JPH1159478A - Differential traveling device for crawler type working vehicle - Google Patents

Abstract

(57) [Summary] (Modifications required) [Problem] To simplify the operation by concentrating the turn operation on a round handle instead of the conventional lever, distinguishing it from the lever that shifts the vehicle speed, and operating compared to the conventional lever Reduces power and facilitates operation of the work vehicle. When turning a combine in a left direction, a round handle is turned to the left to turn an operating piece position detection switch.
L is turned on, the side clutch shift fork 52L is moved to the left, and the left output gear 48 is separated from the straight running gear 47. Then, the left switching clutch 40 is turned on and the right switching clutch 41 is turned off to rotate the continuously variable transmission shaft 38 via the tenth transmission gear 53 to the left crawler drive shaft 1.
Transfer to 2L.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a differential traveling device for a crawler-type work vehicle such as a combine or a harvester having a transmission for independently transmitting the output of an engine to left and right crawlers.

[0002]

In order to change the course of a crawler-type work vehicle, in addition to a basic brake turn for braking by turning one of the right and left crawlers, the left and right crawlers are rotated in opposite directions. There are three methods: a spin turn that turns by turning, and a mild turn that turns by decelerating one of the left and right crawlers.

Conventionally, for these turns, a switch for selecting a turn mode between a spin turn and a mild turn is separately provided, and a switching lever for switching the switch, a clutch connection of a crawler tilting left and right and turning inward in a turning direction, and the like. It was executed using the steering lever that controls the brake.

[0004] In addition to the levers for operating these turns, there are also HST (hydrostatic continuously variable transmission) levers and auxiliary transmission levers for shifting the vehicle speed, and all these operations are performed by levers, so that the operation is complicated. And it made driving difficult. Also, the steering lever required a large operating force to tilt.

Therefore, the present invention consolidates the turning operation in a round handle in place of the conventional lever, simplifies the operation separately from the lever for shifting the vehicle speed, and reduces the operating force as compared with the conventional lever. It is intended to facilitate the operation of the work vehicle.

[0006]

In order to achieve the above object, the present invention is configured as follows.

That is, in a crawler-type work vehicle having a mission for independently transmitting the output of the engine to the left and right crawlers of the machine, a straight shaft for transmitting the output of the engine in the straight traveling direction, and a forward shaft for transmitting the output of the engine to the mission. A continuously variable shaft that continuously changes the speed from rotation to reverse rotation and transmits the transmission;
A pair of left and right side clutches that disconnect one of the left and right crawlers from the straight-moving shaft and connect to the continuously variable transmission shaft;
Side clutch switching means for rotating the rotary steering operation tool to switch the side clutch; and a continuously variable transmission shaft for rotating the rotary steering operation tool to control the rotation speed and direction of the continuously variable transmission shaft. Control means for connecting the outside of the left and right crawlers in the turning direction to the straight-moving shaft, and connecting the inside of the turning direction to the continuously variable transmission shaft. A differential travel device characterized in that three types of turns are performed by rotating a rotary steering operation tool from a turn to a brake turn for turning and stopping, and a spin turn for turning in the reverse direction.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an overall view of a combine embodying the present invention. In the figure, reference numeral 11 denotes a crawler of combine 1;
Reference numeral 12 (12R, 12L) denotes a crawler drive shaft, 13 denotes a mowing unit, and 14 denotes a grain tank for storing threshed grains.

FIG. 2 is a connection diagram of a combine differential traveling device (mission) embodying the present invention. In the differential traveling device of the present invention, the power of an engine (not shown) is input to a variable displacement pump 16 of a straight traveling HST (hydrostatic continuously variable transmission) via an input pulley 15, and a parallel traveling HST motor 17 is provided. Drive.

Reference numeral 18 denotes an HST output shaft for straight traveling,
The first transmission gear 19 is fixedly connected to the output side of the ST motor 17.

Reference numeral 20 denotes a transmission shaft disposed downstream of the straight-moving HST output shaft 18. An outer peripheral cylinder 21 is rotatably fitted to the outer periphery of the transmission shaft 20. The high speed gear 23 and the high speed gear 24 are spline-connected. The low-speed gear 22, the medium-speed gear 23, and the high-speed gear 24 rotate integrally, move laterally on the outer peripheral cylinder 21 by a fork member (not shown), and the high-speed gear 24 always meshes with the first transmission gear 19.

A cutting clutch 26 is provided at the right end of the transmission shaft 20.
Is arranged.

A cutting pulley 30 transmits power from the cutting pulley 30 to a cutting section (not shown) via a cutting clutch 26.

Reference numeral 31 denotes a first intermediate shaft, which is disposed downstream of the transmission shaft 20, and has a fifth transmission gear 36 fixedly attached to the center of the second transmission gear 32, the third transmission gear 33, and the fourth transmission gear 34. Second
The transmission gear 32 meshes with the low-speed gear 22, the third transmission gear 33 meshes with the medium-speed gear 23, and the fourth transmission gear 34 meshes with the high-speed gear 24.

Reference numeral 25 denotes a turning HST variable displacement pump, which is connected on the same axis as the first intermediate shaft 31 and drives a turning HST motor 27 provided in parallel.

Reference numeral 28 denotes a turning HST input shaft.
The sixth transmission gear 29 is fixedly connected to the output side of the ST motor 27.

Reference numeral 38 denotes a continuously variable transmission shaft which is disposed downstream of the first intermediate shaft 31 and has a seventh transmission gear 35 which is always meshed with the sixth transmission gear 29 fixed thereto.
41 are provided respectively. Left and right switching clutches 40, 4
1 is fixed to the continuously variable transmission shaft 38, and the driven side is fixed to the switching gears 42 and 43. Left and right switching clutches 40, 4
Engaging teeth 40a and 41a are formed on opposite surfaces of the driving side and the passive side. Switching gears 42, 4
3 rotates integrally with the passive sides of the left and right switching clutches 40, 41 and moves integrally in the axial direction.

Reference numeral 46 denotes a side clutch shaft.
8, a straight-moving gear 47 is fixed at the center, and a left output gear 48 and a right output gear 49 are loosely fitted. The left output gear 48 and the right output gear 49 are formed with engagement teeth 48a and 49a on the surface facing the straight gear 47, and are urged by a spring 39 to engage the left output gear 48 and the right output gear 49 with the straight gear 47. The left and right side clutches are combined.

An eighth transmission gear 50 is fixed to the left output gear 48, and the left output gear 48 and the switching gear 42 always mesh. Then, the left output gear 48 and the eighth transmission gear 50 move integrally in the axial direction. Similarly, the ninth transmission gear 51 is fixed to the right output gear 49, and the right output gear 49 and the switching gear 43 always mesh. Then, the right output gear 49 and the ninth transmission gear 51 move integrally in the axial direction.

Grooves are formed in the eighth transmission gear 50 and the ninth transmission gear 51, and side clutch shift forks 52L and 52R engaged with the grooves are provided. The eighth transmission gear 50 and the tenth transmission gear 53 are always engaged, and the ninth transmission gear 51 and the eleventh transmission gear 54 are always engaged. The tenth transmission gear 53 is fixed to the left crawler drive shaft 12L, and the eleventh transmission gear 54 is fixed to the right crawler drive shaft 12R.

In FIG. 3, the left and right side clutches are "engaged".
FIG. 2 shows a circuit diagram of a hydraulic system to “turn off”. In the hydraulic system, a relief valve 71 is provided in an oil tank 70, a hydraulic pump 72 is connected thereto, and a directional switching solenoid 76 is connected to the hydraulic pump 72.
The direction control switching valve 76 driven by L and 76R is connected. The direction control switching valves 76 are connected to direction control cylinders 77L and 77R for operating the side clutch shift forks 52L and 52R, respectively.

The hydraulic system is configured as described above. During the operation of the engine, a constant amount of oil is supplied to the direction control switching valve 76, and the direction control switching valve 76 is switched to the left or right to change the direction control actuator 77L, 77R is operated to separate the left output gear 48 or the right output gear 49 from the rectilinear gear 47, and the left switching clutch 40 or the right switching clutch 41 is brought into the "on" state.

FIG. 4 is a side view of a round handle which is turned left and right to operate turning. The round handle 55 is attached to the handle 5
5a and a shaft portion 55b.
5c, the operation piece 56 is fixed to the lower end, and the bottom is inserted into the bearing 57a of the rotating plate 57.

FIG. 5 is a plan view of the operating piece 56 and the rotary plate 57. The operating piece 56 has a middle portion formed by a shaft 5 of a round handle 55.
5b, and one side of one end is pressed by a spring 56a to maintain a fixed direction. The rotating plate 57 is rotatably attached to a shaft 57b, and a U-shaped member 57c for inserting an end of the operation piece 56 opposite to the spring 56a is attached to one end of the rotating plate 57, and both ends of the other end are pressed by springs 57d in a certain direction. To maintain. Also, U
On the protrusions on both sides of the operating piece 56 inside the letter-shaped member 57c,
The operation piece position detection switches 55L and 55R are provided.

The rotating plate 57 has, at one end, a rod cable 5 for changing the inclination of the swash plate of the variable displacement pump 25 of the HST for turning.
8 is connected.

The round handle 55 is configured as described above. When the handle portion 55a is rotated in either the left or right direction, the operating piece 56 is rotated about the shaft portion 55b, and the left or right operating piece position is detected. The switches 55L and 55R are pressed to operate the switches. When the handle 55a is further rotated, the U-shaped member 57c is pressed to rotate the rotary plate 57 integrated with the U-shaped member 57c about the shaft 57b, and pushes and pulls the rod cable 58 at the lower end.

When the handle portion 55a is released in a rotated state, the handle portion 55a automatically returns to the original neutral position. That is, the operating piece 56 is attached to the spring 56a, and the rotating plate 57 is attached to the spring 57a.
Then, each of them is urged to return to the neutral position.

The combine differential traveling device embodying the present invention has the above-described configuration, and uses the power of the engine to travel straight through the HS.
T through a variable displacement pump 16 and a straight HST motor 17 to an HST output shaft 18 for straight running.
9 and the high-speed gear 24 are rotated. Then, the low-speed gear 22 and the medium-speed gear 23 rotate integrally with the rotation of the high-speed gear 24, and are switched to low speed, medium speed, or high speed by a shifter fork (not shown), so that the second transmission gear 32 or the third transmission gear 33 or The first intermediate shaft 3 via the fourth transmission gear 34
Rotate 1

The rotation of the first intermediate shaft 31 is controlled by the fifth transmission gear 3.
6 to a linear gear 47 meshing with the fifth transmission gear 36.

On the other hand, the rotation of the first intermediate shaft 31
The transmission is transmitted to the turning HST input shaft 28 via the ST variable displacement pump 25 and the turning HST motor 27, and the continuously variable transmission shaft 38 is rotated via the sixth transmission gear 29 and the seventh transmission gear 35. Thus, the rotation of the first intermediate shaft 31 is
7 and the continuously variable transmission shaft 38, the rotation of the continuously variable transmission shaft 38 is interlocked with the rotation of the linear gear 47.

When the combine travels straight, the right and left output gears 48 and 49 are urged by a spring 39 to the straight travel gear 47.
And at the same time, the left and right switching clutches 40 and 41 are set to the "off" state. Then, the left crawler drive shaft 12L is rotated from the left output gear 48 via the eighth transmission gear 50 and the tenth transmission gear 53, and from the right output gear 49 via the ninth transmission gear 51 and the eleventh transmission gear 54. To rotate the right crawler drive shaft 12R. As a result, the right and left crawlers rotate in the same direction and at the same speed, and the machine body goes straight.

When turning the combine in the left direction, first, the round handle 55 is turned to the left to turn on the operating piece position detection switch 55L. Actuating piece position detection switch 55
When L is turned on, the direction switching solenoid 76L is operated to switch the direction control switching valve 76 to the left, and the direction control cylinder 77L is operated to move the side clutch shift fork 52L to the left. Output gear 48
To separate. Then, after the left crawler has temporarily rotated, the left switching clutch 40 is in the "ON" state, and the right switching clutch 41 is in the "OFF" state. Thus, the rotation of the continuously variable transmission shaft 38 is transmitted to the left output gear 48 via the left switching clutch 40 and the switching gear 42. At this time, the left output gear 48 is separated from the rectilinear gear 47 and the rotation of the left output gear 48 is
0, the left crawler drive shaft 12 via the tenth transmission gear 53
To L.

When the round handle 55 is further turned to the left, the swash plate of the variable displacement pump 25 of the turning HST connected to the rod cable 58 tilts forward, and the turning HST motor 27 rotates forward. The left crawler drive shaft 12L rotates in the same direction as the right crawler drive shaft 12R. At this time, the rotation speed of the left crawler drive shaft 12L is
Since the number of rotations is smaller than the number of rotations of R, the left crawler advances later than the right crawler, resulting in a mild turn in which the aircraft slowly turns left.

The operating torque of the round handle 55 is, as shown in FIG. 6, until the operating piece position detecting switches 55L and 55R are turned on and the left and right side clutches are switched (a in FIG. 6).
The range is small, and when the swash plate of the variable displacement pump 25 is tilted to drive the turning HST motor 27, it is increased to divide the strength into two stages. For this reason, the operating piece 56
The difference between the force of the spring 56a and the force of the spring 57d of the rotating plate 57 (portion "b" in the figure) is provided to reduce the force of the spring 56a.
Set weaker than force. Thus, by turning the round handle 55 lightly at first, the side clutch can be switched to make a delicate change of direction. When the round handle 55 is further turned strongly, the turning HST motor 27 is driven and turned for the first time. For this reason, even if the round handle 55 is operated by mistake, it does not turn suddenly unless force is applied, so that it is safe.

When the round handle 55 is further turned, the rotation speed of the turning HST motor 27 decreases in proportion to the rotation angle and stops at a fixed angle. At this stage, the aircraft transitions to a brake turn that pivots about the left crawler.

When the round handle 55 is further turned, the turning H
The swash plate of the variable displacement pump 25 in ST tilts in the reverse direction, the HST motor 27 for turning rotates in the reverse direction, and the rotation speed increases in proportion to the rotation angle. At this stage, the aircraft transitions to a spin turn in which the left and right crawlers rotate in opposite directions to each other.

Although the leftward turning has been described above, the same applies to the rightward turning.

Next, the variable displacement pump 25 of the turning HST
Alternatively, a description will be given of a differential traveling apparatus in which the initial tilt angle of the swash plate of the turning HST motor 27 is adjusted to enable automatic direction control of the crawler-type work vehicle or the amount of body displacement during turning by manual adjustment.

The automatic directional control outputs a signal when one of the cutting direction sensors attached to the left and right of the weeding rod touches the culm row, and based on this signal, moves the machine body in the direction away from the culm row. By changing to, the known control that the aircraft automatically follows the culm row, but if there is a difference in the initial rotation speed of the left and right crawlers and is not balanced, the aircraft is It becomes easy to poke and automatic direction control does not work properly.

In order to adjust the initial rotation speed, an initial rotation adjusting mechanism 60 as shown in FIG. The initial rotation adjusting mechanism 60 is provided with a lever 6 on a shaft 25a for tilting a swash plate of the variable displacement pump 25.
1 is connected. The other end of the lever 61 is a roller 61a
And a rod cable 58 is connected below the roller 61a.

One end of the arm 62 is connected to the spring 63 to press the lever 61, and the other end is connected to the pin 64 a of the moving frame 64. The moving frame 64 is provided with an adjusting screw 64b and attached to the supporting frame 65 so as to be slidable left and right.

The initial rotation adjusting mechanism 60 is configured as described above, and turns the adjusting screw 64b to slide the arm 62 left and right, and interlocks with the arm 62 to tilt the lever 61 right and left. The lever 61 is pressed by the spring 63 and maintains the state at an arbitrary tilt angle. Thereby, the reference neutral point (initial tilt angle) of the lever 61 can be arbitrarily changed. That is, as shown in FIG. 8, the reference neutral point of the lever 61 is set to N
, The initial rotational speed of the variable displacement pump 25 is changed from r to r ′.

[0044]

According to the differential traveling device of the present invention, the turn operation is performed by a round handle instead of the conventional lever. Therefore, according to the present invention, the turning operation can be performed like a car, and the operating force is smaller than that of the conventional lever, so that the operation of the work vehicle can be easily and easily performed.

[Brief description of the drawings]

FIG. 1 is an overall view of a combine embodying the present invention.

FIG. 2 is a connection diagram of a combine differential traveling device embodying the present invention.

FIG. 3 is a circuit diagram of a hydraulic system for turning on and off a side clutch.

FIG. 4 is a side view of a round handle.

FIG. 5 is a plan view of an operation piece and a rotating plate.

FIG. 6 is a graph showing a relationship between rotation of a round handle and operation torque.

FIG. 7 is a side view of the initial rotation adjusting mechanism.

FIG. 8 is a graph showing a relationship between a tilt angle of a lever and an initial rotation speed of a variable displacement pump.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Combine 11 Crawler 12 Crawler drive shaft 13 Cutting part 14 Grain tank 15 Input pulley 16 HST pump 17 HST motor 18 Straight HST output shaft 19 First transmission gear 20 Transmission shaft 21 Outer cylinder 22 Low speed gear 23 Medium speed gear 24 High speed gear Reference Signs List 25 variable displacement pump 26 cutting clutch 27 turning HST motor 28 turning HST input shaft 29 sixth transmission gear 30 cutting pulley 31 first intermediate shaft 32 second transmission gear 33 third transmission gear 34 fourth transmission gear 35 seventh transmission Gear 36 Fifth transmission gear 38 Continuously variable transmission shaft 39 Spring 40, 41 Switching clutch 42, 43 Switching gear 46 Side clutch shaft 47 Straight running gear 48 Left output gear 49 Right output gear 50 Eighth transmission gear 51 Ninth transmission gear 52 Side Clutch shift fork 53 10th transmission gear 54 Eleventh transmission gear 55 Round handle 56 Working piece 57 Rotating plate 58 Rod cable 60 Initial rotation adjusting mechanism 61 Lever 62 Arm 63 Spring 64 Moving frame 65 Support frame 70 Oil tank 71 Relief valve 72 Hydraulic pump 76 Direction control switching valve 77 Direction Control cylinder

Claims (1)

[Claims] 1. A crawler-type work vehicle having a mission for independently transmitting the output of an engine to left and right crawlers of a machine body. A continuously variable transmission shaft for continuously changing and transmitting speed from rotation to reverse rotation, a pair of left and right side clutches for disconnecting one of the left and right crawlers from the straight traveling shaft and connecting to the continuously variable transmission shaft, and rotary steering Side clutch switching means for rotating the operation tool to switch the side clutch, and continuously variable transmission shaft control means for rotating the rotary steering operation tool to control the rotation speed and direction of the continuously variable transmission shaft; A milder that turns the left and right crawlers with the outside in the turning direction connected to the straight-moving shaft and the inside in the turning direction with the continuously variable transmission shaft, and then rotates the continuously variable transmission shaft at low-speed forward rotation. A rotary steering operation tool that performs three types of turns, from a stop to a brake turn to turn and a reverse turn to a spin turn.