JPS6026568Y2 - Position control device for tractors - Google Patents

Description

[Detailed description of the invention] This invention has a working device installed between the left and right front wheels and the left and right rear wheels at a height that is set based on the operation position of the control lever installed in the control section at the rear of the aircraft. To automatically raise and lower
A hydraulic cylinder for lifting and lowering the working equipment and a feedback link for returning the control valve of this cylinder to neutral are placed on the sides of the transmission case, which is arranged in the middle of the left and right sides of the front and rear wheels, facing in the front-rear direction. This invention relates to a position control device for an installed tractor.

If the hydraulic cylinder and feedback link are installed on the sides of the transmission case, compared to installing them at the bottom or top of the transmission case, for example, there is an advantage that muddy water can be avoided as much as possible, and various parts protruding from the top of the transmission case can be avoided. Although there is an advantage that interference with the lever can be avoided, there is a risk that the working device or other working device connecting tools may come into contact with the hydraulic cylinder or the feedback link when the working device is attached or detached.

Hydraulic cylinders generally have fairly high strength in order to withstand large loads, so they will not be easily deformed or damaged even if some other object comes into contact with them, but feedback links are normally subject to large forces acting on them. Since it is not a member that is used to protect the body and does not have particularly high strength, it is relatively easy to deform and damage if a large external force is applied from the side due to contact with another object, and position control after such an accident occurs. This made it impossible to carry out operations properly.

The present invention is an attempt to solve the above-mentioned problem through a simple improvement, and in the position control device for a tractor having the above-mentioned structure, the feedback link is placed inward of the machine body relative to the hydraulic cylinder, and is placed on the side. It is characterized in that it is disposed in a state that it substantially overlaps with the hydraulic cylinder when viewed.

Therefore, since the hydraulic cylinder, which is stronger than the feedback link, can prevent other objects from coming into contact with the feedback link as much as possible, the above-mentioned problems can be solved and the system can be maintained in good condition for a long period of time. It became possible to perform position control.

The implementation of the present invention will be described below with reference to illustrative drawings.

FIG. 1 shows the plane of an offset type tractor.
A pair of left and right front wheels 1a, lb; a pair of left and right rear wheels 2a, 2b
In addition, an engine 3 and a transmission case 4 for traveling that is long in the longitudinal direction are arranged in parallel in the longitudinal direction at a location offset to the left of the left and right wheels, and a location offset to the right between the left and right rear wheels 2a and 2b. A pilot seat 5 is installed in the vehicle.

The left and right front wheels 1a, lb are configured as steering wheels whose direction can be changed by a rotating bundle 6 provided in the front of the seat 5.

The left and right rear wheels 2a, 2b are configured to be pivotally supported by the rear end of the transmission case 4 and driven by an output from inside the transmission case.

An intermediate location in the longitudinal direction of the aircraft, that is, the left and right front wheels la, l
b and the left and right rear wheels 2at 2b, there is a cultiform 7...
is equipped.

This cultivar 7... is configured to be automatically raised and lowered to a height set based on the swing operation position of a control lever 8 provided on the left side of the seat by a position control device described below. .

namely, a pair of lift arms ``lla'' connected to the culvert 7 via a link mechanism 10 at both ends of a horizontal shaft 9 pivotally supported at the upper front part of the mission case 4;
llb is fixed, and these lift arms lla, llb
The lift arm 11a on the left side is pivotally connected to the front end of a hydraulic cylinder 12 installed on the left lateral side of the mission case 4 facing in the front-rear direction, and the rear end of the hydraulic cylinder 12 is connected to the mission case 4. 4 is pivotally connected.

A lever support shaft 13 is located above the unloading force of the mission case 4.
is suspended horizontally, and a swing arm 14 is attached to the left end of this support shaft 13.
is fixed, and the upper end of the rod operating arm 16 pivotally supported by the operating rod 15a of the control valve 15 of the hydraulic cylinder 12 is connected to the swinging arm 14 via a link 17.
It is linked and linked.

The lower end of the rod operating arm 16 is connected to the upper end of a feedback arm 18 that swings around a fixed fulcrum 1 and a link 19.
The hydraulic cylinder 1
Feedback link 20 with one end pivoted to the front end of 2
The other end is operatively connected to the lower end of the feedback arm 18.

The feedback link 20 is connected to the hydraulic cylinder 1
As shown by the dotted line in FIG. 3, the feedback link 20 is disposed at a location on the inside of the fuselage body, substantially overlapping with the hydraulic cylinder 12 when viewed from the side, and this feedback link 20 itself is
It is composed of a rod-shaped member equipped with a turnbuckle mechanism 20a, and is configured so that its length can be changed and adjusted.

The operation will be explained below. When the lever 8 is swung back and forth to swing the swing arm 14, the rod operating arm 16 swings about the fulcrum Q1 at its lower end and pushes the rod 15a. A pulling operation is performed, and the cultivar 7... is raised and lowered by this.

When the feedback link 20 moves back and forth as the cylinder 12 expands and contracts, the rod operating arm 16 swings about the fulcrum Q4 at its upper end, causing the rod 1
5a is pushed and pulled to the neutral position, and as a result, the cultivar 7... is automatically raised and lowered to a height set based on the operating position of the lever 8.

The operating lever 8 is engaged with and supported by a rotating member 21 rotatably supported on the support shaft 13 so that it can move only laterally, and is shifted to the right in FIG. Then, the first engaging rod 28a of the first member 22 fixed to the support shaft 13 is engaged to perform position control in the embodiment.

When shifted to the left in FIG. 4, another second engagement rod 23b is engaged with the second member 24 rotatably supported on the support shaft 13, and the second member 24 is used The operator then operates a position control device (not shown) for the cultivar 25 connected to the rear of the fuselage.

Furthermore, when it is shifted to the left and right center position, the first and second members 22 and 24 are operated simultaneously to move the cultimeter 7 and the middle part of the fuselage.
- and the rear cultivar 25 - are raised and lowered at the same time.

It has become.

In addition, it is arranged in parallel on the side part of the lever 8. The lever 26 is a draft that automatically raises and lowers the working device according to the traction force detection result in order to stabilize the plowing depth used when a ground working device such as a plow is attached in place of the rear cultivator 25. It is connected to a control device and sets the traction force.

[Brief explanation of the drawing]

The drawings show an embodiment of the position control device for a tractor according to the present invention, and FIG. 1 is an overall side view, and FIG.
The figure is a schematic side view, FIG. 3 is a side view of the position control device, and FIG. 4 is a longitudinal sectional view of the lever mounting portion. la, lb...front wheel, 2a*2b...
Rear wheel, 7... Working device, End... Operating lever, 12... Hydraulic cylinder, 15...
Control valve, 20...Feedback link.

Claims (1)

[Scope of utility model registration request] A working device 7 placed between the left and right front wheels 1a, lb and the left and right rear wheels 2a, 2b is automatically raised and lowered to a height set based on the operating position of a control lever 8 provided in a control section at the rear of the aircraft body. A transmission case 4 is provided with a hydraulic cylinder 12 for lifting and lowering the work equipment and a feedback link 20 for returning the control valve 15 of this cylinder 12 to neutral position, which is disposed in the left-right intermediate position of the front and rear wheels 1a, 2a, etc., facing in the front-rear direction.
This is a position control device for a tractor installed in the longitudinal direction on the lateral side of a tractor, and the feedback link 20 is installed at a position inward of the vehicle body than the hydraulic cylinder 12 when viewed from the side.
1. A position control device for a tractor, characterized in that the device is arranged so as to substantially overlap the position control device.