JPH0541621Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Field of Application> This invention relates to a device for setting the height of a pre-processing section of a combine harvester.

<Conventional technology> The cutting height of grain culms with a combine harvester varies depending on the soil quality of the field, the depth of cultivated soil, the difference between wet fields and dry fields, etc., so that the cutting height can be adjusted uniformly at the same height in fields with the same conditions. For combine harvesters, a mechanism is generally known in which the entire pre-processing section is swung up and down using a hydraulic cylinder in order to raise and lower the reaping device. A potentiometer for cutting height command and a potentiometer for cutting height detection are installed in the system or operation system, and when the pre-processing part (reaping part) is lowered with the hydraulic lever, the signal of the detection potentiometer is the command signal. When it becomes equal to , the oil passage of the hydraulic cylinder is cut off using an electromagnetic valve, and the reaping section is stopped at the working height.

In addition, mechanically, the cylinder operating valve is mechanically operated with a hydraulic lever to lower the reaping section, but the lowering operation of the reaping section is fed back to the hydraulic lever with a wire etc. until the reaping section reaches the set position. A device has been devised in which, when lowered, the hydraulic lever returns to the neutral position and the lowering of the reaping section is stopped at the working position.

<Problems to be solved by the invention> However, among the above devices, those that use an electric control system have excellent responsiveness and operability, but are expensive and have problems such as the inability to immediately repair a failure on the user side. However, in the latter mechanical control method, which is intended to improve this problem, the manual lever operated by the operator swings strongly in reverse as the reaping section descends, causing shock and discomfort to the operator and causing the operating system to The operability and responsiveness were poor due to play in the feedback system and the feedback system, and the drawback was that the lower limit position varied.

<Means for Solving the Problems> The device of the present invention for solving the above-mentioned problems has a pre-processing section 2 attached to the front of the machine body 1 so as to be able to swing vertically, and a solenoid controlled by operating the operating section. The valve 12 is controlled to raise and lower the preprocessing section 2 using the hydraulic cylinder 6, and the operating position of the preprocessing section 2 is detected by a detection switch via the interlocking section 25, and the solenoid valve 12 is controlled to provide feedback. In a combine harvester that stops and maintains the lowering of the pre-processing section 2 at a preset lowering setting position, there is an operation switch 13a that operates the solenoid valve 12 by operating the operation section, and a feedback operation of the interlocking section 25 that operates the solenoid valve 12. The present invention is characterized in that it is provided with a detection switch 13b that operates the hydraulic cylinder 6 by controlling the .

<Operation> By operating the operating section such as the operating lever 9 in the "up" or "down" direction, the operating switch 13a, the solenoid valve 12, and the hydraulic cylinder 6 are actuated, and the preprocessing section 2 is operated to move up and down.

As the pre-processing section 2 moves up and down, the interlocking section 25 operates the detection switch 13b to close the solenoid valve 12.
By controlling the hydraulic cylinder 6 and activating or stopping the hydraulic cylinder 6, the preprocessing section 2 is stopped and held at the lowered setting position.

<Example> As shown in Figs. 1 to 3, a preprocessing section 2 is attached to the front of a combine harvester body 1 so as to be able to swing around a fulcrum 3, and 4 and 5 have their rear ends attached to the These are a transmission shaft that also serves as a preprocessing frame and a swinging rod that is pivotally supported on a fulcrum 3. A hydraulic cylinder 6 for swinging the pretreatment section 2 is installed between the lower surface of the transmission shaft 4 and the machine body 1 side, and the hydraulic cylinder 6 is driven by a hydraulic pump 7 attached to the machine body 1 side. Ru.

An operating lever 9 for controlling the valves of the hydraulic pump 7 is provided near the driver's seat 8, and a lever shaft 11 is rotatably supported at the base end of the operating lever 9 on a frame 10a on the aircraft body side. One end is fixed to the lever shaft 11, and the lever shaft 11 is further provided with an operating switch 13 such as a rotary switch that turns on and off the solenoid valve 12 by swinging the operating lever 9.
a is attached, and the hydraulic cylinder 6 is actuated by the swinging operation of the operating lever 9, and the preprocessing section 2 is moved up and down. The operating lever 9 is biased by a spring 15 so as to always return to the neutral position (hydraulic cylinder stop operating position) as shown in FIG. It has a mechanism that allows it to rise or fall.

An upwardly facing plate 16 is fixed to the base end of the swinging rod 5, and a safety lever 17 is attached to the side surface of the plate 16, the rear end of which is rotatably supported by a pin 18. The safety lever 17 has an arc-shaped slit 19 with the pin 18 at its center so that the tip can swing up and down within a certain angle range, and a plate 16 is formed in the slit 19.
A guide pin 20 fixed to the plate 16 is housed in the safety lever 17, and in a normal state, the safety lever 17 is swung downward with respect to the plate 16 and is fastened to the plate side by the bolt head of the guide pin 20 or a nut screwed therein. It constitutes a accommodating mechanism 23, which will be described later.

The outer wire 2 is attached to the tip of the safety lever 17.
5a and an inner wire 25b.
One end of the inner wire 25b is fixed, and the same end of the outer wire 25a is fixed with a wire stopper 26 protruding from the frame 10b. The other end of the outer wire 25a is connected to the operating lever 2, which has one end rotatably supported on the support shaft 14 near the lever shaft 11.
7, and the inner wire 25 at the same end.
b is locked to the upper end of the rear relay lever 28. The operating lever 27 is always urged forward in a forward tilting direction by a spring 14a stretched between it and the frame 10a.

The relay lever 28 is rotatably supported on the frame 10a side by a relay shaft 29 projecting laterally and via a bracket 30.
A cam element 31 is provided protruding from the end of the relay lever 28 so as to rotate together with the relay lever 28. A regulating shaft 32 that is rotatably supported in the horizontal direction by the bracket 30 is erected at a position close to the cam element 31, and a knob 33 is attached to the upper end of the regulating shaft 32. Belleville spring 3 pressed against the top surface
4 is fitted to the base end portion, and the regulating shaft 32 is configured to prevent accidental rotation.

A flange-shaped regulating member 35 is tilted and fixed to the regulating shaft 32, and the upper part of the cam member 31 touches the lower surface of the regulating member 35, thereby regulating the clockwise rotation of the cam member 31 (FIG. 1). By rotating the regulating member 35, the clockwise rotation stop position of the cam member 31 can be adjusted by changing the contact attitude with the lower surface of the regulating member 35. As a result, the amount of retraction of the inner wire 25b fixed to the relay lever 28 can be adjusted and regulated, and the adjustment section 24 is constituted by a series of these mechanisms.

Further, a detection switch 13b such as a rotary switch is attached to the support shaft 14 of the operating lever 27, and the detection switch 13b is connected to the operating lever 27.
7 is turned on and off by swinging due to the feedback operation of the interlocking section 25, and the pre-processing section 2
“ON” is activated when the lowering position has been lowered to the lowering setting position.
The solenoid valve 12 is set to neutral to stop the lowering operation of the pretreatment section 2 by the hydraulic cylinder 6.

In the above mechanism, when the operation lever 9 is swung clockwise from neutral and the pretreatment section 2 is lowered by the operation of the operation switch 13a and the solenoid valve 12, the inner wire 25b moves the relay lever 28 clockwise. However, as a result of this rotation, the cam 31 comes into contact with the lower surface of the regulating member 35 which has been set to rotate in advance, and if the pre-processing section 2 continues to descend, the loop of the inner wire 25b is reduced and the outer wire 25a is rotated. The end is pushed out backwards (to the left in Figure 1), and the actuating lever 27 is moved by the spring 1.
4a to the left, the detection switch 13b and the solenoid valve 12 are actuated to control the hydraulic pressure from the hydraulic pump 7 to the hydraulic cylinder 6, and the lowering of the preprocessing section 2 is also stopped. It will remain in that state.

As is clear from these effects, knob 3
3 to adjust the rotation position of the regulating member 35, the right rotation limit position of the relay lever 28 is set. It will be decided whether it becomes neutral and its descent is stopped. The lowering position of the preprocessing section 2 is adjusted by the adjustment section 24 up to the lower limit position at which the preprocessing section 2 is received by the body frame and stopped.

In the above mechanism that operates as described above, if the mowing height is set by the pre-processing section 2 using the regulating member 35 at a position higher than the lower limit position for a long time and the hydraulic pump 7 is stopped, the hydraulic cylinder 6 The hydraulic system leaks due to the load of the pre-processing section 2, and the pre-processing section 2 is further lowered from the position where the cutting height is set. As a result, even if the operating lever 9 is tilted to the left from neutral and swung to the preprocessing raised position, the hydraulic pump 7 cannot be expected to return the preprocessing section 2 to the upward position, and there is a risk that troubles such as cutting of the inner wire 25b may occur. .

At this time, the flexibility mechanism 23
At the guide pin 20 which is the fastening part between the safety lever 17 and the plate 16, the safety lever 17 slips against the plate 16 and rotates upward within the arc of the slit 19, and the pre-processing section 2 This mechanism prevents troubles such as breakage of the inner wire 25b and deformation of the relay lever 28 and the safety lever 17 before it hits the under stopper 38. Such accommodation mechanism 2
3 can be provided not only at the lower end of the interlocking section 25 but also at the end on the adjusting section 24 side.

4 and 5 show different embodiments of the hydraulic control system of the device of the present invention, and FIG. 4 is a basic circuit diagram necessary for the operation of the device described above.

FIG. 5 shows a system in which a control system for raising and lowering the pre-processing section 2 and a control system for automatic adjustment operation, which always automatically stops at the set lowering position even during normal working conditions other than during raising and lowering operations, are provided separately. be.

In this example, when the automatic adjustment switch 13c is closed, the relay _R1 is activated and the self-holding switch 13 is closed.
e is closed and self-held, and either the "up" or "down" contact of the detection switch 13b is closed by the posture of the operating lever 27 corresponding to the descending posture of the preprocessing section 2, and the hydraulic pressure is applied via the solenoid valve 12. The cylinder 6 is operated and the pre-processing section 2 is stopped at the lower setting position. At this time, the detection switch 13
Both contacts b are open, and the cutting height set lamp L is lit to notify the operator.

The operation switch 13a is activated by operating the operation lever 9.
When the "raise" or "lower" contact is closed, the solenoid valve 12 is operated and the hydraulic cylinder 6 is operated "raise" or "lower", but at this time, the relay _R2 is activated and the switch of the self-holding circuit is activated. The circuit that opens 13e and automatically adjusts and maintains the cutting height does not operate, and the cutting height set lamp L does not light up.

<Effects of the invention> Since the present invention is constructed as described above, the cost is significantly reduced compared to the conventional method that uses expensive parts such as potentiometers to set the cutting height in the pre-treatment section, and the cost is significantly reduced. The system is easy to maintain, has better operability and responsiveness than systems that control everything mechanically, and accurately stops the preprocessing section at the set lowering position, eliminating variations in the stopping position. It has the advantage that it does not occur.

Particularly, it has the effect of preventing reverse operation or impact on the operating section due to feedback operation that occurs in mechanically controlled systems.

[Brief explanation of the drawing]

The drawings show one embodiment of the device of the present invention; Fig. 1 is an extracted side view of the main parts of the device, Fig. 2 is a perspective view showing the device of the present invention assembled into a combine harvester, and Fig. 3 is a cutting height diagram. The plan view of the height setting device, FIGS. 4 and 5 are circuit diagrams of the hydraulic system and the electrical system showing different embodiments of the control system of the device of the present invention. DESCRIPTION OF SYMBOLS 1... Airframe, 2... Preprocessing section, 7... Hydraulic pump, 9... Operating lever, 12... Solenoid valve, 13a... Operating switch, 13b... Detection switch, 24... Adjustment unit, 25... ...Interlocking part, 25
a... Outer wire, 25b... Inner wire.

Claims (1)

[Scope of utility model registration request] The pretreatment unit 2 is attached to the front of the machine 1 so that it can swing up and down, and the solenoid valve 1 is activated by operating the operation unit.
2 to raise and lower the pre-processing section 2 with a hydraulic cylinder 6, detecting the operating position of the pre-processing section 2 with a detection switch via an interlocking section 25, and controlling the solenoid valve 12 to provide feedback; In a combine harvester that stops and maintains the lowering of the pre-processing section 2 at a preset lowering position,
an operating switch 13a that operates the solenoid valve 12 by operating the operating section; and an operating switch 13a that operates the solenoid valve 12 by operating the operating section;
5. A pre-processing section height setting device for a combine harvester, which is provided with a detection switch 13b which operates a hydraulic cylinder 6 by controlling a solenoid valve 12 through the feedback operation of FIG.