JP4511289B2 - Working vehicle - Google Patents

Description

  The present invention relates to a work vehicle such as a passenger rice transplanter, and more particularly to a work vehicle that automatically turns and turns a side clutch inside a turn in response to a turning operation of a steering handle.

2. Description of the Related Art A working vehicle is known that automatically disengages a side clutch inside a turn in response to a turning operation of a steering handle (see Patent Document 1). This type of work vehicle includes a front-wheel steering mechanism that steers the left and right front wheels according to the operation of the steering handle, and left and right side clutches that are built into the rear axle case, and the operation of each side clutch. The arm is connected to the front wheel steering mechanism via a steering interlock mechanism.
JP 2003-81127 A

  However, in the thing of patent document 1, since a steering interlocking mechanism is comprised with a pair of right and left connecting rods, and the connecting rods directly connect the operating arms of the side clutches to the front wheel steering mechanism, the side clutch Therefore, there is a possibility that the operability of the steering wheel may be reduced because the operation load directly acts on the steering wheel. In such a configuration, since there is no degree of freedom in the arrangement of the connecting rod, depending on the model, the inner end of the steered front wheel interferes with the connecting rod, or the connecting rod is attached to the member arranged at the bottom of the fuselage. There was a possibility of problems such as interference.

The present invention has been created in view of the above-described circumstances in order to solve these problems, and the invention of claim 1 steers the left and right front wheels in accordance with the operation of the steering handle. The steering wheel includes a front wheel steering mechanism and left and right side clutches mounted in the rear axle case, and the operation arm of each side clutch is connected to the front wheel steering mechanism via a steering interlock mechanism. In a working vehicle that automatically disengages the side clutch inside the turn in response to a turning operation, a steering load reducing action unit including a link mechanism is provided in an intermediate portion of the steering interlock mechanism, and the steering Upon Ru biases the body outwardly with respect to the first half portion of the rear half portion of the interlocking mechanism, downward from the rear accelerator case The bottom end of the shifter shaft that protrudes is provided with a base end portion of the operation arm that extends outward in the left-right direction of the airframe, while the steering load reducing action portion is downward from the airframe bottom at the rear position of the front wheel. A connecting arm facing in the left-right direction that rotates back and forth around a support shaft that extends toward the center is used. The inner end of the connecting body is connected to the steering handle, and the outer end of the connecting body is connected to the operating arm. A working vehicle characterized by being configured to be coupled . If comprised in this way, not only the operation load of a steering wheel can be reduced, but the latter half part of a steering interlocking mechanism can be biased to the outer side of a body, and interference with the member arrange | positioned at the body bottom part can be avoided. In other words, the front half of the steering interlock mechanism can be biased to the inside of the machine body with respect to the rear half, so that interference with the front wheels can be avoided.
The invention of claim 2 is characterized in that the rotation center of the link mechanism is arranged on the outer side of the machine body with respect to the rotation center of the operation arm. If comprised in this way, since the arm ratio of a link mechanism can be enlarged, the operation load of a steering handle can further be reduced.
According to a third aspect of the present invention, an interlock release mechanism for releasing the steering interlock of the side clutch is provided at an intermediate portion of the steering interlock mechanism, and the interlock release mechanism is disposed on the inner side of the body from the inner end of the front wheel turning locus. It is characterized by that. If comprised in this way, it will become possible not only to cancel | release the steering | linkage interlocking | linkage of a side clutch, but to avoid interference with an interlock | release cancellation | release mechanism and a front wheel.

  Next, embodiments of the present invention will be described with reference to the drawings. In the drawing, 1 is a traveling machine body of a riding rice transplanter, and a planting part 3 is connected to a rear portion of the traveling machine body 1 via an elevating link mechanism 2, and the traveling machine body 1 itself includes at least The engine 4 mounted on the front of the aircraft, the transmission case 5 for shifting the power of the engine 4, the front wheels 7 provided on the left and right sides of the transmission case 5 via the front axle case 6, and the left and right sides of the rear axle case 8 A rear wheel 9 is provided.

  The power shifted in the transmission case 5 is transmitted to the left and right front wheels 7 via the front axle case 6, and is transmitted to the left and right rear wheels 9 via the rear axle case 8. Is also transmitted. Inside the rear axle case 8, left and right rear wheel power transmission paths for branching the power input from the mission case 5 and transmitting to the left and right rear wheels 9 are formed. Side clutches 10 are respectively provided in the left and right rear wheel power transmission paths, and power transmission to the left and right rear wheels 9 is individually interrupted based on the on / off operation.

  The side clutch 10 of the present embodiment is a wet multi-plate clutch, and includes an inner cylinder member 12 that is spline-fitted to the upstream transmission shaft 11, a retaining ring 13 and a plurality of disks 14 that are provided on the outer periphery of the inner cylinder member 12. The outer cylinder member 16 integrally coupled to the downstream transmission shaft 15, the retaining ring 17 and the plurality of disks 18 provided on the inner periphery of the outer cylinder member 16, and between the inner cylinder member 12 and the outer cylinder member 16. And a spring 19 that biases the inner cylinder member 12 in the separating direction, a shifter shaft 20 that extends downward from one end position of the inner cylinder member 12 and projects out of the case, and a lower body of the shifter shaft 20. An operation arm 21 extending in the outward direction is provided.

  The disks 14 and 18 are alternately polymerized between the retaining rings 13 and 17 and are always compressed by the urging force of the spring 19. Thereby, the inner cylinder member 12 and the outer cylinder member 16 are integrally rotated by the frictional force between the disks 14 and 18, and the rotation of the upstream transmission shaft 11 is transmitted to the downstream transmission shaft 15. On the other hand, when the operation arm 21 is pulled forward, the shifter shaft 20 pushes the inner cylinder member 12 against the spring 19. As a result, slip occurs between the disks 14 and 18, and power transmission from the upstream transmission shaft 11 to the downstream transmission shaft 15 is cut off.

  The left and right front wheels 7 are provided in the front axle case 6 so as to be steerable, and are steered according to the operation of the steering handle 22. The front wheel steering mechanism 23 that steers the front wheel 7 includes a steering shaft 24 that rotates according to the operation of the steering handle 22, a pitman arm 25 that is provided integrally with the steering shaft 24, and the pitman arm 25 that moves the left and right front wheels. 7 and a pair of left and right rods 26 that are connected to each other.

  In the present invention, the operation arm 21 of each side clutch 10 is connected to the front wheel steering mechanism 23 via a pair of left and right steering interlocking mechanisms 27, so that the side on the inner side of the turn can be controlled according to the turning operation of the steering handle 22. The clutch 10 is automatically disengaged. The steering interlock mechanism 27 includes a front half 27a whose front end is connected to the front wheel steering mechanism 23, a rear half 27b whose rear end is connected to the operation arm 21, and a steering that connects the front half 27a and the rear half 27b. And a load reducing action portion 27c.

  An interlocking plate 28 extending in the left-right direction is integrally provided at the lower end portion of the steering shaft 24, and arc-shaped elongated holes 28 a centering on the steering shaft 24 are formed at both left and right end portions thereof. Has been. The front half 27a of the steering interlocking mechanism 27 is composed of a first connecting rod 29 that faces in the front-rear direction, and a pin 29a that is loosely fitted in the long hole 28a of the interlocking plate 28 is provided at the front end thereof. That is, when the steering handle 22 is turned left, the left first connecting rod 29 is pushed backward, and when the steering handle 22 is turned right, the right first connecting rod 29 is pushed backward.

  The rear half part 27b of the steering interlocking mechanism 27 is composed of a second connecting rod 30 that faces in the front-rear direction, and the rear end part thereof is connected to the operation arm 21 of the side clutch 10 via a pin 30a.

  The steering load reducing action part 27c is composed of a link mechanism, and is composed of, for example, a connecting arm 31 facing in the left-right direction. The connecting arm 31 is configured to rotate back and forth around a support shaft 31a extending downward from the bottom of the machine body, and is connected to the rear end portion of the first connection rod 29 inside the machine body of the support shaft 31a. And connected to the front end portion of the second connecting rod 30 outside the body of the support shaft 31a.

  That is, when the left first connecting rod 29 is pushed backward in response to the left turning operation of the steering handle 22, the left connecting arm 31 rotates and pulls the left second connecting rod 30 forward. The operating arm 21 of the left side clutch 10 is pulled, and the power transmission to the left rear wheel 9 is cut off. Further, when the right first connecting rod 29 is pushed rearward in response to the right turning operation of the steering handle 22, the right connecting arm 31 rotates and pulls the right second connecting rod 30 forward. As a result, the operating arm 21 of the right side clutch 10 is pulled, and the power transmission to the right rear wheel 9 is cut off. At this time, the first arm length (the length from the rotation center to the first connection rod connection point) in the connection arm 31 is greater than the second arm length (the length from the rotation center to the second connection rod connection point). By increasing the length, it is possible to reduce the steering operation load.

  According to the configuration as described above, the steering load reducing action portion 27c formed of a link mechanism is interposed in the intermediate portion of the steering interlock mechanism 27, and the latter half portion 27b of the steering interlock mechanism 27 is made to the front half portion 27a. Since it can be biased to the outside, not only can the operating load on the steering handle 22 be reduced, but it is also possible to avoid the rear half portion 27b of the steering interlocking mechanism 27 from interfering with members disposed at the bottom of the body. In other words, the front half portion 27a of the steering interlock mechanism 27 can be biased toward the inside of the machine body with respect to the rear half portion 27b, so that interference with the front wheels 7 can also be avoided.

  In the present embodiment, the operation arm 21 of the side clutch 10 is rotated in the range outside the machine body with respect to the arm rotation center, and the rotation center of the connecting arm 31 is outside the machine body from the rotation center of the operation arm 21. Is arranged. In this way, the arm ratio (first arm length / second arm length) of the connecting arm 31 can be increased, and the operation load on the steering handle 22 can be further reduced. Further, in the present embodiment, the rotation fulcrum of the connection arm 31 is arranged behind the front wheel rotation locus in a side view, so that the interference between the connection arm 31 and the front wheel 7 can be reliably avoided.

  Next, the interlock release mechanism 32 that cancels the steering interlock of the side clutch 10 will be described. The interlock release mechanism 32 is operated when the side clutch 10 is disengaged due to the steering interlock, and when the vehicle cannot travel due to insufficient driving force, and is configured to cancel the steering interlock of the side clutch 10 according to this operation. ing. Specifically, the pedal 33 that is depressed when the interlock is released, the side-reverse L-shaped release arm 34 that responds to the depression of the release pedal 33, and the left and right that are pulled forward by the release arm 34 when the release pedal is depressed. The rear end portion of the left release rod 35 is connected to the inner end portion of the left connecting arm 31, and the rear end portion of the right release rod 35 is connected to the right connecting arm 31. It is connected to the inner end of the.

  That is, when the release pedal 33 is stepped on in response to the turning operation of the steering handle 22 while either the left or right connecting arm 31 is rotated, the releasing rod 35 is pulled forward via the releasing arm 34, and the connecting arm 31 is returned to the clutch engagement side. Thereby, the steering interlock of the side clutch 10 can be temporarily released. In addition, between the release arm 34 and the release rod 35, an interchange means is provided that allows the release rod 35 to move when the steering is interlocked. Between the connection arm 31 and the first connection rod 29, the interlock is released. It is assumed that interchangeable means for allowing the movement of the connecting arm 31 is provided.

  Further, in the present embodiment, when the interlock release mechanism 32 is provided at the intermediate portion of the steering interlock mechanism 27, the interlock release mechanism 32 is disposed on the inner side of the body relative to the inner end of the front wheel rotation locus. Interference between the front wheel 32 and the front wheel 7 can also be avoided.

  The traveling machine body 1 of the present embodiment configured as described above includes a front wheel steering mechanism 23 that steers the left and right front wheels 7 in accordance with the operation of the steering handle 22, and left and right side clutches built in the rear axle case 8. 10 and the operation arm 21 of each side clutch 10 is linked to the front wheel steering mechanism 23 via the steering interlocking mechanism 27, so that the side clutch 10 on the inner side of the turn according to the turning operation of the steering handle 22. Is automatically turned off, but a steering load reducing action portion 27c made of a link mechanism is provided in the middle portion of the steering interlock mechanism 27 so that the rear half portion 27b of the steering interlock mechanism 27 is changed to the front half portion 27a. On the other hand, because it is biased to the outside of the aircraft, not only can the operation load on the steering wheel 22 be reduced, The second half portion 27b of the tearing interlocking mechanism 27 biases the body outside, it is possible to avoid interference with the member disposed in the fuselage bottom. In other words, the front half portion 27a of the steering interlock mechanism 27 can be biased toward the inside of the machine body with respect to the rear half portion 27b, so that interference with the front wheels 7 can also be avoided.

  In addition, since the arm rotation center of the steering load reduction action portion 27c is arranged outside the machine body with respect to the rotation center of the operation arm 21, the arm ratio of the steering load reduction action portion 27c is increased to operate the steering handle 22. The load can be further reduced.

  In addition, since an interlock release mechanism 32 for releasing the steering interlock of the side clutch 10 is provided in the middle part of the steering interlock mechanism 27, and the interlock release mechanism 32 is arranged on the inner side of the inner side of the front wheel turning locus, Not only can the steering interlock of the side clutch 10 be released as necessary, but also interference between the interlock release mechanism 32 and the front wheels 7 can be avoided.

It is a whole side view of a riding rice transplanter. It is a whole side view of the riding rice transplanter which shows a steering interlocking mechanism. It is a principal part side view of the riding rice transplanter which shows a steering interlocking mechanism. It is a whole top view of the riding rice transplanter which shows a steering interlocking mechanism. It is a principal part top view of the riding rice transplanter which shows a steering interlocking mechanism. It is the whole rear view of the riding rice transplanter which shows a steering interlocking mechanism. It is a principal part rear view of the riding rice transplanter which shows a steering interlocking mechanism. It is principal part sectional drawing which shows a side clutch.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Traveling machine body 7 Front wheel 8 Rear axle case 9 Rear wheel 10 Side clutch 21 Operation arm 22 Steering handle 23 Front wheel steering mechanism 27 Steering interlock mechanism 27a Front half part 27b Rear half part 27c Steering load reduction action part 29 First connection rod 30 Second connection Rod 31 Connecting arm 32 Interlocking release mechanism 33 Release pedal

Claims (3)

A front wheel steering mechanism that steers the left and right front wheels according to the operation of the steering handle, and left and right side clutches built in the rear axle case, and the operation arms of each side clutch are connected via a steering interlock mechanism. In a working vehicle that automatically engages and turns the side clutch inside the turn according to the turning operation of the steering handle by being linked to the front wheel steering mechanism, a link mechanism is provided at the intermediate portion of the steering interlock mechanism. and interposed the steering load mitigation action unit consisting, when Ru is biased on the body outwardly with respect to the first half portion of the rear half portion of the steering linkage mechanism, the lower end of the shifter shaft protruding downward from the rear accelerator case While providing a base end portion of the operation arm extending outward in the left-right direction of the fuselage, The load reducing action part uses a connecting arm facing in the left-right direction that pivots back and forth around a support shaft extending downward from the bottom of the machine body at the rear position of the front wheel. Is connected to the steering handle side, and the vehicle body outer end is connected to the operation arm side .   The working vehicle according to claim 1, wherein the rotation center of the link mechanism is arranged on the outer side of the machine body with respect to the rotation center of the operation arm.   An interlock release mechanism for releasing the steering interlock of the side clutch is provided at an intermediate portion of the steering interlock mechanism, and the interlock release mechanism is disposed on the inner side of the vehicle body from the inner end of the front wheel rotation locus. Item 3. The working vehicle according to Item 1 or 2.

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