JPH0741802B2 - Work vehicle - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a work vehicle such as a riding lawn mower and a snowplow.

(Prior Art) In a conventional work vehicle (for example, a riding lawn mower), a neutral return member that interlocks with a brake pedal depression operation and a control shaft of a transmission that rotates in association with the operation of the neutral return member There is a control arm provided with a transmission operating device for returning the transmission and the speed change lever connected to the control arm to a neutral state when the brake pedal is depressed (US Pat. 4496035 specification).

(Problems to be Solved by the Invention) Generally, neutral adjustment of a transmission is performed while operating an engine and observing rotation of an axle.

However, in the case of the conventional work vehicle, after the transmission is mounted on the vehicle body, the transmission operation device is mounted near the lower portion of the transmission and a part of the vehicle body frame, so neutral adjustment (neutral position adjustment) is assembled. It was difficult to do on the line, and the neutral adjustment was troublesome.

It is an object of the present invention to provide a work vehicle in which neutral adjustment can be easily performed and neutral adjustment is unnecessary after the transmission is mounted on the vehicle body.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a neutral return member that interlocks with a depression operation of a brake pedal and a control shaft of a transmission that interlocks with the operation of the neutral return member. A work vehicle equipped with a control arm for rotating, and equipped with a transmission operating device for returning each of the transmission and a shift lever connected to the control arm to a neutral state when the brake pedal is depressed. , The transmission is arranged between drive wheels, the neutral return member and a control arm are detachably attached to an upper portion of the transmission, the neutral return member, the brake pedal pivotally attached to the vehicle, and the control. A link mechanism connects the arm and the speed change lever pivotally attached to the vehicle.

(Operation) The transmission is arranged between the drive wheels as described above, the neutral return member and the control arm are detachably attached to the upper portion of the transmission, and the neutral return member, the brake pedal pivotally attached to the vehicle, and the control Since the arm and the shift lever pivotally attached to the vehicle are connected by the link mechanism, the transmission operating device (the neutral return member and the control arm) can be incorporated before the transmission is mounted on the vehicle body.
Therefore, neutral adjustment can be performed when motoring the transmission alone.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 2 is a side view showing a riding lawn mower according to an embodiment of the present invention, in which 1 is a body of the riding lawn mower, 2 is an engine arranged under a seat 3, and 4 is a side portion of the seat 3. The gear shift levers for traveling provided are respectively shown. The speed change lever 4 is attached to a speed change lever attachment device 5 which is rotated by the operation of the lever 4, and the attachment device 5 is connected to a hydraulic continuously variable transmission 7 via a link mechanism 6 (see FIG. 4). Has been done. By operating the speed change lever 4 before and after the neutral position (neutral position), the inclination of the swash plate 36 of the swash plate type variable displacement pump in the hydraulic continuously variable transmission 7 is controlled to control the traveling speed and direction of the vehicle body 1. It is supposed to be done. Further, a cutter deck 8 is provided below the vehicle body 1, and the cutter deck 8
A cutter blade 44, which is rotated by the input shaft of the hydraulic continuously variable transmission 7, is rotatably mounted therein, and a deck roller 46 for maintaining the minimum height of the cutter deck 8 is provided to the front, rear, left and right of the cutter deck 8. It is pivoted so that it can rotate individually, and it is possible to mow the lawn into strips while traveling at low speed. A guide panel (not shown) for guiding the shift lever 4 is provided above the shift lever mounting device 5. An operation guide groove (not shown) extending in the front-rear direction with respect to the vehicle body 1 is formed in the guide panel. The engine 2 and the battery 48 are fixed to the upper part of the body frame 47,
These are covered with a cover 49. The steering wheel 50 steers the front wheels 51. Wheels 52 are fixed to both ends of the axle 33. An oil tank 55 is arranged above the hydraulic continuously variable transmission 7.

As shown in FIGS. 5 and 6, the hydraulic continuously variable transmission 7 includes a swash plate type variable displacement pump 30, a single motor 31 driven by the pump 30, and a differential gear 32.
And an axle 33, an input shaft 34, and the like. The swash plate type variable displacement pump 30 includes a drive shaft 35 that is rotated by engine power via an input shaft 34, a swash plate 36 that is attached so as to be inclined with respect to the axis of the drive shaft 35, and the like. Gear shifting is performed by changing the inclination angle of the swash plate 36. A control shaft 7a is connected to the swash plate 36, and a tip portion of the control shaft 7a projects from the housing 37 to the outside. The brake mechanism includes a brake housing 39 provided on the board 19 and a brake shoe 40 supported by the brake housing 39.
And a cam 41 that expands the brake shoe 40.
Is connected to the brake pedal 12 via a brake arm 42 and a brake connecting rod 43.

As shown in FIG. 1, FIG. 3, FIG. 4 and FIG. 7, the transmission operating device has a control fixed to the control shaft 7a protruding above the hydraulic continuously variable transmission 7 by welding or the like. The arm 11, the bracket 20 bolted to the base plate 19 of the hydraulic continuously variable transmission 7, the bearing member 27 welded to the bracket 20, and the pivot 21 rotatably supported by the bearing member 27. And the neutral return member 18 to which the pivot 21 is welded, and the pins 24 and 25 welded to the neutral return member 18.
It has and. A pin 10 is provided at the free end of the control arm 11, and the pin 10 is connected to the speed change lever mounting device 5 via a changen rod 9. The control arm 11 rotates together with the control shaft 7a.
Therefore, the gear shift operation of moving the gear shift lever back and forth from the neutral position (neutral position) is performed by the gear shift lever mounting device 5.
Also, it is transmitted to the control shaft 7a via the link mechanism 6, and the tilt of the swash plate 36 is changed by the rotation of the control shaft 7a to control the traveling speed and direction of the vehicle body 1.

On the other hand, as shown in FIGS. 1, 3, 4, and 7, the brake pedal 12 is turned off together with the rotating member 13 in FIG.
The return member 14, the return member 15, the return rod 16, and the pin 17 are urged to rotate toward the position (the release position of the stepping operation) (in the direction indicated by the arrow A in FIG. 3). Is connected to the neutral return member 18 via the rod 13
It is connected to the brake system via a. The neutral return member 18 is bent at a bent portion 18a to avoid interference with the change rod 9 (see FIG. 7), and its lower side portion 18b is connected to the return rod 16 by a pin 17. . The upper portion 18c of the neutral return member 18 has a hydraulic continuously variable transmission 7
It is rotatably supported by a pivot 21 which is erected on a bracket 20 fixed to the upper part of a base plate 19 by a bolt 26. Therefore,
When the brake pedal 12 is depressed from the OFF position to the ON position (depressing operation position), the neutral return member 18 rotates from the original position shown by the chain line in FIG. 3 to the neutral return position (brake braking position) shown by the solid line, At this time, the brake device is operated via the rod 13a. Further, when the depression operation of the brake pedal 12 is released, the pedal 12 is returned to the OFF position by the urging force of a return spring (not shown), so that the neutral return member 18 also returns to the original position. The bracket 20 is provided with three long holes 20a, and the bolt inserted into the long hole 20a is screwed into a female screw (not shown) of the board 19 to fix the bracket 20 to the board 19 of the continuously variable transmission 7. It is fixed to the upper part of.

As shown in FIG. 3, the control arm 11 has
Two long grooves 22 and 23 are provided. On the other hand, the neutral return member 18 is provided with two pins 24, 25 corresponding to the long grooves 22, 23, and when the neutral return member 18 is rotated to the return position, the two pins 24, 25 are rotated. At least one of the control arms 11 engages with the ends of the corresponding long grooves 22 and 23.
The two long grooves 22 and 23 and the two pins 24 and 25 are arranged so as to return the to the neutral position. It should be noted that at least one of the pins 24, 25 is configured to contact the opposite ends of the two long grooves 22, 23 when the control arm 11 is returned to the neutral position.

As described above, since the structure in which the transmission operation device is detachably attached to the upper portion of the hydraulic continuously variable transmission 7 via the bracket 20 is adopted, before mounting the hydraulic continuously variable transmission 7 on the vehicle body,
A transmission operating device can be incorporated. Therefore,
Neutral adjustment is possible when motoring the hydraulic continuously variable transmission alone. That is, first, the control arm 11 is rotated in both forward and backward directions to determine the neutral position (neutral position), and then, as shown in FIG.
The neutral return member 18 is rotated so that the neutral adjustment is performed so that 24 and 25 hit the opposite ends of the long grooves 22 and 23 of the control arm 11. After that, the hydraulic continuously variable transmission 7 is mounted on the vehicle body, the link mechanism 6 is assembled, and the length of the change rod 9 is adjusted in accordance with the neutral position of the control arm 11 which was previously adjusted when the hydraulic continuously variable transmission 7 was assembled. Adjusting the height, and with the brake pedal 12 depressed to the ON position, the pins 22 and 23 of the neutral return member 18 are engaged with the long groove 22 of the control arm 11.
The length of the return rod 16 may be adjusted so that it hits 23 at the same time. Therefore, the troublesome neutral adjustment after mounting the hydraulic continuously variable transmission 7 on the vehicle body becomes unnecessary, and at the same time, the mountability on the vehicle body is improved.

As described above, according to the work vehicle of the present invention, the neutral return member that interlocks with the depression operation of the brake pedal, and the control shaft of the transmission that rotates in conjunction with the operation of the neutral return member. A work vehicle equipped with a control arm for causing the transmission and the gear shift lever connected to the control arm to return to a neutral state when the brake pedal is depressed. A transmission is disposed between drive wheels, the neutral return member and a control arm are detachably attached to an upper portion of the transmission, the neutral return member, the brake pedal pivotally attached to the vehicle, and the control arm. Before mounting the hydraulic continuously variable transmission on the vehicle body, the speed change levers pivotally attached to the vehicle were connected by a link mechanism. A transmission operating device can be incorporated, and neutral adjustment can be performed when motoring the hydraulic continuously variable transmission alone. Therefore, the troublesome neutral adjustment after mounting the hydraulic continuously variable transmission 7 on the vehicle body becomes unnecessary, and at the same time, the mountability on the vehicle body is improved. Also, since the neutral return member that works in conjunction with the brake pedal can be incorporated and adjusted in the transmission case separately from the vehicle body, it is easy to assemble and disassemble the transmission to the vehicle body frame. Also, the arrangement of the transmission operating device including the neutral return member, the control arm, etc. is simple,
There is sufficient strength and rigidity of the connecting members such as the return rod and the change rod that form the link mechanism, and the durability can be improved. Furthermore, since the transmission operating device is not attached to the vehicle body frame but is detachably attached to the upper part of the transmission, it is not necessary to remove the transmission or the transmission operating device from the vehicle body when performing maintenance. It also enables easy maintenance.

[Brief description of drawings]

1 is a rear view showing a riding lawn mower according to an embodiment of the present invention, FIG. 2 is a side view showing the entire riding lawn mower, and FIG. 3 is a view for explaining the operation of a transmission operating device. Figure, No. 4
FIG. 5 is a side view showing a connecting structure between a speed change lever and a control arm and a connecting structure between a brake pedal and a neutral return member, FIG. 5 is a vertical sectional view of a hydraulic continuously variable transmission, and FIG. FIG. 7 is a schematic view showing a main part of the riding lawn mower shown in FIG. 4 ... shift lever, 7 ... hydraulic continuously variable transmission (transmission),
11 …… Control arm, 12 …… Brake pedal, 18
...... Neutral return member.

Claims (1)

[Claims] 1. A neutral return member that interlocks with a depression operation of a brake pedal, and a control arm that rotates a control shaft of a transmission in conjunction with the operation of the neutral return member. When the brake pedal is depressed. A work vehicle equipped with a transmission operating device for returning the transmission and a transmission lever connected to the control arm to a neutral state, wherein the transmission is arranged between drive wheels, and the neutral return member is provided. And a control arm are detachably attached to the upper portion of the transmission, and the neutral return member and the brake pedal pivotally attached to the vehicle, and the control arm and the transmission lever pivotally attached to the vehicle are respectively linked by a link mechanism. Work vehicle characterized by being connected.