JPH08166077A - Switch valve device - Google Patents

Abstract

PURPOSE: To provide a switch valve device capable of preventing the defective operation and improving the durability of the peripheral equipment by increasing the diameter of a piston rod, and reducing the impact. CONSTITUTION: A switch valve device consists of a first poppet valve 46 which is provided in a circulating passage 7 between a pump to output the high pressure fluid and a tank 2 to release this high pressure fluid, and seats a poppet valve to be in the closing position under the high pressure fluid on a first valve seat 48 of a body 30, and a second poppet valve 51 which is seated on a second valve seat 53 in the first poppet valve 46 and controls the opening/closing of the first poppet valve 46. A shaft part 51B abutted on a piston rod 64 is provided on the second poppet valve 46, and the piston rod 64 is arranged opposite to the second poppet valve 51, and the diameter of the piston rod 64 is increased to the range of the section of the passage to be obtained by opening the first poppet valve 46 capable of securing the required flow rate to release the high pressure fluid.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switching valve device which is provided in a circulation passage for returning a high pressure fluid from a high pressure pump to a tank and connects or disconnects this circulation passage.

[0002]

2. Description of the Related Art A conventional switching valve device of this type is shown in FIG. This device consists of a high pressure pump 1 and a tank 2.
Is provided in the circulation passage 7 between the secondary side device and the secondary side device when the secondary side device is not in use, and the high pressure pump 1 allows the high pressure fluid to escape to the tank 2 when the secondary side device is not used. Is cut off to supply the high-pressure fluid to the secondary device.

The switching valve will be described below. The switching valve device 100 includes an outlet port 10 connected to the tank 2.
2 and an inlet port 105 connected to the high pressure pump 1,
Spherical valve body 10 seated on a valve seat 106 formed on the main body
7 and a piston rod 108 forcibly opening this valve body 107 by the operation of the pilot piston 109. In the switching valve device 100, pilot pressure is supplied to the pilot piston 109 from the directional switching valve 16 via the pilot 17 when the secondary side device is not used, and the piston rod 108 operates to operate the valve body 10 from the inlet port 105 side.
The valve body 107 is forcibly separated from the valve seat 106 against the pressure of the high-pressure fluid acting on 7 and the spring force of the spring 110, and the inlet port 105 and the outlet port 102 are communicated with each other. Further, by eliminating the pilot pressure when the secondary device is used, the high pressure fluid acting on the valve body 107 and the spring force of the spring 110 cause the valve body 107 to be seated on the valve seat 106, and the inlet port 105 and the outlet port 105 The port 102 is shut off.

[0004]

However, in the conventional switching valve device, when the valve body 107 is moved away from the valve seat 106 to open the valve, the inlet port 105
Pressure of the high pressure fluid acting on the valve body 107 from the side and the spring 11
The valve body 107 is provided with a small diameter piston rod 10 against the 0 spring force.
Since it is designed to be separated from the valve seat 106 by 8,
A large load acts on the piston rod 108, and the piston rod 1
There is a problem that the switching valve device 100 may malfunction due to the deformation of 08.

When the valve body 107 of the switching valve device 100 is opened or closed by separating from or seating on the valve seat 106, a large amount of high-pressure fluid flows from the high-pressure pump 103 side through the inlet port 105 at once. Or is shut off, a shock occurs due to the flow or shutoff of this fluid, and vibration and noise are generated by this shock, and peripheral equipment and the switching valve device 1
There is a problem that the durability of the valve body 107 and the valve seat 106 of No. 00 is adversely affected.

The present invention has been made in order to solve such a problem, and reduces the load on the piston rod and reduces the impact to prevent malfunction.
An object of the present invention is to provide a switching valve device capable of improving durability.

[0007]

In order to solve the above problems, in the switching valve device of the present invention, in the first aspect, a circulation passage between the pump for outputting the high pressure fluid and the tank for releasing the high pressure fluid is provided. A poppet valve that is installed and takes a closed position by receiving high-pressure fluid, a pilot piston that receives pilot pressure, and a piston rod that is provided on this pilot piston and that forces the poppet valve to the open position when the pilot pressure is output. In the switching valve device which has the first and second valve seats formed in the main body, the switching valve device has a first valve seat formed in the main body of the switching valve device for disconnecting the circulation passage by the operation of the piston rod.
A second seat for seating on the poppet valve and a second valve seat formed in the first poppet valve to control opening and closing of the first poppet valve.
The second poppet valve is provided with a shaft portion that comes into contact with the piston rod, and the piston rod is opposed to the second poppet valve, so that the passage area obtained by opening the first poppet valve is The diameter of the piston rod is increased to the extent that the required flow rate for releasing the high-pressure fluid can be secured.

According to a second aspect of the present invention, in the switching valve device according to the first aspect, the shaft portion of the second poppet valve restricts the flow of the high pressure fluid until the second poppet valve is in the fully open position. The groove is formed.

According to a third aspect of the present invention, in the switching valve device according to the first or second aspect, the first poppet valve is located at a position facing the first valve seat of the first poppet valve until the first poppet valve is in the fully open position. In the meantime, the throttle portion that restricts the flow of the high-pressure fluid is formed.

[0010]

As described above, according to the switching valve device of the present invention, in claim 1, after the second poppet valve is separated from the second valve seat by the piston rod, the first poppet valve is separated from the first valve seat. When the first poppet is separated from the first valve seat and opened, the diameter of the piston rod is increased to the extent that the passage area obtained by this opening can secure the necessary flow rate for releasing the high pressure fluid. It is possible to reduce the valve opening resistance of the poppet valve, reduce the load on the piston rod, and improve the durability of the piston rod. Further, since the high-pressure fluid does not flow or be interrupted at once, it is possible to reduce the occurrence of impact on the switching valve device itself.

Further, in the present invention, since the throttle groove is formed in the second poppet valve, a small amount of high pressure fluid can escape through the throttle groove until the second poppet valve reaches the fully open position. As a result, a large amount of high-pressure fluid does not flow or shut off at once, so that the impact of the switching valve device itself can be further reduced.

Further, in the present invention, since the throttle portion is formed in the first poppet valve, a small amount of high pressure fluid is allowed to escape through the throttle portion until the first poppet valve is in the fully open position. And a large amount of high-pressure fluid flows at once,
Or, since it is not shut off, it is possible to surely reduce the occurrence of impact on the switching valve device itself in combination with claim 1 or claim 2.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A switching valve device according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view showing a switching valve device according to this embodiment, FIG. 2 (a) is an enlarged sectional view of a throttle portion of the switching valve device in FIG. 1, and FIG. 2 (b) is a switching valve in FIG. 2 (c) is an enlarged view of an essential part showing the configuration of the throttle groove of the device, FIG. 2 (c) is an enlarged view of the essential part showing the configuration of the throttle groove of the switching valve device in FIG. 1, and FIG. FIG. 3A is a graph showing the relationship between the lift amount and the opening area of the second poppet valve, FIG. 3A is an enlarged view of the essential parts showing the operating state of the second poppet valve of the switching valve device of this embodiment, and FIG. It is a principal part enlarged view which shows the operating state of the 1st poppet of the switching valve apparatus of a present Example.

In FIG. 1, reference numeral 30 denotes a main body of the switching valve device 10, which has a cylinder hole 31 opened at one end and a piston hole 32 opened at the other end, respectively. What is hole 32? Communication hole 3
It is connected by 3. Also, at both ends of the main body 30,
The lid members 34, 35 are mounted on the bolt 3 via the seal ring 36.
7 to close the open ends of the cylinder hole 31 and the piston hole 32.

The lid member 35 is formed with a pilot port 39 which opens into the piston hole 32 through a throttle hole 38 and communicates with the piston hole 32. The pilot port 39 supplies and discharges pilot pressure. Is connected to the pilot passage 17.

Further, the main body 30 is formed with an inlet port 41 communicating with the communication hole 33 through the vertical hole 40 and an outlet port 43 communicating with the cylinder hole 31 through the vertical hole 42. 41 is connected to the main passage 6 (high-pressure pump 1) via the circulation passage 7, and the outlet port 43 is connected to the tank 2 via the circulation passage 7.

The cylinder hole 31 is a stepped hole in which a large-diameter hole portion 31A and a small-diameter hole portion 31B are successively reduced in diameter from the opening side toward the communication hole 33, and the large-diameter hole portion 31 is formed.
A sleeve member 44 is fitted in A, and an annular member 45 is fitted in the small-diameter hole portion 31B with a seal ring 45A interposed, and is engaged with the step portion 31a.

A first poppet valve 46 is slidably housed in the cylinder hole 31. The first poppet valve 46 has a sliding portion 46A that is slidably fitted in the sleeve member 44, and a shaft-shaped portion 46B that is reduced in diameter from the sliding portion 46A and extends toward the communication hole 33. , This shaft 46
A conical valve element 47 having a diameter reduced from the B end is seated on a first valve seat 48 formed on the annular member 45. Further, a conical head portion 46C that gradually projects from the valve body 47 of the first poppet valve 46 toward the communication hole 33 side is loosely fitted in the annular member 45, and is shown in FIG. As described above, the narrowed portion 49 is a slight gap (passage of high-pressure fluid) between the outer peripheral surface 46a of the conical head portion 46C and the inner peripheral surface 44a of the annular member 44.
Is formed.

Further, in the first poppet valve 46, a stepped hole in which a spring hole 50A, a communication hole 50B and a shaft hole 50C are continuously formed by gradually reducing the diameter from the end of the sliding portion 46A toward the head portion 46C. 50 is formed, and the second poppet 51 is slidably accommodated in the stepped hole 50. In this second poppet 51, a conical valve body 52 whose diameter is reduced from the main body 51A is seated on a second valve seat 53 formed in a shaft hole 50C of the first poppet valve 46. Communication hole 3
A shaft portion 51B that projects into the shaft 3 and is slidably fitted in the shaft hole 50C of the first poppet 46 is integrally formed.

The shaft portion 51B is provided with throttle grooves 54, 54 extending axially from the end surface. As shown in FIG. 2B, the throttle grooves 54, 54 have a concave cross-section and are formed 180 ° apart from each other in the circumferential direction of the shaft portion 51B. Further, the throttle grooves 54, 54 are shown in FIG.
As shown in (c), it has a groove portion 54A and a taper portion 54B continuous with the groove portion 54A, and the taper portion 54A has a small gap (passage for high-pressure fluid) between itself and the second valve seat 53. 54C is formed.

The first poppet valve 46 has a spring hole 5
The valve body 47 is pressed against the first valve seat 48 by being urged toward the communication hole 33 side by the spring force of the large-diameter valve spring 56 stretched between the step portion of 0 A and the lid member 34. There is. Also, the second
The poppet 51 valve is biased toward the communication hole 33 side by the spring force of a small-diameter valve spring 55 stretched between the end of the main body 51A and the lid member 34, and the valve body 52 is moved to the second valve seat 53. Has been pressed.

The diameter of the piston hole 32 is gradually reduced from the opening side toward the communication hole 33, and the large diameter hole 32A and the small diameter hole 3 are formed.
2B is a continuous stepped hole, and the sleeve member 60 is fitted in the large diameter hole 32A.

A piston 61 is slidably fitted in the sleeve member 60 fitted in the large diameter hole 32A. The piston 61 extends from the main body 63 having a plurality of heads 62A to 62C sliding on the inner peripheral surface of the sleeve material 60 and the main body 63 into the small diameter hole 32B and the communication hole 33,
A piston rod 64 is formed integrally with the shaft portion 51B of the second poppet valve 51 so as to face the shaft portion 51B at a predetermined interval, and the head portion 62C, the sleeve member 60, and the piston hole 3 are formed.
The hydraulic chamber A is defined by the bottom portion 32a of the second valve.

The piston rod 64 of the piston 61 is
When the first poppet 46 separates from the first valve seat 48 and opens, the passage area obtained between the valve body 47 of the first poppet 46 and the first valve seat 48 flows from the input port 41 when the first poppet 46 opens. The diameter is formed in a range that can secure a necessary flow rate for releasing the high-pressure fluid to the outlet port 43.

The piston 61 is urged toward the pilot port 39 by the spring force of a piston spring 65 stretched between the bottom of the small diameter hole 32B and the head 62 of the piston 61, and the end face of the piston 61 is the piston. The bottom 32a of the hole 32 is pressed and engaged. Reference numeral 66 is a lip seal, and 67 is a seal ring, which are externally fitted between the head portions 62A and 62B of the piston 61.

The switching valve device 10 in this embodiment is configured as described above, and the operation of the switching valve device 10 will be described below.

For convenience of explanation, it is assumed that the switching valve device 10 has the first poppet valve 46 seated on the first valve seat 48 and the second poppet valve 51 seated on the second valve seat 53.

(1) First, the high pressure pump 5 is operated to discharge the high pressure fluid into the main passage 6.

(2) As a result, the high-pressure fluid discharged from the high-pressure pump 5 passes through the circulation passage 7 and the switching valve device 10
Into the inlet port 41 of the vertical hole 40-small diameter hole portion 31B
Fill the stepped hole 50 of the first poppet valve 46 through the lateral hole 46 a formed in the first poppet valve 46. In this band, if the secondary device is not in use, the working fluid (for example, oil) is supplied to the pilot port 39 of the switching valve device 10 through the pilot passage 17.

(3) Then, the working fluid flowing into the pilot port 39 of the switching valve device 10 flows into the hydraulic chamber A through the throttle hole 38. As a result, the piston 61 resists the spring force of the piston spring 65 and the second poppet valve 51.
To the side, and finally, the piston rod 64 of the piston 61 comes into contact with the shaft portion 51B of the second poppet valve 51,
The second poppet valve 51 is pressed, and the second poppet valve 51 is moved to the lid member 34 side together with the piston 64 against the spring force of the valve spring 55.

(4) The second poppet valve 51 has the piston 64
At the same time, when the valve body 52 moves away from the second valve seat 53 by moving to the lid member 34 side, as shown in FIG. 3A, the throttle grooves 54, 54 formed in the shaft portion 51B of the poppet 51.
Communicates with the stepped hole 50 of the first poppet valve 46,
The high-pressure fluid filled in the stepped hole 50 has a hollow portion 54B of the throttle groove 54-a throttle portion 54C-a taper portion 54B.
-Through the groove 54A, the communication hole 3 gradually (for each small flow rate)
Inflow into 3. The relationship between the lift amount of the second poppet valve 51 and the opening area at this time is shown in FIG.

(5) Then, the first poppet valve 46 resists the spring force of the valve spring 56 due to the pressure drop in the stepped hole 50 and the differential pressure of the high-pressure fluid from the input port 41 to cause the piston 61 to move. , The lid member 34 together with the second poppet valve 51
Move to the side.

(6) When the first poppet valve 46 starts moving to the lid member 34 side, as shown in FIG.
7 is separated from the first valve seat 48, and the high-pressure fluid becomes
9 gradually flows (at every small flow rate) into the communication hole 33, and finally, the head portion 46C is disengaged from the inside of the annular member 45, and the switching valve device 10 is positioned at the first position 10a. To do.

That is, the first poppet valve 46 moves toward the lid member 34 while gradually increasing the gap between the first poppet valve 46 and the first valve seat 48, but until the head portion 46C comes out of the annular member 45. By the throttle portion 49, a small amount of high-pressure fluid flows from the inlet port 41 into the communication hole 33, and then the head portion 46C of the first poppet 46 comes out of the annular member 45,
The flow rate of the high-pressure fluid flowing from the inlet port 41 to the outlet port 43 increases, and the vertical hole 42-the outlet port 43-
It is returned to the tank 2 through the circulation passage 7.

(7) As a result, the high-pressure fluid sucked and compressed by the high-pressure pump 5 is circulated in the tank 2 through the main passage 6 and the circulation passage 7.

(8) Next, when the high-pressure fluid is supplied to the secondary equipment, the pilot pressure supplied to the hydraulic chamber A of the switching valve device 10 is supplied to the throttle hole 38-output port 39-pilot passage 17. Let it disappear through.

(9) As a result, the piston 61 of the switching valve device 10 is pressed by the spring force of the piston spring 65 until the end face of the piston 61 comes into contact with the bottom portion 32a of the piston hole 32 (until the state shown in FIG. ) It is gradually moved to the lid member 35 side. Then, following the movement of the piston 61, the first poppet valve 46 and the second poppet valve 51 move toward the lid member 35 by the spring force of the valve springs 55 and 56, and the valve body of the first poppet 46. 47 is seated on the first valve seat 48, the valve body 52 of the second poppet valve 51 is seated on the second valve seat 53, and the switching valve device 10 is located at the second position 10b.

(10) When the switching valve device 10 is located at the second position 10b, the high pressure fluid discharged from the high pressure pump 5 for sucking the fluid from the tank 2 is supplied to the secondary side device through the main passage 6. To be done.

As described above, according to the switching valve device of this embodiment, when the switching valve device 10 is opened, after the second poppet valve 51 is separated from the second valve seat 53 by the piston rod 64, The first poppet valve 46 is separated from the first valve seat 48, the first poppet valve 46 is separated from the first valve seat 48, and the high pressure fluid that needs to escape from the inlet port 41 to the outlet port 43 Since the diameter of the piston rod 64 has been increased to the point where the required flow rate can be secured,
The durability of the piston rod 64 is improved, and the switching valve device 1
A malfunction of 0 can be prevented.

Further, in the initial stage of opening the switching valve device 10 (while the second poppet 51 is separated from the second valve seat 53 and the first poppet 46 is separated from the first valve seat 48), the second poppet valve 51 is opened. A small amount of high-pressure fluid can be released from the inlet port 41 to the outlet port 43 through the throttle groove 54 formed in the shaft portion 51B of the shaft and the throttle portion 49 formed in the first poppet, and Inlet port 41 to outlet port 43
Since it does not flow or shut off in a large amount at once, it is possible to reduce the occurrence of impact on the switching valve device 10 itself, and thus it is also possible to reduce the occurrence of vibration and noise due to this impact. Does not adversely affect the durability of the peripheral equipment and the switching valve device 10.

[0042]

As described above, according to the switching valve device of the present invention, when the switching valve device is opened, the second poppet valve is separated from the second valve seat by the piston rod and then the first poppet valve is opened. Is separated from the first valve seat, and
When the first poppet is separated from the first valve seat and opened, the diameter of the piston rod is increased to the extent that the passage area obtained by this opening can secure a necessary flow rate for releasing the high pressure fluid. Since the high pressure fluid can be gradually released by opening the valve to the high pressure fluid and the high pressure fluid will not flow or be interrupted at once, it is possible to reduce the occurrence of impact on the switching valve device itself and to improve the durability of the piston rod. Therefore, it is possible to improve the vibration, and the vibration and noise generated by this impact can be reduced. Therefore, the vibration and noise do not adversely affect the durability of the valve element and the valve seat of the peripheral equipment and the switching valve device. .

Further, since the throttle groove is formed in the second poppet valve, a small amount of high pressure fluid can escape through the throttle groove until the second poppet valve is in the fully open position, so that the high pressure fluid is released. Since a large amount of air will not flow or be shut off all at once, it is possible to reliably reduce the occurrence of impact on the switching valve device itself, and thus to reduce the occurrence of vibration and noise due to this impact. This vibration and noise do not adversely affect the durability of the peripheral device and the valve body and valve seat of the switching valve device.

Further, in the third aspect, since the throttle portion is formed in the first poppet valve, a small flow rate of the high pressure fluid is allowed to escape through the throttle portion until the first poppet valve reaches the fully open position. And a large amount of high-pressure fluid flows at once,
Or, since it will not be shut off, it is possible to reliably reduce the occurrence of impact on the switching valve device itself, and it is also possible to reduce the occurrence of vibration and noise due to this impact, so that this vibration and noise The durability of the valve element and the valve seat of the peripheral equipment and the switching valve device itself is not adversely affected.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a switching valve device according to the present invention.

2A and 2B are views for explaining the details of the switching valve device in FIG. 1, in which FIG. 2A is an enlarged cross-sectional view of a throttle portion, FIG. 2B is an enlarged view of a main portion showing a configuration of a throttle groove, and FIG. 8A is an enlarged view of a main part showing the configuration of the throttle groove, and FIG. 8D is a graph showing the relationship between the lift amount and the opening area of the second poppet valve.

FIG. 3 is an enlarged view of a main part for explaining the operation of the switching valve device of the present invention, in which (a) is a view showing an operating state of the second poppet valve and (b) is an operation of the first poppet valve. It is a figure which shows a state.

FIG. 4 is a cross-sectional view showing a conventional switching valve device.

[Explanation of symbols]

 1 High-pressure pump 2 Tank 7 Circulation passage 10 Switching valve device 41 Inlet port 43 Outlet port 46 First poppet valve 48 First valve seat 49 Throttling portion 51 Second poppet valve 53 Second valve seat 54 Throttling groove 61 Piston 64 Piston rod

Claims (3)

[Claims] 1. A poppet valve, which is provided in a circulation passage between a pump for outputting high-pressure fluid and a tank for releasing this high-pressure fluid, receives the high-pressure fluid and takes a closed position, a pilot piston for receiving pilot pressure, and A switching valve device, which is provided in a pilot piston and has a piston rod forcibly setting the poppet valve to an open position at the time of outputting pilot pressure, and which cuts off the circulation passage by the operation of the piston rod. A first poppet valve seated on a first valve seat formed in the main body and a second poppet valve seated on a second valve seat formed in the first poppet valve and controlling opening and closing of the first poppet valve. The second poppet valve is provided with a shaft portion that comes into contact with the piston rod, and the piston rod is opposed to the second poppet valve. Switching valve device passage area obtained by the opening of which is characterized in that the large diameter of the piston rod to a range that can ensure the necessary flow to escape the high pressure fluid. 2. The shaft portion of the second poppet valve, the second
2. The switching valve device according to claim 1, wherein a throttle groove for restricting the flow of the high-pressure fluid is formed until the poppet valve reaches the fully open position. 3. A throttle portion, which restricts the flow of high-pressure fluid, is formed at a position of the first poppet valve facing the first valve seat until the first poppet valve is in the fully open position. The switching valve device according to claim 1 or claim 2.