JPS6129207Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a hydraulic system for a tractor.

It is well known that in the case of a tractor equipped with a three-point link, various types of work equipment are connected by the three-point link, and hydraulic pressure is applied to the three-point link so that the various types of work equipment can be raised and lowered. .

A conventional hydraulic system for a tractor is equipped with a single-acting or double-acting hydraulic system on the vehicle body, that is, a hydraulic system consisting of a cylinder tube, a piston that fits into the cylinder tube, etc., and a pair of left and right lift arms that interlock with the piston. Usually, each lift arm is connected to the middle of the left and right lower links by a lift rod, and the housing that supports the cylinder tube, the lift arm, and the lift rod are considered to be essential components or members, and the number of parts is reduced. As a result, the cost has increased and the weight has become excessive.

Furthermore, in the case of work machines equipped with automatic leveling means, for example, so-called horizontal rotary machines, the level sensor and lifting lever are provided separately, so that the advantages of the horizontal rotary machine may not be fully utilized.
When attaching and detaching the work equipment to the three-point link, if one side of the lift rod is of the so-called screw type or hydraulic cylinder type, it becomes extremely difficult to align the mounting hole at the rear of the lower link with the mounting hole of the work equipment. It was.

The present invention was devised in view of the above-mentioned circumstances, and by connecting the left and right lower links and the tractor side with a hydraulic cylinder body that can be expanded and contracted independently and in conjunction with each other, the lift arm, lift rod, and housing can be improved. etc., thereby achieving a significant cost reduction, and also facilitating tilt control and attachment/detachment of the tractor and working equipment.Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

In FIGS. 1 to 3, a tractor T has a wheel shape as an example, and 1 is a vehicle body, 2 is a rear wheel, and 3 is a seat. The PTO shaft 4 is enabled for transmission.

One end of each link of the three-point link L is removably pivoted to the tractor T via a ball joint and a pin, and in this example, a support stand 5 provided at the center of the upper part of the vehicle body 1 is used.
An extension stand 6 is detachably provided at the extension stand 6, one end of a turnbuckle-shaped top link 7 is pivotally connected to the extended end of the extension stand 6, and one end of each of left and right lower links 8R, 8L is attached to the lower part of both sides of the vehicle body 1. It consists of a pivot point.

The other end of each link 7, 8R, 8L of the three-point link L removably pivots the work machine R via a ball joint, pin, etc. In this example, a horizontal rotary is illustrated as the work machine R. The PTO shaft 4 and the power receiving shaft are interlocked and connected by an interlocking shaft 9 with a universal joint.

The middle of the left and right lower links 8R and 8L in the longitudinal direction and the tractor T side are each telescopic hydraulic cylinder bodies 1.
In this embodiment, the base 11 is firmly fixed on the vehicle body 1 with bolts 12, etc., and support arms 13R, 13 are connected to both ends of the base 11.
One end of each cylinder body 10R, 10L is connected to each arm 13R, 13L by a universal joint 14.
Each cylinder body 1 is removably supported by R and 14L.
The other ends of 0R and 10L are removably pivoted to lower links 8R and 8L via universal joints 15R and 15L.

In this example, the hydraulic cylinder bodies 10R and 10L have their tubes pivotally supported on the tractor side and the piston rams on the lower link side, but this may be reversed, and the hydraulic cylinder bodies 10R and 10L are supported simply. Of course, it may be either a moving type or a double acting type, and by providing the base 11 at the rear of the seat 3, the base 11 can be used as a mounting base for the driver's guard, that is, a head guard, a sunshade, a safety frame, etc.
1 and bolt 12 can be used in common.

The telescoping hydraulic cylinder bodies 10R, 10L can be controlled by moving left and right independently and by moving left and right, and furthermore, the control can be performed automatically or in combination with control using a manual lever.

That is, 16 is a control body, which can be controlled by a signal from a manual lever 17 or a horizontal rotary level sensor 18, and can control individual control bodies 19R and 19L such as solenoid valves independently and in conjunction with each other. 19R, 19L is supplied with hydraulic pressure via a pump P activated by an engine, etc., to hydraulic cylinders 10R, 19L through piping members 20R, 20L.
It is possible to send and return liquid to 10L.

In the above embodiment, when connecting the work machine R, the manual lever 17 is used to control the control bodies 19R and 19L.
By extending and contracting the hydraulic cylinder bodies 10R and 10L individually through the It is extremely convenient to align the holes with the work machine R.
This makes it easy to attach and detach.

When working on flat land, use tractor T and work equipment R.
There is no need to consider relative position changes in the left-right direction (level plane) of the left and right hydraulic cylinder bodies 10.
The work is carried out with the lengths R and 10L constant, and by moving the manual operation lever 17 back and forth from the seat 3, for example, the control body 16 allows interlocking control with the control bodies 19R and 19L. The working machine R can be raised and lowered relative to the tractor T by expanding and contracting the cylinder bodies 10R and 10L by the same length.

Also, when working on slopes, tractor T and work equipment R
is shifted relative to the level plane as shown in FIG. 3, and it is desired to make the working depth uniform. . During such work, when a degree of inclination occurs, the hydraulic cylinder bodies 10R and 10L can be independently expanded and contracted by the signal from the electric sensor 18 via the control bodies 16 and 19R and 19L, thereby enabling automatic control. In addition, when lifting the work equipment R during work on a slope, the hydraulic cylinder bodies 10R, 10 are operated by the manual operation lever 17.
L is linked (synchronized) and shortened. In addition,
At this time, when the lifting amount reaches the limit, it is desirable to make the hydraulic cylinder bodies 10R and 10L the same length to prevent noise due to uneven joint angles even if the cylinders are lifted further.

The present invention provides a tractor T equipped with a three-point link L for connecting a working machine, in which a pair of left and right support arms 13R and 13L are fixedly attached to the tractor T and project upward from the tractor T.
These support arms 13R, 13L and the left and right lower links 8R, 8L of the three-point link L are connected to a pair of left and right telescopic hydraulic cylinder bodies 10 for lifting and lowering the work machine.
This hydraulic system for a tractor is characterized in that it is provided with a control body 16 which is connected by R and 10L and expands and contracts the cylinder bodies 10R and 10L independently and in conjunction with each other, so that it has the following advantages. be.

Since the telescoping hydraulic cylinder bodies 10R and 10L have the functions of conventional lift arms and lift rods, the number of parts can be significantly reduced, resulting in significant cost reductions and light weight, which is advantageous for wet field performance. becomes.

Further, since the telescoping hydraulic cylinder bodies 10R and 10L are conventional internal hydraulic cylinders and pistons, and are in an external form, maintenance is also advantageous.

Furthermore, since the telescopic hydraulic cylinder bodies 10R and 10L can be independently and interlocked, the relative inclination of the tractor T and the work equipment R can be easily adjusted. can also be automatically controlled, improving work accuracy and making it easier to attach and detach the work machine R.

[Brief explanation of the drawing]

FIG. 1 is a side view of an example of the present invention shown in a state where it is attached to a working machine, FIG. 2 is a plan view showing an overall outline of the present invention, and FIG. 1 is an explanatory rear view of FIG. 1. T...Tractor, L...Three-point link, 1...Vehicle body, 7...Top link, 8R, 8L...Lower link, 10R, 10L...Telescopic hydraulic cylinder body, 16...Control body, 17... ...Manual operation lever.

Claims (1)

[Scope of Claim for Utility Model Registration] In a tractor T equipped with a three-point link L for connecting a working machine, a pair of left and right support arms 13R and 13L that protrude upward from the tractor T are fixed to the tractor T,
These support arms 13R, 13L and the left and right lower links 8R, 8L of the three-point link L are connected to a pair of left and right telescopic hydraulic cylinder bodies 10 for lifting and lowering the work machine.
A hydraulic system for a tractor, characterized in that a control body 16 is provided which is connected by R and 10L and expands and contracts the cylinder bodies 10R and 10L independently and in conjunction with each other.