JP2009079638A - Pressure control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve workability of a pressure control device without enlarging the device. <P>SOLUTION: A drive piston 22 having a first through hole 25 capable of communicating a pressure reduction port P<SB>2</SB>and a control pressure port P<SB>3</SB>, and an intermediate piston 23 having a first ball valve 29 closable by seating to a first valve seat 26 of the first through hole 25 are provided in a housing 11 having a high pressure port P<SB>1</SB>, the pressure reduction port P<SB>2</SB>and the control pressure port P<SB>3</SB>relatively movably. This device comprises: a first seal member 55 communicating a pressure chamber R<SB>3</SB>communicated with the control pressure port P<SB>3</SB>and blocked on the first valve seat 26 side of the drive piston 22 with a reaction force chamber R<SB>4</SB>blocked on a back side of the drive piston 22 through a communication hole 54, and sealing between the pressure chamber R<SB>3</SB>and the pressure reduction port R<SB>2</SB>at a diameter smaller than that of the pressure chamber P<SB>3</SB>; and a second seal member 56 sealing between a reaction force chamber R<SB>4</SB>and the pressure reduction port P<SB>2</SB>at a diameter smaller than that of the first seal member 55. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a pressure control device that controls a pressure difference by moving a poppet valve with a plunger to connect and block a flow path.

  As a general pressure control device, there is a poppet type solenoid valve. This solenoid valve urges the valve body in one direction by the urging force of a spring, thereby shutting off (or communicating with) the flow path and energizing the solenoid. Then, the flow path is communicated (or blocked) by moving the valve body in the other direction against the urging force of the spring.

  As this solenoid valve, for example, there is one described in Patent Document 1 below.

  The solenoid valve described in Patent Document 1 has an inflow chamber to which an inflow port is connected, an outflow chamber to which an outflow port is connected, and a pressure control chamber to which a pressure control port is connected in order toward the solenoid. A first poppet valve configured by a first valve body disposed in the chamber and a first valve seat that communicates between the inflow chamber and the pressure control chamber when the valve is opened, and is disposed in the pressure control chamber. A second poppet valve is provided that includes a valve body and a second valve seat that can move between a pressure control chamber and an outflow chamber when the valve is opened and is connected to a drive transmission unit of a solenoid. .

JP 2002-295708 A

  In the solenoid valve described in the above-described conventional patent document 1, each poppet valve has a ball as a valve body, a valve seat on which the ball is seated, and a direction in which the ball and the valve seat are seated or separated from each other. It is comprised by the spring to urge. Therefore, to operate the poppet valve, the solenoid is energized, the plunger is moved by the magnetic attractive force, the valve body (ball) is moved, and the communication relationship between the inflow chamber, the pressure control chamber, and the outflow chamber is changed. To do. In this case, by reducing the force with which the plunger presses the valve body (ball), it is necessary to reduce the current supplied to the solenoid and suppress the power consumption.

  Normally, the force that the plunger presses the valve body (ball) is reduced by communicating the outflow chamber in which the plunger is accommodated with the pressure control chamber through a communication path, or by communicating the outflow chamber and the pressure control chamber with the drain. can do. However, in the conventional solenoid valve described above, since each poppet valve is constituted by a pole and a valve seat, there is a problem that the diameter of this portion cannot be reduced and the apparatus is enlarged.

  An object of the present invention is to solve such a problem, and an object of the present invention is to provide a pressure control device that improves operability without increasing the size of the device.

  In order to solve the above-described problems and achieve the object, a pressure control device according to the present invention has a hollow housing having a first port and a second port, and is movably supported in the housing. A drive valve having a first through-hole capable of communicating the first port and the second port, and a first valve seat formed at an end of the first through-hole to seat the first through-hole. A first ball valve that can be closed to shut off the first port and the second port; and a first ball valve that biases the first valve seat of the drive valve away from or closer to the first ball valve. 1 urging means and the first ball valve is seated on the first valve seat by pressing the back side of the first valve seat in the drive valve against the urging force of the first urging means. A pressure control valve comprising a detachable plunger; A first pressure chamber that communicates with the first valve seat side of the drive valve, a second pressure chamber that is partitioned on the back side of the drive valve on the first valve seat side, and the first A communication path communicating the pressure chamber and the second pressure chamber; a first seal member having a smaller diameter than the first pressure chamber and sealing between the first pressure chamber and the first port; and the first seal And a second seal member that seals between the second pressure chamber and the first port with a smaller diameter than the portion.

  In the pressure control device of the present invention, the drive valve includes a first outer diameter portion in which the first valve seat is formed, a second outer diameter portion having a smaller diameter than the first outer diameter portion, and the second outer diameter. A third outer diameter portion having a smaller diameter than the portion, and an opening of the first through hole and the first port is formed between the second outer diameter portion and the third outer diameter portion, The first seal portion is provided in the second outer diameter portion, and the second seal portion is provided in the third outer diameter portion.

  In the pressure control device of the present invention, the second pressure chamber is formed in the housing so as to communicate with the accommodation chamber of the plunger, and the communication passage is formed to communicate with the first pressure chamber and the accommodation chamber. It is said.

  In the pressure control device of the present invention, a pressure reducing port is provided as the first port, a control pressure port is provided as the second port, and the first piston and the second piston move as the drive valve in the housing. The first piston is formed with the first through hole and the first valve seat, the second piston is provided with the first ball valve, and the first piston is The first valve seat is biased and supported in a direction away from the first ball valve by the first biasing means, so that the pressure reducing port and the control pressure port can communicate with each other, and the plunger The pressure reducing port and the control pressure port can be shut off by moving against the biasing force of the first biasing means and seating the first ball valve on the first valve seat.

  In the pressure control device of the present invention, a high pressure port as the first port is provided, and a third piston that is arranged in series along a moving direction of the second piston is disposed as the drive valve in the housing, A second through hole capable of communicating the high pressure port and the control pressure port is formed on the housing side, and a second valve seat is formed at an end of the second through hole, and is seated on the second valve seat. Accordingly, a second ball valve capable of closing the second through hole and blocking the high pressure port and the control pressure port is provided in the third piston, and the third piston is provided by the second urging means. The two-ball valve is biased and supported in the direction in which the two-ball valve is seated on the second valve seat, whereby the high pressure port and the control pressure port can be shut off, and the second piston is biased by the second biasing means. Move against the above 2 is characterized in that the ball valve is capable of communicating the control pressure port and said high pressure port by away from the second valve seat.

  In the pressure control device of the present invention, an external piston that is movable relative to the third piston is disposed in the housing, the second through hole and the second valve seat are formed in the external piston, and the external piston is The high pressure port and the control pressure port can communicate with each other by moving against the urging force of the second urging means and separating the second valve seat from the second ball valve. The pressure reducing port and the control pressure port can be shut off by pressing the second piston against the urging force of the urging means and the first ball valve seating on the first valve seat. It is said.

  According to the pressure control device of the present invention, the housing having the first port and the second port supports the drive valve having the first through hole that can communicate with the first port and the second port in a movable manner, A first ball valve capable of closing the first through hole and blocking the first port and the second port by seating on the first valve seat of one through hole, and separating the first valve seat from the first ball valve A first urging means for urging in the direction or approaching direction, and a plunger capable of seating or separating the first ball valve on the first valve seat by pressing the back side of the drive valve; The first pressure chamber defined on the first valve seat side of the drive valve in communication with the two ports and the second pressure chamber defined on the back side of the first valve seat side of the drive valve are communicated via a communication path. A first seal that is smaller in diameter than the first pressure chamber and seals between the first pressure chamber and the first port. A seal member is provided than the first seal portion and the second pressure chamber with a small diameter and a second sealing member for sealing between the first port. Accordingly, the drive valve is provided with a first seal member having a smaller diameter than the first pressure chamber and a second seal member having a smaller diameter than the first seal portion, and the first pressure chamber and the second pressure chamber are sealed by each seal portion. Therefore, the communication path can be provided without increasing the size of the housing, the apparatus can be prevented from being increased in size, and the first pressure chamber and the second pressure chamber can be communicated with each other through the communication path. It is possible to reduce the pressing force of the drive valve due to the above and improve the operability.

  Hereinafter, embodiments of a pressure control device according to the present invention will be described in detail with reference to the drawings. In addition, this invention is not limited by this Example.

  FIG. 1 is a schematic configuration diagram showing a pressure control device according to an embodiment of the present invention.

  In the poppet type three-way valve as the pressure control device of the present embodiment, as shown in FIG. 1, a housing 11 having a hollow cylindrical shape is composed of an upper housing 12 and a lower housing 13, and a lower portion of the upper housing 12 is By fitting in the lower housing 13, the upper and lower housings 12 and 13 are integrally fixed, and the inside is sealed.

  The housing 11 is formed with a first support hole 14 penetrating along the vertical direction at the center thereof. An attachment hole 15 that communicates with the first support hole 14 and has a larger diameter than the first support hole 14 is formed at the upper end of the housing 11, and has a larger diameter than the attachment hole 15. A hole 16 is formed, and the upper part opens to the outside. The position adjusting disk 17 has a threaded portion 17a formed on the outer peripheral portion, and an annular mounting portion 17b that projects downward from the threaded portion 17a. The position adjusting disk 17 has an outer peripheral surface of the annular portion 17b fitted into the mounting hole 15 of the housing 11 through the seal member 18, and a screw portion 17a is screwed into the screw hole 16. The opening above the first support hole 14 is closed by the disk 17.

  In addition, a second support hole 19 that communicates with the first support hole 14 and has a smaller diameter than the first support hole 14 is formed in the lower portion of the housing 11, and a smaller diameter than the second support hole 19. A third support hole 20 is formed, and the third support hole 20 communicates with the storage chamber 21.

  A drive piston (first piston) 22 constituting a drive valve is movably fitted over the first support hole 14, the second support hole 19, and the third support hole 20 of the housing 11. An intermediate piston (second piston) 23 that constitutes a drive valve is movably fitted in the first support hole 14 of the housing 11. The drive piston 22 and the intermediate piston 23 are arranged in series along the axial direction of the support holes 14, 19, 20.

  The drive piston 22 has a cylindrical shape, a disc shape, and a first outer diameter portion 24a fitted into the first support hole 14, and a second support hole 19 having a smaller diameter than the first outer diameter portion 24a. A second outer diameter portion 24b that fits into the second outer diameter portion 24c and a third outer diameter portion 24c that has a smaller diameter than the second outer diameter portion 24b and fits into the third support hole 20 are integrally formed. Further, the drive piston 22 is formed with a hole 25a along the axial direction and a hole 25b that intersects the hole 25a along the radial direction, and the two holes 25a and 25b make the first penetration. A hole 25 is formed. A first valve seat 26 having a conical shape is formed at the upper end of the first through hole 25.

  The intermediate piston 23 has a columnar shape, has a disk shape and is fitted into the first support hole 14, and a second outer diameter portion 28 having a smaller diameter than the first outer diameter portion 27. Are integrally formed. The intermediate piston 23 has a recess 23a formed at the lower end thereof, and a first ball valve 29 is mounted on the recess 23a. The first ball valve 29 is attached to the first valve seat 26 of the drive piston 22. It can be seated. Further, the intermediate piston 23 is formed with a pressing portion 30 protruding from the upper end portion.

  A return spring (first biasing means) 31 is interposed between the first outer diameter portion 24a of the drive piston 22 and the first outer diameter portion 27 of the intermediate piston 23, and due to the biasing force. By urging and supporting the drive piston 22 and the intermediate piston 23 in a direction away from each other, the first ball valve 29 is separated from the first valve seat 26 and the first through hole 25 is opened.

  The housing chamber 21 described above is provided in the lower portion of the housing 11, and a plunger 32 is supported in the housing chamber 21 so as to be movable in the vertical direction. A rod portion extending upward from the plunger 32 is provided. 32a is movably fitted in the third support hole 20, and the tip is in contact with the back surface of the first valve seat 26 in the drive piston 22, that is, the lower surface of the third outer diameter portion 24c. A coil 33 covered with the lower housing 13 is wound around the outer periphery of the plunger 32. In this case, the plunger 32 and the coil 33 constitute a solenoid.

  Accordingly, the drive piston 22 is urged downward by the urging force of the return spring 31, the first outer diameter portion 24a abuts against the step portions of the first support hole 14 and the second support hole 19, and the third outer diameter. The lower surface of the portion 24 c is positioned at a position where it abuts on the upper end of the rod portion 32 a of the plunger 32. Then, an electromagnetic force is generated by passing an electric current through the coil 33, and the plunger 32 moves upward by the attraction force, whereby the rod portion 32 a presses the drive piston 22, and the drive piston 22 is connected to the return spring 31. The first through hole 25 can be closed by moving upward against the urging force and seating the first valve seat 26 on the first ball portion 29.

  A cylindrical external piston 34 is movably fitted in the first support hole 14 of the housing 11 and located above the intermediate piston 23, and a pressure constituting a drive valve is formed inside the external piston 34. A control valve (third drive piston) 35 is provided and is movable relative to the external piston 34.

  The external piston 34 has a first outer diameter portion 37 in which a support hole 36 is formed, a guide hole 38 having a smaller diameter than the support hole 36, and a second outer diameter having a smaller diameter than the first outer diameter portion 37. The part 39 is integrally formed and attacked, and the upper part is opened. The outer piston 34 is movably fitted to the inner peripheral surface of the annular portion 17 b of the position adjusting disk 17 via the seal member 40 on the outer peripheral surface of the second outer diameter portion 39. The external piston 34 has a second through hole 41 formed at the lower end portion of the first outer diameter portion 37 and a second valve seat 42 having a conical shape formed at the upper end portion of the second through hole 41. ing.

  The pressure control valve 35 is accommodated in the external piston 34 and is movably fitted in the support hole 36, and a second outer diameter portion 44 having a smaller diameter than the first outer diameter portion 43. A rod portion 45 extending upward from the second outer diameter portion 44 and movably fitted in the guide hole 38 is integrally formed. The pressure control valve 35 is formed with a recess 35 a at the lower end, and a second ball valve 46 is mounted on the recess 35 a, and the second ball valve 46 is a second valve seat 42 of the external piston 34. Can sit on.

  A return spring (second urging means) 48 is interposed between the external piston 34 and the pressure control valve 35 via a seal member 47, and pressure is applied to the external piston 34 by the urging force. By urging and supporting the control valve 35 toward the intermediate piston 23, the second ball valve 46 is seated on the second valve seat 42 and the second through hole 41 is closed. In this case, the external piston 34 is urged and supported upward by the urging force of the return spring 48, and the upper surface of the second outer diameter portion 39 comes into contact with the lower surface of the position adjusting disk 17. The position of is defined. Therefore, by rotating the position adjusting disk 17 with a predetermined tool, the position adjusting disk 17 is moved up and down with respect to the housing 11 to adjust the position (initial position) where the external piston 34 is defined. be able to. The intermediate piston 23 is urged and supported on the side of the external piston 34 and the pressure control valve 35 by the urging force of the return spring 31, and the pressing portion 30 abuts against the second ball valve 46 through the second through hole 41. Yes. In this case, the urging force of the return spring 48 is set to be larger than the urging force of the return spring 31.

As described above, since the drive piston 22, the intermediate piston 23, the external piston 34, and the pressure control valve 35 are movably supported in the housing 11, the pressure control apparatus according to the present embodiment is connected to the external piston 34 and the pressure control device. A high pressure chamber R ₁ defined by the valve 35, a decompression chamber R ₂ defined by the housing 11 and the drive piston 22, and a pressure chamber R ₃ defined by the housing 11 and the intermediate piston 23 are provided.

Then, the high pressure port P ₁ which communicates with the high pressure chamber R ₁ through the upper housing 12 and the external piston 34 is formed, the decompression port P ₂ which communicates with the decompression chamber R ₂ through the upper housing 12 is formed Has been. The control pressure port P ₃ which communicates with the pressure chamber R ₃ through the upper housing 12 is formed. In this case, the high pressure port P ₁ and the pressure reducing port P ₂ function as the first port of the present invention, and the control pressure port P ₃ functions as the second port of the present invention. The high pressure port P ₁ is connected to the high pressure source 51 via the high pressure line L ₁ , the pressure reducing port P ₂ is connected to the reservoir tank 52 via the pressure reducing line L ₂ , and the control pressure port P ₃ is connected to the control line L ₃ . The pressure supply unit 53 is connected.

In this case, since the outer diameter of the pressing portion 30 of the intermediate piston 23 is smaller than the inner diameter of the second through hole 41 of the external piston 34, when the second ball valve 46 is separated from the second valve seat 42, the second through hole 41 opens so that the high pressure chamber R ₁ and the pressure chamber R ₃ can communicate with each other. On the other hand, the second ball valve 46 when seated on the second valve seat 42, high pressure chamber R ₁ and the pressure chamber R ₃ allows blocking the by the second ball valve 46 second through hole 41 is closed. Further, when the first ball valve 29 of the intermediate piston 23 is spaced from the first valve seat 26 of the drive piston 22, the decompression chamber R ₂ and the pressure chamber R ₃ is communicable with the first through hole 25 is opened. On the other hand, the first ball valve 29 when seated on the first valve seat 26, the decompression chamber R ₂ and the pressure chamber R ₃ is capable of interrupting the by the first ball valve 29 in the first through hole 25 is closed.

In this embodiment, the pressure chamber R ₃ as the first pressure chamber that communicates with the control pressure port P ₃ and is partitioned on the first valve seat 26 side in the drive piston 22, and the first valve seat in the drive piston 22. a reaction force chamber R ₄ as a second pressure chamber is provided which is defined on the back side 26 side, and the pressure chamber R ₃ and the reaction force chamber R ₄ are communicated by a communication hole (communication passage) 54 .

That is, the reaction force chamber R ₄ communicates with the accommodation chamber 21 of the plunger 32 through the third support hole 20, the step portions of the first support hole 14 and the second support hole 19 in the pressure chamber R _3, and the accommodation chamber. 21 communicates with the upper surface portion through the communication hole 54. The communication hole 54 is formed in a straight line in the upper housing 12 of the housing 11 in parallel with the support holes 14, 19, 20.

In the drive piston 22, an opening of the first through hole 25 and the decompression chamber R ₂ (decompression port P ₂ ) is formed between the second outer diameter portion 24 b and the third outer diameter portion 24 c. A first seal portion 55 is provided between the second support hole 19 and the second outer diameter portion 24b, and a second seal portion 56 is provided between the third support hole 20 and the third outer diameter portion 24c. Yes. In this case, the first seal portion 55 seals between the pressure chamber R ₃ in diameter than the pressure chamber R ₃ and decompression chamber R ₂ (decompression port P _2). The second seal portion 56 has a smaller diameter than the first seal portion 55 and seals between the pressure chamber R ₃ and the decompression chamber R ₂ (decompression port P ₂ ).

On the other hand, the external pressure chamber R ₅ are partitioned by the upper housing 12 and the external piston 34, through the upper housing 12 and the external pressure port P ₅ communicating with the external pressure chamber R ₅ are formed, the external pressure port P ₅ is connected to an input unit (pressure control unit) 57 via an external pressure line L ₅ . The high pressure port P ₁ communicates with the high pressure chamber R ₁ , and the third seal portion 58 is located above the high pressure port P ₁ between the first support hole 14 and the first outer diameter portion 37. A fourth seal portion 59 is provided below the high pressure port P ₁ . Then, the pressure adjusting chamber R ₆ are partitioned by the upper housing 12 and the external piston 34, the pressure regulating port P ₆ which communicates with the pressure control chamber R ₆ are formed, the pressure regulating port P ₆ is a pressure adjustment line L It is connected to the reservoir tank 52 through ₆ . In this case, the third seal portion 58 seals between the high pressure chamber R ₁ and the pressure adjustment chamber R ₆ . Further, the fourth seal portion 59 seals between the high pressure chamber R ₁ and the pressure chamber R ₃ .

  Therefore, when the coil 33 is not energized, the drive piston 22 is positioned at a position where the lower surface of the third outer diameter portion 24c is in contact with the tip of the rod portion 32a of the plunger 32 by the biasing force of the return spring 31. The first ball valve 29 of the piston 23 is separated from the first valve seat 26 of the drive piston 22 and opens the first through hole 25. At this time, in the pressure control valve 34, the second ball valve 46 is seated on the second valve seat 42 of the external piston 34 by the urging force of the return spring 48, and the second through hole 41 is closed.

  When the coil 33 is energized, the plunger 32 is moved upward by the generated electromagnetic attractive force, the rod portion 32 a presses the third outer diameter portion 24 c of the drive piston 22, and the drive piston 22 is attached to the return spring 31. Moves up against the forces. Then, the first ball valve 29 of the intermediate piston 23 can be seated on the first valve seat 26 of the drive piston 22 and the first through hole 25 can be closed. When the drive piston 22 moves further upward, it moves upward together with the intermediate piston 23, and the pressing portion 30 of the intermediate piston 23 presses the pressure control valve 34 via the second ball valve 46. Then, the pressure control valve 35 moves upward against the urging force of the return spring 48, and the second ball valve 46 can be separated from the second valve seat 42 to open the second through hole 41.

  The housing 11 is supported by a casing (not shown), and a sealing member 60 is interposed between the housing 11 and the casing, so that sealing performance is ensured.

  Here, the pressure control by the pressure control apparatus of the present embodiment described above will be described in detail.

In the pressure control apparatus of the present embodiment, when the coil 33 is in a demagnetized state, the drive piston 22 is biased and supported by the return spring 31 at a position where the first valve seat 26 is separated from the first ball valve 29. On the other hand, the pressure control valve 34 is supported by the biasing force of the return spring 48 so that the second ball valve 46 is seated on the second valve seat 42. Therefore, when the second through hole 41 is closed, the high pressure chamber R ₁ and the pressure chamber R ₃ are shut off, and when the first through hole 25 is opened, the pressure chamber R ₃ and the decompression chamber R ₂ communicate with each other. is doing. As a result, the supply of hydraulic pressure from the high pressure source 51 to the pressure supply unit 53 is stopped.

When the coil 33 is energized from this state, the plunger 32 is moved upward by the generated electromagnetic force to press the drive piston 22, and the drive piston 22 is moved upward against the urging force of the return spring 31. When the drive piston 22 moves upward, first, the first ball valve 29 of the intermediate piston 23 is seated on the first valve seat 26 and the first through hole 25 is closed. Therefore, the communication between the decompression chamber R ₂ and the pressure chamber R ₃ is blocked by closing the first through hole 25.

If the drive piston 22 further moves upward while the drive piston 22 is in contact with the intermediate piston 23, then the pressing portion 30 of the intermediate piston 23 presses the pressure control valve 35 against the biasing force of the return spring 48. The pressure control valve 35 moves upward. When the pressure control valve 35 moves upward, the second ball valve 46 is separated from the second valve seat 42 of the external piston 34 and the second through hole 41 is opened. Therefore, when the second through hole 41 is opened, the high pressure chamber R ₁ and the pressure chamber R ₃ are communicated.

As a result, the pressure acting on the high-pressure chamber R ₁ from the high-pressure source 51 through the high-pressure port P ₁ , that is, high-pressure hydraulic oil passes through the gap between the external piston 34 and the pressure control valve 35 from the high-pressure chamber R ₁ , The fluid flows into the pressure chamber R ₃ through the through hole 41 and is supplied from the control pressure port P ₃ to the pressure supply unit 53 as a control pressure through the control line L ₃ .

At this time, high pressure hydraulic fluid flowing into the high pressure chamber R ₁ through the high-pressure port P ₁ from the high pressure source 51 flows from the high pressure chamber R ₁ in the accommodating chamber 21 through the communicating hole 54, the reaction force chamber through third support holes 20 R _By flowing to ₄ , a hydraulic action is applied to the back side of the drive piston 22. In this case, the drive piston 22 receives hydraulic pressure from the reaction force chamber R ₄ side with respect to the outer diameter (passage area of the second support hole 19) of the second outer diameter portion 24 b on which hydraulic pressure acts from the high pressure chamber R ₁ side. The outer diameter (passage area of the third support hole 20) of the acting third outer diameter portion 24c is set small. Therefore, from the pressure acting on the front side of the drive piston 22 from the high pressure chamber R ₁ side, the drive piston 22 of the drive piston 22 passes through the communication hole 54, the storage chamber 21, the third support hole 20, and the reaction force chamber R ₄ from the high pressure chamber R ₁ side. The pressure acting on the back side increases, and the propulsive force of the plunger 32 that moves due to the electromagnetic force generated by the coil 33 can be reduced.

  When the value of the current supplied to the coil 33 is reduced from this state, the generated electromagnetic force is reduced, the plunger 32 is moved downward, the pressure on the drive piston 22 is reduced, and the drive piston 22 is returned to the return spring. It moves downward by the urging force of 31. Then, while the first ball valve 29 of the intermediate piston 23 is seated on the first valve seat 26 of the drive piston 22 and the first through hole 25 is blocked, the pressure control valve 35 moves downward by the urging force of the return spring 48. Then, the second ball valve 46 is seated on the second valve seat 42 of the external piston 34 to close the second through hole 41. When the drive piston 22 further moves downward, the first valve seat 26 is separated from the first ball valve 29 of the intermediate piston 23 by the urging force of the return spring 31 to open the first through hole 25.

Accordingly, the second ball valve 46 of the pressure control valve 35 is seated on the second valve seat 42 of the external piston 34 and the second through hole 41 is closed, whereby the communication between the high pressure chamber R ₁ and the pressure chamber R ₃ is established. Blocked. On the other hand, the first valve seat 26 of the drive piston 22 by opening the first through hole 25 spaced from the first ball valve 29 of the intermediate piston 23, a decompression chamber R ₂ and the pressure chamber R ₃ communicates. As a result, the control pressure acting on the pressure supply unit 53 from the pressure chamber R ₃ through the control pressure port P ₃ and the control line L ₃ , that is, hydraulic oil passes through the first through hole 25 of the drive piston 22 and the decompression chamber R. ₂ and discharged from the pressure reducing port P ₂ to the reservoir tank 52 through the pressure reducing line L ₂ .

  By the way, when the power supply system and the control system connected to the coil 33 fail, no electromagnetic force is generated even when the coil 33 is energized, and the plunger 32 is moved to move the drive piston 22 and the intermediate piston 23. The hydraulic pressure of the high pressure source 51 cannot be supplied to the pressure supply unit 53.

At this time, in this embodiment, the output from the input unit 57 to the high pressure hydraulic fluid to the external pressure line L _5, by supplying the external pressure port P ₅ to an external pressure chamber R _5, presses the external piston 34 downwardly To do. Then, the external piston 34 and the pressure control valve 35 move downward against the urging force of the return spring 48 and press the intermediate piston 23 via the pressing portion 30. The intermediate piston 23 moves downward against the urging force of the return spring 31 by being pressed by the external piston 34 and the pressure control valve 35. First, the first ball valve 29 is moved to the first piston of the drive piston 22. After the seat 26 is seated and the first through hole 25 is closed, the pressing portion 30 of the intermediate piston 23 presses the second ball valve 46 against the urging force of the return spring 48, and the second ball The valve 46 is separated from the second valve seat 42 of the external piston 34 to open the second through hole 41.

Accordingly, as described above, the first through hole 25 is closed, whereby the communication between the decompression chamber R ₂ and the pressure chamber R ₃ is blocked, while the second through hole 41 is opened, so that the high pressure is increased. The chamber R ₁ and the pressure chamber R ₃ communicate with each other, high pressure hydraulic oil is supplied from the high pressure source 51 to the high pressure chamber R ₁ through the high pressure port P ₁ , flows through the second through hole 41, and flows into the pressure chamber R ₃ . As a control pressure is supplied from the control pressure port P ₃ to the pressure supply unit 53 through the control line L ₃ , the pressure control can be appropriately executed even when the power supply system or the control system fails.

Thus, in the pressure control apparatus of this embodiment, the pressure reducing port P ₂ and the control pressure port P ₃ can be communicated with each other in the housing 11 having the high pressure port P ₁ , the pressure reducing port P ₂ and the control pressure port P _3. A drive piston 22 having a first through-hole 25 and an intermediate piston 23 having a first ball valve 29 that can be closed by being seated on the first valve seat 26 of the first through-hole 25 so as to be relatively movable, The return spring 31 urges the drive piston 22 in a direction in which the first valve seat 26 separates from the first ball valve 29, and presses the back side of the drive piston 22 against the urging force of the return spring 31 to make the first A plunger 32 for seating the first ball valve 29 on the valve seat 26 is provided, and communicates with the control pressure port P ₃ , and is divided into a first pressure chamber (pressure chamber) defined on the first valve seat 26 side of the drive piston 22. and R _3), driving The second pressure chamber partitioned on the back side of the piston 22 communicates by (counterforce chamber R ₄₎ and the communication hole 54, between the pressure chamber R ₃ in diameter than the pressure chamber R ₃ and decompression port P ₂ A first seal member 55 to be sealed and a second seal member 56 having a smaller diameter than the first seal portion 55 and sealing between the reaction force chamber R ₄ and the pressure reducing port P ₂ are provided.

Accordingly, the drive piston 22 is provided with a first seal member 55 having a smaller diameter than the pressure chamber R ₃ and a second seal member 56 having a smaller diameter than the first seal portion 55, and the pressure chamber R ₃ is provided by the seal portions 55 and 56. And the reaction force chamber R ₄ are sealed, the communication hole 54 can be provided without increasing the size of the housing 11, and the increase in size of the apparatus can be suppressed, and the pressure chamber R ₃ and the reaction force chamber can be suppressed. By communicating R ₄ through the communication hole 54, the pressing force of the drive piston 22 by the plunger 32 can be reduced, and the operability can be improved.

In the pressure control device of the present embodiment, the drive piston 22 has a first outer diameter portion 24a in which the first valve seat 26 is formed, a second outer diameter portion 24b having a smaller diameter than the first outer diameter portion 24a, second than the outer diameter 24b provided a third outer diameter portion 24c of the small diameter, the opening of the first through hole 25 and the decompression port P ₂ between the second outer diameter portion 24b and the third outer diameter portion 24c The first seal portion 55 is provided on the second outer diameter portion 24b, and the second seal portion 55 is provided on the third outer diameter portion 24c. Therefore, by making the drive piston 22 a stepped piston, the seal portions 55 and 56 can be easily provided with a simple configuration.

Further, a pressure control device of this embodiment, the counterforce chamber R ₄ communicates with the accommodation chamber 21 of the plunger 32, the communication hole 54 formed in the housing 11 so as to communicate the accommodation chamber 21 and the pressure chamber R ₃ Yes. Therefore, the communication hole 54 can be formed in a straight line, the communication hole 54 can be easily formed, and the enlargement of the housing 11 can be suppressed.

In the pressure control device of this embodiment, the external piston 34 and the pressure control valve 35 are movably supported in the housing 11 so as to face the drive piston 22, and the high pressure port P ₁ and the control pressure port P are connected to the external piston 34. ₃ is provided, and a second ball valve 46 that can be closed by being seated on the second valve seat 42 of the second through hole 41 is provided in the pressure control valve 35. The pressure control valve 35 is urged in the direction in which the second ball valve 46 is seated on the second valve seat 42, and the intermediate piston 23 presses the pressure control valve 34 against the urging force of the return spring 48 to press the pressure control valve 34. The second ball valve 46 can be separated from the seat 42. Therefore, the drive piston 22, the intermediate piston 23, the external piston 34, and the pressure control valve 35 are efficiently accommodated in the housing 11 and supported so as to be movable, so that the structure can be simplified and downsized. In addition, the hydraulic control can be performed with high accuracy.

Further, in the pressure control device of the present embodiment, the external piston 34 is provided facing the drive piston 22, and the external piston 34 is moved by the external pressure, thereby moving the pressure control valve 35 and the intermediate piston 23, and the high pressure chamber. R ₁ can communicate with the pressure chamber R ₃ . Therefore, even if the power supply system or the control system is lost, the intermediate piston 23 is moved by the external piston 34 by supplying the external pressure from the input portion 57 to the external pressure chamber R ₅ , thereby 23, the first ball valve 29 is seated on the first valve seat 26 of the drive piston 22 to close the first through hole 25, and the pressure control valve 35 is moved by the intermediate piston 23. apart two ball valve 46 from the second valve seat 42 of the external piston 34 can open the second through hole 41 reliably by supplying hydraulic oil in the high pressure chamber R ₁ to the pressure chamber R ₃ controlled pressure Can be supplied to the pressure supply unit 53. As a result, it is possible to appropriately control the pressure without using a separate switching mechanism or the like.

In the above-described embodiment, the drive piston 22 is formed with the first through hole 25 that allows the pressure reducing port P ₂ and the control pressure port P ₃ to communicate with each other, and the intermediate piston 23 has the first valve seat 26 of the first through hole 25. A first ball valve 29 that is seated and closed is provided, and a return spring 31 biases the first valve seat 26 of the drive piston 22 away from the first ball valve 29, while the external piston 34 has a high-pressure port P. ₁ and the control pressure port P ₃ are formed, a second through hole 41 is formed, and the pressure control valve 35 is provided with a second ball valve 46 that is seated on the second valve seat 42 of the second through hole 41 and closed. The return spring 48 is configured to urge the second ball valve 46 of the pressure control valve 35 in the direction in which the second ball valve 46 is seated on the second valve seat 42, but is not limited to this configuration. That is, the drive piston has a second through hole that allows the high pressure port and the control pressure port to communicate with each other, and the intermediate piston has a second ball valve that sits on the second valve seat of the second through hole and closes, and a return spring. As a result, the second ball valve of the drive piston is urged in the direction in which the second piston is seated on the second valve seat, while the first piston is formed in the external piston so that the pressure reducing port and the control pressure port can communicate with each other. A first ball valve that is seated and closed on the first valve seat of the through hole may be provided, and the first valve seat may be biased in a direction away from the first ball valve of the pressure control valve by a return spring. Good.

  As described above, the pressure control device according to the present invention improves operability without increasing the size of the device, and is suitable for use in any type of pressure control device.

FIG. 1 is a schematic configuration diagram showing a pressure control device according to an embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Housing 14 1st support hole 19 2nd support hole 20 3rd support hole 21 Storage chamber 22 Drive piston (drive valve)
23 Intermediate piston (drive valve)
24a First outer diameter portion 24b Second outer diameter portion 24c Third outer diameter portion 25 First through hole 26 First valve seat 29 First ball valve 31 Return spring (first biasing means)
32 Plunger 33 Coil 34 External piston 35 Pressure control valve (drive valve)
41 Second through hole 42 Second valve seat 46 Second ball valve 48 Return spring (second urging means)
51 High-pressure source 52 Reservoir tank 53 Pressure supply part 54 Communication hole (communication path)
55 1st seal member (1st seal part)
56 Second seal member (second seal part)
57 Input section R ₁ high pressure chamber R ₂ decompression chamber R ₃ pressure chamber (first pressure chamber)
R ₄ reaction force chamber (second pressure chamber)
R ₅ External pressure chamber R ₆ Pressure adjustment chamber P ₁ High pressure port (first port)
P ₂ decompression port (first port)
P ₃ control pressure port (second port)
P ₄ reaction force port P ₅ external pressure port P ₆ pressure adjustment port

Claims (6)

  A housing having a hollow shape and having a first port and a second port, and a drive valve having a first through hole that is movably supported in the housing and can communicate with the first port and the second port; A first ball valve capable of closing the first through hole and shutting off the first port and the second port by being seated on a first valve seat formed at an end of the first through hole; A first urging means for urging the first valve seat of the driving valve in a direction away from or approaching the first ball valve; and the driving valve against the urging force of the first urging means. In the pressure control valve comprising a plunger capable of seating or separating the first ball valve on the first valve seat by pressing the back side of the first valve seat in the valve, the drive in communication with the second port A first pressure chamber defined on the first valve seat side of the valve; A second pressure chamber defined on the back side of the first valve seat side in the drive valve, a communication path communicating the first pressure chamber and the second pressure chamber, and a smaller diameter than the first pressure chamber. A first seal member that seals between the first pressure chamber and the first port; and a second seal that seals between the second pressure chamber and the first port with a smaller diameter than the first seal portion. And a pressure control device.   The drive valve includes a first outer diameter portion in which the first valve seat is formed, a second outer diameter portion having a smaller diameter than the first outer diameter portion, and a third outer diameter having a smaller diameter than the second outer diameter portion. An opening of the first through hole and the first port is formed between the second outer diameter portion and the third outer diameter portion, and the second outer diameter portion includes the first outer diameter portion. The pressure control device according to claim 1, wherein one seal portion is provided, and the second seal portion is provided in the third outer diameter portion.   The said 2nd pressure chamber is connected to the storage chamber of the said plunger, and the said communication path is formed in the said housing so that the said 1st pressure chamber and the said storage chamber may be connected. The pressure control apparatus as described.   A pressure reducing port is provided as the first port, a control pressure port is provided as the second port, and a first piston and a second piston are arranged in series along the moving direction as the drive valve in the housing. The first piston is formed with the first through hole and the first valve seat, the second piston is provided with the first ball valve, and the first piston is moved by the first biasing means. The first valve seat is urged and supported in a direction away from the first ball valve, so that the pressure reducing port and the control pressure port can communicate with each other, and the urging force of the first urging means by the plunger. 4. The pressure reducing port and the control pressure port can be shut off by moving against the pressure and seating the first ball valve on the first valve seat. Suddenly The pressure control system of the mounting.   A high pressure port as the first port is provided, and a third piston in series along the moving direction of the second piston is disposed as the drive valve in the housing, and the high pressure port and the A second through hole capable of communicating with the control pressure port is formed, a second valve seat is formed at an end of the second through hole, and the second through hole is formed by being seated on the second valve seat. A second ball valve capable of closing and shutting off the high pressure port and the control pressure port is provided on the third piston, and the third piston is configured such that the second ball valve is connected to the second valve by a second urging means. The high pressure port and the control pressure port can be shut off by being urged and supported in the direction of seating on the seat, and the second piston moves against the urging force of the second urging means by the second piston. The second ball valve is the second valve seat The pressure control device according to claim 4, characterized in that by al spaced a can communicate with the control pressure port and said high pressure port.   An external piston that is movable relative to the third piston is disposed in the housing, the second through hole and the second valve seat are formed in the external piston, and the external piston is formed by the second urging means. The high pressure port and the control pressure port can communicate with each other by moving against the urging force and the second valve seat being separated from the second ball valve, and resisting the urging force of the first urging means. 6. The pressure reducing port and the control pressure port can be shut off by pressing the second piston and the first ball valve seating on the first valve seat. Pressure control device.

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