JPH0130967Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is a working machine control system for agricultural tractors that has a configuration that enables control of both the position control device and the depth control device. This allows the feedback signal to be connected or disconnected.

The depth control device controls the position of the rotary tiller's tiller claw tip and rear cover to always remain constant, and has the effect of keeping the tilling depth constant even if the field is uneven and the tractor is tilted. It is.

In such a depth control device,
Without removing the feedback wire connected from the rear cover to the depth control arm, a structure similar to that of simply increasing the length of the inner wire can be created to prevent the vertical movement of the rear cover from reaching the depth control arm. This is what I did.

In conventional technology, as in the technology described in Japanese Unexamined Patent Publication No. 51-141207, it was possible to connect and disconnect the feedback signal by removing an insertion pin between the end of the feedback wire and the link. .

This invention changes the inner wire fixed link placed between the depth control arm fixed to the feedback shaft on the hydraulic case side and the feedback wire to a fixed/rotatable state, so that the inner wire fixed link can be fixed and rotated. This allows the operator to easily connect/disconnect the signal from the feedback wire while continuing tillage work.

The purpose of the present invention is as described above, and the structure of the present invention will be explained based on the structure of the embodiment shown in the attached drawings.

FIG. 1 is a plan view of a hydraulic system for lifting and lowering a working machine of an agricultural tractor, FIG. 2 is a side view, and FIG. 3 is a front sectional view.

The hydraulic system is mainly composed of a hydraulic case 1, and a piston is slidably fitted into a hydraulic cylinder 31 in the hydraulic case 1, and the piston is moved back and forth by pressure oil to connect a connecting rod 44, an arm 43,
The lift arm 3 is rotated up and down via the lift arm shaft 32. 28 is a safety valve, 30
is a relief valve.

A hydraulic valve case 2 is provided on the side of the hydraulic case 1, and a hydraulic valve device (not shown) is fixedly attached to the side of the hydraulic case 1. Attach the front end of the hydraulic cylinder to cylinder head 1.
9, and a hydraulic lock lever 17 and a slow return lever 33 are provided on the cylinder head.

The spool of the hydraulic valve arranged in the hydraulic valve case 2 protrudes forward, and the spool operating rod 24
It is configured to come into contact with the rear surface of the.

The spool operating rod 24 is moved back and forth by both the upper and lower pins 26 and the lower pin 27, and the combined amount of movement pushes the spool.

The pin 26 is linked to a hydraulic lever shaft 25 via a crank portion 25a, and when the operator operates the hydraulic lever 14, the upper part of the spool operating rod 24 is moved back and forth. On the other hand, the pin 27 is fixed to the outer periphery of the cylinder 29 in the shape of a crank, and is connected via the feedback shaft 23 and the fixed cylinder 22a.
It is linked to the depth control arm 22 and the feedback arm 7.

An inner wire fixing link 9 and a release spring 20 are connected to the depth control arm 22.

As shown in FIGS. 4 and 5, a notch hole 22d is provided at the tip of the depth control arm 22, so that the inner end of the release coupling pin 9a of the inner wire fixing link 9 of the feedback wire 42 can be inserted from the outside. are doing.

In addition, in order to insert the release coupling pin 9a into the notch hole 22d, the release spring 20 fixed inside the depth control arm 22 is inserted into the release spring 20 shown in FIG.
0', then insert it. After fitting, return the release spring to its original position, insert the release/coupling pin 9a into the hole 20b, and make sure that the release/coupling pin 9a comes out from the notch hole 22d. It is locked to prevent it from happening. Through this operation, the depth control arm 22 and the inner wire fixing link 9 are integrated, and the movement of the feedback wire 42 is transmitted to the depth control arm 22 and then to the spool operating rod 24 via the feedback shaft 23.

The tip of the feedback wire 42 is connected to the rear cover of the rotary tiller, and the tillage depth is sensed by the up-and-down movement of the rear cover to provide feedback.

One end of the inner wire fixed link 9 is connected to a pivot shaft 22 fixed to the depth control arm 22.
c, and the end of the inner wire is pivotally connected to the outside of the release/connection pin 9a at the other end. Also, there is a screw hole 22 in the center of the depth control arm 22.
b, 22b are drilled, and this screw hole 22b
A release spring 20 is fixed to the holder with screws 21, 21. The distal end of the release spring 20 protrudes beyond the distal end of the depth control arm 22 and forms a curved portion so that it can be easily operated with a fingertip.

A feedback link 6 is connected to the tip of another feedback arm 7 fixed on one feedback shaft 23. An operating spring 18 is interposed on the feedback link 6 via a spring receiver 39, and the operating spring 18 is constructed of a double spring.

The feedback link transmits the movement of the lift arm 3 to the feedback shaft 23, and instead of directly transmitting the movement of the lift arm 3 through the bracket 4 and the switching arm 5, it connects the operating spring 18 with the spring receiver 36. The configuration is such that when pressed, the pressure is transmitted elastically to the feedback shaft 23 and the spool operating rod 24. The presence of the operation spring 18 eliminates the double engagement with the movement of the feedback arm 22, and also smoothes the convergence of hunting operations during depth control and position control.

As mentioned above, since the operating spring 18 is provided in the direction in which the feedback wire 42 is tensioned, the structure is such that the wire does not become tensioned.

Further, since the wire is not cut in the direction of loosening of the Bowden wire, a collar 40 and an adjustment screw 41 are provided at the rear of the spring receiver 24, and no spring is provided.

The switching arm 5 is configured to be switchable by a switching lever 8 in order to change the operating position of the feedback link 6 with respect to the bracket 4 in the case of depth control and position control. Bracket 4 of feedback link 6
The point of action is the pivot hole 5c of the spring receiver 36 of the switching arm 5, and by converting the distances L1 and L2 from the center of the lift arm shaft 32 up to this point into position control and depth control. , the amount of rotation is adjusted.

This switching is performed by switching the switching arm 5 to position 5', and the upper end of the switching lever 8 is connected to the position control recess 10b and the depth control recess 10d of the switching lever guide 10.
This is done by moving the In order to prevent the switching lever 8 from being operated unnecessarily, a malfunction prevention plate 11 is provided and fixed to the switching lever guide 10 with butterfly bolts 12. The malfunction prevention plate 11 has a pin 11a at one end pivoted to a pin hole 10d of the switching lever guide 10, and a hole 11b at the tip.
overlaps with the hole 10c of the switching lever guide 10 and fixes with the butterfly bolt 12, the position control recess 10b and the depth control recess 10 are formed.
The grooves are configured so that all but d are closed.

The switching lever guide 10 is fixed at a base 10a to a bracket 4 that rotates together with the lift arm shaft.
It rotates together with the lift arm 2.

11 and 12 in the pivot hole 4a of the bracket 4.
The pivot pin 5a of the switching arm 5 shown in the figure is loosely fitted, and the switching arm 5 is configured to be movable up and down. It is fixed to the lift arm shaft 32 through the hole 4b of the bracket 4. A base portion of a switching lever 8 is fixed to the holes 5b, 5b of the switching arm 5. Also, a spring receiver 36 is provided in the pivot hole 5c at the other end of the switching arm 5.
The pivot shaft 36a is inserted.

When using the depth control arm 9 as a position control device, the depth control arm 9 is released by the release spring 20 so that it can be rotated freely as indicated by 9', so that the movement of the rear cover is not transmitted to the feedback shaft 23, and the depth control arm 9 is By moving the switching lever 8 between depth control and depth control to the position control side and placing the hydraulic lever 14 in the desired position within the hydraulic lever guide 16, the lift arm and the work equipment will automatically stop at a fixed position. .

Since the hydraulic lever moves widely from the set position to the raised and lowered positions in order to raise and lower the work equipment at the edge of the field, it is necessary to set the hydraulic lever so that it can be easily stopped at a fixed position using the setting device 35 shown in Fig. 1. You can also do it.

Conversely, when used in a depth control device, the inner wire fixed link 9 and the depth control link 22 are integrated with the release spring 20, and the feedback shaft 23 is rotated by the movement of the Bowden wire 42, and the switching lever In step 8, the point of action of the feedback link on the bracket 4 is changed, the movement of the lift arm is also fed back to the feedback arm 7, and the position of the lift arm is adjusted so that the distance between the tilling claw and the rear cover is always at the predetermined tilling depth. control.

The desired plowing depth is changed using the tailwheel adjustment handle, and the hydraulic lever 14 is placed at a fixed position during depth control, and is operated only when moving the work machine up and down when turning at the edge of the field.

The hydraulic lever 14 is connected to a hydraulic lever shaft 25 by a mounting bracket 15, and the hydraulic lever guide 1
6 is fixed to the hydraulic case 1 by a mounting plate 38.

As described above, the present invention has a structure in which both ends of the spool operating rod 24 that contact the spool end of the hydraulic valve device are operated by the hydraulic lever 14 and the depth control arm 22, and the depth control arm 22 has a cutout hole at the tip thereof. constitutes 22d,
A long hole at one end of the inner wire fixing link 9 is pivotally supported in the middle by a pivot shaft 22c, a feedback wire 42 is connected to the other end of the inner wire fixing link 9, and the inner wire is connected to the notch hole 22d. The release coupling pin 9a of the fixed link 9 is inserted into the depth control arm 22 within the range of the elongated hole.
It can be inserted by sliding it along the
A cutout hole 2 is inserted into the hole 20b of the release spring 20 fixed to the other side of the depth control arm
Since the release coupling pin 9a fitted into the opening 2d can be inserted and locked, the following effects can be achieved.

First, stop the depth control state and
When changing to position control, it is necessary to cut off the feedback path that transmits the vertical movement of the rear cover to the depth control arm 22, but conventionally a pine needle pin was inserted and removed between the rear cover and the end of the feedback wire. He was going by doing this.

Therefore, when an operator rides on a tractor and switches between depth control and position control while plowing, it is necessary for the operator to get off the seat, insert and remove the pine needle pin, and stop the feedback wire function each time. be.

In the present invention, the depth control arm 22 provided on the side of the hydraulic case and the inner wire fixing link 9 pivoted thereon by a pivot shaft 22c are disconnected by being removed at the release engagement pin 9a. As a result, the operator does not have to get off the seat, and can now switch gears without getting off the vehicle even during tilling work.

Second, while the depth control arm 22 and the inner wire fixing link 9 are integrated at the release coupling pin 9a, the inner wire is inserted into the hole 20a of the release spring 20 into the release coupling pin 9a. This makes it possible to lock the fixed link 9 from coming off.

Thirdly, in order to obtain free movement of the feedback wire 42, instead of inserting and removing the pin, the release coupling pin 9a remains attached and the inner wire remains attached to the inner wire fixing link 9.
It can be removed, so if you want to reconnect it,
The release coupling pin 9 allows for easy alignment of pin holes.
There is no loss of a.

[Brief explanation of the drawing]

Fig. 1 is a plan view of the hydraulic system for raising and lowering the working machine of an agricultural tractor, Fig. 2 is a side view, Fig. 3 is a front sectional view, Fig. 4 is a front sectional view of the depth control arm 22, and Fig. 5 is a front sectional view of the depth control arm 22. 6 is a plan view of the switching lever guide 10, FIG. 7 is a side view of the bracket and the switching lever guide,
Figure 8 is the same front view, and Figure 9 is the malfunction prevention plate 1.
1 is a side sectional view of No. 1, and FIG. 10 is a plan view of No.
1 is a side view of the switching arm 5, FIG. 12 is a sectional view taken along line AA in FIG. 11, and FIG. 13 is a sectional view taken along line BB in FIG. 6...Feedback link, 7...Feedback arm, 8...Switching lever, 9...Inner wire fixing link, 9a...Release coupling pin,
20... Release spring, 20b... Hole, 22... Depth control arm, 22c... Pivot shaft, 2
2d...Notch hole, 23...Feedback shaft, 2
4...Spool operating rod, 27...pin, 42...
Feedback choir.

Claims (1)

[Scope of utility model registration request] In a configuration in which both ends of the spool operating rod 24 that contact the spool end of the hydraulic valve device are operated by the hydraulic lever 14 and the depth control arm 22, a cutout hole 22d is formed at the tip of the depth control arm 22, and a cutout hole 22d is formed at the tip of the depth control arm 22. The pivot shaft 22c
supports the elongated hole at one end of the inner wire fixing link 9, and connects the feedback wire 42 to the other end of the inner wire fixing link 9.
The release coupling pin 9a of the inner wire fixing link 9 can be inserted into the notch hole 22d by sliding it along the depth control arm 22 within the range of the elongated hole, and is fixed to the other side of the depth control arm 22. Release spring 2
A working machine control device for an agricultural tractor, characterized in that a release coupling pin 9a inserted into a notch hole 22d can be inserted into the hole 20b of the cutout hole 20b and locked.