1. A hood locking device (3) for a work vehicle having a hood (21), the hood (21) having a transversal pivot (xl) on a side thereof adjacent a vehicle body and being engageable/disengageable with/from the vehicle body on a side thereof remote from the pivot, characterized by an engaged element (30) provided on one of the hood (21) and the vehicle body; a fixing bracket (4) provided on the other of the hood (21) and the vehicle body; an engagement retaining element (5) which is provided on said the other and engageable with the engaged element (30); and a biasing spring (31) which is provided on said the other and configured to exert a bias force on the engagement retaining element (5) to an engagement retaining posture side; wherein the fixing bracket (4) has an engagement recess (40) which is engageable/disengageable with/from the engaged element (30) in a vertical direction from said one of the hood (21) and the vehicle body, and which limits a movement of the engaged element (30) in a horizontal direction which crosses an engagement-disengagement direction; the engagement retaining element (5) includes a retaining projection (51), the retaining projection (51) preventing the engaged element (30), having engaged with the engagement recess (40), from coming off in the vertical direction when the engagement retaining element (5) is in the engagement retaining posture; and the retaining projection (51) is retracted from the engagement recess (40) to allow the engaged element (30) to come off of the engagement recess (40) when the engagement retaining element (5) is shifted to an engagement retention canceling posture, against the biasing force of the biasing spring (31); and the engagement retaining element (5) further includes a canceling position retaining portion (54) which is configured to engage the engaged element (30) when the engagement retaining element (5) is in the engagement retention canceling posture, wherein the canceling position retaining portion (54) is configured to prevent the engagement retaining element (5) from returning to the engagement retaining posture, against the biasing force of the biasing spring (31), under a weight of the hood which is applied as a load to a position of contact between the engaged element (30) and the canceling position retaining portion (54).

2. The hood locking device according to claim 1, wherein a position of contact between the engagement recess (40) and the engaged element (30) is at a same height level as the position of contact between the canceling position retaining portion (54) and the engaged element (30) when the engagement retaining element (5) is in the engagement retention canceling posture.

HOOD LOCKING DEVICE FOR WORK VEHICLE

FIELD OF THE INVENTION

The present invention relates to a hood locking device for a work vehicle having a hood, the hood having a transversal pivot on a side thereof adjacent a vehicle body and being engageable/ disengageable with/from the vehicle body on a side thereof remote from the pivot.

DESCRIPTION OF THE RELATED ART

A known hood locking device for a work vehicle, with its hood engageable/disengageable with/from the vehicle body on a swing end side (on a side remote from the pivot) as described above, includes the devices (1) and (2) as under:-

(1) One device including: a fixing bracket mounted on a vehicle body; an engagement retaining element which is provided on the vehicle body and engageable with an engaged element on the hood side; a biasing spring for biasing the engagement retaining element to an engagement retaining posture side; an operation tool for operating the engagement retaining element to a coming-off prevention canceling side; and an elastic element for slightly lifting the hood upon canceling the coming-off prevention (see JP 8-026140 A).

(2) Another device including: a fixing bracket mounted on the hood side; an engagement retaining element which is provided on the hood side and engageable with an engaged element provided on the vehicle body side; a biasing spring for biasing the engagement retaining element to the engagement retaining posture side; an operation tool for operating the engagement retaining element to the coming-off prevention canceling side; and an operation element and an elastic element for slightly lifting the hood upon canceling the coming-off prevention (see JP 6-035557 U1).

In the above-mentioned conventional hood locking devices, the means for slightly lifting the hood along with the coming-off prevention canceling operation is provided. Accordingly, these devices are useful in that, for a lifting operation with a hand, the hood is conveniently lifted slightly so that the hand can be put in a space below the hood.

In case of the work vehicle, however, the hood may not necessarily be opened unless a gap is provided between the hood and the vehicle body by slightly lifting up the hood. Instead, the hood may be opened by utilizing a recess or a projection formed in the hood or the vehicle body.

In this case, there would be an advantage of further simplifying the structure, if the means for slightly lifting up the hood is omitted. However, in the structure each of the known devices as exemplified above, if the means for slightly lifting up the hood is omitted, then the position of the engaged element provided on the hood side does not change even after an operation of canceling the hood engagement is performed. As a result, when the engagement canceling operation is quit, the hood engagement state is resumed again.

Accordingly, if the means described above is omitted, the hood lifting operation should be performed under the condition that the engagement canceling operation is continuously performed.

Therefore, one object of the invention is to provide a hood locking device for a work vehicle with enhanced operability, in which the means for slightly lifting up the hood upon canceling the coming-off prevention by the engagement retaining element is omitted, while a cancellation state of the engagement retaining element can be retained even after the coming-off prevention canceling operation is quit.

SUMMARY OF THE INVENTION

The above object is fulfilled according to one aspect of the present invention as under:-,
A hood locking device for a work vehicle having a hood, the hood having a transversal pivot on a side thereof adjacent a vehicle body and being engageable/disengageable with/from the vehicle body on a side thereof remote from the pivot, characterized by an engaged element provided on one of the hood and the vehicle body;

a fixing bracket provided on the other of the hood and the vehicle body;

an engagement retaining element which is provided on said the other and engageable with the engaged element; and

a biasing spring which is provided on said the other and configured to exert a bias force on the engagement retaining element to an engagement retaining posture side; wherein
the fixing bracket has an engagement recess which is engageable/disengageable with/from the engaged element in a vertical direction from said one of the hood and the vehicle body, and which limits a movement of the engaged element in a horizontal direction which crosses an engagement-disengagement direction; the engagement retaining element includes a retaining projection, the retaining projection preventing the engaged element, having engaged with the engagement recess, from coming off in the vertical direction when the engagement retaining element is in the engagement retaining posture; and the retaining projection is retracted from the engagement recess to allow the engaged element to come off of the engagement recess when the engagement retaining element is shifted to an engagement retention canceling posture, against the biasing force of the biasing spring; and the engagement retaining element further includes a canceling position retaining portion which is configured to engage the engaged element when the engagement retaining element is in the engagement retention canceling posture, wherein the canceling position retaining portion is configured to prevent the engagement retaining element from returning to the engagement retaining posture, against the biasing force of the biasing spring, under a weight of the hood which is applied as a load to a position of contact between the engaged element and the canceling position retaining portion.
According to the configuration described above, the engagement retaining element includes the canceling position retaining portion which is configured to

engage the engaged element upon shifting to the engagement retention canceling posture. In the canceling position retaining portion, the weight of the hood loaded on the contacting part between the engaged element and the canceling position retaining portion prevents a movement of the engagement retaining element biased to the engagement retaining posture side by the biasing force of the biasing spring.

Accordingly, in a state in which the weight of the hood acts on the contacting part between the engaged element and the canceling position retaining portion, the engagement retaining element does not return to the engagement retaining posture side, even when the coming-off prevention canceling operation on the engagement retaining element is quit.

In addition, when the weight of the hood on the canceling position retaining portion is removed, the engagement retaining element returns to the engagement retaining posture side, by an action of the biasing spring for biasing the engagement retaining element to the engagement retaining posture side.

Therefore, by omitting the means for slightly lifting up the hood upon canceling the coming-off prevention by the engagement retaining element, the structure of the hood locking device can be simplified. In addition, when the hood is lifted up, it becomes unnecessary to perform, for example, the operation of lifting up the hood and the coming-off prevention canceling operation on the engagement retaining element at the same time. By simply performing the coming-off prevention canceling operation on the engagement retaining element, a coming-off prevention canceling state of the engagement retaining element is retained even when the coming-off prevention canceling operation is quit, and thus there is an advantage that both hands can be used for lifting up the hood.

According to one preferred embodiment, a position of contact between the engagement recess and the engaged element is at a same height level as the position of contact between the canceling position retaining portion and the engaged element when the engagement retaining element is in the engagement retention canceling posture. This configuration is further advantageous in the following manner.

As described above, since the position where the engagement recess is brought into contact with the engaged element and the position where the canceling position retaining portion of the engagement retaining element in the engagement retention canceling posture is brought into contact with the engaged element are at the same height level, when the coming-off prevention canceling operation on the engagement retaining element is performed, it is not necessary to perform an operation that changes a vertical positional relationship between the engagement recess and the engaged element to a large degree from a state in which the engaged element is present in the engagement recess. It is suffice that the engagement retaining element is simply shifted from the engagement retaining posture in which the engaged element is present in the engaging recess to the engagement retention canceling posture in which the engaged element is positioned in the canceling position retaining portion.

In this case, since the position where the engagement recess is brought into contact with the engaged element and the position where the canceling position retaining portion of the engagement retaining element in the engagement retention canceling posture is brought into contact with the engaged element are at the same height level, a vertical displacement of the engaged element during the shift from the engagement retaining posture side to the canceling position retaining portion can be suppressed to be small. Therefore, there is an advantage that the coming-off prevention canceling operation is not likely to be influenced by the weight of the hood and can be performed relatively lightly, even without using the means for biasing the hood in the lifting direction.

Other features and advantages will become apparent by reading the description as follows with reference to the accompanying drawings.

In the following description, unless otherwise stated, a direction in which the vehicle body advances straight forward is referred to as "front/rear direction", a horizontal direction orthogonal to the front/rear direction is referred to as "right/left direction (or transverse direction)", and a direction perpendicular to both the front/rear direction and the right/left direction is referred to as "vertical direction". Unless otherwise stated, the terms related to the transversal direction, i.e., "right" and "left" mean those seen from a driver seated on the driver's seat.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is an overall side view of a tractor having a hood locking device.

Fig. 2 is an overall side view of a hood part of the tractor shown in Fig. 1.

Fig. 3 is a front view of the hood part.

Fig. 4 is a plan view of the hood locking device according to a first embodiment.

Fig. 5 is a front view of the hood locking device.

Fig. 6 shows the hood locking device alone, in which: (a) is a perspective view of the hood locking device as seen from the front and the left; and (b) is a perspective view of the hood locking device as seen from the rear and the left.

Fig. 7 is an exploded perspective view of the hood locking device.

Fig. 8 explains actions of the hood locking device, in which: (a) shows an engagement retaining posture of an engagement retaining element; (b) shows an engagement retention canceling posture of the engagement retaining element; and (c) shows the engagement retaining element when the hood is opened.

Fig. 9 explains actions of the hood locking device according to a second embodiment, in which: (a) shows the engagement retaining posture of the engagement retaining element; (b) shows the engagement retention canceling posture of the engagement retaining element; and (c) shows the engagement retaining element when the hood is opened.
Fig. 10 is a perspective view of the hood locking device according to a third embodiment as seen from the front and the right.

Fig. 11 is a side view showing the hood locking device according to the third embodiment, in which: (a) is a left side view of the hood locking device shown in Fig. 10; and (b) is a left side view of the hood locking device shown in Fig. 10, with a part of the structure being modified.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of the present invention will be described hereinafter in detail with reference to the accompanying drawings. [First Embodiment] [Overall configuration of the tractor]

Fig. 1 shows a tractor to which a hood locking device for work vehicle according to the present invention is applied.

In the tractor, a self-propelled vehicle body 1 including an engine mount frame 10, an intermediate transmission case 11 and a rear transmission case 12 is supported by a pair of right/left steerable front wheels 13 on an engine mount frame 10 side, and by rear wheels 14 on a rear transmission case 12 side.

In a front part of the vehicle body 1, a motor section 2 is provided, and rearward of the motor section 2, a control part 16 having a steering wheel 15, and a driver's seat 17 are arranged. A work implement, such as a rotary tilling device (not shown), can be connected to a rear part of the vehicle body 1 through a lift arm 18 and a link mechanism 19, in such a manner that a lifting and lowering operation of the work implement can be performed.

[Motor section]

The motor section 2 includes a hood 21 so as to cover an engine 20 as well as ancillary equipments of the engine, such as a cooling radiator, an air cleaner and a battery (not shown), all of which are mounted on the engine mount frame 10. In a front part of the engine mount frame 10, a lower cover 10A is provided for covering a lower portion of a front part of the hood 21.

The hood 21 is pivoted at a rear end thereof to a rear frame 22 which stands on a connecting part between the hood 21 and the control part 16, to be vertically swingable about a transversal shaft xl (corresponding to a pivot). The hood 21 includes: a top panel part 21a; a front grill 21b provided on a front part of the top panel part 21a; and lateral walls 21c provided on right/left sides of the top panel part 21a. On an upper part of the front grill 21b, lights for illuminating forward are provided. The front grill 21b is supported on a top panel part 21a side by a band plate-shaped stay 21A extending downward from a lower face of a front end part of the top panel part 21a.

As shown in Figs. 2 and 3, in an inner space of the hood 21, a gate-shaped fixing frame 23 for attaching the various ancillary equipments stands from the lower cover 10A of the engine mount frame 10, and in a left upper part of the fixing frame 23 (right side in Fig. 3), a stopper fitting 24 is attached.

The stopper fitting 24 allows engagement/disengagement with/from a lower end side of a support stay 25 which prevents the hood 21 from returning to a close state of the hood 21 when the hood 21 is swung upward into an open state about the transversal shaft xl extending on the rear end side of the hood 21. The stopper fitting 24 is a plate-like member bent in a crank shape whose upper end part has a locking hole 24a formed therein.

On the other hand, the support stay 25 is a rod-like member whose upper end part is bent in the transverse direction, and is mounted on an upper side in the hood 21 by being inserted into a pivot hole 26a formed in a mount piece 26. A transversally bent part inserted into the pivot hole 26a serves as a transversal shaft x2 oriented in the right/left direction, and the support stay 25 is attached swingably in a front/rear direction about the transversal shaft x2. The lower end side of the support stay 25 is bent in a shape of a hook and configured so as to be engaged with and disengaged from the locking hole 24a.
It should be noted that at the mount part for the support stay 25 in the hood 21, a fitting part between the transversally bent part serving as the transversal shaft x2 and the pivot hole 26a into which the transversally bent part is inserted is formed to have some room to realize a somewhat loose fitting, so that a position of the lower end can be somewhat changed in the right/left direction.

[Hood locking device]

On a side of the vehicle body opposite to a side of the transversal shaft xl as the pivot of the hood 21, that is, in a front end side of the vehicle body 1, a hood locking device 3 is provided.

As shown in Figs. 3-7, the hood locking device 3 includes: a fixing bracket 4 attached to the lower cover 10A on the engine mount frame 10 side forming the vehicle body 1; a round rod-shaped engaged element 30 provided on the hood 21; an engagement retaining element 5 engageable with the engaged element 30; and a biasing spring 31 for biasing the engagement retaining element 5 to an engagement retaining posture side.

The engaged element 30 is connected to a supporting member 2IB for supporting a lower end part of the front grill 21b, which supporting member 2IB is connected to a lower part of the band plate-shaped stay 21A extending downward from the top panel part 21a.
The fixing bracket 4 has an engagement recess 40 formed in an intermediate part thereof in the right/left direction, with which recess 40 the engaged element 30 on the hood 21 side is engageable from above, and from which recess 40 the engaged element 30 is disengageable. On each lateral side of the engagement recess 40, an inclined face 41 is formed which slopes upward from the engagement recess 40 so that the engaged element 30 on the hood 21 side is surely guided into the engagement recess 40.

On one lateral end side (right side in Fig. 5) of the fixing bracket 4, a cutout 42 is formed for limiting a moving range of a stopper pin 53 coming into contact therewith, which pin 53 is provided on the engagement retaining element 5 and will be described later in more detail. The cutout 42 is configured in such a manner that an engagement retaining posture and the engagement retention canceling posture of the engagement retaining element 5 can be determined in position by an upper edge 42u and a lower edge 42d of the cutout 42.

In other words, with reference to Fig. 5, in the engagement retaining posture, the stopper pin 53 provided on the engagement retaining element 5 is brought into contact with the upper edge 42u of the cutout 42 as indicated with a solid line. On the other hand, in the engagement retention canceling posture, the stopper pin 53 provided on the engagement retaining element 5 is brought into contact with the lower edge 42d of the cutout 42 as indicated with an imaginary line.

The engagement retaining element 5 is pivoted to the fixing bracket 4 so as to be swung about a pivot shaft 50, and is switchable between the engagement retaining posture and the engagement retention canceling posture as described above.

The engagement retaining element 5 has a retaining projection 51 configured to limit from above an upward disengagement of the engaged element 30 which is engaged with the engagement recess 40 of the fixing bracket 4, when the engagement retaining element 5 is in the engagement retaining posture. On an upper side of the retaining projection 51, an inclined face 52 is formed for providing a component force for rotating the engagement retaining element 5 per se toward an engagement retention canceling posture side, by coming into contact with the engaged element 30 moving downward toward the engagement recess 40 to enter the recess 40 from above. The stopper pin 53 as described above is unified with the engagement retaining element 5, and positioned in an area defined by the cutout 42 of the fixing bracket 4.

The engagement retaining element 5 also has a canceling position retaining portion 54 for receiving the engaged element 30 is engaged when the engagement retaining element 5 is shifted to the engagement retention canceling posture.

The canceling position retaining portion 54 is configured to retain the engagement retention canceling posture of the engagement retaining element 5 and prevent the engagement retaining element 5 from returning to the engagement retaining posture side, against a bias force to the engagement retaining posture side by the biasing spring 31, under a weight of the hood 21 which is applied as a load through the engaged element 30 to the canceling position retaining portion 54.

In other words, in the engagement retention canceling posture as shown with the imaginary line in Fig. 5, a bottom part 54b of the canceling position retaining portion 54 (corresponding to a position of contact between the canceling position retaining portion 54 and the engaged element 30 when the engagement retaining element 5 is in the engagement retention canceling posture) is at a same height level as that of a bottom part 40a of the engagement recess 40 (corresponding to a position of contact between the engagement recess 40 and the engaged element 30). When the weight of the hood 21 acts on the bottom part 54b, in cooperation with a movement limiting part 54a on a lateral side the bottom part 54b (right side in Fig. 5), the bottom part 54b can retain the engagement retaining element 5 in the engagement retention canceling posture, against the biasing force to the engagement retaining posture side by the biasing spring 31.
The biasing spring 31 has hook parts on both end sides, with one end side being engaged with a fixing fitting 10a provided on the lower cover 10A, and the other end side being engaged with an engaging elongate hole 55 formed in the engagement retaining element 5.

A longitudinal direction of the engaging elongate hole 55 is aligned with an extending direction of the biasing spring 31 when the engagement retaining element 5 is in the engagement retaining posture, so that the hook part of the biasing spring 31 can be easily engaged with the engaging elongate hole 55 under a smaller biasing force of the biasing spring 31.

An imaginary line LI interconnecting opposite ends of the biasing spring 31 and extending in an acting direction of the biasing force lies exclusively above an imaginary line L0 interconnecting one end of the biasing spring 31 which is engaged with the fixing fitting 10a on the lower cover 10A and an axis of a pivot shaft 50 acting as a swing center of the engagement retaining element 5. Since the imaginary line LI does not extend below the imaginary line L0 beyond the axis of the pivot shaft 50, the biasing force of the biasing spring 31 consistently acts on the engagement retaining element 5 toward the engagement retaining posture side about the pivot shaft 50.

In an upper end part of the engagement retaining element 5, a connecting hole 56 for connecting a manual operation tool 32 is provided. In the lower cover 10A, an elongate hole 10B oriented in the right/left direction is formed. The operation tool 32 connected to the connecting hole 56 is disposed through the elongated hole 10B and spans between an inside and outside of the lower cover 10A, in a posture inclined obliquely downward and leftward when seen from the front, with an operation part 32a of the operation tool 32 being positioned below the lower cover 10A.

Accordingly, through a push-pull operation of the operation tool 32 connected to the connecting hole 56, the operation part 32a of the operation tool 32 from a lateral side of the front part of the vehicle body 1 is operated, whereby the engagement retaining element 5 can be switched over between the engagement retaining posture and the engagement retention canceling posture with a simple operation.

Fig. 8 shows a locking operation and a lock releasing operation of the hood 21 using the hood locking device 3 of the present invention.

Specifically, in Fig. 8 (a), the engaged element 30 on the hood 21 side is put into the engagement recess 40 of the fixing bracket 4, and the retaining projection 51 of the engagement retaining element 5 is positioned above the engaged element 30. This state is retained by a pulling action of the biasing spring 31. In other words, Fig. 8 (a) shows a state in which the engagement retaining posture is retained.

Fig. 8 (b) shows a state in which the manual operation tool 32 is pulled against the biasing force of the biasing spring 31, and the engagement retaining element 5 is switched to the engagement retention canceling posture.

In this state, while the biasing force of the biasing spring 31 returning to the engagement retaining posture side acts on the engagement retaining element 5, the engaged element 30 on the hood 21 side is positioned in the canceling position retaining portion 54 and the hood weight acts on the canceling position retaining portion 54. In this state, in order for the engaged element 30 to go beyond the movement limiting part 54a, it is necessary to apply a force that can overcome a resistance by the hood weight and move the engagement retaining element 5. Since such a force should be larger than the return-biasing force by the biasing spring 31, the engagement retaining element 5 is retained in the engagement retention canceling posture even after the manual operation of the operation tool 32 is released.

When the hood 21 as shown in Fig. 8 (b) is lifted upward, the engagement retaining element 5 rotates to the engagement retaining posture side under the return-biasing force of the biasing spring 31, and returns to the state as shown in Fig. 8 (c).

When the engaged element 30 as shown in Fig. 8 (c) is moved downward, the engaged element 30 is brought into contact with the inclined face 52 of the engagement retaining element 5, and the weight of the hood 21 rotates the engagement retaining element 5 about the pivot shaft 50 against the biasing force of the biasing spring 31. The engaged element 30 enters the engagement recess 40 of the fixing bracket 4, into the engagement retaining posture as shown in Fig. 8 (a).

[Second embodiment]

The structure of the hood locking device 3 is not limited to those in the embodiment described above, and may be, for example, those in the following embodiment. Hereinafter, the same components as those in the foregoing embodiment are designated with the same reference characters and thus duplicate description is omitted.

In the structure of a second embodiment shown in Fig. 9, the fixing bracket 4 has a similar configuration to those in the embodiment described above. The engagement retaining element 5 is transversally slidably attached to the fixing bracket 4 and biased to the engagement retaining posture side by the biasing spring 31.

In a slide structure of the engagement retaining element 5, a pair of guide pins 43, 43 formed in the fixing bracket 4 enter respective elongate holes 57, 57 formed in the engagement retaining element 5 to be freely slidable.

A length in a slide direction of each of the elongate holes 57, 57 is set in a manner as follows. As shown in Fig. 9 (a), each guide pin 43 may be brought into contact with an end part of the corresponding elongate hole 57 when the engagement retaining element 5 is in the engagement retaining posture in which the biasing spring 31 exerts the pulling action in one direction. As shown in Fig. 9(b), on the other hand, the engagement retaining element 5 may be shifted to the engagement retention canceling posture and each guide pin 43 may be brought into contact with the other end part of the corresponding elongate hole 57 when the manual operation tool 32 is pulled against the biasing force of the biasing spring 31.

In the state shown in Fig. 9 (b), while the biasing force of the biasing spring 31 returning to the engagement retaining posture side acts on the engagement retaining element 5, the engaged element 30 on the hood 21 side is positioned in the canceling position retaining portion 54 and the hood weight acts on the canceling position retaining portion 54. In this state, in order for the engaged element 30 to go beyond the movement limiting part 54a, it is necessary to apply a force that can overcome a resistance by the hood weight and move the engagement retaining element 5. Since such a force should be larger than the return-biasing force by the biasing spring 31, even after the manual operation of the operation tool 32 is released, the engagement retaining element 5 is retained in the engagement retention canceling posture, like in the foregoing embodiment.

In addition, when the hood 21 as shown in Fig. 9 (b) is lifted upward, the engagement retaining element 5 is shifted to the engagement retaining posture side under the return-biasing force of the biasing spring 31, and returns to the state as shown in Fig. 9 (c), like in the foregoing embodiment also.

In this embodiment, the engagement retaining element 5 is attached to the fixing bracket 4 in such a manner that a rear face of the engagement retaining element 5 is brought into slide contact with a front face of the fixing bracket 4, an end part of the biasing spring 31 is engaged with a frontward bent piece 5a provided on one lateral end side of the engagement retaining element 5, and the manual operation tool 32 is engaged with a frontward bent piece 5b provided on the other end side of the engagement retaining element 5.

[Third embodiment]

Further, the structure of the hood locking device 3 is not limited to those in the embodiments described above, and may be, for example, those as shown in Figs. 10 and 11.
In this structure, in addition to the fixing bracket 4 and the engagement retaining element 5, there is provided a guide rail 6 for slidably guiding the engagement retaining element 5 relative to the fixing bracket 4 in a transverse direction.

As shown in Figs. 10 and 11 (a), the guide rail 6 includes a hollow-ground (U-groove) shaped rail part 60 elongated in the transversal direction; and an erecting piece 61 standing upward in an intermediate part of the rail part 60. A base part 5 A formed on a lower end side of the engagement retaining element 5 is fitted into a groove 60A of the transversally elongated rail part 60, to be slidable in a longitudinal direction of the U-groove.

A guide pin 62 is fixed to the erecting piece 61. The guide pin 62 extends through a horizontally elongated elongate hole 57 formed in the engagement retaining
element 5, so that a slidable range of the engagement retaining element 5 is defined
and limited by contact between the guide pin 62 and respective opposite ends of the
elongate hole 57.

With this structure, an open/close operation of the hood 21 can be performed with a similar action to that shown in Figs. 9(a) - 9(c).

In other words, like the state as shown in Fig. 9(a), in the state shown in Fig. 10, the engaged element 30 on the hood 21 side enters the engagement recess 40 of the fixing bracket 4, and the retaining projection 51 of the engagement retaining element 5 is positioned above the engaged element 30, and this state is retained by the pulling action of the biasing spring 31.

When the manual operation tool 32 in this state is pulled against the biasing force of the biasing spring 31, like the state as shown in Fig. 9(b), the engagement retaining element 5 is shifted to the engagement retention canceling posture so that the engaged element 30 on the hood 21 side is positioned in the canceling position retaining portion 54.

When the hood 21 in this state is lifted upward, like the state as shown in Fig. 9(c), the engagement retaining element 5 returns to the engagement retaining posture side by the return-biasing force of the biasing spring 31.

Compared with the structure as shown in Figs. 10 and 11(a), the structure as shown in Fig. 11(b) is different only in a shape associated with the rail part 60 of the guide rail 6, and the remaining features are identical to those in the former structure.

In the present structure, the rail part 60 is configured to have a float prevention piece 64 on an open side of the groove 60A. With this configuration, the base part 5 A of the lower end side of the engagement retaining element 5 is prevented from being afloat.

Finally, the reference numeral 63 each in Figs. 11(a) and 11(b) denotes a backup strip for sandwiching the engagement retaining element 5 between the erecting piece 61 and the backup strip 63 so that the engagement retaining element 5 may be movable relative to the erecting piece 61 and the backup strip 63.

[Other embodiments]

(1) In the above-described embodiments, the bottom part 54b of the canceling position retaining portion 54 when the engagement retaining element 5 is in the engagement retention canceling posture (corresponding to a position of contact between the canceling position retaining portion 54 and the engaged element 30 when the engagement retaining element 5 is in the engagement retention canceling posture) is set at a same height level as that of the bottom part 40a of the engagement recess 40 (corresponding to a position of contact between the engagement recess 40 and the engaged element 30). Alternatively, for example, the bottom part 54b of the canceling position retaining portion 54 is made a slightly higher than the bottom part 40a of the engagement recess 40 when the engagement retaining element 5 is in the engagement retention canceling posture, so that the weight of the hood 21 aggressively acts on the engagement retaining element 5.

(2) In the above-described embodiments, the hood 21 is provided with the
engaged element 30, while the lower cover 10A of the vehicle body 1 is provided with
the fixing bracket 4, the engagement retaining element 5 engageable with the engaged
element 30, and the biasing spring 31 for consistently biasing the engagement
retaining element 5 to the engagement retaining posture side, but the present invention
is not limited to this configuration.

Conversely, the lower cover 10A or other part of the vehicle body 1 may be provided with the engaged element 30, while the hood 21 may be provided with the fixing bracket 4, the engagement retaining element 5 engageable with the engaged element 30, and the biasing spring 31 for consistently biasing the engagement retaining element 5 to the engagement retaining posture side.

(3) The hood locking device described above is applicable to various work
vehicles such as a combine, a mower, a rice transplanter and construction machinery,
in addition to the tractor described in the embodiments.

WE CLAIM:

1. A hood locking device (3) for a work vehicle having a hood (21), the hood (21) having a transversal pivot (xl) on a side thereof adjacent a vehicle body and being engageable/disengageable with/from the vehicle body on a side thereof remote from the pivot,

characterized by

an engaged element (30) provided on one of the hood (21) and the vehicle body;

a fixing bracket (4) provided on the other of the hood (21) and the vehicle body;

an engagement retaining element (5) which is provided on said the other and engageable with the engaged element (30); and

a biasing spring (31) which is provided on said the other and configured to exert a bias force on the engagement retaining element (5) to an engagement retaining posture side; wherein

the fixing bracket (4) has an engagement recess (40) which is engageable/disengageable with/from the engaged element (30) in a vertical direction from said one of the hood (21) and the vehicle body, and which limits a movement of the engaged element (30) in a horizontal direction which crosses an engagement-disengagement direction; the engagement retaining element (5) includes a retaining projection (51), the retaining projection (51) preventing the engaged element (30), having engaged with the engagement recess (40), from coming off in the vertical direction when the engagement retaining element (5) is in the engagement retaining posture; and the retaining projection (51) is retracted from the engagement recess (40) to allow the engaged element (30) to come off of the engagement recess (40) when the engagement retaining element (5) is shifted to an engagement retention canceling posture, against the biasing force of the biasing spring (31); and

the engagement retaining element (5) further includes a canceling position retaining portion (54) which is configured to engage the engaged element (30) when the engagement retaining element (5) is in the engagement retention canceling posture, wherein the canceling position retaining portion (54) is configured to prevent the engagement retaining element (5) from returning to the engagement retaining posture, against the biasing force of the biasing spring (31), under a weight of the hood which is applied as a load to a position of contact between the engaged element (30) and the canceling position retaining portion (54).

2. The hood locking device according to claim 1, wherein

a position of contact between the engagement recess (40) and the engaged element (30) is at a same height level as the position of contact between the canceling position retaining portion (54) and the engaged element (30) when the engagement retaining element (5) is in the engagement retention canceling posture.