JP7033563B2 - Switching valve - Google Patents

Description

The present invention relates to a switching valve.

For example, in Patent Document 1, a so-called double-seat valve type switching valve including a first valve body that can be connected to and detached from the first valve seat and a second valve body that can be attached to and detached from the second valve seat is provided. Is disclosed. The first valve body and the second valve body are configured to be integrally movable in the axial direction of the body in the cylindrical body. The first valve seat and the second valve seat face in the same direction in the axial direction of the body. The first valve body and the second valve body are urged by a valve spring in a direction approaching each of the first valve seat and the second valve seat. Then, the first valve body and the second valve body move integrally with respect to each of the first valve seat and the second valve seat against the urging force of the valve spring, so that the first valve body and the second valve body first move. A fluid flow between the valve body and the first valve seat is allowed, and a fluid flow between the second valve body and the second valve seat is allowed. According to this, it is possible to secure a large flow rate as compared with the so-called single-seat valve type switching valve in which only one valve body and one valve seat are provided.

Further, it is considered to move the first valve body and the second valve body integrally by using, for example, a piezo actuator as disclosed in Patent Document 2. Some such piezo actuators have a casing that accommodates the piezo element and can expand and contract in accordance with the expansion and contraction of the piezo element. Then, the casing extends against the urging force of the valve spring, so that the first valve body and the second valve body are separated from the first valve seat and the second valve seat, respectively. Such a configuration can obtain higher responsiveness than, for example, a solenoid method using an electromagnetic force and a spring force.

Japanese Unexamined Patent Publication No. 2007-218354 Japanese Unexamined Patent Publication No. 2004-28138

In such a switching valve, if the positions of the first valve seat and the second valve seat and the position of the casing of the piezo actuator are not adjusted accurately, for example, the casing resists the urging force of the valve spring. The second valve body may still be seated on the second valve seat even though the first valve body is extended and separated from the first valve seat. As described above, when the first valve body and the second valve body are not separated from each of the first valve seat and the second valve seat at the same time, it may be difficult to secure a large flow rate while maintaining high responsiveness. ..

The present invention has been made to solve the above problems, and an object of the present invention is to provide a switching valve capable of ensuring a large flow rate while maintaining high responsiveness.

The switching valve for solving the above problems is provided in the tubular body, the first valve body and the second valve body configured so as to be integrally movable in the axial direction of the body, and in the body. An annular first valve seat to which the first valve body is brought into contact with and detached from the body, and an annular second valve seat provided in the body and to which the second valve body is brought into contact with and detached from the body, and expand and contract in the axial direction of the body. The first valve seat and the second valve seat are provided with a piezo actuator that integrally moves the first valve body and the second valve body as the piezo element expands and contracts, and the first valve seat and the second valve seat are in the axial direction of the body. The first valve body and the second valve body are oriented in the same direction, and the first valve body and the second valve body are urged by a valve spring in a direction approaching each of the first valve seat and the second valve seat, and the piezo actuator is The first valve body and the first valve body and the said The second valve body is a switching valve separated from each of the first valve seat and the second valve seat, and the casing is cylindrical, and the piezo actuator and the first valve body in the body A cylindrical valve seat plug having the first valve seat is arranged between them, the second valve seat is formed on the body, and the valve seat plug is screwed into the inner peripheral surface of the body. A detent portion is provided between the casing and the valve seat plug to regulate the rotation of the casing with respect to the valve seat plug. The plug threaded portion is screwed into the inner peripheral surface of the body via the detent portion, so that the valve seat plug can move in the axial direction against the urging force of the valve spring. The casing is urged by an urging spring in a direction in which the first valve body and the second valve body approach each of the first valve seat and the second valve seat, and the urging in the casing. A cylindrical cover member that regulates movement by the urging force of the spring is screwed into the body, the cover member is screwed into the body, and the casing is subjected to the urging force of the urging spring and the urging force of the spring. It can move in the axial direction of the body integrally with the first valve body and the second valve body against the urging force of the valve spring.

In the switching valve, the casing has an actuator insertion portion inserted into the valve seat plug, and the detent portion has a pair of plug planes formed on a part of the inner peripheral surface of the valve seat plug. It is preferable that the actuator is formed of a pair of actuator planes formed in the actuator insertion portion and capable of contacting the pair of plug planes, respectively.

In the switching valve, it is preferable that the flow path cross-sectional area of the first valve seat and the flow path cross-sectional area of the second valve seat are the same.

According to the present invention, it is possible to secure a large flow rate while maintaining high responsiveness.

FIG. 3 is a sectional view showing a switching valve in an embodiment. Front view of the valve seat plug as seen from the plug protrusion side. Front view of the casing of the piezo actuator from the bottom wall side. Sectional drawing of the switching valve. Sectional drawing for demonstrating the method of positioning a valve seat plug. Sectional drawing for demonstrating the method of positioning a casing.

Hereinafter, an embodiment in which the switching valve is embodied will be described with reference to FIGS. 1 to 6.
As shown in FIG. 1, the switching valve 10 includes a cylindrical body 11. The body 11 has a valve body 12 and a housing 50. The valve body 12 and the housing 50 are cylindrical, respectively. The valve body 12 has a body body 13 and a cap member 14 connected to the body body 13. A valve hole 15 is formed in the body body 13. The valve hole 15 penetrates from one end surface 13a of the body body 13 to the other end surface 13b, which is a surface opposite to the one end surface 13a. The direction in which the valve hole 15 extends is the axial direction of the body 11.

The valve hole 15 has a small diameter hole 15a and a large diameter hole 15b. The small diameter hole 15a and the large diameter hole 15b are each circular holes. The hole diameter of the small diameter hole 15a is smaller than the hole diameter of the large diameter hole 15b. One end of the small diameter hole 15a opens to one end surface 13a of the body body 13, and the other end of the small diameter hole 15a communicates with one end of the large diameter hole 15b. The other end of the large diameter hole 15b is a female screw hole 15c. The female screw hole 15c is open to the other end surface 13b of the body body 13.

A first port 16 is formed in the body body 13. The first port 16 extends in a direction orthogonal to the axial direction of the valve body 12. The first port 16 is arranged at a position overlapping the small diameter hole 15a in the direction orthogonal to the axial direction of the valve body 12 in the body body 13. One end of the first port 16 is open to an outer surface of the body body 13 located in a direction orthogonal to the axial direction of the valve body 12, and is connected to a fluid supply source (not shown) via a pipe or the like. The other end of the first port 16 is arranged at a position separated from the small diameter hole 15a in a direction orthogonal to the axial direction of the valve body 12.

A first connection passage 17 is formed in the body body 13. The first connecting passage 17 extends parallel to the valve hole 15. The first connecting passage 17 crosses the first port 16. Therefore, the first port 16 communicates with the middle of the first connection passage 17. One end of the first connection passage 17 is open to one end surface 13a of the body body 13. The other end of the first connection passage 17 is arranged at a position separated from the large diameter hole 15b in a direction orthogonal to the axial direction of the valve body 12.

A second connection passage 18 is formed in the body body 13. The second connection passage 18 extends in a direction orthogonal to the axial direction of the valve body 12. The second connection passage 18 extends from the outer surface of the body body 13 located in the direction orthogonal to the axial direction of the valve body 12 toward the large diameter hole 15b of the valve hole 15. One end of the second connection passage 18 communicates with the large diameter hole 15b of the valve hole 15. The other end of the second connection passage 18 is closed by the closing member 18a. The middle of the second connecting passage 18 communicates with the other end of the first connecting passage 17.

A second port 19 is formed in the body body 13. The second port 19 extends in a direction orthogonal to the axial direction of the valve body 12. The second port 19 is located on the side opposite to the first port 16 with respect to the small diameter hole 15a of the valve hole 15 in the direction orthogonal to the axial direction of the valve body 12. One end of the second port 19 is open to an outer surface of the body body 13 located in a direction orthogonal to the axial direction of the valve body 12, and is connected to a fluid pressure device (not shown) via a pipe or the like. The other end of the second port 19 communicates with the small diameter hole 15a of the valve hole 15. The switching valve 10 of this embodiment is a 2-port valve.

The cap member 14 is connected to one end surface 13a of the body body 13. A gasket 21 seals between the end surface 14a on the body body 13 side of the cap member 14 and the end surface 13a of the body body 13. A circular hole-shaped recess 22 is formed in the end surface 14a of the cap member 14. The recess 22 communicates with the small diameter hole 15a of the valve hole 15. The hole diameter of the recess 22 is larger than the hole diameter of the small diameter hole 15a and the hole diameter of the large diameter hole 15b. The axis of the inner peripheral surface of the recess 22 coincides with the axis of the small diameter hole 15a. The inner peripheral surface of the small diameter hole 15a, the inner peripheral surface of the large diameter hole 15b, and the inner peripheral surface of the recess 22 form the inner peripheral surface of the body 11.

A third connecting passage 23 is formed in the cap member 14. One end of the third connection passage 23 opens to the end surface 14a of the cap member 14 and communicates with the first connection passage 17. The third connection passage 23 extends in the same direction as the direction in which the first connection passage 17 extends.

A fourth connection passage 24 is formed in the cap member 14. The fourth connecting passage 24 extends in a direction orthogonal to the direction in which the third connecting passage 23 extends. The fourth connection passage 24 extends from the outer surface of the cap member 14 located in the direction orthogonal to the axial direction of the valve body 12 toward the recess 22. One end of the fourth connection passage 24 communicates with the recess 22. The other end of the fourth connection passage 24 is closed by the closing member 24a. The middle of the fourth connecting passage 24 communicates with the other end of the third connecting passage 23.

The switching valve 10 includes a valve seat plug 30. The valve seat plug 30 has a cylindrical shape. The valve seat plug 30 includes a plug insertion portion 31 inserted into the large-diameter hole 15b of the valve hole 15 from the other end surface 13b side of the body body 13, and a plug protrusion 32 protruding from the other end surface 13b of the body body 13. have. The outer diameter of the outer peripheral surface of the plug insertion portion 31 is smaller than the outer diameter of the outer peripheral surface of the plug protruding portion 32. The outer diameter of the outer peripheral surface of the plug insertion portion 31 is slightly smaller than the hole diameter of the large diameter hole 15b.

The valve seat plug 30 has a plug large diameter hole 33, a plug medium diameter hole 34, and a plug small diameter hole 35. The hole diameter of the plug large diameter hole 33 is larger than the hole diameter of the plug medium diameter hole 34 and the hole diameter of the plug small diameter hole 35. The hole diameter of the plug medium diameter hole 34 is larger than the hole diameter of the plug small diameter hole 35. Therefore, the hole diameter of the plug small diameter hole 35 is smaller than the hole diameter of the plug large diameter hole 33 and the hole diameter of the plug medium diameter hole 34.

The plug large-diameter hole 33 is open on the end surface of the plug protrusion 32 on the opposite side of the plug insertion portion 31. The plug medium diameter hole 34 is open on the end surface of the plug insertion portion 31 opposite to the plug protrusion 32. The plug small diameter hole 35 communicates the plug large diameter hole 33 with the plug medium diameter hole 34. The axis of the plug large diameter hole 33, the axis of the plug medium diameter hole 34, and the axis of the plug small diameter hole 35 are the same. The inner peripheral surface of the plug large diameter hole 33, the inner peripheral surface of the plug medium diameter hole 34, and the inner peripheral surface of the plug small diameter hole 35 form the inner peripheral surface of the valve seat plug 30.

As shown in FIG. 2, a part of the inner peripheral surface of the large diameter hole 33 of the plug is a pair of plug planes 33a. Therefore, the pair of plug planes 33a are formed on a part of the inner peripheral surface of the valve seat plug 30. The pair of plug planes 33a extend parallel to each other. The shortest distance between the pair of plug planes 33a is larger than the hole diameter of the plug small diameter hole 35. The shortest distance from the axis of the large diameter hole 33 of the plug to each plug plane 33a is the same.

As shown in FIG. 1, the end portion on the outer peripheral surface of the plug insertion portion 31 on the plug protruding portion 32 side is a plug screw portion 36 on which a male screw is formed. The valve seat plug 30 is attached to the body body 13 by screwing the plug screw portion 36 into the female screw hole 15c. Therefore, the valve seat plug 30 has a plug screw portion 36 screwed into the inner peripheral surface of the body 11.

The plug insertion portion 31 is formed with a communication hole 37 extending in the radial direction of the valve seat plug 30. The communication hole 37 faces the opening portion of the valve hole 15 with respect to the large diameter hole 15b in the second connection passage 18 in a direction orthogonal to the axial direction of the valve body 12. Therefore, the end surface of the plug insertion portion 31 opposite to the plug protrusion 32 is located closer to the small diameter hole 15a of the valve hole 15 than the opening portion of the valve hole 15 with respect to the large diameter hole 15b in the second connection passage 18. There is.

An annular first valve seat 38 is projected from the end surface of the plug insertion portion 31 opposite to the plug protrusion 32. Therefore, the valve seat plug 30 has a first valve seat 38. The first valve seat 38 is arranged in the large diameter hole 15b of the valve hole 15. Therefore, the first valve seat 38 is provided in the body 11. The first valve seat 38 surrounds the plug medium-diameter hole 34 when the end surface of the plug insertion portion 31 opposite to the plug protrusion 32 is viewed in a plan view.

An annular second valve seat 39 is provided so as to project from one end surface 13a of the body body 13. Therefore, the second valve seat 39 is formed on the body 11. The second valve seat 39 is arranged in the recess 22. Therefore, the second valve seat 39 is provided in the body 11. The second valve seat 39 surrounds the small diameter hole 15a of the valve hole 15 when the one end surface 13a of the body body 13 is viewed in a plan view.

The axis of the first valve seat 38 coincides with the axis of the second valve seat 39. The inner diameter of the first valve seat 38 is the same as the inner diameter of the second valve seat 39. Therefore, the flow path cross-sectional area of the first valve seat 38 and the flow path cross-sectional area of the second valve seat 39 are the same. The first valve seat 38 and the second valve seat 39 face in the same direction in the axial direction of the body 11.

The space partitioned by the end surface of the plug insertion portion 31 opposite to the plug protrusion 32 and the large diameter hole 15b of the valve hole 15 is the first valve chamber 41 in which the first valve body 40 is housed. .. Then, the first valve body 40 is brought into contact with and separated from the first valve seat 38. Further, the space partitioned by the one end surface 13a of the body body 13 and the recess 22 is a second valve chamber 43 in which the second valve body 42 is housed. Then, the second valve body 42 is brought into contact with and separated from the second valve seat 39.

The switching valve 10 includes a first valve rod 44 having a first valve body 40 and a second valve rod 45 having a second valve body 42. The first valve rod 44 and the second valve rod 45 are housed in the valve hole 15. The first valve rod 44 and the second valve rod 45 can be integrally moved in the valve hole 15 in the axial direction of the valve body 12.

The first valve rod 44 includes a columnar first shaft portion 44a, an annular first flange portion 44b protruding in the radial direction from the end portion of the outer peripheral surface of the first shaft portion 44a, and the first shaft portion 44a. have. The first shaft portion 44a of the first valve rod 44 is inserted into the plug small diameter hole 35. The outer diameter of the first shaft portion 44a is slightly smaller than the hole diameter of the plug small diameter hole 35. The end of the first shaft portion 44a on the opposite side of the first flange portion 44b can appear and disappear in the large diameter hole 33 of the plug. The inner peripheral surface of the plug small diameter hole 35 is in sliding contact with the outer peripheral surface of the first shaft portion 44a when the first valve rod 44 moves in the axial direction of the valve body 12, and the inner peripheral surface of the valve body 12 in the first valve rod 44 It functions as a guide surface to guide the movement in the axial direction. The end surface of the first shaft portion 44a on the opposite side of the first flange portion 44b is a flat surface.

The first flange portion 44b is housed in the first valve chamber 41. The first valve body 40 is attached to the end surface of the first flange portion 44b on the side of the first shaft portion 44a. The first valve body 40 is an annular rubber member. The outer diameter of the first valve body 40 is the same as the outer diameter of the first flange portion 44b. The end surface of the first flange portion 44b on the opposite side of the first shaft portion 44a and the end surface of the first shaft portion 44a on the first flange portion 44b side are flat surfaces extending in the radial direction of the first shaft portion 44a. It is located on the same plane.

The second valve rod 45 has a columnar second shaft portion 45a and an annular second flange portion 45b protruding in the radial direction of the second shaft portion 45a from the end portion of the second shaft portion 45a. ing. The second shaft portion 45a of the second valve rod 45 is inserted into the small diameter hole 15a of the valve hole 15. The outer diameter of the second shaft portion 45a is 1/3 or less of the hole diameter of the small diameter hole 15a. The end of the second shaft portion 45a on the opposite side of the second flange portion 45b can appear and disappear in the large diameter hole 15b. The end surface of the second shaft portion 45a on the opposite side of the second flange portion 45b is flat. The end surface of the second shaft portion 45a on the opposite side of the second flange portion 45b is in contact with the end surface of the first shaft portion 44a on the first flange portion 44b side in a state of surface contact.

The second flange portion 45b is housed in the recess 22. The second valve body 42 is attached to the end surface of the second flange portion 45b on the second shaft portion 45a side. The second valve body 42 is an annular rubber member. The outer diameter of the second valve body 42 is the same as the outer diameter of the second flange portion 45b. The outer diameter of the first flange portion 44b of the first valve rod 44 is the same as the outer diameter of the second flange portion 45b of the second valve rod 45, and the outer diameter of the first valve body 40 is the second valve body 42. It is the same as the outer diameter of.

A valve spring 46 is housed in the recess 22. The valve spring 46 is interposed between the second flange portion 45b of the second valve rod 45 and the bottom surface of the recess 22. One end of the valve spring 46 is supported by the second flange portion 45b, and the other end of the valve spring 46 is supported by the bottom surface of the recess 22. The valve spring 46 urges the second valve rod 45 in a direction in which the second valve body 42 approaches the second valve seat 39.

The housing 50 is connected to the body body 13 in a state where one end surface 50a of the housing 50 and the other end surface 13b of the body body 13 are abutted against each other. Further, the housing 50 has a cylindrical portion 50f protruding from the other end surface 50b, which is a surface of the housing 50 opposite to the one end surface 50a.

A through hole 51 is formed in the housing 50. The through hole 51 penetrates from one end surface 50a of the housing 50 to the protruding end surface of the cylindrical portion 50f. The direction in which the through hole 51 extends is the axial direction of the housing 50. The axis of the cylindrical portion 50f coincides with the axis of the through hole 51. Further, the axial direction of the housing 50 coincides with the axial direction of the valve body 12.

The through hole 51 has a first hole 51a, a second hole 51b, and a third hole 51c. The first hole 51a, the second hole 51b, and the third hole 51c are each circular holes. The first hole 51a is an end portion of the through hole 51 on the one end surface 50a side of the housing 50, and is open to the one end surface 50a of the housing 50. The second hole 51b is an end portion of the through hole 51 on the protruding end face side of the cylindrical portion 50f of the housing 50, and is open to the protruding end face of the cylindrical portion 50f. The third hole 51c communicates the first hole 51a and the second hole 51b.

The axis of the first hole 51a, the axis of the second hole 51b, and the axis of the third hole 51c are aligned with each other. The axis of the first hole 51a, the axis of the second hole 51b, and the axis of the third hole 51c, that is, the axis of the through hole 51, coincide with the axis of the valve hole 15. The hole diameter of the first hole 51a is the same as the hole diameter of the second hole 51b. The hole diameter of the third hole 51c is smaller than the hole diameter of the first hole 51a and the hole diameter of the second hole 51b. The first hole 51a communicates with the large diameter hole 15b of the valve hole 15. The hole diameter of the first hole 51a is slightly larger than the outer diameter of the plug protrusion 32 of the valve seat plug 30. The plug protrusion 32 protrudes from one end surface 13a of the body body 13 and is arranged in the first hole 51a.

The housing 50 is formed with a set screw hole 50h. The set screw hole 50h extends in a direction orthogonal to the axial direction of the housing 50. One end of the set screw hole 50h is open to the outer surface of the housing 50 located in a direction orthogonal to the axial direction of the housing 50. The other end of the set screw hole 50h communicates with the first hole 51a. A set screw 52 is screwed into the set screw hole 50h. Then, the set screw 52 comes into contact with the outer peripheral surface of the plug protruding portion 32, so that the movement of the body 11 in the valve seat plug 30 in the axial direction is restricted.

The switching valve 10 includes a piezo actuator 60. The piezo actuator 60 is housed in the through hole 51. The piezo actuator 60 has a plurality of piezo elements 61 and a cylindrical casing 62 for accommodating the piezo elements 61. The piezo element 61 has a plate shape. The plurality of piezo elements 61 are laminated in the plate thickness direction to form a piezo stack. The stacking direction of the plurality of piezo elements 61 coincides with the axial direction of the casing 62. The piezo element 61 expands in the plate thickness direction when the piezo element 61 is energized, and when the energization of the piezo element 61 is stopped, the piezo element 61 shrinks and returns to the original shape before the extension.

The casing 62 is a bottomed cylinder having a bottom wall 62a and a cylindrical peripheral wall 62b extending from the outer peripheral edge of the bottom wall 62a. The bottom wall 62a and the peripheral wall 62b are formed of a thin metal plate. The bottom wall 62a has a flat plate shape. Therefore, the outer surface of the bottom wall 62a has a flat surface shape. The portion of the casing 62 on the bottom wall 62a side is an actuator insertion portion 63 that is inserted into the plug large-diameter hole 33 of the valve seat plug 30. Therefore, the casing 62 has an actuator insertion portion 63 that is inserted into the valve seat plug 30. The valve seat plug 30 is arranged between the piezo actuator 60 and the first valve body 40 in the body 11.

When the actuator insertion portion 63 is inserted into the plug large-diameter hole 33 of the valve seat plug 30, the outer surface of the bottom wall 62a of the casing 62 is the end surface of the first shaft portion 44a opposite to the first flange portion 44b. It is in contact with the surface in contact with the surface.

As shown in FIG. 3, a part of the outer peripheral surface of the actuator insertion portion 63 is a pair of actuator planes 64. Therefore, the pair of actuator planes 64 is formed in the actuator insertion portion 63. The pair of actuator planes 64 extend parallel to each other. The shortest distance of the pair of actuator planes 64 is slightly smaller than the shortest distance of the pair of plug planes 33a.

As shown in FIG. 1, the pair of actuator planes 64 can each contact the pair of plug planes 33a. Then, the pair of actuator planes 64 abut against the pair of plug planes 33a, respectively, thereby restricting the rotation of the casing 62 with respect to the valve seat plug 30. Therefore, the pair of plug planes 33a and the pair of actuator planes 64 are provided between the casing 62 and the valve seat plug 30, and form a detent portion 65 that regulates the rotation of the casing 62 with respect to the valve seat plug 30. There is.

The portion of the peripheral wall 62b of the casing 62 other than the actuator insertion portion 63 passes from the inside of the first hole 51a of the through hole 51 through the inside of the third hole 51c and protrudes into the second hole 51b. Most of the portion of the peripheral wall 62b of the casing 62 located in the third hole 51c is a bellows-shaped telescopic portion 62c. An annular flange 62f protruding outward is provided at an end portion of the outer peripheral surface of the peripheral wall 62b opposite to the bottom wall 62a. The flange 62f is located in the second hole 51b of the through hole 51.

The urging spring 66 is housed in the second hole 51b of the through hole 51. The urging spring 66 is interposed between the stepped surface 51e connecting the inner peripheral surface of the second hole 51b and the inner peripheral surface of the third hole 51c and the flange 62f. One end of the urging spring 66 is supported by the stepped surface 51e, and the other end of the urging spring 66 is supported by the flange 62f. The urging spring 66 urges the casing 62 in a direction in which the casing 62 is separated from the valve seat plug 30.

An annular sealing member 67 is disposed between the portion of the inner peripheral surface of the first hole 51a of the through hole 51 closer to the third hole 51c than the valve seat plug 30 and the outer peripheral surface of the peripheral wall 62b of the casing 62. ing. The sealing member 67 seals between the inner peripheral surface of the through hole 51 and the outer peripheral surface of the peripheral wall 62b of the casing 62.

A terminal block 69 having wiring 68 is attached to an opening on the peripheral wall 62b of the casing 62 opposite to the bottom wall 62a. The terminal block 69 is a metal disk-shaped lid member that closes the opening of the peripheral wall 62b. The wiring 68 is drawn out from the end surface 69e located on the side opposite to the peripheral wall 62b of the casing 62 in the terminal block 69. The wiring 68 is connected to a power supply unit (not shown). The piezo actuator 60 is configured to energize a plurality of piezo elements 61 via wiring 68 from the power supply unit.

When the plurality of piezo elements 61 are energized via the wiring 68 from the power supply unit, the plurality of piezo elements 61 are expanded, and the expansion / contraction unit 62c is expanded following the expansion of the plurality of piezo elements 61. It has become. Further, when the energization of the plurality of piezo elements 61 from the power supply unit via the wiring 68 is stopped, the plurality of piezo elements 61 are reduced, and the expansion / contraction unit 62c follows the reduction of the plurality of piezo elements 61. It is designed to shrink. Therefore, the casing 62 can be expanded and contracted following the expansion and contraction of the piezo element 61.

The end surface 69e of the terminal block 69 has a circular shape in a plan view. A jig groove 69a is formed in the central portion of the end surface 69e of the terminal block 69. The jig groove 69a is located on the axis of the casing 62 at the end surface 69e of the terminal block 69.

A male screw 50 g is formed on the outer peripheral surface of the cylindrical portion 50f. A bottomed cylindrical cover member 70 is screwed into the male screw 50 g. Therefore, the cover member 70 is screwed into the body 11. The cover member 70 has a flat plate-shaped cover bottom wall 70a and a cover peripheral wall 70b that protrudes in a cylindrical shape from the outer peripheral portion of the cover bottom wall 70a.

A circular hole-shaped wiring insertion hole 70c is formed in the cover bottom wall 70a. The wiring insertion hole 70c penetrates the cover bottom wall 70a in the thickness direction. The hole diameter of the wiring insertion hole 70c is smaller than the outer diameter of the end surface 69e of the terminal block 69.

On the inner peripheral surface of the cover peripheral wall 70b, a female screw 70 g screwed into the male screw 50 g of the cylindrical portion 50f is formed. Then, the cover member 70 is attached to the cylindrical portion 50f by screwing the female screw 70 g of the cover member 70 into the male screw 50 g of the cylindrical portion 50f.

A set screw hole 70h is formed in the cover peripheral wall 70b. The set screw hole 70h extends in a direction orthogonal to the axial direction of the cover peripheral wall 70b. One end of the set screw hole 70h is open to the outer peripheral surface of the cover peripheral wall 70b. The other end of the set screw hole 70h communicates with a portion of the inner peripheral surface of the cover peripheral wall 70b closer to the cover bottom wall 70a than the female screw 70g. A set screw 71 is screwed into the set screw hole 70h. Then, the set screw 71 comes into contact with the outer peripheral surface of the cylindrical portion 50f, so that the cover member 70 is restricted from moving in the axial direction with respect to the cylindrical portion 50f.

In a state where the cover member 70 is attached to the cylindrical portion 50f, the wiring 68 passes through the wiring insertion hole 70c and protrudes from the cover bottom wall 70a of the cover member 70. The jig groove 69a faces the outside of the cover member 70 via the wiring insertion hole 70c. The outer peripheral portion of the end surface 69e of the terminal block 69 is in contact with the periphery of the wiring insertion hole 70c on the inner surface of the cover bottom wall 70a. As a result, the cover member 70 restricts the movement of the urging spring 66 in the casing 62 by the urging force.

Next, the operation of this embodiment will be described.
As shown in FIG. 4, the plurality of piezo elements 61 are energized via the wiring 68 from the power supply unit, the plurality of piezo elements 61 are elongated, and the expansion of the plurality of piezo elements 61 is followed. When the expansion / contraction portion 62c expands, the casing 62 presses the first valve rod 44 against the urging force of the valve spring 46. Then, when the first valve rod 44 presses the second valve rod 45, the first valve body 40 and the second valve body 42 move integrally. As a result, the first valve body 40 is separated from the first valve seat 38, and the second valve body 42 is separated from the second valve seat 39. Therefore, the first valve body 40 and the second valve body 42 are configured to be integrally movable in the body 11 in the axial direction of the body 11. Then, the first valve body 40 and the second valve body 42 are simultaneously separated from the first valve seat 38 and the second valve seat 39 by the casing 62 extending against the urging force of the valve spring 46.

The first valve body 40 and the second valve body 42 move integrally with respect to the first valve seat 38 and the second valve seat 39 in the directions away from each other, so that the first valve body 40 and the first valve seat 42 are separated from each other. A fluid flow between the second valve body 42 and the second valve seat 39 is allowed as well as a fluid flow between the second valve body 42 and the second valve seat 39. Then, the fluid from the fluid supply source is the first port 16, the first connection passage 17, the second connection passage 18, the communication hole 37, the plug medium diameter hole 34, the first valve chamber 41, the small diameter hole 15a, and the second. It passes through the port 19 and is supplied to the fluid pressure device. Further, the fluid from the fluid supply source passes through the first port 16, the first connection passage 17, the third connection passage 23, the fourth connection passage 24, the second valve chamber 43, the small diameter hole 15a, and the second port 19. And is supplied to the fluid pressure equipment.

As shown in FIG. 1, the energization of the plurality of piezo elements 61 from the power supply unit via the wiring 68 is stopped, the plurality of piezo elements 61 are reduced, and the reduction of the plurality of piezo elements 61 is followed. When the expansion / contraction portion 62c is reduced, the second valve rod 45 moves toward the first valve rod 44 due to the urging force of the valve spring 46. Then, when the second valve rod 45 presses the first valve rod 44, the first valve body 40 and the second valve body 42 move integrally. As a result, the first valve body 40 approaches the first valve seat 38 and sits on the first valve seat 38, and the second valve body 42 approaches the second valve seat 39 and sits on the second valve seat 39. do. Therefore, the first valve body 40 and the second valve body 42 are urged by the valve spring 46 in a direction approaching each of the first valve seat 38 and the second valve seat 39. The first valve body 40 and the second valve body 42 are simultaneously seated on the first valve seat 38 and the second valve seat 39, respectively.

In this way, the casing 62 can be expanded and contracted following the expansion and contraction of the piezo element 61. Then, the piezo actuator 60 integrally moves the first valve body 40 and the second valve body 42 as the piezo element 61 expands and contracts in the axial direction of the body 11.

When the first valve body 40 and the second valve body 42 are seated on the first valve seat 38 and the second valve seat 39, respectively, the fluid flow between the first valve body 40 and the first valve seat 38 is increased. Along with being regulated, the flow of fluid between the second valve body 42 and the second valve seat 39 is regulated. As a result, the first port 16, the first connection passage 17, the second connection passage 18, the communication hole 37, the plug medium diameter hole 34, the first valve chamber 41, the small diameter hole 15a, and the second in the fluid from the fluid supply source. The supply to the fluid pressure device via the port 19 is cut off. Further, the fluid from the fluid supply source is passed through the first port 16, the first connection passage 17, the third connection passage 23, the fourth connection passage 24, the second valve chamber 43, the small diameter hole 15a, and the second port 19. The supply to the fluid pressure equipment is cut off.

At this time, the inner diameter of the first valve seat 38 and the inner diameter of the second valve seat 39 are the same. That is, since the flow path cross-sectional area of the first valve seat 38 and the flow path cross-sectional area of the second valve seat 39 are the same, the pressures of the fluids acting on the first valve body 40 and the second valve body 42 cancel each other out. Will be done. As a result, only the urging force of the valve spring 46 acts on the first valve body 40 and the second valve body 42, so that the seal on the first valve seat 38 in the first valve body 40 and the second valve body 42. The seal to the second valve seat 39 is stable.

As shown in FIG. 5, when positioning the valve seat plug 30, first, in a state where the first valve body 40 and the second valve body 42 are seated on the first valve seat 38 and the second valve seat 39. The jig 72 is fitted into the jig groove 69a, and the jig 72 is used to rotate the casing 62 in the direction in which the plug screw portion 36 is screwed with respect to the female screw hole 15c. At this time, the pair of actuator planes 64 abut against the pair of plug planes 33a, thereby restricting the rotation of the casing 62 with respect to the valve seat plug 30. As a result, in the valve seat plug 30, the plug screw portion 36 is screwed with respect to the female screw hole 15c as the casing 62 rotates, so that the valve seat plug 30 resists the urging force of the valve spring 46 with respect to the casing 62. It moves in the axial direction of the body 11 in the direction of separation. Therefore, as the casing 62 rotates, the valve seat plug 30 is screwed into the inner peripheral surface of the body 11 of the plug threaded portion 36 via the detent portion 65 to resist the urging force of the valve spring 46. The body 11 can be moved in the axial direction.

Then, while the state in which the first valve body 40 is seated on the first valve seat 38 is maintained, the valve seat plug 30 presses the first valve rod 44, and the end surface of the first shaft portion 44a on the first flange portion 44b side. The first valve rod 44 presses the second valve rod 45 in a state where the first valve rod 44 is in surface contact with the end surface of the second shaft portion 45a on the side opposite to the second flange portion 45b. As a result, the second valve body 42 is separated from the second valve seat 39 against the urging force of the valve spring 46, and the fluid flow between the first valve body 40 and the first valve seat 38 is regulated. In this state, fluid flow between the second valve body 42 and the second valve seat 39 is allowed.

The fluid from the fluid source flows through the first port 16, the first connecting passage 17, the third connecting passage 23, the fourth connecting passage 24, the second valve chamber 43, the small diameter hole 15a, and the second port 19. Then, for example, the flow rate of the fluid flowing through the second port 19 is detected by using a flow rate sensor (not shown) that detects the flow rate of the fluid flowing through the second port 19.

When the flow rate sensor detects the flow rate of the fluid flowing through the second port 19, the jig 72 is used to rotate the casing 62 in the direction in which the plug screw portion 36 is screwed back with respect to the female screw hole 15c. As a result, the valve seat plug 30 moves in the axial direction of the body 11 in the direction approaching the casing 62. At this time, since the urging force of the valve spring 46 is transmitted to the first valve rod 44 via the second valve rod 45, the first valve body 40 is first in the direction of approaching the first valve seat 38. The valve rod 44 is urged, and the state in which the first valve body 40 is seated on the first valve seat 38 is maintained. Then, the second valve rod 45 is urged in the direction in which the second valve body 42 approaches the second valve seat 39 by the urging force of the valve spring 46, and the second valve body 42 is seated on the second valve seat 39. ..

As a result, the flow of fluid between the second valve body 42 and the second valve seat 39 is restricted, and the flow rate of the fluid flowing through the second port 19 is not detected by the flow rate sensor. Then, at the timing when the flow rate of the fluid is no longer detected by the flow rate sensor, the rotation of the casing 62 in the direction in which the plug screw portion 36 by the jig 72 is screwed back with respect to the female screw hole 15c is stopped. Further, the set screw 52 is screwed into the set screw hole 50h, and the set screw 52 restricts the axial movement of the body 11 in the valve seat plug 30. As a result, the first valve body 40 and the first valve body 40 and the first valve body 40 and the first valve body 40 and the second The valve seat plug 30 is positioned so that the two valve bodies 42 are simultaneously seated on the first valve seat 38 and the second valve seat 39, respectively. That is, with the first valve body 40 and the second valve body 42 movable integrally, the first valve body 40 and the second valve body 42 simultaneously move to the first valve seat 38 and the second valve seat 39, respectively. The valve seat plug 30 is positioned at the seating position.

As shown in FIG. 6, when positioning the casing 62, first, the cover member 70 is screwed with respect to the male screw 50 g. At this time, the periphery of the wiring insertion hole 70c on the inner surface of the cover bottom wall 70a is in contact with the outer peripheral portion of the end surface 69e of the terminal block 69. As a result, the casing 62 moves toward the valve seat plug 30 against the urging force of the urging spring 66, and the outer surface of the bottom wall 62a of the casing 62 is the first flange portion 44b of the first shaft portion 44a. It contacts the end face on the opposite side in a state of surface contact.

Then, by further screwing the cover member 70 with respect to the male screw 50 g, the first valve rod 44 is pressed against the casing 62, and the first valve rod 44 and the second valve are opposed to the urging force of the valve spring 46. The rod 45 integrally moves in the axial direction of the body 11. As a result, the first valve body 40 and the second valve body 42 move integrally in the directions away from each of the first valve seat 38 and the second valve seat 39, and the first valve body 40 and the first valve A fluid flow between the seat 38 is allowed and a fluid flow between the second valve body 42 and the second valve seat 39 is allowed. Therefore, the casing 62 is screwed into the body 11 of the cover member 70, and the casing 62 resists the urging force of the urging spring 66 and the urging force of the valve spring 46 to resist the urging force of the first valve body 40 and the second valve body. It is integrally movable with the body 11 in the axial direction.

Then, the fluid from the fluid supply source is the first port 16, the first connection passage 17, the second connection passage 18, the communication hole 37, the plug medium diameter hole 34, the first valve chamber 41, the small diameter hole 15a, and the second. It flows through port 19. Further, the fluid from the fluid supply source flows through the first port 16, the first connection passage 17, the third connection passage 23, the fourth connection passage 24, the second valve chamber 43, the small diameter hole 15a, and the second port 19. .. Then, the flow rate of the fluid flowing through the second port 19 is detected by the flow rate sensor.

When the flow rate sensor detects the flow rate of the fluid flowing through the second port 19, the cover member 70 is screwed back with respect to the male screw 50 g. As a result, the casing 62 is brought into contact with the valve seat plug 30 while the periphery of the wiring insertion hole 70c on the inner surface of the cover bottom wall 70a and the outer peripheral portion of the end surface 69e of the terminal block 69 are in contact with each other due to the urging force of the urging spring 66. On the other hand, it moves in the direction of separation. Further, the first valve body 40 and the first valve body 40 and the end surface of the first shaft portion 44a on the opposite side of the first flange portion 44b are in surface contact with each other due to the urging force of the valve spring 46. The first valve rod 44 and the second valve rod 45 move integrally in the direction in which the second valve body 42 approaches the first valve seat 38 and the second valve seat 39, respectively. Therefore, the casing 62 is urged by the urging spring 66 in the direction in which the first valve body 40 and the second valve body 42 approach the first valve seat 38 and the second valve seat 39, respectively. Then, the first valve body 40 and the second valve body 42 are simultaneously seated on the first valve seat 38 and the second valve seat 39, respectively.

As a result, the flow of fluid between the first valve body 40 and the first valve seat 38 is regulated, and the flow of fluid between the second valve body 42 and the second valve seat 39 is regulated. The flow rate of the fluid flowing through the 2 port 19 is not detected by the flow rate sensor. Then, at the timing when the flow rate of the fluid is no longer detected by the flow rate sensor, the threading of the cover member 70 with respect to the male screw 50 g is stopped. Then, the set screw 71 is screwed into the set screw hole 70h, and the set screw 71 regulates the axial movement of the cover member 70 with respect to the cylindrical portion 50f. As a result, the first valve body 40 and the second valve body 42 are in a state where the outer surface of the bottom wall 62a of the casing 62 and the end surface of the first shaft portion 44a on the side opposite to the first flange portion 44b are in surface contact with each other. The casing 62 is positioned at a position where it is simultaneously seated on each of the first valve seat 38 and the second valve seat 39. That is, with the casing 62, the first valve body 40, and the second valve body 42 being integrally movable, the first valve body 40 and the second valve body 42 are the first valve seat 38 and the second valve seat. The casing 62 is positioned at a position where it is seated at the same time on each of the 39s.

In this way, the casing is formed by positioning the valve seat plug 30 and the casing 62 at positions where the first valve body 40 and the second valve body 42 are simultaneously seated on the first valve seat 38 and the second valve seat 39, respectively. When 62 extends against the urging force of the valve spring 46, the first valve body 40 and the second valve body 42 are simultaneously separated from the first valve seat 38 and the second valve seat 39, respectively.

In the above embodiment, the following effects can be obtained.
(1) The valve seat plug 30 having the first valve seat 38 has a plug screw portion 36 screwed into the inner peripheral surface of the body 11. The second valve seat 39 is formed on the body 11. Between the casing 62 and the valve seat plug 30, a detent portion 65 that regulates the rotation of the casing 62 with respect to the valve seat plug 30 is provided. Then, as the casing 62 rotates, the plug screw portion 36 is screwed into the inner peripheral surface of the body 11 via the detent portion 65, and the valve seat plug 30 resists the urging force of the valve spring 46. It is movable in the axial direction of the body 11.

According to this, when the plug screw portion 36 is screwed with respect to the inner peripheral surface of the body 11 with the rotation of the casing 62, the valve seat plug 30 resists the urging force of the valve spring 46 of the body 11. While moving in the axial direction and maintaining the state in which the first valve body 40 is seated on the first valve seat 38, the first valve body 40 and the second valve body 42 move integrally, and the second valve body 42 Is separated from the second valve seat 39. Then, when the plug screw portion 36 was screwed back with respect to the inner peripheral surface of the body 11 with the rotation of the casing 62, the first valve body 40 was seated on the first valve seat 38 by the urging force of the valve spring 46. The second valve body 42 is seated on the second valve seat 39 while the state is maintained. As a result, the first valve body 40 and the second valve body 42 are attached to the first valve seat 38 and the second valve seat 39, respectively, in a state where the first valve body 40 and the second valve body 42 can be integrally moved. The valve seat plug 30 can be positioned at the position where it is seated at the same time.

Further, the cover member 70 is screwed into the body 11, and the casing 62 is integrated with the first valve body 40 and the second valve body 42 against the urging force of the urging spring 66 and the urging force of the valve spring 46. It is movable in the axial direction of the body 11. According to this, when the cover member 70 is screwed with respect to the body 11, the casing 62 moves toward the valve seat plug 30 against the urging force of the urging spring 66, and at the same time, it becomes the urging force of the valve spring 46. Against this, the first valve body 40 and the second valve body 42 are separated from each other with respect to the first valve seat 38 and the second valve seat 39. Then, when the cover member 70 is screwed back to the body 11, the casing 62 has the first valve body 40 and the second valve body 42 has the first valve seat 38 and the second valve seat due to the urging force of the urging spring 66. The first valve body 40 and the second valve body 42 are simultaneously seated on the first valve seat 38 and the second valve seat 39, respectively, by the urging force of the valve spring 46, which is urged in a direction approaching each of the 39. As a result, the casing 62, the first valve body 40, and the second valve body 42 can be integrally moved, and the first valve body 40 and the second valve body 42 become the first valve seat 38 and the second valve. The casing 62 can be positioned at a position where it can be seated on each of the seats 39 at the same time.

In this way, the casing is formed by positioning the valve seat plug 30 and the casing 62 at positions where the first valve body 40 and the second valve body 42 are simultaneously seated on the first valve seat 38 and the second valve seat 39, respectively. When 62 extends against the urging force of the valve spring 46, the first valve body 40 and the second valve body 42 can be simultaneously separated from the first valve seat 38 and the second valve seat 39, respectively. As a result, it is possible to secure a large flow rate in the switching valve 10 while maintaining high responsiveness.

(2) The detent portion 65 that regulates the rotation of the casing 62 with respect to the valve seat plug 30 is formed on the pair of plug planes 33a formed on a part of the inner peripheral surface of the valve seat plug 30 and the actuator insertion portion 63. It is composed of a pair of actuator planes 64. In this way, by forming a pair of plug planes 33a on a part of the inner peripheral surface of the valve seat plug 30 and forming a pair of actuator planes 64 on the actuator insertion portion 63, rotation of the casing 62 with respect to the valve seat plug 30 is performed. The detent portion 65 to be regulated can be easily configured.

(3) The flow path cross-sectional area of the first valve seat 38 and the flow path cross-sectional area of the second valve seat 39 are the same. Therefore, the fluid acting on the first valve body 40 and the second valve body 42 in a state where the first valve body 40 and the second valve body 42 are seated on the first valve seat 38 and the second valve seat 39, respectively. Pressures cancel each other out. As a result, only the urging force of the valve spring 46 acts on the first valve body 40 and the second valve body 42, so that the seal on the first valve seat 38 in the first valve body 40 and the second valve body 42. The seal to the second valve seat 39 is stable.

(4) The screwing direction of the plug screw portion 36 with respect to the inner peripheral surface of the body 11 and the screwing direction of the cover member 70 with respect to the body 11 are the same directions. Therefore, since the valve seat plug 30 and the casing 62 can be positioned in one direction, the assembly work of the switching valve 10 can be facilitated.

(5) Since the casing 62 of the piezo actuator 60 having the existing configuration functions as a jig used for positioning the valve seat plug 30, a jig used for positioning the valve seat plug 30 is separately used. There is no need to prepare it, and the assembly work of the switching valve 10 can be facilitated.

The above embodiment can be modified and implemented as follows. The above embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.

In the embodiment, the detent portion 65 that regulates the rotation of the casing 62 with respect to the valve seat plug 30 is formed on the pair of plug planes 33a formed on a part of the inner peripheral surface of the valve seat plug 30 and the actuator insertion portion 63. It is not limited to the one composed of the pair of actuator planes 64 to be formed. For example, a detent portion is configured from a pair of protrusions protruding from the actuator insertion portion 63 toward the valve seat plug 30, a pair of recesses formed in the valve seat plug 30 and into which the pair of protrusions are fitted, and a detent portion. May be good.

-In the embodiment, the first valve seat 38 is not limited to an annular shape, and may be, for example, a square annular shape. Further, the second valve seat 39 is not limited to an annular shape, and may be, for example, a square annular shape. When the first valve seat 38 has a square annular shape and the second valve seat 39 has a square annular shape, the flow path cross-sectional area of the first valve seat 38 and the flow path cross-sectional area of the second valve seat 39 are different. It may be the same.

-In the embodiment, the flow path cross-sectional area of the first valve seat 38 may be different from the flow path cross-sectional area of the second valve seat 39.
-In the embodiment, a fluid pressure device may be connected to one end of the first port 16 via a pipe or the like, and a fluid supply source may be connected to one end of the second port 19 via a pipe or the like. ..

-In the embodiment, the switching valve 10 may be, for example, a 3-port valve having a supply port, an output port, and a discharge port instead of the 2-port valve.

10 ... switching valve, 11 ... body, 30 ... valve seat plug, 33a ... plug flat surface, 36 ... plug threaded portion, 38 ... first valve seat, 39 ... second valve seat, 40 ... first valve body, 42 ... second 2 valve body, 46 ... valve spring, 60 ... piezo actuator, 61 ... piezo element, 62 ... casing, 63 ... actuator insertion part, 64 ... actuator plane, 65 ... detent part, 66 ... urging spring, 70 ... cover member ..

Claims (3)

With a cylindrical body,
A first valve body and a second valve body configured to be integrally movable in the body in the axial direction of the body,
An annular first valve seat provided in the body and to which the first valve body is brought into contact with and separated from each other.
An annular second valve seat provided in the body and with which the second valve body is brought into contact with and separated from each other.
A piezo actuator that integrally moves the first valve body and the second valve body as the piezo element expands and contracts in the axial direction of the body is provided.
The first valve seat and the second valve seat are oriented in the same direction in the axial direction of the body.
The first valve body and the second valve body are urged by a valve spring in a direction approaching each of the first valve seat and the second valve seat.
The piezo actuator has a casing that accommodates the piezo element and can expand and contract in accordance with the expansion and contraction of the piezo element, and the casing expands against the urging force of the valve spring to cause the first. A switching valve in which the valve body and the second valve body are separated from the first valve seat and the second valve seat, respectively.
The casing is cylindrical and has a cylindrical shape.
A cylindrical valve seat plug having the first valve seat is arranged between the piezo actuator and the first valve body in the body.
The second valve seat is formed on the body and is formed on the body.
The valve seat plug has a plug screw portion screwed into the inner peripheral surface of the body.
A detent portion is provided between the casing and the valve seat plug to regulate the rotation of the casing with respect to the valve seat plug.
As the casing rotates, the plug screw portion is screwed into the inner peripheral surface of the body via the detent portion, and the valve seat plug resists the urging force of the valve spring to counter the shaft. It is possible to move in the direction,
The casing is urged by an urging spring in a direction in which the first valve body and the second valve body approach each of the first valve seat and the second valve seat.
A cylindrical cover member that regulates the movement of the urging spring in the casing due to the urging force is screwed into the body.
The cover member is screwed into the body so that the casing is integrated with the first valve body and the second valve body against the urging force of the urging spring and the urging force of the valve spring. A switching valve characterized by being movable in the axial direction of the body. The casing has an actuator insertion portion that is inserted into the valve seat plug.
The detent portion is
A pair of plug planes formed on a part of the inner peripheral surface of the valve seat plug,
The switching valve according to claim 1, further comprising a pair of actuator planes formed in the actuator insertion portion and capable of contacting the pair of plug planes, respectively. The switching valve according to claim 1 or 2, wherein the flow path cross-sectional area of the first valve seat and the flow path cross-sectional area of the second valve seat are the same.

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