JPH0139124Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a hydraulic control device for a working machine, etc., which raises and lowers the working machine relative to the main machine, such as the reaping section of a combine harvester.

Conventionally, this type of hydraulic control device controls the lifting and lowering of the work equipment manually or by electric signals from a switch means such as a sensor. It was constructed using an electromagnetic directional valve and was electrically controlled. However, electromagnetic directional control valves are very expensive compared to manual directional control valves, and they also leak a large amount of hydraulic pressure, making it impossible to prevent the work equipment from falling naturally unless a pilot check valve is also installed. The equipment as a whole was becoming increasingly expensive.

In view of the above-mentioned conventional circumstances, the present invention consists of a directional control valve as a manual directional control valve, and the spool operating arm 11 of the manual directional control valve 4, which is biased in one direction by a weak spring 13, is replaced by a strong spring 13. 10 is engaged with the pin 9a of the manual operating arm 9 which is always biased to the neutral position to regulate the position, and furthermore, the solenoid control mechanism 12 operated by the switch means is operated against the weak spring 13 to control the spool operating arm 9. By configuring 11 so that it can be operated independently, it can be controlled by manual lever operation using a manual directional control valve and electric signals from the switch means, and the device can be constructed extremely easily and inexpensively, and has priority over manual operation. By activating the solenoid control mechanism and preventing the manual lever from moving even when the solenoid control mechanism is activated, there is no risk of injury to the operator due to contact with the manual lever due to unexpected movement.
The present invention aims to provide a hydraulic control device for work logs, etc., which allows work to be carried out safely.

The structure of the present invention will be described with reference to an embodiment shown in the drawings. The drawings show a lifting control device for the reaping section of a combine harvester, and in FIGS. 1 and 2, 1 indicates the reaping section ( Work machine), 2 is a hydraulic cylinder, one end of which is supported by a combine machine stand (not shown) and the other end is connected to the reaping section 1, and the reaping section 1 is operated by the expansion and contraction of the cylinder 2. The table is rotated up and down around the upper rotation fulcrum. 3 is a hydraulic pump; 4 is a manual directional switching valve; by selecting the switching position, pressure oil discharged through the oil tank 5 and the hydraulic pump 3 is supplied to the cylinder 2 to raise the reaping section 1; It can be moved up, stopped, and lowered. Note that 6 is a relief valve.

On the other hand, in FIGS. 3 to 5, reference numeral 7 denotes a hydraulic lift lever provided in the operating section of the combine, 8 is a link thereof, 9 is an arm, 10 is a return spring that returns the hydraulic lift lever 7 to the neutral position, and 10a
is a stopper pin of the return spring 10, and constitutes a manual operation mechanism for manually operating the manual directional control valve 4.

The arm 9 of the hydraulic lift lever 7 is rotatably fitted into a small diameter portion 4b provided at the tip of the spool operating shaft 4a of the manual directional control valve 4.
A pin 9a provided on the arm 9 is engaged with an arm 11 (coupling member) that is attached to a two-chamfered portion 4c formed on the small diameter portion 4b and rotates integrally with the spool operating shaft 4a. Further, the arm 11 is rotated by the pressure of the solenoid 12, and
Although the spring 13 has a weaker biasing force than the return spring 10 of the hydraulic lifting lever 7, it biases the arm 11 toward the pin 9a.

FIG. 6 shows a circuit diagram of the solenoid control mechanism, where 14 is a switch that closes in conjunction with the reverse operation of the main gear shift lever of the combine, and 15 is a switch that opens when the reaping section 1 rises and reaches the appropriate position. It's a switch. Therefore, the solenoid 12 is energized to press the arm 11 and switch the manual directional control valve 4 when the main shift lever is in the reverse position and the reaping section 1 is in a certain downward range.

In the structure as described above, the reaping part 1
The lifting and lowering of the arm 9 is performed by lowering the hydraulic lifting lever 7 or operating it to the raised position.When the hydraulic lifting lever 7 is operated to the lowering position at the start of reaping, the arm 9 rotates clockwise around the spool operating shaft 4a. move. The arm 11 is biased by a spring 13 to a pin 9a provided on the arm 9.
The spool operating shaft 4a rotates to switch the manual directional control valve 4 to the lowering side of the reaping section 1, and the reaping section 1 is connected to the hydraulic cylinder 2.
The oil inside is discharged into the oil tank 5 and the oil is lowered.
Furthermore, when the hydraulic lift lever 7 is operated to the raised position when the machine turns or at the end of mowing, the arm 9 rotates to the left around the spool operating shaft 4a, and the pin 9a rotates the arm 11 against the spring 13. Therefore, the spool operating shaft 4a switches the manual directional control valve 4 to the raising side of the reaping section 1, and the reaping section 1 is raised by filling the cylinder with pressure oil from the hydraulic pump 3.

In this case, when the aircraft moves backward to correct its direction as the aircraft turns, the switch 14 closes and the solenoid 12 is energized when the main gear shift lever is placed in the reverse position. 11 to the left, manual directional control valve 4
is switched to the raising side of the reaping part 1, and the reaping part 1 is raised to a predetermined raised position where the switch 15 is opened. Therefore,
The reaping section 1 can be automatically raised simply by placing the main gear shift lever in the reverse position without requiring the driver to perform complicated operations such as operating the hydraulic lift lever 7 to the upward side as the machine moves backward. can. Also,
At this time, the hydraulic lift lever 7 is held at the neutral position by the return spring 10, so that the linkage with the arm 11 is broken, and the hydraulic lift lever 7 does not move to the upward side due to the excitation of the solenoid 12.

In short, the present invention connects a control member of a working machine or the like to a hydraulic device consisting of a hydraulic pump, a directional control valve, a hydraulic cylinder, etc., and controls the directional control valve by manual lever operation and an electric signal from a switch means. In a hydraulic control device configured to operate or stop a control member by switching,
The directional control valve is constituted by a manual directional control valve, and the spool operation arm 11 of the manual directional control valve 4, which is urged in one direction by a weak spring 13, is always urged to a neutral position by a strong spring 10. The weak spring 13 engages with the pin 9a of the manual operation arm 9 to regulate the position, and further controls the solenoid control mechanism 12 operated by a switch means.
Since the spool operating arm 11 is configured to be able to be operated independently in opposition to It can be directly connected to the arm 11, does not require a special clutch for switching between manual and automatic modes, and does not require a complicated electric circuit, and the device itself can be configured extremely simply and inexpensively.

Moreover, when the solenoid control mechanism is activated, it only allows the spool operating arm 11 to be operated independently against the weak spring 13, and the manual lever still maintains the neutral position and does not move even with the strong spring 10. The solenoid control mechanism can be activated prior to operation, and the operator can work safely without the risk of injury due to accidental movement of the manual lever, which is extremely useful in practical use. This is effective.

[Brief explanation of drawings]

The drawings show an embodiment of the hydraulic control device for working machines, etc. according to the present invention, in which Fig. 1 is a side view of the reaping section of a combine harvester, Fig. 2 is a hydraulic circuit diagram, and Fig. 3 is a hydraulic circuit diagram.
Figures 4 to 4 are side views and plan views showing the main parts of the hydraulic control device, respectively, and Figure 5 is an exploded view of the main parts.
FIG. 6 is a solenoid control circuit diagram. DESCRIPTION OF SYMBOLS 1...Reaping part (control member), 2...Hydraulic cylinder, 3...Hydraulic pump, 4...Manual directional switching valve, 4a...Spool operating member, 7...Hydraulic lifting lever, 11...Arm (linkage) parts), 12...
Solenoid, 14...Switch that closes in conjunction with the reverse operation of the main gear shift lever.

Claims (1)

[Scope of utility model registration request] A control member of a work machine or the like is connected to a hydraulic device consisting of a hydraulic pump, a directional control valve, a hydraulic cylinder, etc., and the directional control valve is switched by manual lever operation and an electric signal from a switch means to operate the control member, or In the hydraulic control device which is designed to be in a stopped state, the directional control valve is constituted by a manual directional control valve, and the spool operating arm 11 of the manual directional control valve 4, which is biased in one direction by a weak spring 13, is The spring 10 engages with the pin 9a of the manual operation arm 9, which is always urged to the neutral position, to regulate the position, and the solenoid control mechanism 12, which is operated by a switch means, is operated against the weak spring 13 to operate the spool. A hydraulic control device for a work machine, etc., characterized in that an arm 11 is configured to be operable independently.