindrical body 84 and the left side main frame 11a or 21a or 32a, is fixed in position at its receiving position for receiving the left side endless conveyer belt 12 or 24 or 33, thus receiving and supporting from under, at the receiving portion 83b, the forward side of the left side endless conveyer belt 12 or 24 or 33.
[0134]
The right side cylindrical body 83, as being clamped between the other end face 84a of the positioning cylindrical body 84 and the right side main frame 11a or 21a or 32a, is fixed in position at its receiving position for receiving the right side endless conveyer belt 12 or 24 or 33, thus receiving and supporting from under, at the receiving portion 83b, the forward side of the right side endless conveyer belt
12 or 24 or 33.
[0135]
In the case of the supporting means 80 provided in the second alternative embodiment and the supporting means 80 provided in the third alternative embodiment, the receiving portion 83b of the left side and right side cylindrical bodies 83 for receiving the forward side of the endless conveyer belt 12 or 24 or 33 is set with an offset to one end side of the cylindrical body 83 relative to a center portion 83c thereof in the axial direction of the cylindrical body 83.
[0136]
Therefore, with the supporting means 80 provided in the second alternative embodiment and the third alternative embodiment, even when frictional wear has occurred in the receiving portion 83b of the cylindrical body 83 for receiving the endless conveyer belt 12 or 24 or 33, by changing the attaching orientation of this worn cylindrical body 83, this worn cylindrical body 83 can be reused.
[0137]
That is, if frictional wear has occurred at the portion 83b ("receiving portion 83b" hereinafter) of the cylindrical body 83 for receiving the endless conveyer belt 12 or 24 or 33, the attaching orientation will be changed such that one end of the cylindrical body 83 which was located on the left side of the endless conveyer belt 12 or 24 or 33 prior to the occurrence of the frictional wear is moved to the right side of the endless conveyer belt 12 or 24 or 33. With this, the worn-out receiving portion 83b is removed from the forward side of the endless conveyer' belt 12 or 24 or 33, whereas the portion thereof which was away from the forward side of the endless conveyer belt 12 or 24 or 33 and was unused is now brought into opposition to the forward side of the endless conveyer belt 12 or 24 or 33 and acts as a new portion for receiving this forward side of the endless conveyer belt 12 or 24 or 33.
[0138]
[Other Embodiments]
(l) In the foregoing embodiment, the pair of right and left cylindrical bodies 83, 83 and the positioning cylindrical body 84 are all provided with the same length, so as to allow the positioning cylindrical body 84 to be used in replacement for the left/right cylindrical body 83. Instead of this, the right and left cylindrical bodies 83, 83 may have a different length than the positioning cylindrical body 84 so that the positioning cylindrical body 84 may be used as and in replacement for the cylindrical body 83. As long as the positioning cylindrical body 84 can be used in replacement for the cylindrical body 83 to support the endless conveyer belt, the substantially same function/effect as that of the foregoing embodiment can be achieved, Therefore, the length of the right and left cylindrical bodies 83, 83 may be different from the length of the positioning cylindrical body 84. In this case, the lengths of the pair of right and left cylindrical bodies 83, 83 may be different from each other.
(2) Instead of the mode of embodiment wherein two endless conveyer belts are juxtaposed in the direction normal to the seedling box conveying direction, the invention may be embodied also with three or more endless conveyer belts being juxtaposed in the direction normal to the seedling box conveying direction. In this case too, the object of the present invention can be achieved.

[0139]
The present invention is applicable not only to the seeding box conveyer to be installed in a seedling plant, but also to a seedling box conveyer to be installed in a warehouse, a vehicle, an agricultural field, for loading/unloading a seedling box, etc.

[Description of Reference Marks and Numerals]

[0140]
2 seeding box
11, 21, 32 conveyer frame
12, 24, 33 endless conveyer
13, 22, 34 conveyance starting side support shaft 26, 36 conveyance terminating side support shaft 80 supporting means
82 support shaft
82a axis of the support shaft
83 cylindrical body
83b receiving portion for receiving and supporting an endless conveyer belt
83c center portion of the cylindrical body

83e end face of the cylindrical body 83a axis of the cylindrical body 84 positioning cylindrical body

Claims

1. A seedling box conveyer comprises:

a conveyer frame (11, 21, 32);

a plurality of endless conveyer belts (12, 24, 33) drivably and rotatably supported to the conveyer frame (11, 21, 32) and juxtaposed with a predetermined distance therebetween in a direction normal to a seedling box conveying direction;

a starting end support shaft (13, 22, 34) around which conveyance starting ends of the plurality of endless conveyer belts (12,24, 33) are wound; and

a terminating end support shaft (26, 36) around which conveyance terminating ends of the plurality of endless conveyer belts are wound,

the seedling box conveyer being configured to receive from under and convey a seedling box (2) by the endless conveyer belts (12, 24, 33);

wherein the seedling box conveyer comprises a supporting means (80) for receiving and supporting from under the forward sides of the plurality of endless conveyer belts (12, 24, 33) between the starting end support shaft (13, 22, 34) and the terminating end support shaft (26, 36); and

said supporting means (80) includes a support shaft (82) fixed to the conveyer frame (11, 21, 32) in the direction normal to the seedling box conveying direction and a cylindrical body (83) rotatably outwardly engaged and rotatably supported on the support shaft (82) and receiving the endless conveyer belts (12, 24, 33) , the cylindrical body (83) being outwardly engaged on the support shaft (82) with inner peripheral face of the cylindrical body (83) being in direct contact with an outer peripheral face of the support shaft (82).

2. A seedling box conveyer comprising

a conveyer frame (11, 21, 32);

a plurality of endless conveyer belts (12, 24, 33) drivably and rotatably supported to the conveyer frame (11, 21, 32) and juxtaposed with a predetermined distance therebetween in a direction normal to a seedling box conveying direction;

a starting end support shaft (13, 22, 34) around which conveyance starting ends of the plurality of endless conveyer belts (12, 24, 33) are wound; and
a terminating end support shaft (26, 36) around which conveyance terminating ends of the plurality of endless conveyer belts (12, 24, 33) are wound, the seedling box conveyer being configured to receive from under and convey a seedling box (2) by the endless conveyer belts (12, 24, 33);

wherein the seedling box conveyer comprises a supporting means (80) for receiving and supporting from under the forward sides of the plurality of endless conveyer belts (12, 24, 33) between the starting end support shaft (13, 22, 34) and the terminating end support shaft (26, 36); and

said supporting means (80) includes a support shaft (82) fixed to the conveyer frame (11, 21, 32) in the direction normal to the seedling box conveying direction and a plurality of cylindrical bodies (83) rotatably outwardly engaged and rotatably supported on the support shaft (82) and receiving the endless conveyer belts (12, 24, 33) respectively, the cylindrical bodies (83) being outwardly engaged on the support shaft (82), with inner peripheral faces of the cylindrical bodies (83) being in direct contact with an outer peripheral face of the support shaft (82).

3. The seedling box conveyer according to claim 2, wherein a portion
of the cylindrical body (83) receiving the forward side of the endless belt (12, 24,
33) is offset to one side toward one terminating end of the cylindrical body (83)
relative to the axial center of the cylindrical body (83).

4. The seedling box conveyer according to claim 2 or 3, wherein:

there is provided a positioning cylindrical body (84) disposed between a
pair of cylindrical bodies (83) for respectively receiving a pair of endless conveyer belts (12, 24, 33) of the plurality of endless conveyer belts (12, 24, 33), said positioning cylindrical body (84) contacting end faces of said pair of cylindrical bodies (83) so as to fix these paired cylindrical bodies (83) in position for receiving the endless conveyer belts (12, 24, 33), and

said paired cylindrical bodies (83) and said positioning cylindrical body (84) have identical specifications such that said paired cylindrical bodies (83) may be attached to said support shaft (82) as positioning means as a substitute for said positioning cylindrical body (84) and said positioning cylindrical body (84) may be attached to said support shaft (82) as receiving means as a substitute for said paired cylindrical bodies (83).

5. The seedling box conveyer according to any one of claims 1-4,
wherein the axis of the cylindrical body (83) is offset relative to the axis of the
support shaft (82), with an outer peripheral face of the support shaft (82) being in
point-contact with an inner peripheral face of the cylindrical body (83) as seen in
the direction along the axis of the support shaft (82).