JPH04129902U - Operation valve device - Google Patents

Abstract

(57) [Summary] [Purpose] To enable a cut-off valve to be retrofitted to an operating valve. [Configuration] Cut-off valve 21 in valve body 2 of operation valve 1
A plurality of connection ports are formed on the connecting surface 2a of the valve body 2 and the connecting surface 22a of the valve body 22, and the valve body 2 has an inlet passage 15 connected to the connecting port. A pump port 11 is formed that communicates with the drain passage 17, the neutral passage 19, and the inlet passage 15, and the valve body 22 has a communication passage 30 connected to some connection ports, a drain passage 33 connected to the remaining connection ports,
The valve body 2 of the operation valve 1 is provided with pump ports 25 and 26 that are open to the communication passage 30, and relief valves 23 and 24 that communicate the communication passage 30 with the drain passage 33 when the pressure in the communication passage 30 is higher than a set pressure. The valve body 22 of the cut-off valve 21 can be retrofitted.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention can be used in hydraulic circuits of construction machinery such as wheel loaders and dump trucks. The present invention relates to an operating valve device.

0002

[Conventional technology]

Actuators and steering wheels for work equipment such as boom cylinders and arm cylinders For construction machinery equipped with hydraulic cylinders, multiple hydraulic pumps are installed on the work equipment actuator. By supplying pressure oil from the pump, a large flow rate can be supplied to the actuator for work equipment, increasing the operating speed. Hydraulic circuits that speed up the process are known. The operating valve device that constitutes such a hydraulic circuit has multiple hydraulic pumps connected to the valve body. form multiple inlet ports connected to each other and connect the multiple inlet ports with a spool. It is configured to communicate with and shut off the actuator. In the above-mentioned hydraulic circuit, the pressure oil discharged from multiple hydraulic pumps is transferred to the work machine during high loads. When supplied to the actuator, the pressure of the discharge pressure oil exceeds the set pressure of the relief valve. If the drive horsepower of multiple hydraulic pumps exceeds the engine output, the engine will stop. Because of this, the discharge pressure oil of one hydraulic pump is leaked into the tank and is in an unloaded state. A cut-off valve is installed in the pump piping to prevent the engine from stopping.

0003

[Problem that the idea aims to solve]

As mentioned above, the cut-off valve is installed in the middle of the pump piping, so there is no need for extra piping. Also, the number of seal parts increases, making piping work troublesome, and the number of oil leakage points increases, resulting in oil leakage. reliability is reduced.

0004 Therefore, this invention is an operating valve that allows a cut-off valve to be retrofitted to the operating valve. The purpose is to provide equipment.

[0005]

[Means to solve the problem] A cut-off valve 21 is installed in the valve body 2 of the operation valve 1 that supplies pressure oil to the actuator. A valve body 22 is connected to the valve body 2, and an inlet port is connected to the valve body 2 to communicate with the pump port 11. 15, the neutral passage 19, the drain passage 17, and the connecting surface 2a. A plurality of communicating connection ports are formed, and the valve body 22 has a plurality of connecting ports communicating with the pump port. If the pressure inside the communicating passage 30, drain passage 33, and communicating passage 30 is higher than the set pressure. A relief valve is provided which operates to drain water into the drain passage 33. A plurality of connection ports are formed on the connection surface 22a of the main body 22 to connect with the connection ports. The communication passage 30 and the drain passage 33 are connected to each of these connection ports.

[Effect]

Connecting the valve body 22 of the cut-off valve 21 to the valve body 2 of the operation valve 1 Then, the cut-off valve supplies pressure oil discharged from the hydraulic pump to the operation valve to operate the actuator. The discharge pressure oil of multiple hydraulic pumps can be combined and supplied to the actuator. When the supply pressure is high, the discharge pressure oil of the hydraulic pump connected to the cut-off valve 21 is It can flow into the tank and become unloaded.

[0006]

【Example】

As shown in FIG. 1, the operating valve 1 has a first spool 3 and a second spool 4 on the valve body 2. It has a boom valve 5 and a bucket valve 6, and the valve body 2 has a first and a second valve. ・Third and fourth actuator ports 7, 8, 9, 10 and pump port 11 and tank A first, second, and third connection port 12 is formed on the connecting surface 2a of the valve body 2. ports 12, 13, 14 are formed, and first and second actuator ports 7, 8 is connected to the output side of the boom valve 5, and the third and fourth actuators 9 and 10 are connected to the bucket The pump port 11 is connected to the output side of the valve 6, and the pump port 11 is connected to the inlet of the bucket valve 6 through the inlet passage 15. It is connected to the port 6a and to the discharge side of the first hydraulic pump 16, and the tank Port 12 communicates with drain passage 17 and is connected to tank 18 . The first connection port 12 is connected to the inlet passage 15, and the second connection port 13 is connected to the drain. The third connection port 14 is connected to the neutral passage 19, and the third connection port 14 is connected to the neutral passage 19. The passage 19 passes through the bucket valve 6 and the neutral ports 6b and 5b of the boom valve 5, and then connects to the drain. 17 and to the inlet port 5a of the boom valve 5 via check 20. are doing. The cut-off valve 21 has first and second relief valves 23 and 24 in the valve body 22. First and second ports 25 and 26 are formed in the valve body 22, and the operation The connecting surface 22a connected to the connecting surface 2a of the valve body 2 of the valve operation 1 has a first, a second, and a third. Connection ports 27, 28, 29 are formed, and the first pump port 25 and the first connection The port 27 and the third connection port 29 communicate through a communication path 30, and the second pump port 26 is connected to the communication passage 30 by a first passage 32 provided with a check valve 31 and has a first release The outlet port 23b is connected to the drain passage 3. 3 is connected to the second connection port 28, and the inlet port 24a of the second relief valve 24 is connected to the second connection port 28. 1. Connected to the second pump port 26 with a second passage 36 equipped with second throttles 34 and 35. , the outlet port 24b of which is connected to the drain passage 33 by a third passage 37; The relief valve 24 is pushed in the communication direction by the pressure of the first pump port 25, and the spring force and output The first and second pump ports 25, 2 are pushed in the blocking direction by the mouth pressure. 6 is connected to the discharge sides of the second and third hydraulic pumps 38 and 39.

[0007] Next, the operation will be explained. When the load on the boom cylinder 40 and bucket cylinder 41 is small, the supply pressure is low. Because the temperature is low, the first and second relief valves 23 and 24 do not operate to provide relief. The pressure oil discharged from the third hydraulic pumps 16, 38, and 39 can be combined and supplied to each cylinder. . When the load on the boom cylinder 40 and bucket cylinder 41 is large, the supply pressure is Since the height is high, the second relief valve 24 is pushed to the communicating position and the pressure oil in the second passage 16 is stagnated. The first relief valve 23 is in the communication position, and the third hydraulic pump 39 The discharge pressure oil flows through the drain passage 33, the second connection port 28, and the second connection port of the valve body 2. It flows into the tank 18 from the tank 13, the drain passage 17, and the tank port 12, and is unloaded. The pressure oil discharged from the first and second hydraulic pumps 16 and 38 is supplied to each cylinder. This can prevent the engine that is supplied with the hydraulic power and drives each hydraulic pump from stopping. In addition, when the cut-off valve 22 is not required, a valve body 2 formed in the valve body 2 of the operating valve 1 can be used. Connect the discharge sides of the second and third hydraulic pumps 38 and 39 to the first and third connection ports 12 and 14. Then, just close the second connection port 13 with a plug and close the cutoff valve 22. It can be retrofitted or removed as needed. Figure 2 shows an operation valve with a service valve 50 installed between the operation valve 1 and the cut-off valve 21. This service valve 50 has a valve main body 51 and a spool 52. It supplies pressure oil to one of the actuator ports 53, 53 of the valve main A pump passage 54 and a drain passage 5 penetrate through both connecting surfaces 51a and 51b of the body 51. 5. A neutral passage 56 is formed, and the pump passage 54 is connected to the inlet port via a check valve 57. The neutral passage 56 opens and communicates with the neutral port 59, and the valve of the operation valve 1 One connecting surface 51a is connected to the connecting surface 2a of the main body 2, and the other connecting surface 2b is cut. By connecting the connecting surfaces 22a of the valve body 22 of the off valve 21, each first connection point is connected. The ports 12 and 27 are connected through a pump passage 54, and each second connection port 13 and 28 is connected to a drain. The third connection ports 14 and 29 are communicated with each other through a neutral passage 56. , the first, second, and third hydraulic pumps 1 are connected to the actuator port 53 of the service valve 50. 6, 38, and 39 discharge pressure oils can be supplied.

[0008]

[Effect of the idea]

The valve body 22 of the cut-off valve 21 is connected to the valve body 2 of the operation valve 1, and the valve body 22 of the cutoff valve 21 is connected to the valve body 2 of the operation valve 1. Since a to-off valve can be retrofitted, the number of pipes and seals are reduced, reducing piping work. It's easier, the number of oil leak points is reduced, and oil leak reliability is improved. The discharge side of the first hydraulic pump is connected to the pump port of the valve body 2 of the operation valve 1, The discharge side of the other hydraulic pump is connected to the valve body 22 of the cut-off valve 21. If a pump port is formed in the valve body 22 so as to communicate with the communication passage 30, the hydraulic pressure can be increased. The number of pumps can be increased.

[Brief explanation of drawings]

FIG. 1 is a schematic structural explanatory diagram showing an embodiment of the present invention.

FIG. 2 is a schematic configuration explanatory diagram with a service valve attached.

[Explanation of symbols]

1 Operation valve, 2 Valve body, 11 Pump port, 12
First connection port, 13 Second connection port, 14 Third connection port, 15 Inlet passage, 16 First hydraulic pump, 17
Drain passage, 19 Neutral passage, 20 Cut-off valve, 21 Valve body, 25 First pump port, 26
2nd pump port, 27 1st connection port, 28 2nd connection port, 29 3rd connection port, 30 communication path,
33 drain passage, 38 second hydraulic pump, 39 third
Hydraulic pump.

Claims (1)

[Scope of utility model registration request] Claim 1: A valve body 22 of a cut-off valve 21 is attached to a valve body 2 of an operation valve 1 that supplies pressure oil to an actuator.
an inlet passage 15 communicating with the pump port 11, a neutral passage 19, a drain passage 17, and a plurality of connection ports opening into the connecting surface 2a and communicating with each passage are formed in the valve body 2, and the valve body 22 is provided with a communication passage 30 communicating with the pump port, a drain passage 33, and a relief valve that operates for relief and flows out into the drain passage 33 when the pressure in the communication passage 30 exceeds a set pressure, and the connection surface of the valve body 22 22a is formed with a plurality of connection ports connected to the connection port, and each connection port is connected to the communication path 3.
0. An operating valve device characterized in that a drain passage 33 is connected.