JPH0224965Y2 - - Google Patents

Description

[Detailed explanation of the idea] <Industrial application field> The present invention relates to a flow divider valve.

<Prior Art> Conventionally, a pressure fluid diversion valve divides pressure fluid from a pump into a control flow and a surplus flow, and its known structure includes the following.

For example, the device described in Japanese Patent Publication No. 51-13256 sends an appropriate amount of pressure fluid to the sub-division side when it is in a working state, and when it is in a non-working state, the fluid flow rate is extremely small. A sub-diversion hole consisting of a small-diameter hole and a large-diameter hole is bored in the body wall of the spool, and the large-diameter hole slides to open and close in proportion to the pressure level of the sub-division passage. A piston-type controller is housed inside the spool, and the small diameter hole has a normally open structure.

<Problems to be solved by the invention> However, in the above conventional technology, when the pressure on the sub-division side becomes too high in the working state and reaches the relief pressure,
A built-in relief valve works and the controlled flow drains into the tank. At this time, the control element opens the large diameter hole due to the high pressure on the sub-division side, so the control flow flows through the small diameter hole and the large diameter hole, causing the entire flow rate of the control flow to drain into the tank. There was a problem.

In view of the above, an object of the present invention is to provide a flow divider valve that saves energy by switching the flow rate controlled during operation of the relief valve to a smaller flow rate to minimize flow loss.

<Means for solving the problem> As shown in FIG. An outlet hole 15 is formed, a hollow main spool 2 is slidably fitted into the valve body 1, and a plunger 3 and a relief spool 4 are successively and slidably fitted into the main spool 2, To the plunger 3,
A first orifice 7 with a small diameter and a second orifice 8 with a large diameter are formed to communicate the pressure fluid inlet hole 5 and the control outlet hole 6. When the pressure of the control flow reaches the relief pressure, the relief spool 4 slides to open and close the second orifice 8 in proportion to the pressure of the control flow. The operating pressure P _p of the plunger 3 is set to be lower than the operating pressure PR of the relief spool 4, and the relief spool 4 and the plunger reach the relief operating pressure. When the control outlet hole 6 and the relief outlet hole 9 are connected to each other, the plunger 3 is slid to close the second orifice 8.

<Operation> In the above problem solving means, the pressure fluid sent from the pump 11 reaches the pressure chamber 22 of the main spool 2 from the inlet hole 5, and moves the main spool 2 to the right. As a result, the pressure fluid is sent from the surplus outlet hole 15 to the actuator 18 .

On the other hand, when the control outlet hole 6 side is in a non-operating state, the left chamber 25 of the plunger 3 communicating with the outlet hole 6
The pressure at a is low, the plunger 3 is in the left position due to the compression spring 28, and the second orifice 8 is closed. Therefore, the pressure fluid sent from the inlet hole 5 flows from the small diameter first orifice 7 of the plunger 3 to the outlet hole 6.

Next, as shown in FIG. 1, the switching valve 36 on the outlet hole 6 side
etc. are switched to the operating state, the circuit pressure in the outlet hole 6 increases. Then, the left chamber 25a of the plunger 3 communicating therewith becomes in a high pressure state, and the plunger 3 is moved to the right by a distance L1 or more against the elastic force of the compression spring 28, and the second orifice 8 is opened. Therefore, the control flow becomes the combined flow rate of the first orifice 7 and the second orifice 8 as shown in FIG. 2, and the flow rate increases.

In this way, the controlled flow can be supplied to the controlled outlet hole 6 in an appropriate amount depending on the operating state of the controlled outlet hole.

Here, the control flow becomes high pressure for some reason,
When the relief operating pressure as shown in FIG. 2 is reached, the relief pressure chamber 30 communicating with the control outlet hole 6 becomes high pressure, and the relief spool 4 is moved to the left against the elastic force of the compression spring 29. Therefore, the relief spool 4 moves the plunger 3 to the left to close the second orifice 8 and limit the control flow supplied to the control outlet hole 6.

Then, when the relief spool 4 moves to the left by a dimension L3 or more, the control outlet hole 6 and the relief outlet hole 9 are communicated with each other, and water is drained into the tank.

In this way, the plunger 3 moves to the left and closes the second orifice 8 before the controlled flow drains into the tank from the relief outlet hole 9, so the flow loss to the tank during relief can be minimized. .

<Embodiment> Hereinafter, the present invention will be explained based on the embodiment shown in FIG. 1. The diverter valve of the present invention includes a valve body 1 which is hollow and which is closed at both ends, and a main spool 2 which is hollow and which is closed at both ends. A plunger 3 and a relief spool 4, each having an open left end and a closed right end, are successively fitted into the main spool 2 so as to be slidable therein.

The plunger 3 is provided with a first orifice 7 of a small diameter and a second orifice 8 of a large diameter, which communicate the pressure fluid inlet hole 5 and the control outlet hole 6 provided in the valve body 1.

The relief spool 4 is provided with a relief passage 10 so as to communicate between the control outlet hole 6 and the relief outlet hole 9 provided in the valve body 1 when the pressure of the control flow exceeds a certain level (relief operating pressure or higher). ing.

The pressure fluid inlet hole 5 is connected to the pump 11 via a conduit 12 and communicates with a first annular groove 13 formed on the outer periphery of the main spool 2 . The valve body 1 has a surplus outlet groove 14 which communicates with the first annular groove 13 by movement of the main spool 2.
A surplus outlet hole 15 is formed near the first annular groove 13. The surplus outlet hole 15 is connected to the conduit 16
An actuator 18 is connected via a control valve 17.

A second annular groove 20 is formed in the main spool 2 to guide the controlled flow from the controlled outlet hole 5 to the orifices 7 and 8 of the plunger 3. A large diameter main passage 23 that communicates the second annular groove 20 and the first annular groove 13 is formed in the valve body 1. Further, a small diameter passage 21 that communicates the second annular groove 20 with the pressure chamber 22 on the left side of the main spool 2 is formed in the valve body 1 . And main spool 2 is
It is biased to the left by the compression spring 19, and its biasing force is balanced with the pressure of the pressure fluid introduced into the pressure chamber 22.

The main spool 2 also has a second annular groove 20.
A passage 25 is provided that communicates between the main spool 2 and a third annular groove 24 provided on the inner periphery of the main spool 2.

The first orifice 7 and the second orifice 8 are
The third annular groove 24 and the left chamber 25a of the plunger 3 are communicated with each other.

A passage 26 for communicating the left chamber 25a and the control outlet hole 6 is formed in the plunger 3,
A passage 27 formed in the main spool 2 communicates the passage 26 with the control outlet 6. The plunger 3 is biased leftward by the compression spring 28, so that the second orifice 8 is located on the inner peripheral wall of the main spool 2 in the low pressure state of the left chamber 25a, and the first orifice 8 is located on the third annular groove 25. It is set to communicate with.

The relief spool 4 is biased to the right by the compression spring 29, and a passage 31 is provided in the valve body 1 that communicates the relief pressure chamber 30 on the right side with the control outlet hole 6.

Further, as the relief spool 4 moves to the left, the passages 40 and 41 that communicate the relief passage 10 of the relief spool 4 and the control outlet hole 6,
They are formed on the valve body 1 and the main spool 2, respectively. Further, a passage 35 is formed in the main spool 2, which communicates the relief chamber 34 on the left side of the relief spool 4 with the relief outlet hole 9 of the valve body 1.

In addition, main spool 2 and relief spool 4
A compression spring 29 is interposed between the pressure spring 29 and the pressure spring 29 to balance the pressure in the relief pressure chamber 30.

In addition, in the figure, 36 is a switching valve, and 37 is a booster. The switching valve 36 communicates with the control outlet hole 6 by a conduit 38.

Next, to explain the operation, the pressure fluid (pressure oil) sent from the pump 11 is sent to the pressure fluid inlet hole 5 through the pipe line. This pressure fluid flows through the first annular groove 1
3. It is sent from the main passage 23 to the second annular groove 20 and further passes through the passage 21 to reach the pressure chamber 22. Therefore, the main spool 2 moves to the right against the elastic force of the compression spring 19, communicating the first annular groove 13 and the surplus outlet groove 14, and the pressurized fluid flows through the surplus outlet hole 15 and the pipe line 16. The signal is sent to the control valve 17 and actuator 18 via the control valve 17 and the actuator 18.

On the other hand, when the control outlet hole 6 side is in a non-operating state, the left chamber 25 of the plunger 3 communicating with the outlet hole 6
The pressure at a is low, the plunger 3 is in the left position due to the compression spring 28, and the second orifice 8 is closed. Therefore, the pressure fluid sent from the pressure fluid inlet hole 5 to the second annular groove 20 passes from the small-diameter first orifice 7 of the plunger 3 through the left chamber 25a, the passage 26 and the passage 27, and enters the control outlet hole. 6
flows to

Next, the switching valve 36 switches the booster 37
When the valve is activated, the circuit pressure of the control outlet hole 6 increases. Then, the left ventricle 25 of plunger 3
a becomes in a high pressure state, and the plunger 3 is moved to the right by a distance L1 or more against the elastic force of the compression spring 26, and the second orifice 8 is opened. Therefore, the control flow becomes the combined flow rate of the first orifice 7 and the second orifice 8 as shown in FIG. 2, and the flow rate increases.

In this way, an appropriate amount of the control flow can be supplied to the control outlet hole depending on the operating state of the control outlet hole.

Here, the control flow becomes high pressure for some reason,
When the relief operating pressure as shown in FIG. 2 is reached, the pressure in the relief pressure chamber 30 communicating with the control outlet hole 6 becomes high, and the relief spool 4 is moved to the left against the elastic force of the compression spring 29. Therefore, the relief spool 4 comes into contact with the right end 3a of the plunger 3, moves the plunger 3 to the left, closes the second orifice 8, and limits the control flow supplied to the control outlet hole 6.

If the relief spool 4 moves to the left by a dimension L3 or more due to the pressure in the relief pressure chamber 30, the control outlet hole 6 communicates with the relief passage 10 via the passages 40 and 41, so that the control of the outlet hole 6 can be controlled. Flow drains from the relief passage 10 through the relief chamber 34, the passage 35 and the relief outlet hole 9 into the tank.

Therefore, before the controlled flow drains into the tank from the relief outlet hole 9, the plunger 3 moves to the left and closes the second orifice 8, so that the flow loss to the tank during relief can be minimized. .

In the above description, since the relief spool 4 is provided to protect the circuit, the following relationship exists between the operating pressure Pp of the plunger 3 and the operating pressure PR of the relief spool 4.

Pp<PR However, Pp: plunger working pressure (merging pressure) PR: relief spool working pressure (relief pressure) However, before the control flow is drained from the relief outlet hole 9 to the tank, the plunger 3 must be moved to the left. In order for the second orifice 8 to close, the plunger 3 must start moving before the relief spool 4.

That is, the following conditions may be satisfied.

(a) When the circuit pressure P of the control flow outlet hole 6 is lower than that of the plunger 3
P≦Pp A ₁ ×P≦Fp＋kp×δp (max L ₁ ) A ₂ ×P＜Fp＋kp×δp (max L ₁ )＋FR However, A ₁ : Disconnection of plunger 3 Area A ₂ : Cross-sectional area P of the relief spool 4: Circuit pressure Fp of the control outlet hole 6: Load kp of the spring 28 when set: Spring constant δp of the spring 28: Deflection amount FR of the spring 28: Setting load A of the spring 29 ₁ <A ₂ (b) Range from when circuit pressure P exceeds confluence pressure Pp to relief pressure PR Pp<P≦PR A ₂ ×P≦A ₁ ×P+FR+kR×L _3However , kR: Spring constant of spring 29 Effects of the invention> As is clear from the above explanation, the present invention is configured so that the controlled flow can be automatically switched into two stages: a controlled flow by the first orifice and a combined controlled flow by the first and second orifices. In addition, since only the first orifice is configured to open during relief, it is possible to provide an efficient flow divider valve that does not generate wasteful flow unlike conventional methods and can limit flow loss to a minimum. It has excellent effects.

[Brief explanation of the drawing]

FIG. 1 shows a sectional view and a fluid pressure circuit diagram of a flow dividing valve according to an embodiment of the present invention, and FIGS. 2 and 3 are diagrams for explaining the operation of the present invention. 1: Valve body, 2: Main spool, 3: Plunger, 4: Relief spool, 5: Pressure fluid inlet hole, 6: Control outlet hole, 7: First orifice,
8: Second orifice, 9: Relief exit hole, 1
0: Relief passage.

Claims (1)

[Scope of utility model registration request] A hollow valve body 1 has a pressure fluid inlet hole 5, a control outlet hole 6, a relief outlet hole and a surplus outlet hole 1.
5 is formed, a hollow main spool 2 is slidably fitted into the valve body 1, a plunger 3 and a relief spool 4 are slidably and successively fitted into the main spool 2, and the plunger 3, a small-diameter first orifice 7 communicating with the pressure fluid inlet hole 5 and the control outlet hole 6 is formed with a second orifice 8 having a large diameter, and the plunger 3 controls the pressure of the control outlet hole 6. The relief spool 4 slides to open and close the second orifice 8 in proportion to the high or low of It is configured to communicate with the relief outlet hole 9 of the main body 1, the working pressure P _p of the plunger 3 is set lower than the working pressure PR of the relief spool 4, and the relief spool 4 and the plunger are connected to each other for relief operation. 1. A flow divider valve characterized in that, when pressure is reached, the plunger 3 is slid to close the second orifice 8 before communicating the control outlet hole 6 and the relief outlet hole 9.