JPH07327404A - Work machine control device of tractor for agriculture - Google Patents

Abstract

PURPOSE:To obtain a work machine-controlling device of a tractor for agriculture, capable of easily attaching a position control lever, a tilling depth- controlling lever and an electromagnetic valve for horizontal control in a narrow space and capable of protecting the electromagnetic valve for horizontal control. CONSTITUTION:In the work machine-controlling device of a tractor for agriculture, a longitudinally L-shaped bracket 17 is attached to one side of a hydraulic housing 1 supporting a position control lever and a tilling depth control lever, and a stoppage-inhibiting member for inhibiting the stoppages of the lever and the lever is disposed in the vertical part along the side surface of the hydraulic housing 1 of the bracket 17. A horizontal control electromagnetic valve disposed in the oil passage of a horizontal control cylinder is attached to the lower surface of the horizontal part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work machine control device for an agricultural tractor which controls a work machine connected to the rear portion of a machine body so as to be able to move up and down and horizontally.

[0002]

2. Description of the Related Art Conventionally, a working machine is mounted at a rear portion of a machine body so that the working machine can be moved up and down, and the working machine is controlled to move vertically and horizontally by a hydraulic system. The control valve is operated by the manual operation means,
Also, a work machine control device for an agricultural tractor, which is operated according to the detection result of the work machine height detector and operates the horizontal control electromagnetic valve of the horizontal control cylinder according to the detection result of the horizontal detector, is already known.

[0003]

In the known working machine control device for agricultural tractors, the manual operation means is mounted on the hydraulic housing via one bracket, and the horizontal control electromagnetic valve is installed in a narrow space. Since it is mounted by a separate bracket, the mounting structure becomes complicated and the assembling work is difficult, and there is a problem in that the horizontal control electromagnetic valve is exposed to rainwater or the like and malfunctions.

[0004]

According to the present invention, a working machine is movably connected to a rear portion of a machine body by a top link and left and right lower links, and is operated by a lifting hydraulic cylinder 6 installed in a hydraulic housing 1. The left and right lift arms 3 are connected to a lower link via a lift rod 3a, and the lifting control valve 10 of the hydraulic cylinder 6 is operated by a manual operation means and a working machine height detector. In the agricultural tractor having the horizontal control cylinder 4 which operates according to the detection result of the horizontal detector, the position control lever 1 serving as the manual operation means is provided.
5 and one side of the hydraulic housing 1 supporting the working depth control lever 16 and having an L-shape when viewed from the front-rear direction.
7 is provided, a retaining portion for preventing the lever 15 and the lever 16 from retaining is provided in a vertical portion of the bracket 17 along the side surface of the hydraulic housing 1, and the horizontal control cylinder 4 is provided on the lower surface of the horizontal portion. The above-mentioned problems are solved by mounting the horizontal control electromagnetic valve 17a interposed in the oil passage.

[0005]

When the position control lever, which is the manual operation means, is operated, the control valve operates to raise and lower the working machine, and when the position control lever is set to the lowest position and the working depth control lever is set to the desired position, During the work, the control valve operates according to the detection result of the detector, so that the ground height of the working machine is automatically controlled to the set position. Further, the horizontal control electromagnetic valve is actuated by the detection result of the horizontal detector installed on the machine body of the work machine or the tractor, and the horizontal control cylinder is thereby expanded and contracted, so that the work machine is always kept in the horizontal posture. The position control lever and the working depth control lever are retained and retained in the vertical portion of the bracket mounted on the side surface of the hydraulic housing, and the horizontal control solenoid valve uses the lower surface of the horizontal portion of the bracket. The bracket is L-shaped so that sufficient strength can be obtained as a whole, and the horizontal portion prevents rainwater from splashing on the horizontal control electromagnetic valve. Moreover, it can protect against obstacles.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An agricultural tractor according to an embodiment of the present invention will be described. A hydraulic housing 1 of a hydraulic device is mounted on a mission case A at the rear of the machine body, and a rotary tiller is provided at the rear of the mission case A. B is connected to a top link and left and right lower links so as to be able to move up and down, and a lift shaft 2 supported on a rear portion of the hydraulic housing 1.
Lift arms 3 mounted on both sides of the
The lift link 3a is connected to a middle part of the lower link via a and 3a, a double-acting horizontal control cylinder 4 is mounted on one lift rod 3a, and a base is spline-fitted to an intermediate part of the lift shaft 2. The tip of the power arm 5 is connected to the piston 7 of the lifting hydraulic cylinder 6 via the piston rod 8.

A lift control valve 10 provided in an oil passage communicating with the hydraulic cylinder 6 is mounted in the center of the lower surface of the hydraulic housing 1, and a link base 11 is connected to a spool 10a protruding rearward from the lift control valve 10. The link base 11 is provided with a return spring 12 whose rear portion is locked by a plate-shaped holder 14, and an L-shaped bracket 17 is screwed to the right side of the hydraulic housing 1 when viewed from the rear. Yes, the support shafts 15a, 16a of the position control lever 15 for controlling the lifting and lowering of the working machine and the plowing depth control lever 16 for setting the tillage during automatic control are provided on the side wall of the hydraulic housing 1 as shown in FIGS. The O-ring is inserted in the hole so as to be oil-tight, and is prevented from being stopped by the fool holes 17f and 17f formed in the bracket 17. Then, the bosses of the levers 15 and 16 are fitted into the small diameter portions of the support shafts 15a and 16a protruding outward, and the friction plates 18 and 18 are provided between the bosses and the bracket 17.
The disc springs 19 and 19 are superposed on the outside and tightened with bolts so that the levers 15 and 16 are braked and held at a desired set position. An electromagnetic valve 17a for control and a valve block 17b are attached, and the valve block 17b is lifted and lowered by being drilled in the hydraulic housing 1 by a sturdy metal return pipe 17c which is laterally extended and bent downward. Since it is connected to the oil port communicating with the control valve 10, it can be firmly held, and the support of the bracket 17 can be reinforced.

Further, a lower portion of the sensor lever 21 is attached to an outer end of the support shaft 20 which is inserted into the left side of the hydraulic housing 1, and a sensor arm 24 is attached to an inner end thereof, which are erected on the left side of the rear portion of the hydraulic housing 1. A support plate 22 is pivotally supported on an upper portion of a downwardly expanding bending link 23, and a front lower end thereof and a pin 21a on an upper portion of the sensor lever 21 are connected to a rod 25.
The lower end of the rear part of the bending link 23 is
Since it is connected via a wire to a working depth detection arm that is a work machine height detector attached to the rear cover of the tiller, the ground cover of the tiller fluctuates (the working depth fluctuates) and the rear cover rotates. When it moves, move it to the sensor lever 2
Propagate to 1.

Further, on the rear part of the link base 11,
The middle portion of the lift control link 27 and the middle portion of the position link 28 are arranged on the lower surface so that these three members are supported by the fulcrum pin 30.
The lift control link 27 has a right side shorter than a predetermined length, and a plate is welded to the upper surface of the end portion thereof to extend the predetermined length to form the upward step 27a. On the left side of 28, a downward step 28a is formed by making the plate shorter than a predetermined length and welding a plate having a large vertical thickness to the lower surface of the end to extend the plate to a predetermined length.
The arm 31 fixed to the inner end of the support shaft 15a of the position control lever 15 is linked via a link 32 to the upper part of the position arm 33 loosely fitted to the support shaft 16a. The lower part of the arm 33 is in contact with the right rear surface of the position link 28.

A control arm 36 fixed to the inner end of the support shaft 16a of the plowing depth control lever 16 is hung below the upward step 27a, and a lateral pin 34 is fixed to the lower portion thereof. Is brought into contact with a vertical receiving pin 35 fixed to the rear surface of the upward stepped portion 27a, and the sensor arm 24 fixed to the inner end of the support shaft 20 of the sensor lever 21 and hung down is A lateral pin 38 fixed to the lower end of the stepped portion 28a is brought into contact with a vertical receiving pin 39 fixed to the left rear surface of the elevating control link 27.

Further, the middle bent portion of the feedback link 40 is fitted to the support shaft 20, the lower end portion of the feedback link 40 contacts the rear surface of the downward step 28a, and the rear portion is Since the upper end is interlocked with the lower end of the link 41 which is connected to the rear of the boss of the power arm 5, the hydraulic cylinder 6 operates and the power arm 5 rotates. The link 40 moves the downward step 28a of the position link 28 back and forth.

Further, a pin-shaped restricting tool 44 is fixed to the rear part of the lifting control link 27 closer to the manual operation means than the fulcrum pin 30, and the restricting tool 44 faces the rear surface of the position link 28. Therefore, the lifting control link 27
Is set to a predetermined angle with the plowing depth control lever 16,
The position link 28 is on the front side of the restrictor 44,
That is, forward and backward movement is allowed on the raising side, but movement rearward of the restrictor 44 is prevented. Although the pin-shaped restrictor 44 is directly fixed to the lift control link 27 in the embodiment, it may be fixed via a plate or the like.

In the figure, 42 is a piston rod lubrication pipe, 43 is a lever panel, 45 is a hydraulic hose, 46 is a left bracket of a shunt valve 47 for distributing pressure oil to lift arm actuation and horizontal control solenoid valves, Reference numeral 48 denotes a descending speed adjusting device. The intermediate part of the arm plate 48b is attached to the outer end portion of the adjusting shaft 48a of the descending speed adjusting device 48, and is fastened to the case by interposing a disc spring or the like. Braking by means of the connecting member 48c on the front of the arm plate 48b.
The flow control lever 48d is connected via the flow control lever 4d.
Since it acts as a balancer so that it does not tilt forward due to its own weight of 8d, the posture of the flow control lever 48d can be held by a small friction.
When 8d is fully pulled rearward, the rear portion of the arm plate 48b contacts the hydraulic housing 1 as a stopper, and when it is tilted forward, the seat portion of the adjusting shaft 48a contacts the tapered surface of the oil passage and stops.

The bracket 17 is shown in FIGS.
As shown in FIG. 13, a lateral reinforcing plate 17e, which is made of a thick iron plate having an L shape when viewed from the rear side, is welded to the rear portion of the L-shaped inner portion to connect the vertical portion and the horizontal portion, A lift arm angle sensor 49 is screwed to a vertically long mounting plate 17d fixed to the rear surface of the reinforcing plate 17e on the outer side, and the horizontal portion of the bracket 17 has the horizontal control electromagnetic sensor mounted on its lower surface. The valve 17a and the valve block 17b are prevented from being splashed with rainwater, and the valves 17a and 17b are prevented from colliding with an obstacle.

In the above-mentioned agricultural tractor, when the position control lever 15 is rotated back and forth, the arm 31 of the support shaft 15a, which rotates integrally with the position control lever 15, rotates the position arm 33 back and forth through the link 32, and thereby the position. Since the right side of the link 28 is moved back and forth with the feedback link 40 as a fulcrum, the spool 10a of the lift control valve 10 connected thereto via the link base 11 is moved back and forth, and the piston 7 and the piston rod 8 are moved. Since the power arm 5, the lift shaft 2 and the lift arm 3 rotate forward and backward, the tiller moves up and down. At the same time, with the rotation of the power arm 5, the link 41 of the feedback mechanism rotates the feedback link 40 back and forth with the position arm 33 as a fulcrum, and the front lower end thereof moves the lower step 28a of the position link 28 back and forth. As a result, the spool 10a moves back and forth to return to the neutral position.

When the plowing work is performed, the position control lever 15 is set to the lowest position and the plowing depth control lever 16 is set to an appropriate plowing depth. At that time, on the one hand, the right side of the position arm 33 pivots rearward to the maximum,
The control arm 36 is retracted to the set position, and the sensor arm 24 is at an angle corresponding to the detection value of the tilling depth detector. Then, during the plowing work, when the plowing depth is shallow, the sensor arm 24 rotates rearward due to the difference between the detection signal of the detector and the detection value of the lift arm angle sensor 49, so that the elevation control link 27 is restricted in position. When the link base 11 moves backward, the tilling device descends to a predetermined tillage depth, and when the detector issues a raising signal, the sensor arm 24 rotates forward,
The left side of the elevating control link 27 is pushed forward and the link base 11 moves forward against the return spring 12, so that the tiller moves up to the set working depth. Further, when the position control lever 15 is set to the raised position in order to rotate the aircraft, the position arm 33 rotates forward and pushes the right side of the position link 28 forward,
As a result, the link base 11 is also pushed out, so that the tiller moves up, and when the position control lever 15 is set to the lowest position after the machine has traveled, the tiller moves down.

Further, at the time of raising and lowering the working machine and controlling the raising and lowering,
Since the working depth control lever 16 side (right side) of the lifting control link 27 is configured as an upward step 27a, the control arm 3
6 can be lowered to near the upper surface of the position link 28, whereby the control arm 36 can be formed long and its working stroke can be sufficiently secured. Further, the opposite side (left side) of the position link 28 to the position control lever 15 is formed in the downward step 28a, so that even if the support shaft 20 serving as the upper fulcrum of the sensor arm 24 is set to a low position. Since the working length can be sufficiently secured and the vertical width of the downward step portion 28a is wide, the lower end of the feedback link 40 must be formed in accordance with the forward and backward rotation of the feedback link 40. Even if it moves up and down, it can be reliably received.

[0018]

According to the present invention, the working machine is connected to the rear part of the machine body by the top link and the left and right lower links so that the work machine can be moved up and down.
The left and right lift arms 3 that are operated by the lifting hydraulic cylinders 6 installed in the hydraulic housing 1 are connected to the lift rods 3a.
The lift control valve 10 of the hydraulic cylinder 6 is operated by the manual operation means and the work machine height detector, and the lift rod 3a is operated by the detection result of the horizontal detector. In the agricultural tractor having the horizontal control cylinder 4 interposed therein, one side of the hydraulic housing 1 that supports the position control lever 15 and the working depth control lever 16 serving as the manual operation means has an L shape when viewed from the front-rear direction. The bracket 17 is attached, and a retaining portion for preventing the lever 15 and the lever 16 from retaining is provided in a vertical portion of the bracket 17 along the side surface of the hydraulic housing 1, and the horizontal control cylinder 4 is provided on the lower surface of the horizontal portion. Solenoid valve for horizontal control 1 installed in the oil passage
7a is attached, so position control lever 1
5 and the bracket 17 formed with a lateral retaining stopper for the plowing depth control lever 16 is attached to the horizontal control electromagnetic valve 17a.
It can also be used as the supporting means, to simplify the mounting structure and reduce the cost. Further, since the reinforcing plate 17e for connecting the vertical portion and the horizontal portion is fixed to the L-shaped inner side portion of the bracket 17, and the lift arm angle sensor 49 is attached to the reinforcing plate 17e, the lift shaft of the hydraulic housing 1 is attached. Although the distance between 2 and the levers 15 and 16 is extremely narrow, the horizontal control electromagnetic valve 17a and the lift arm angle sensor 49 can be easily assembled to the hydraulic housing 1 with the bracket 17 attached. Further, since the reinforcing plate 17e is effectively used for mounting the lift arm angle sensor 49, a separate mounting plate is not required.
Further, the horizontal portion of the bracket 17 can prevent rainwater from splashing on the horizontal control electromagnetic valve 17a or collision of an obstacle.

[Brief description of drawings]

FIG. 1 is a side view of an agricultural tractor.

FIG. 2 is a side view of a control device for an agricultural tractor.

FIG. 3 is a partially cutaway bottom view of the same.

FIG. 4 is a vertical sectional view of the same.

FIG. 5 is a side view of an operation link mechanism and a feedback mechanism.

FIG. 6 is a plan view of a lifting control device.

FIG. 7 is a side view of a transmission mechanism of the work machine-to-ground height detector.

FIG. 8 is a side sectional view of a control device.

FIG. 9 is a perspective view of a main part of the control device.

FIG. 10 is a plan view of a bracket to which an operation lever and a horizontal control solenoid valve are attached.

FIG. 11 is a left side view of the above.

FIG. 12 is a rear view of the same.

FIG. 13 is a plan view of a main part.

[Explanation of symbols]

 1 Hydraulic Housing 10 Lift Control Valve 11 Link Base 15 Position Control Lever 16 Plowing Depth Control Lever 17a Horizontal Control Electromagnetic Valve 17e Reinforcing Plate 17d Mounting Plate 27 Lift Control Link 28 Position Link 44 Restrictor 49 Lift Arm Angle Sensor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinya Kanemoto 667 Isuya-cho, Higashi Izumo-cho, Yatsuka-gun, Shimane Prefecture 1 Inside Mitsubishi Agricultural Machinery Co., Ltd.

Claims (2)

[Claims] 1. A top rod and left and right lower links are connected to a rear portion of a machine body so that a working machine can be moved up and down, and left and right lift arms 3 operated by a lifting hydraulic cylinder 6 installed in a hydraulic housing 1 are lift rods. 3a is connected to the lower link, and the lift control valve 10 of the hydraulic cylinder 6 is operated by a manual operation means and a work implement height detector. In the agricultural tractor having the operating horizontal control cylinder 4 interposed therebetween, an L-shape is formed on one side of the hydraulic housing 1 supporting the position control lever 15 and the working depth control lever 16 as the manual operation means when viewed from the front-rear direction. The bracket 17 is attached, and the lever 15 and the lever 1 are attached to a vertical portion of the bracket 17 along the side surface of the hydraulic housing 1. 6. An agricultural tractor characterized in that a retaining block portion for preventing retaining with 6 is provided, and a horizontal control electromagnetic valve 17a interposed in the oil passage of the horizontal control cylinder 4 is attached to the lower surface of the horizontal portion. Work machine control device. 2. A reinforcing plate 17e for connecting a vertical portion and a horizontal portion is fixed to the L-shaped inner portion of the bracket 17, and the lift arm angle sensor 49 is attached to the reinforcing plate 17e.
The work implement control device for an agricultural tractor according to claim 1, wherein the work implement control device is attached.