JPH0565371B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention provides a foot pedal and a manual lever for operating a hydraulic continuously variable transmission for driving, and acts on the manual lever to control the hydraulic pressure. The present invention relates to a driving operation structure for a work vehicle that is provided with a friction mechanism that maintains a continuously variable transmission in a transmission state.

[Conventional technology]

The above-mentioned work vehicle is designed so that the speed can be easily adjusted while traveling by using a foot pedal when traveling on the road, etc. Furthermore, during work, the hydraulic continuously variable transmission can be adjusted to the desired speed using a manual lever. It is adjusted and fixed by a friction mechanism,
It was designed to facilitate constant speed driving.

Conventionally, in this type of work vehicle, when using a foot pedal, it is necessary for safety to ensure that the pedal returns to the neutral position when the pedal is released, so the friction mechanism is not used to brake the foot pedal. In order to make it possible to switch to the above, for example, the configuration was as shown in Japanese Utility Model Publication No. 61-22017. That is, a clutch mechanism is provided between the lever side member and the transmission side member that constitute the interlocking mechanism of the manual lever and the hydraulic continuously variable transmission, and this clutch mechanism is operated by a dedicated operating lever. As a result, the manual lever is disengaged from the continuously variable transmission, and the friction mechanism no longer acts on the foot pedal operation system.

[Problem that the invention seeks to solve]

In the conventional case, two operating levers were required, one for manual shifting and one for switching between enabling and disabling fixed speed, which was not only disadvantageous in terms of structure, but also caused problems between the fixed speed and the pedals. In order to change the state of use, the troublesome effort of manipulating two operating levers was required.

An object of the present invention is to provide an operating structure that is advantageous both in terms of structure and in terms of operation.

[Means for solving problems]

The characteristic configuration of the present invention is that a foot pedal and a manual lever are provided for operating the hydraulic continuously variable transmission for traveling, and a friction mechanism is provided that acts on the manual lever to maintain the hydraulic continuously variable transmission in a transmission state. In the operating structure for running a work vehicle provided, the manual lever is attached so as to be operable in a second moving direction different from the first moving direction for operating the hydraulic continuously variable transmission, and the manual lever side member forming a friction mechanism is provided. The manual lever side member and the manual lever are connected so that the manual lever moves integrally with the manual lever operated in the first moving direction, and the manual lever operated in the second moving direction is allowed to move independently. A clutch mechanism for switching a manual lever between an interlocking state and a disengagement state with respect to a continuously variable transmission is connected to a clutch device and a manual lever that are interlocked with a rotary operating shaft of a hydraulic continuously variable transmission, and is engaged with a plate portion and these plate portions. Clutch pins that can be arranged are distributed and arranged, and the interlocking state in which the clutch pin and the plate part are engaged, and the disengaged state in which the clutch pin and the plate part are disengaged are controlled by a manual lever. When the clutch mechanism is in the engaged state, the plate portion for forward operation of the plate portions is configured to be freely exposed by operation in the second movement direction.
The hydraulic continuously variable transmission is provided with a flexible portion that allows the clutch to be operated in a direction toward higher speeds, and its functions and effects are as follows.

[Effect]

When the manual lever is operated in the second movement direction, the clutch mechanism is engaged and the manual lever is linked to the hydraulic continuously variable transmission. The clutch mechanism is disengaged, the manual lever is no longer linked to the hydraulic continuously variable transmission, and the friction mechanism no longer acts on the foot pedal.

Further, the flexible portion formed in the forward movement plate allows the vehicle to move forward at a speed faster than the set speed by operating the foot pedal even when the forward travel speed is set using the manual lever.

〔Effect of the invention〕

Since the manual lever for manual gear shifting is used as the operating lever for switching between a state in which the speed can be fixed and a state in which the gear can be changed using the foot pedal,
The number of operating levers is smaller than before, making the structure simpler and more economical.In addition, switching between fixed speed and pedal use can be done by using only a manual lever. Easy to operate,
It has also become superior in terms of operation.

Also, for example, when mowing with a tractor, when passing through a place where there is no grass, you may want to move through it at high speed from the viewpoint of work efficiency.
There are times when it is desired to temporarily run at high speed, but with the present invention, when moving forward at a constant speed using the manual lever, it is possible to achieve even higher speed forward movement using the foot pedal, which is convenient in actual work. There are some advantages.

〔Example〕

As shown in FIG. 11, a lawn mowing device 2 is connected between the front and rear wheels of a wheeled traveling body through a link mechanism 1 so as to operate up and down, and a lawn mowing device 2 is connected to the front and rear wheels of a wheeled traveling body so that power is transmitted from the traveling body to the lawn mowing device. A riding type lawn mower is constructed.

In order to enable the traveling operation of the traveling aircraft, a hydraulic continuously variable transmission 5, which is interlocked and connected to the engine 3 so as to transmit power through the rotating shaft 4, is attached to the transmission case 6, and a rear wheel transmission (Fig. (not shown), the brake 7 for running is connected to the rear wheel 8.
The operation structure of the continuously variable transmission 5 and the brake 7 is shown in FIG.
It is constructed as shown in FIGS. 2 and 7.

That is, the control section is configured to swing the foot-operated variable speed pedal 11, which is linked to the rotary operation shaft 5a of the hydraulic continuously variable transmission 5 via the swing linkage device 9, the linkage rod 10, etc., around the axis _P1 . It is located at 12.
When the shift pedal 11 is operated by pressing the front operating section 11a, the hydraulic continuously variable transmission 5 is switched from the neutral state to the forward side, and when the shifting pedal 11 is depressed and operated using the rear operating section 11b, the hydraulic continuously variable transmission 5 is switched from the neutral state to the forward side. The continuously variable transmission 5 is switched from the neutral state to the reverse side, and the hydraulic continuously variable transmission 5 is set to the high speed side as the depression stroke of the shift pedal 11 becomes larger in each of the forward and reverse sides. be. A cam plate 13 is attached to the swing interlocking tool 9 so as to swing together, a link 14 is pivotally mounted to the transmission case 6 so as to swing around an axis _P2 , and a roller portion of this link 14. 14a is pressed against the cam surface 13a of the cam plate 13 by a cam-type biasing mechanism consisting of a spring 15 etc. that swings and biases the link 14, and by the self-restoring force of the hydraulic continuously variable transmission 5. , the rotary operation shaft 5a and the speed change pedal 11 are biased so as to automatically return to the stop position when the operation is released.

Further, the manual lever 16 for operating the hydraulic continuously variable transmission 5 is connected to the lever support member 17 around the axis of the support shaft 18 via the lever support member 17 and the support shaft 18, as shown in FIG. It is attached to the cylindrical boss portion 19a of the fuselage frame portion 19 so as to swing together in the longitudinal direction of the fuselage. The manual lever 16
is slidably attached to the lever support member 17 so that it can be moved in the lateral direction of the aircraft body, and is turned on and off by moving the manual lever 16 in the lateral direction of the aircraft body, and the hydraulic continuously variable transmission is operated. A clutch mechanism 20 for switching the manual lever 16 between an interlocked state in which it can be operated and a disengaged state is constructed as shown in FIGS. 1 and 2. That is, when the manual lever 16 is interlocked with the clutch pin 22 provided at a portion of the manual lever 16 that enters the inside of the machine body through the elongated hole 21 of the machine body frame portion 19 and the swing linkage tool 9 via the linkage rod 23, When the manual lever 16 is slid in the lateral direction of the fuselage, the clutch pin 22 is moved to the clutch tool 24 as shown in FIGS. 3 and 5. The first plate portion 24 of
When the clutch pin 22 enters into the notch 25 of a and is operated, the clutch pin 22 contacts the abutted portion 2 of the first plate portion 24a.
6, the clutch device 24 is swung in the direction of the arrow f due to the swiveling force of the manual lever 16, and the rotary operating shaft 5a is moved to the forward side, thereby entering the forward movement state. As shown in FIGS. 4 and 5, when the clutch pin 22 enters the notch 27 of the second plate portion 24b of the clutch tool 24 and is operated,
The clutch pin 22 acts on the abutted portion 28 of the second plate portion 24b, and due to the swing operation force of the manual lever 16, the clutch tool 24 is swing operated in the direction of arrow r, and the rotary operation shaft 4 is moved to the reverse side. When the clutch pin 22 is removed from both the first plate portion 24a and the second plate portion 24b as shown in FIG. 1, the operating force of the manual lever 16 is reduced. It is set to be in the off state so that it is not transmitted. The clutch mechanism 20 is biased by a spring 29 acting on the manual lever 16.
A pin guide 30 as shown in FIG. 9, which acts on the clutch pin 22, is attached to the fuselage frame portion 19. The lever support member 17 and the support shaft 1
8, a friction plate 32 disposed between the press tool 31 and the lever support member 17, and between the lever support member 17 and the body frame portion 19, and a support shaft 18. Each of the coil springs 33 fitted on the outside constitutes a friction mechanism 34 that acts on the manual lever 16 so as to provide frictional resistance to the swinging of the manual lever 16 in the longitudinal direction of the machine body. That is, spring 3
3 presses the friction plate 32 and the lever support member 17 against the fuselage frame portion 19 through the pressing tool 31, and the lever support member 1 is pressed by the action of the friction plate 32.
Frictional resistance is applied to the rotation of 7.

In short, when the manual lever 16 is slid along the first guide groove portion 36a of the lever guide 35 in the lateral direction of the aircraft body as shown in FIG. Then, the manual lever 16 is moved to the second guide groove portion 36 in the longitudinal direction of the machine.
When the hydraulic continuously variable transmission 5 is swung in the direction opposite to the first guide groove portion 36a along the direction b, the hydraulic continuously variable transmission 5 enters the forward transmission state, and the hydraulic continuously variable transmission 5 is moved along the third guide groove portion 36c in the longitudinal direction of the aircraft. When the swinging operation is performed to the side opposite to the first guide groove portion 36a, the hydraulic continuously variable transmission 5
becomes the reverse transmission state. The hydraulic continuously variable transmission 5 can be maintained in the transmission state by the friction mechanism 34 acting through the manual lever 16 and the operating system thereof on each of the forward and reverse sides, and even in this maintenance state, The first plate portion 24a and the second plate portion 24
b each notch 25 or 27 [corresponding to flexible part]
Due to the effect of the length l, it is possible to perform a speed change operation using the speed change pedal 11 at a higher speed than the maintenance speed. Then, when the manual lever 16 is operated to the operating position S and the clutch mechanism 20 is kept in the disengaged state,
This allows the hydraulic continuously variable transmission 5 to be operated using the speed change pedal 11 while making it impossible for the speed change pedal 11 to be fixed by the friction mechanism 34.

As shown in FIG. 7, a brake pedal 40, which is interlocked with the swingable operating arm 7a of the brake 7 via an interlocking rod 37, a rotary shaft 38, an interlocking rod 39, etc., is swung around an axis _P3 . It is provided in the control section 12 so as to do so.

An operating arm 41 for releasing the friction mechanism 34 is rotatably attached to the rotating shaft 38, and the friction mechanism 34 is automatically released by simply operating the brake 7 to control the speed using the manual lever 16. It is configured so that it can be unlocked. That is, when the brake pedal 40 is depressed, the operating arm 41 swings from the non-operating position (OFF) shown by the solid line in FIG. The support shaft 18 is rotated by a set angle by contacting the arm 42. Then, due to the rotation of the support shaft 18 and the action of the cam portion 18a provided on the support shaft 18 on the cam portion 31a of the pressing tool 31, the support shaft 18 separates the pressing tool 31 from the lever support member 17. By sliding it toward the side, the lever support member 17 is released from being pressed against the body frame portion 19 by the spring 33.

[Another example]

The specific configuration of the friction mechanism can be changed in various ways, and the lever support member 17 is referred to as a manual lever side member 17.

The operating direction of the manual lever 16 for operating the hydraulic continuously variable transmission device 5 may be set to a vertical direction other than the longitudinal direction of the aircraft body, and the longitudinal direction of the aircraft body may be set as the first moving direction. The lateral direction of the aircraft is referred to as the second moving direction.

In addition to lawn mowers, the present invention can also be applied to various work vehicles such as agricultural tractors, combines, and transport vehicles.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

The drawings show an embodiment of the operation structure for driving a working vehicle according to the present invention, in which FIG. 1 is a partially cutaway front view of the transmission operation structure, FIG. 2 is a side view of the transmission operation structure, and FIG. 3 is a side view of the transmission operation structure. and FIG. 4 is a sectional view of the clutch mechanism,
Figures 5 and 6 are side views of the clutch mechanism;
The figure is a perspective view of the brake operation structure, Fig. 8 is a plan view of the lever guide, Fig. 9 is a plan view of the pin guide,
Figure 10 is a cross-sectional view taken along the line X-X in Figure 1, and Figure 11.
The figure is a side view of a riding lawn mower. 5... Hydraulic continuously variable transmission, 5a... Rotating operation shaft, 11... Foot pedal, 16... Manual lever, 17... Manual lever side member, 20... Clutch mechanism, 22... Clutch pin, 24a, 24b
...Plate part, 34...Friction mechanism.

Claims (1)

[Scope of Claims] 1. A foot pedal 11 and a manual lever 16 are provided for operating the hydraulic continuously variable transmission 5 for traveling, and the manual lever 16 is actuated to transmit the hydraulic continuously variable transmission 5. Friction mechanism 3 to maintain the condition
4, the manual lever 16 is mounted so as to be operable in a second moving direction different from the first moving direction for operating the hydraulic continuously variable transmission 5, A manual lever side member 17 constituting the friction mechanism 34 moves integrally with the manual lever 16 operated in the first movement direction,
and the manual lever side member 17 and the manual lever 16 are connected so as to permit independent movement of the manual lever 16 operated in the second movement direction, and the linked state with respect to the hydraulic continuously variable transmission 5 is established. The clutch mechanism 20 that switches the manual lever 16 between
Plate portions 24a, 24 are attached to the clutch tool 24 and the manual lever 16 which are interlocked with the rotary operation shaft 5a.
b and a clutch pin 22 that can engage with these plate portions 24a and 24b are distributed and arranged,
and the clutch pin 22 and the plate portion 2
4a, 24b are engaged, and the clutch pin 22 and the plate portions 24a, 2
The interlock release state in which the occlusion with the plate parts 24a and 4b is released can be brought about by operating the manual lever 16 in the second movement direction, and the plate parts 24a and 24b are moved forward. The clutch mechanism 2 is attached to the plate portion 24a for
This operating structure for running a work vehicle is formed with a flexible portion 25 that allows the clutch tool 24 to be operated in a direction in which the hydraulic continuously variable transmission 5 is operated to a higher speed side when the clutch is engaged at zero.