JPH04107587U - Pressure oil supply device - Google Patents

Abstract

(57) [Summary] [Purpose] To enable manual operation even if a manual switching valve is suddenly operated, and to omit external piping. [Structure] A shaft hole 18 is formed in the shaft center of the spool 13 that communicates and blocks the inlet port 7, outlet port 8, and return port 6 of the electric switching valve 5, and the shaft hole 18 connects the return port 6 and the solenoid interior 16 A throttle 19 is provided on the inlet side of the shaft hole 18 to restrict the pressure oil flowing into the return port 6 from flowing into the solenoid interior 16, and the return port 6 is connected to the outlet side of the manual switching valve 3. Connect the inlet port 7 to the outlet side of the radio-controlled switching valve 4, and connect the outlet port 8 to the main valve 9.
which is connected to the pressure receiving part 10 of. [Effect] Even if the rise of the pressure oil flowing into the tank port 6 is sudden, the pressure inside the solenoid 16 is slowly increased and the return port 6 and outlet port 8 are not blocked by the spool 13. Even if it is operated, it can be operated manually, and there is no need to provide external piping to drain the pressure oil inside the solenoid 16.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is applicable to manually operated and radio-controlled work vehicles such as small power excavators. This invention relates to a pressure oil supply device used for.

0002

[Conventional technology]

As shown in Figure 1, a manual switching valve 3 and a radio-controlled switching valve are installed in the discharge path 2 of the hydraulic pump 1. A valve 4 is provided, and the output side of the manual switching valve 3 is connected to the return port 6 of the electric switching valve 5. , the output side of the radio-controlled switching valve 4 is connected to the inlet port 7 of the electric switching valve 5, and its output side is connected to the inlet port 7 of the electric switching valve 5. Connect the port 8 to the pressure receiving part 10 of the main valve 9 to connect the main valve 9 to the manual switching valve 3. A pressure oil supply device in which switching is possible using an electric switching valve 5 is known.

0003

[Problem that the idea aims to solve]

The electric switching valve 5 used in such a pressure oil supply device has a valve body as shown in FIG. The spool 13 is inserted into the valve hole 12 of 11, and the spool 13 is held in the blocking position by the spring 14. It has a structure in which it is held in position and pushed to the communicating position by solenoid 15. When the inlet pressure entering the return port 6 suddenly rises, the pressure inside the solenoid 16 becomes higher than the pressure at the outlet port 8, and the spool 13 is pushed in the blocking direction and exits. Manual operation when the manual switching valve 3 is suddenly operated because pressure oil cannot be supplied to the port 8. become unable. As a way to solve this problem, the leaked pressure oil inside the solenoid 16 can be removed. It is known to install external piping for draining, but this is undesirable in terms of space and piping costs. It is advantageous.

0004 Therefore, the present invention provides a pressure oil supply device that can solve the above-mentioned problems. The purpose is to

[Means to solve the problem]

A shaft hole is formed in the spool shaft center of the electric switching valve to connect the return port and the inside of the solenoid. It communicates with the shaft hole and has a restriction on the inlet side.

[Effect]

The throttle causes the pressure inside the solenoid to rise slowly and the spool returns to the port. The manual switching valve can be It can be operated manually even when suddenly operated, and there is an external drain to drain the pressure oil inside the solenoid. No piping required.

[0005]

【Example】

As shown in FIG. The shaft hole 18 is connected to the return port 6, and a throttle 19 is provided on the inlet side of the shaft hole 18. There is. Therefore, the pressure oil that has flowed into the return port 6 will flow into the solenoid interior 16. Since the pressure inside the solenoid 16 is limited by the throttle 19, the pressure rise inside the solenoid 16 is slow and the return Even if the inlet pressure of port 6 rises suddenly, the spool 13 does not move in the blocking direction. Therefore, manual operation is possible even if the manual switching valve 3 is suddenly operated, and the solenoid There is no need to provide external piping to drain the pressure oil inside 16.

[0006]

[Effect of the idea]

A throttle 19 prevents the pressure oil that has flowed into the return port 6 from flowing into the solenoid interior 16. Since the internal pressure inside the solenoid 16 can be increased slowly by limiting the Even if the inlet pressure of port 6 suddenly rises, spool 13 blocks return port 6 and outlet port 8. Even if you suddenly operate the manual switching valve 3, it will not move in the direction of This eliminates the need for external piping to drain the pressure oil inside the solenoid 16, saving space. , piping costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram of a conventional pressure oil supply device.

FIG. 2 is a sectional view of a conventional electric switching valve.

FIG. 3 is an explanatory diagram of a pressure oil supply device showing a conventional example.

[Explanation of symbols]

1 Hydraulic pump, 2 Discharge path, 3 Manual switching valve, 4
Radio-controlled switching valve, 5 Electric switching valve, 6 Return port, 7
Inlet port, 8 Outlet port, 9 Main valve, 10
Pressure receiving part, 11 valve body, 12 valve hole, 13 spool,
14 spring, 15 solenoid, 16 inside solenoid, 18 shaft hole, 19 aperture.

Claims (1)

[Scope of utility model registration request] Claim 1: A discharge passage 2 of a hydraulic pump 1 is connected to the inlet side of a manual switching valve 3 and a radio-controlled switching valve 4, and an outlet side of the manual switching valve 3 is connected to a return port 6 of an electric switching valve 5. death,
The outlet side of the radio-controlled switching valve 4 is connected to the inlet port 7 of the electric switching valve 5, the outlet port 8 is connected to the pressure receiving part 10 of the main valve 9, and the electrical switching valve 5 is connected to the valve of the valve body 11. A spool 13 is inserted into the hole 12, and the spool 13 is held in a position where the spring 14 blocks the inlet port 7 and the outlet port 8 and the outlet port 8 is communicated with the return port 6, and the solenoid 15 connects the inlet port 7 and the outlet port. The structure is such that the port 8 is pushed to a position where the return port 6 and the outlet port 8 are communicated, and an axial hole 18 is formed in the axial center of the spool 13 to communicate the return port 6 with the inside 16 of the solenoid.
A pressure oil supply device characterized in that a throttle 19 is provided on the inlet side of the pressure oil supply device.