JP2627066B2 - Operating valve device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an operation valve device for supplying pressure oil to an actuator such as a cylinder or a motor.

[Conventional technology]

As shown in FIG. 7, the main spool 5 which communicates the inlet port 2 to the valve body 1 with the first and second oil holes 3, 4 and the first and second spools which communicate with the first and second oil holes 3, 4. The second outlet ports 6, 7 and the first
A check valve 8 and a vacuum prevention valve 9 are provided between the oil hole 3 and the second oil hole 4, respectively, and the main spool 5 is moved left and right to change the inlet port 2 to the first outlet port 6 or the second outlet Connects to port 7 and transfers hydraulic oil from hydraulic source P to actuator B
To the first and second chambers B ₁ and B ₂ , and to prevent the backflow of pressure oil from the first and second outlet ports 6 and 7 to the inlet port 2 by the check valve 8 and to prevent vacuum. Tank port 10 with valve 9
There is known an operation valve device that absorbs pressure oil more so that the first or second chambers B ₁ and B ₂ do not become vacuum.

That is, when the pressure in the _first and second chambers B ₁ and B ₂ (hereinafter referred to as load pressure) based on the load F acting on the actuator B is higher than the discharge pressure of the hydraulic pressure source P, the actuator B
In some cases, the pressure oil flows backward to the hydraulic pressure source P side, and this backflow is prevented by the check valve 8.

Further, the actuator B moves at a speed higher than the speed based on the amount of the pressure oil supplied from the hydraulic pressure source P by the load F. In this case, the chamber on the side to which the pressure oil is supplied is evacuated. Therefore, in this case, the vacuum prevention valve 9 is opened to communicate the tank port 10 with the first or second outlet port 6, 7 to suck oil from the tank 11 so that no vacuum is generated.

[Problems to be solved by the invention]

In such an operation valve device, the check valve 8 and the vacuum prevention valve 9 are biaxially arranged in parallel between the inlet port 2 and the first and second outlet ports 6, 7. Since the distance between the inlet port 2 and the first and second outlet ports 6, 7 becomes longer and the valve body 1 becomes larger, the whole device becomes larger.

Further, since the vacuum prevention valve 9 is located on the outlet port side, when the sheet is defective or foreign matter is caught, the pressure oil flows from the tank port 10 to the tank 11, and the oil leakage increases, and the actuator B cannot be held. Or operation becomes slow.

Accordingly, it is an object of the present invention to provide an operation valve device capable of reducing the space to make the entire device compact and reducing oil leakage from the vacuum check valve.

[Means and actions for solving the problems]

An operation valve device according to the present invention includes a valve body having an oil hole communicating an inlet port and an outlet port, a tank port adjacent to the oil hole, and a communication hole communicating the tank port with the oil hole. The check valve 16 is pushed to the position where the oil hole is closed by the spring force and the pressure of the outlet port provided in the main body, and is pushed to the position where the oil hole is opened by the pressure of the inlet port. It is provided on the same axis as the valve 16 and is pushed to the position to close the communication hole by spring force and inlet port pressure,
An operation valve device comprising a valve for a vacuum prevention valve 19 which is pushed to a position where a communication hole is opened by pressure of a tank port.

According to the operation valve device of the present invention, when the load pressure of the actuator is high, the load pressure acts on the outlet port and pushes the check valve 16 to the closed position, so that the pressure oil of the actuator is discharged from the outlet port. No more backflow to the inlet port. In addition, the check valve 16 is pushed to the open position by the high pressure oil of the hydraulic source supplied to the inlet port, and the vacuum prevention valve 19 is pushed to the closed position. It can be supplied to the actuator without flowing out.

Also, when a vacuum is generated in one chamber of the actuator, the vacuum prevention valve 19 is pushed to the open position by the pressure of the tank port, so that the pressure oil of the tank port 10 flows from the inlet port to the one chamber of the actuator via the outlet port. Inflow prevents vacuum generation.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to FIG. The same members as those in the related art have the same reference numerals.

The middle of the tank port 10 and the first and second oil holes 3, 4 is the first,
The first and second valve holes 14 and 15 are provided on both sides of the first and second oil holes 3 and 4 in the valve body 1 while communicating with the second communication holes 12 and 13. Drilled concentrically with 13, this first,
The check valve 16 is inserted into the second valve holes 14 and 15, respectively.
The check valve 8 is formed by press-fitting a check valve valve seat 18 with a spring 17, and a vacuum check valve valve 19 is fitted to the small-diameter end portion 16 a of each check valve 16. Valve for check valve
19 is pressed against the valve seat 20 for the vacuum prevention valve by the spring 17 to form the vacuum prevention valve 9.

Thus, when the load pressure of the actuator B is high, the check pressure valve 16 is pressed by the load pressure and presses against the check valve valve seat 18, so that the backflow to the hydraulic power source P side can be prevented. .

Also, the actuator B moves faster than the speed corresponding to the amount of pressure oil supplied from the hydraulic pressure source P, and
When a vacuum is generated in the chambers B ₁ and B ₂ , the check valve 16 and the vacuum check valve 19 move against the spring 17 to move the tank port 10 and the first or second oil holes 6, 7. To prevent the generation of vacuum by sucking pressure oil from the tank 11.

Further, since the check valve valve 16 and the vacuum check valve valve 19 are coaxial, the distance between the inlet port and the outlet port can be shortened to reduce the size of the valve body 1 and the entire apparatus.

In addition, since the check valve 8 is located on the outlet port side, oil leakage from the actuator B is less likely to occur, and the two valves and the valve seat are double-sealed, so that the reliability against dust entrapment is improved. .

The main spool 5 is held at a neutral position by a pair of springs 5a, 5a, and is switched by supplying pilot pressure oil to the pressure receiving chambers 5b, 5b.

As shown in FIG. 2, the holding cylinder 21 is fitted into the first valve hole 14, and the check valve 16 is fitted into the blind hole 21a so that the check valve 16 is held. The valve 19 for a vacuum check valve may slide along the small-diameter end portion 16a as shown in FIG. 3 while sliding along the cylinder 21.

Further, as shown in FIG. 4, the valve 19 for a vacuum check valve may be urged by a spring 22, or as shown in FIG. Hole 1 for valve 16
The spring 23 may be fitted in the inside of 6b.

FIG. 6 shows an application example, in which the first and second oil holes 3 and 4 have the first and second oil holes.
The second outlet ports 6 and 7 are connected to the tank 1 via the two-position two-way valve 30.
In addition to controlling the disconnection to 1, this 2-position 2-way valve 3
0 was held in the blocking position I by a spring 31, so when the pilot pressure oil is supplied becomes communicating position II the pressure receiving chamber 30a, the first discharge pressure oil of the pilot pump P _1, second pilot valve 32, At 33, the pressure is supplied to the pressure receiving chambers 5b and 30a.

Thus, when the first pilot valve 32 is switched by the lever 34, one of the pressure receiving chambers 5b of the main spool 5 is switched.
The pilot pressure oil is supplied to the pressure receiving chamber 30 a of the one-position two-way valve 30, and the main spool 5 connects the inlet port 2 to the second oil hole 4.
To the first position III that communicates with
The direction valve 30 is at the communication position II.

Thereby, the hydraulic source pressure oil discharged of P inlet port 2, a second oil hole 4 is supplied to the second chamber B ₂ of the actuator B from the second outlet port 7, the pressure oil of the first chamber B ₁ is The oil flows out from the first outlet port b, the first oil hole 4 and the two-position two-way valve 30 to the tank 11.

At this time, the pressure oil in the first chamber B ₁ represents prevented from flowing primary spool 5 side by the check valve 8 provided in the first oil hole 3, the pressure oil having flowed into the second oil hole 4 is non-return The valve 8 is pushed open and flows to the second outlet port 7.

In the above-described state, the load F acting on the actuator B is equal to the pressure determined by the set pressure of the main relief valve 35.
When the actuator thrust F ₁ or more based on P _0, the second chamber
The pressure oil in B ₂ may flow through the second oil hole 4 to the hydraulic source P to damage the hydraulic source P. However, the check valve 8 provided in the second oil hole 4 prevents the reverse flow to prevent the reverse flow. It is possible to prevent the hydraulic power source P from being damaged.

Although the actuator B tends to move at a speed greater than the speed based on the oil amount of the hydraulic fluid supplied from the hydraulic pressure source P by the load second chamber B ₂ becomes a negative pressure (vacuum), in this case since reinforced by sucking pressure oil tank 11 from the vacuum prevention valve 9, it is possible to prevent the second chamber B ₂ becomes a negative pressure (vacuum).

〔The invention's effect〕

Since the check valve valve 16 and the vacuum check valve valve 19 are arranged coaxially, the distance between the inlet port and the outlet port is shortened, so that the valve body 1 can be made smaller and the entire apparatus can be made compact. it can.

Also, since the check valve valve 16 and the vacuum check valve valve 19 are coaxial, and each seat is coaxial,
There is a double sheet for oil leakage at the outlet port side, so the amount of oil leakage is reduced, and even if foreign matter bites in one side, it can be sealed with the other, so it is highly reliable against foreign matter intrusion It will be.

[Brief description of the drawings]

1 is a sectional view of a first embodiment of the present invention, FIGS. 2 and 3 are sectional views of a second embodiment, FIGS. 4 and 5 are sectional views of the third and fourth embodiments, FIG. 6 is a circuit diagram of an application example, and FIG. 7 is a sectional view of a conventional example. 1 is a valve body, 2 is an inlet port, 10 is a tank port, 16 is a check valve, and 19 is a vacuum check valve.

Claims (1)

(57) [Claims] 1. A valve body having an oil hole communicating an inlet port and an outlet port, a tank port adjacent to the oil hole, and a communication hole communicating the tank port with the oil hole, provided in the valve body. The check valve 16 is pushed to the position where the oil hole is closed by the spring force and the pressure of the outlet port, and is pushed to the position where the oil hole is opened by the pressure of the inlet port.The valve body is coaxial with the check valve 16. A valve for a vacuum prevention valve 19, which is provided at a position where the communication hole is closed by a spring force and an inlet port pressure and is pressed at a position where the communication hole is opened by the pressure of the tank port. apparatus.