JPH0626947B2 - Operation structure for traveling of work vehicle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention provides a speed lock mechanism for holding a traveling continuously variable transmission that can automatically restore a transmission stopped state in a transmission state in a releasable manner. Work in which an interlocking mechanism that interlocks the steering brake pedal and the speed lock mechanism is provided so that the speed lock mechanism is automatically released only when any of the steering brake pedals is depressed. The present invention relates to a vehicle driving operation structure.

[Conventional technology]

The above work vehicle can hold the traveling continuously variable transmission in the transmission state by the speed lock mechanism regardless of the restoring force to the transmission stopped state at the time of work, and the constant speed traveling can be performed without manual operation for this holding. It is designed so that it can be done. Moreover, when the vehicle is turning by depressing only one of the left and right steering brake pedals at the time of constant speed traveling, the speed lock mechanism is maintained in the operating state and the continuously variable transmission for traveling. The speed lock mechanism is automatically released due to the interlocking mechanism when the aircraft is stopped by depressing both the left and right steering brake pedals. In consideration of the fact that the continuously variable transmission for traveling is brought into a transmission stopped state and the aircraft quickly stops.

In this type of work vehicle, the interlocking mechanism has conventionally been constructed as shown in FIG. That is, one side is connected to one steering brake pedal (26) by the pedal side interlocking tool (28a), and the other end is connected by the other steering brake pedal (27) and the pedal side interlocking tool (28b). Interlocking link (2
9) is provided and the lock mechanism side interlocking device pivotally attached to the interlocking link (29) located between the pedal side interlocking device couplings.
The interlocking link (29) was connected to the release operation part (25) of the speed lock mechanism (22) by (30), and only one steering brake pedal (26) or (27) was stepped on. In the state, the interlocking link (29) is connected to the steering brake pedal (26) or
Due to the depression operation force of (27), the pedal-side interlocking device (28b) of the other steering brake pedal (27) or (26) or
(28a) is pivotally operated around the pivot axis (P ₅ ) or (P ₄ ) in the state shown by the broken line, and the connection point (34) of the lock mechanism side interlocking device (30) to the interlocking link (29) Moves a distance (l) from the position before the pedal is depressed and the release operation part (25) is slightly stroked, but the release operation part (25) is still in the non-acting position, and the left and right steering brake pedals are operated. In the state where both (26) and (27) are stepped on, the interlocking link (29) is moved in parallel to the state shown by the phantom line, and the connecting point (34)
Is operated so that the release operation part (25) is operated to the operating position by moving a distance (L) larger than the distance (l) from the position before pedal depression.

[Problems to be Solved by the Invention] In the conventional case, one steering brake pedal (26) or (2
When the single brake is operated in which only 7) is stepped on, the moving distance (l) of the connecting portion (34) is the steering brake pedal.
It is large for the stepping stroke of (26) or (27), and it is necessary to prevent the speed lock mechanism (22) from switching to the released state during one-sided brake operation. The stepping operation stroke from the brake applied position to the brake applied position in (26) and (27) was relatively small.

An object of the present invention is to make the operation stroke of the steering brake pedal relatively large.

[Means for solving problems]

According to a characteristic configuration of the present invention, in the operating structure for traveling of a work vehicle described above, one of the steering brake pedals is connected to one of the steering brake pedals by a pedal side connecting tool pivotally attached at one end to the interlocking mechanism. And a lock having one end side connected to the release operation part of the speed lock mechanism by providing an interlocking link connecting the other end side to the other steering brake pedal by a pedal side interlocking tool pivotally attached to the location. The other end of the mechanism-side interlocking device is slidably connected to the interlocking link in the parallel direction of the pedal-side interlocking device, and the locking mechanism-side interlocking device is urged in the direction in which the release operation portion is in the non-acting position. In the state where only one of the steering brake pedals is depressed, the interlocking link swings around the pivotal axis of the pedal-side interlocking tool of the other steering brake pedal. Operated by The lock mechanism side interlocking tool slides on the pivot center side of the interlocking link, the release operation part is in the non-acting position, and any one of the steering brake pedals is depressed. , The interlocking link is translated in the same direction as the swinging direction when only one of the steering brake pedals is stepped on to operate the release operation part to the operating position via the lock mechanism side interlocking device. It is something like that. The action and effect are as follows.

[Action]

Even if the left and right steering brake pedals are both stepped on, the distance that the connecting portion of the interlocking link of the lock mechanism side moves will be the same as before when both brakes are operated. When one-sided brake operation is performed, the lock mechanism side interlocking tool slides toward the center of the swing of the interlocking link due to the swinging of the interlocking link and the biasing force of the spring, and the connecting point moves. The distance can be made smaller than before. In other words, the movement distance of the connecting portion during one-side braking is small in comparison with the stepping operation stroke of the steering brake pedal. It is possible to prevent the speed lock mechanism from switching to the released state during operation.

〔The invention's effect〕

Sliding the lock mechanism side interlocking device against the interlocking link makes it possible to expand the operation stroke of the steering brake pedal, and it is easy to adjust the braking force of the brake by adjusting the amount of operation of the brake pedal. It became easy to adjust the.

〔Example〕

 Next, examples will be shown.

As shown in FIG. 3, a lift arm (1) for connecting various working devices such as a rotary cultivator to the rear part of the wheel-type traveling vehicle so as to be able to move up and down, and a power take-out for transmitting to the connecting work device. A shaft (2) is attached to construct an agricultural tractor.

The output of the engine (E) is transmitted to the front wheels (4) and the rear wheels (5) via a traveling hydraulic continuously variable transmission (3) that can switch between a forward state and a reverse state by sandwiching the neutral state. It is configured as follows. Then, as shown in FIG. 2, the rotary operation shaft (3a) of the continuously variable transmission (3) is provided with a swing interlocking device (6) and a connecting rod.
(7) and gearshift operation pedal (10) linked by rotating shaft (8)
Is mounted on the traveling machine body so as to swing around the axis of the rotary shaft (8), and at the same time, the continuously variable transmission (3)
The cam roller (12), which is swingably attached to the rocking support link (11), is urged by the spring (13) against the cam portion (6a) of the rocking interlocking device (6). The mechanism and the neutral restoring force of the continuously variable transmission itself are urged to automatically restore each of the continuously variable transmission (3) and the speed change operation pedal (10) to the neutral state. Then, as shown in FIG. 1, a plurality of locking plates (15), which are interlocked with the rocking interlocking device (6) by interlocking the interlocking rod (14), are attached to the case (1
6) via the support shaft (17), which is mounted non-rotatably, via the support shaft (17) so that it can swing, and the operation cam (18), the sliding only lock tool (19), the coil spring (20) ) And a plurality of friction plates (21) are attached to the continuously variable transmission (3) to maintain its transmission state against the neutral restoring force of the continuously variable transmission and the restoring mechanism. The mechanism (22) is configured. That is, when the operation lever (23) attached to the operation cam (18) so as to be able to rotate integrally is rocked to the lock position (ON), the operation cam (18) has a side projection of the lock member (1).
The lock tool (19) slides toward the coil spring (20) to increase the biasing force of the coil spring (20), which causes the coil spring (20) to lock. When the plate (15) and the friction plate (21) are pressed against the receiving member (24), the locking plate (15) swings regardless of the self-restoring force of the continuously variable transmission (3) and the acting force of the restoring mechanism. It is in a state of being actuated so as to be frictionally braked so as not to be moved.
Then, the operation lever (23) is rocked to the release position (OFF), or the release operation part (25) provided integrally with the operation cam (18) is swingable to the operation position (OFF). When it is operated, the operation cam (18) has the side projection of the lock (19).
The lock tool (19) is pushed into the operation cam (18) by the coil spring (20) to reduce the biasing force of the lock plate (15). The pressure contact with the receiving member (24) is released, and the lock plate (15) is released so that frictional braking of the plate (15) is reduced.

That is, on the road, the speed lock mechanism (22) is kept in the released state, and the continuously variable transmission using the speed change operation pedal (10).
The forward / backward movement and the traveling speed change operation of the aircraft are performed by the switching operation and the speed change operation in (3). Then, at the time of work, the continuously variable transmission (3) is operated at the desired speed and the speed lock mechanism (22) is operated so that the continuously variable transmission (3) is at the desired speed. The constant-speed running can be performed at a desired speed without performing a depression maintaining operation of the speed change operation pedal (10) for holding the pedal.

As shown in FIGS. 1 and 2, the left and right rear wheels (5), (5)
The pair of steering brakes (B ₁ ) and (B ₂ ) that act separately on each side can be operated separately and are mounted on the traveling machine body so as to swing around the axis (P ₁ ). One of the pair of left and right steering brake pedals (26), (27) is connected to one of the rod-side pedal-side interlocking devices.
(28a) and on the other hand, pedal-side interlocking device made of rod
(28b) connects the interlocking links (29) to each other, and the interlocking links (29) are connected to the release operation part (25) by the lock mechanism side interlocking tool (30) made of a rod and the lock mechanism side interlocking Spring (31) that biases the tool (30) toward the rear of the machine
To the end of the lock mechanism side interlocking device (30) so that the left and right steering brake pedals (26, (27) are both depressed when the speed lock mechanism (22) is in operation. An interlocking mechanism (32) in which the steering brake pedals (26) and (27) and the speed lock mechanism (22) are interlocked with each other is configured to be automatically released only at.

That is, one end side of each of the pedal side interlocking devices (28a) and (28b) has a boss portion (26a) of the left steering brake pedal (26) or a boss portion (27a) of the right steering brake pedal (27). ) Is pivotally attached so as to swing around the axis (P ₂ ) or (P ₃ ) in the lateral direction of the machine body, and the other end is one end side of the interlocking link (29) in the lateral direction of the machine body. Alternatively, it is pivotally attached to the other end side so as to swing around the axis (P ₄ ) or (P ₅ ). Lock mechanism side interlocking tool
One end side of (30) is a long hole (33) in the lateral direction of the machine body formed between pedal side interlocking device connection of interlocking link (29) and connecting pin (34) slidably inserted in this long hole (33). Link link with (29)
Is connected to the pedal side interlocking device (28a) and (28b) so that they can slide in the parallel direction, and the other end side is the release operation part (25).
So that it can be swung around the axis axis in the lateral direction of the machine body (P ₆ ), and can be swung in the direction along the swing axis axis of the release operation part (25) for connection flexibility. It is connected. When only one steering brake pedal (26) or (27) is depressed by the braking device (A), this operation force causes the interlocking link (29) to operate the other non-operating steering. break pedal
(27) or (26) pedal side interlocking device (28b) or (28a)
Pivot axis of the (P ₅₎ or (P ₄₎ steered brake pedal in a state shown by broken lines in FIG. 1 around (26) is swung towards the (27), the coupling link The lock mechanism side interlocking device (30) slides toward the pivot center of the interlocking link (29) due to the swinging motion and the pulling action of the spring (31), and the lock mechanism side interlocking device (30). The connecting pin (34), which is the connecting point for the interlocking link (29) of (1), moves a distance (l) from the position before the braking operation to the steering brake pedals (26), (27), and the lock mechanism side The interlocking tool (30) moves the release operation part (25) to the operating position (OFF)
Stroke a little toward the operator, but release operation part (25)
The operating cam (18) is in a substantially non-acting position so that the side projection of the operating cam (18) still rides on the side projection of the lock (19). And the left and right steering brake pedals
When both (26) and (27) are stepped on to the braking position (A), this operation force causes the interlocking link (29) to move to the state shown in phantom in FIG. Pedals (26),
The connecting pin (34) is moved parallel to (27) so that the connecting pin (34) is a distance larger than the distance (l) from the position before the braking operation.
(L) and move the interlocking link (29) to the locking mechanism side interlocking device (3
The release operation part (25) is pulled to the operating position (OFF) via 0).

In other words, when the vehicle is traveling at a constant speed using the speed lock mechanism (22), the speed lock mechanism is used when only one steering brake pedal (26) or (27) is braked to make a turning operation. Although the mechanism (22) is maintained in the operating state, when the operation of stopping the aircraft is stopped by braking either of the left and right steering brake pedals (26) and (27), the speed lock mechanism ( 22) is automatically switched to the released state, the continuously variable transmission (3) is switched to the neutral state, the wheel drive is stopped, and the aircraft quickly stops traveling.

[Another embodiment]

The present invention can be applied to a case where a belt type continuously variable transmission is adopted instead of the hydraulic continuously variable transmission (3), and these are simply referred to as traveling continuously variable transmissions (3), and are in a neutral state. Is called a transmission stopped state.

When the steering brake pedals (26) and (27) are stepped on, the interlocking link (29) is provided on the opposite side of the release operation section (2) from the above embodiment.
It may be configured so as to swing toward 5) or move in parallel.

In the embodiment shown in FIG. 1, the connecting pin (34) is provided with a long hole (3
Although it does not adopt the structure to urge the restoring force in the middle of 3), only one steering brake pedal is depressed and the connecting pin (34) slides to the one end side of the interlocking link (29) to operate. Even if the connecting pin (34) remains on one end of the interlocking link (29) even after the directional brake pedal is released, the next time only the other steering brake pedal is depressed. , Since the inclination direction of the interlocking link (29) at this time is opposite to that at the time of the previous one-brake operation, the connecting pin (34)
Slides securely to the other end of the interlocking link (29). Therefore, although there is no problem even if there is no special restoring biasing structure, the restoring force may be exerted by making the elongated hole (33) into a curved shape or by causing a spring to act.

The present invention can be applied to various work vehicles such as lawn mowers and transport vehicles as well as agricultural tractors.

It should be noted that reference numerals are added to the claims for convenience of comparison with the drawings, but the present invention is not limited to the structures of the accompanying drawings by the entry.

[Brief description of drawings]

The drawings show an embodiment of an operating structure for traveling of a work vehicle according to the present invention. Fig. 1 is a plan view of an interlocking mechanism of a speed lock mechanism and a steering brake pedal, and Fig. 2 is a hydraulic type continuously variable transmission for traveling. FIG. 3 is a side view of the device operating structure, and FIG. 3 is a side view of the entire agricultural tractor. FIG. 4 is a plan view of a conventional interlocking mechanism. (3) …… Continuous transmission for traveling, (22) …… Speed lock mechanism, (25) …… Release operation part, (26), (27) …… Brake pedal for steering, (28a), ( 28b) …… Pedal side interlocking device, (29) ……
Interlocking link, (30) …… Lock mechanism side interlocking tool, (31) …… Spring, (32) …… Interlocking mechanism, (OFF) …… Operating position,
(P ₄ ), (P ₅ ) …… Pivot axis core.

Claims (1)

[Claims] 1. A speed lock mechanism (22) for holding a continuously variable transmission (3) for traveling, which can be automatically restored to a transmission stopped state, in a transmission state.
The speed lock mechanism (22) is automatically released only when the pair of left and right steering brake pedals (26), (27) is depressed. An operating structure for traveling of a work vehicle provided with an interlocking mechanism (32) that interlocks the brake brake pedals (26), (27) with the speed lock mechanism (22), and constitutes the interlocking mechanism (32). The pedal-side interlocking device (2
8a) is connected to one of the steering brake pedals (26), and the other end is pivotally attached to the location.
8b) is provided with an interlocking link (29) connected to the other steering brake pedal (27), and one end side is connected to the release operation part (25) of the speed lock mechanism (22).
The other end of (30) is slidably connected to the interlocking link (29) in the parallel direction of the pedal-side interlocking devices (28a), (28b), and the release operating portion (25) is in the non-operating position. A spring (31) for urging the locking mechanism side interlocking device (30) is provided in a direction to rotate the interlocking link (29) in a stepping operation state of only one of the steering brake pedals (26 or 27). The other pedal-side interlocking device (2) of the other steering brake pedal (27 or 26)
(8b or 28a) is pivotally operated around the pivot axis (P ₅ or P ₄ ), and the lock mechanism side interlocking device (30) moves the interlocking link (2
9) Sliding toward the center of the swing, the release operation part (25) is in the non-operating position, and the operation brake pedal (26), (27) is depressed. In the state, the interlocking link (29) is translated in the same direction as the swinging direction in the stepping operation state of only one of the steering brake pedals (26 or 27), and the interlocking device (30) on the locking mechanism side. An operating structure for traveling of a working vehicle, wherein the release operation part (25) is operated to an operating position (OFF) via a.