JP2012057678A - Pilot type bidirectional solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pilot type bidirectional solenoid valve capable of making positioning of a plunger and a check valve assembly in a rotation direction to a main valve body unnecessary, hardly generating wear of a constituent member, hardly generating actuation failure, leakage and the like and enhancing durability, reliability and the like.SOLUTION: An upper end opening of a first communication path is provided in a position eccentrically deviated from a center line O of a solenoid valve 10 to an outer circumferential side in a radial direction by a prescribed distance and an upper end opening of a second communication path is provided on the center line O of the solenoid valve, a first check valve body is formed in a short cylindrical shape having an annular seal surface 51c having the center line O of the solenoid valve as a center and a second check valve body having a circular seal surface 52c is disposed at an inner peripheral side center part of the first check valve body, so that the upper end openings of the first and the second communication paths 41 and 42 can be reliably closed by the first and the second check valve bodies 51 and 52 regardless of positions of the plunger 25 and the check valve assembly 50 in a rotational direction to the main valve body 30.

Description

  In the present invention, for example, a fluid (refrigerant) flows in both forward and reverse directions (first flow direction and second flow direction) as in a multi-air conditioner system in which a plurality of small indoor units are installed for one outdoor unit. In particular, the present invention relates to a pilot-type bidirectional solenoid valve capable of reliably opening and closing a flow path with a small driving force regardless of the flow direction.

  This type of pilot-type bidirectional solenoid valve is configured such that, as seen in, for example, Patent Document 1 below, the pilot valve body and the pressure-introducing (equalizing) valve body serve as a single check valve body. Two check valve bodies are provided for the first flow direction and the second flow direction.

  More specifically, the conventional general pilot-type bidirectional solenoid valve generally includes an electromagnetic actuator having a coil, an attractor, a plunger, etc., a check valve assembly provided at a lower portion of the plunger, and a piston type A main valve body, a cylindrical space into which the main valve body is slidably inserted, and a main valve port opened and closed by the main valve body, provided above the main valve body in the cylindrical space A pilot chamber in which the check valve assembly is disposed, and a valve housing in which a main valve chamber is defined below the main valve body. A first inlet / outlet directly connected to the main valve chamber and a second inlet / outlet connected to the main valve chamber via the main valve port are provided, and the main valve chamber and the pilot chamber are provided in the main valve body. A first communication passage for communicating, the second inlet / outlet and the pilot A second communication passage for communicating with the chamber is formed, and the check valve assembly allows inflow from the main valve chamber to the pilot chamber through the first communication passage, but from the pilot chamber. Inflow from the second inlet / outlet to the pilot chamber is allowed through the first check valve body and the second communication passage to prevent outflow to the main valve chamber, but from the pilot chamber to the second A second check valve body that prevents outflow to the inlet / outlet is provided.

JP-A-6-101780

  In the pilot-type bidirectional solenoid valve described in Patent Document 1, the first and second check valve bodies are needle-shaped, and the needle-shaped first and second check valve bodies are used as check valves. Since the first and second communication passages are opened and closed by connecting and disconnecting the upper end openings (valve seat portions) of the first and second communication passages through the guide holes provided in the assembly, the main valve If the position of the plunger (check valve assembly) in the rotational direction is deviated from the body, the first and second communication passages cannot be opened and closed by the first and second check valve bodies. Therefore, in this bidirectional solenoid valve, in addition to the first and second check valve bodies, there are two on the bottom surface of the check valve assembly so that the plunger does not shift in the rotation direction with respect to the main valve body. And a guide hole into which the guide rod is inserted is provided in the main valve body to position the plunger (check valve assembly) in the rotational direction with respect to the main valve body.

  However, in the above bidirectional solenoid valve, during the valve opening / closing operation, the first and second check valve bodies and the two guide rods are moved in the axial direction in a state of being inserted into the guide holes, respectively. These wears easily, and the durability decreases due to the wear, and the sliding surface gap (clearance) formed between the members widens, so that the refrigerant easily leaks. Foreign matter (cutting scraps, abrasives, wear due to sliding friction, dust from the outside, etc.) remaining at the time of processing and assembly are easily caught, and malfunctions such as locks are likely to occur.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to eliminate positioning of the plunger and the check valve assembly in the rotational direction with respect to the main valve body, and to wear components. It is an object of the present invention to provide a pilot-type bidirectional solenoid valve that can prevent the occurrence of malfunction, leakage, and the like, and can improve durability, reliability, and the like.

  In order to achieve the above object, a pilot-type bidirectional solenoid valve according to the present invention basically includes an electromagnetic actuator having a coil, an attractor, a plunger, and the like, and a check valve provided at the lower portion of the plunger. An assembly, a piston-type main valve body, a cylindrical space into which the main valve body is slidably inserted, and a main valve port opened and closed by the main valve body are provided. A pilot chamber in which the check valve assembly is disposed above the main valve body and a valve housing in which a main valve chamber is defined below the main valve body; The valve housing is provided with a first inlet / outlet directly connected to the main valve chamber and a second inlet / outlet connected to the main valve chamber via the main valve port, and the main valve chamber includes the main valve chamber. And the second entrance / exit for communicating with the pilot chamber A second communication passage for communicating with the pilot chamber is formed, and the check valve assembly allows inflow from the main valve chamber to the pilot chamber through the first communication passage, but the pilot valve A first check valve body that prevents outflow from the chamber to the main valve chamber, and an inflow from the second inlet / outlet to the pilot chamber via the second communication passage is allowed, but the pilot chamber A second check valve body for preventing outflow to the second inlet / outlet; the first check valve body and / or the second check valve body in the first communication path and / or the second communication path; It has an annular or circular sealing surface around the center line of the solenoid valve, which can close the opening on the pilot chamber side.

  In a preferred embodiment, the first check valve body or the second check valve body has a short cylindrical shape, and a circle is formed at the inner peripheral side center of the first check valve body or the second check valve body having the short cylindrical shape. A second check valve body or a first check valve body having a plate-like portion is disposed.

  In another preferred aspect, the opening on the pilot chamber side of the first communication passage is provided at a portion eccentric from the center line of the electromagnetic valve by a predetermined distance from the radial outer circumferential side, and the opening of the second communication passage is The opening on the pilot chamber side is provided on the center line of the solenoid valve.

  The check valve assembly preferably includes a support base attached to a lower portion of the plunger, and the support base supports the first check valve body having a short cylindrical shape so as to be movable in the axial direction. A large-diameter cylindrical portion for retaining and locking, and a second check valve body that is disposed in the center on the inner peripheral side of the first check valve body and that has a disk-like portion is movably supported in the axial direction. A small-diameter cylindrical portion for retaining and locking, a compression coil spring that biases the first check valve body downward, and a compression coil spring that biases the second check valve body downward. The

  In another preferred aspect, a throttle valve that restricts a flow rate from the second inlet / outlet to the pilot chamber but does not limit a flow rate from the pilot chamber to the second inlet / outlet is disposed in the second communication path. The

  In the pilot-type bidirectional solenoid valve according to the present invention, for example, the first check valve body has a short cylindrical shape having an annular sealing surface centered on the center line of the solenoid valve, and the short cylindrical first 1 Since the second check valve body having a circular sealing surface is disposed at the center on the inner peripheral side of the check valve body, the position of the plunger and the check valve assembly in the rotational direction is relative to the main valve body. The upper end opening (valve seat portion) of the first communication path and the second communication path can be reliably closed by the first check valve body and the second check valve body.

  Therefore, positioning of the plunger and the check valve assembly in the rotational direction with respect to the main valve body is not necessary, and positioning is performed by inserting two check valve bodies and two guide rods into the guide holes as in the conventional example. As compared with the case of performing the above, it is possible to make it difficult for the component members to be worn, to reduce leakage, and to make it difficult to cause malfunctions such as a lock due to foreign object biting, thereby improving durability and reliability. it can.

The longitudinal cross-sectional view which shows one Example of the pilot type bidirectional | two-way solenoid valve which concerns on this invention. The enlarged view of the principal part of the bidirectional | two-way solenoid valve shown by FIG. The 1st non-return valve body shown by FIG. 1 is shown, (A) is a top view, (B) is BB arrow sectional drawing of (A), (C) is a perspective view. The 2nd non-return valve body shown by FIG. 1 is shown, (A) is a top view, (B) is BB arrow sectional drawing of (A). The throttle valve shown by FIG. 1 is shown, (A) is a top view, (B) is BB arrow sectional drawing of (A), (C) is CC arrow sectional drawing of (B). The figure which is provided to description of the 1st flow direction opening-closing operation | movement <the 1> in the bidirectional | two-way solenoid valve of an Example. The figure which is provided to description of the 1st flow direction opening / closing operation | movement <the 2> in the bidirectional | two-way solenoid valve of an Example. The figure which is provided for description of the 1st flow direction opening / closing operation | movement <the 3> in the bidirectional | two-way solenoid valve of an Example. The figure which is provided to description of the 1st flow direction opening-closing operation | movement <the 4> in the bidirectional | two-way solenoid valve of an Example. The figure which is provided to description of the 2nd flow direction opening-closing operation | movement <the 1> in the bidirectional | two-way solenoid valve of an Example. The figure which is provided for description of the 2nd flow direction opening-and-closing operation | movement <the 2> in the bidirectional | two-way solenoid valve of an Example. The figure which is provided for description of the 2nd flow direction opening / closing operation | movement <the 3> in the bidirectional | two-way solenoid valve of an Example. The figure which is provided for description of the 2nd flow direction opening-closing operation | movement <the 4> in the bidirectional | two-way solenoid valve of an Example.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing an embodiment of a pilot-type bidirectional electromagnetic valve according to the present invention, and FIG. 2 is an enlarged sectional view showing a main part of the bidirectional electromagnetic valve shown in FIG.

  The pilot-type bidirectional solenoid valve 10 of the illustrated embodiment has a plurality of small indoor units installed for one outdoor unit, and the fluid (refrigerant) is in both forward and reverse directions (first flow direction and second flow direction). And includes an electromagnetic actuator 20, a piston-type main valve body 30, and a valve housing 12.

  The electromagnetic actuator 20 is a coil 22 for energizing excitation, a case 21 disposed so as to cover the outer periphery of the coil 22, and an upper inner peripheral side of the coil 22 and fixed to the case 21 by bolts 28. A suction element 24 and a plunger 25 disposed opposite to the suction element 24 are provided. A conical concave portion 24a is formed at the lower portion of the suction element 24, and a convex portion 25a that fits into the concave portion 24a is provided at the upper portion of the plunger 25. The plunger 25 is slidably fitted into a guide pipe 26 having an upper portion disposed between the coil 22 and the attractor 24. The upper end of the guide pipe 26 is brazed and fixed to the outer peripheral step portion of the suction element 24, and the lower portion thereof is inserted into a mounting port 12a provided at the center of the upper surface portion of the valve housing 12 (upper body 12A) and brazed. It is fixed by.

  A check valve assembly 50 (described later in detail) is assembled to the lower portion of the plunger 25 so as to be movable in the axial direction integrally with the plunger 25. Further, a plunger spring (compression coil spring) 27 that biases the plunger 25 downward is provided between the suction element 24 and the plunger 25.

  The valve housing 12 includes a cylindrical upper body 12A with a ceiling portion 12b having an open bottom surface, and a lower body 12B having a convex cross section to which the upper body 12A is screwed, and the piston-type main valve body. A cylindrical space 13 into which a slidable member 30 is slidably inserted and a main valve port (valve seat portion) 14 opened and closed by the main valve body 30 are provided above the main valve body 30 in the cylindrical space 13. A pilot chamber 16 is defined, and a main valve chamber 15 is defined below the main valve body 30.

  The center line O of the bidirectional solenoid valve 10 of the present embodiment is the same as the common center line of the plunger 25, the check valve assembly 50, the valve housing 12 (the cylindrical space 13 thereof), the main valve body 30, and the like. It has become.

  A first inlet / outlet 31 directly connected to the main valve chamber 15 is provided on the lower left side of the valve housing 12, and a first inlet / outlet 31 connected to the main valve chamber 15 via the main valve port 14 is provided on the lower right side of the valve housing 12. Two entry / exit ports 32 are provided. The first inlet / outlet 31 is connected to the outdoor unit via a conduit 61, and the second inlet / outlet 32 is connected to the indoor unit via a conduit 62.

  Here, the flow in which the high-pressure refrigerant is introduced into the first inlet / outlet 31 and the main valve chamber 15 through the conduit 61 is referred to as a first flow (direction), and the high-pressure refrigerant is in the second inlet / outlet through the conduit 62. The flow introduced into 32 is referred to as a second flow (direction).

  The main valve body 30 has a reverse-convex outer shape in cross section, and has a short cylindrical shape made of rubber, Teflon (registered trademark) or the like that opens and closes the main valve port (valve seat portion) 14 at its bottom. A short cylindrical stopper 34 is provided on the outer periphery of the upper surface of the sealing member 33 so as to contact the ceiling 12b of the valve housing 12 and determine the upper movement limit of the main valve body 30. A seal material (piston ring) 39 is attached to the outer peripheral portion near the upper surface.

  Further, the compression coil spring 35 is compressed between the upper step portion of the main valve body 30 and the inner peripheral step portion of the lower body 12B of the valve housing 12 to urge the main valve body 30 upward (in the valve opening direction). It is disguised.

  In the main valve body 30, a first communication passage 41 for communicating the main valve chamber 15 and the pilot chamber 16 and a second communication for communicating the second inlet / outlet 32 and the pilot chamber 16 are provided. A passage 42 is formed.

  The first communication passage 41 has a larger hole diameter than the vertical hole 41a, which is connected to a vertical hole (equal pressure port) 41a having a relatively small hole diameter whose upper end opens in the upper surface portion 30a of the main valve body 30, and a lower end of the vertical hole 41a. The upper end opening (valve seat portion) of the vertical hole 41a is provided at a portion eccentric from the center line O of the electromagnetic valve 10 by a predetermined distance from the radial direction outer peripheral side.

  The second communication passage 42 is open to the upper surface portion 30a of the main valve body 30 and is continuous with the vertical hole (pilot port) 42a having a larger diameter than the vertical hole 41a of the first communication passage 41 and the lower end of the vertical hole 42a. It consists of a loading hole 42b having a diameter larger than that of the vertical hole 42a and into which a throttle valve 45 described later is slidably loaded. Both the vertical hole 42a and the loading hole 42b are provided on the center line O.

  On the other hand, the check valve assembly 50 assembled to the lower portion of the plunger 25 includes a stepped columnar support base 55 having a large diameter portion and a small diameter portion. The support base 55 includes a large-diameter head portion 55a, an intermediate small-diameter portion 55b, a central large-diameter portion 55c, and a lower small-diameter cylindrical portion 55d in order from the top, as can be understood with reference to the enlarged view of FIG. . The large-diameter head portion 55a is slidably inserted into a reverse concave hole 25b provided in the lower portion of the plunger 25, and is prevented from coming off by a ring-shaped locking piece 29 fixed by caulking to the lower end portion of the plunger 25. It is locked.

  The upper part of the large-diameter cylindrical body 56 is caulked and fixed (caulking part 56a) to the outer periphery of the central large-diameter part 55c (annular groove 55f formed therein), and the lower inner peripheral surface of the large-diameter cylindrical body 56 And a first check valve body 51 is slidably inserted in the axial direction between the outer peripheral surface of the lower small-diameter cylindrical portion 55d.

  As shown in FIG. 3, the first check valve body 51 has a stepped short cylindrical shape composed of an upper large-diameter portion 51a and a lower small-diameter portion 51b, and the bottom surface of the first check valve body 51 is the first communication passage 41 (vertical hole). 41a) is an annular sealing surface 51c that can close the upper end opening (valve seat portion) of the solenoid valve 10 with the center line O as the center. The first check valve body 51 is configured such that an upper large diameter portion 51 a is prevented from coming off by a lower end bent portion 56 b of the large diameter cylindrical body 56, and the first check valve body 51 is connected to the first check valve body 51. A compression coil spring 53 that biases the first check valve body 51 downward is interposed between the central large-diameter portion 55 c of the support base 55.

  A second check valve body 52 is fitted on the inner periphery of the lower small diameter cylindrical portion 55d of the support base 55 so as to be slidable in the axial direction. As shown in FIG. 4, the second check valve body 52 has, for example, a spur gear shape composed of a thick disk-like portion 52a and six teeth 52b provided at equiangular intervals on the outer periphery thereof. A circular shape around the center line O of the electromagnetic valve 10, in which the bottom surface (lower surface) of the disc-shaped portion 52 a can close the upper end opening (valve seat portion) of the second communication passage 42 (the vertical hole 42 a thereof). The sealing surface 52c. The second check valve body 52 is configured such that the outer periphery (tooth 52b) of the second check valve body 52 is retained by a C-shaped ring or the like fixed to the lower end portion of the lower small-diameter cylindrical portion 55d. A compression coil spring 54 for biasing the second check valve body 52 downward is interposed between the check valve body 52 and the central large diameter portion 55c of the support base 55. A space between the teeth 52b and the teeth 52b in the second check valve body 52 serves as a refrigerant flow path.

  The plunger 25, the support base 55, the large-diameter cylindrical body 56, and the lower small-diameter cylindrical portion 55d are formed with through holes (equal pressure holes) 67, 68, 58, and 59 that allow the inside and outside to communicate with each other. .

  The throttle valve 45 inserted into the loading hole 42b of the second communication passage 42 restricts the flow rate from the second inlet / outlet 32 to the pilot chamber 16 via the second communication passage 42, but the second flow passage from the pilot chamber 16 to the second one. As shown in FIG. 5, the flow rate toward the inlet / outlet 32 is not limited. The crescent-shaped space S is formed between the inner peripheral surface of the loading hole 42b and the parallel chamfered portion 45c. When the refrigerant does not flow through the second communication passage 42, the throttle valve 45 is seated by its own weight on a nut 48 with a retaining latch that is screwed into the lower portion of the loading hole 42b. .

  A small hole 46 having a smaller diameter than the vertical holes 41a and 42a is formed at the top of the hollow head 45a, and a relatively large diameter through hole 47 is formed in the parallel chamfered portion 45c of the hollow body 45b. In addition to the small hole 46, the crescent-shaped space S and the through hole 47 serve as a refrigerant flow passage.

  When the throttle valve 45 is pushed up, the upper portion of the hollow head 45a is inserted into the lower end portion of the vertical hole 42a and presses against the lower end edge thereof. Therefore, the refrigerant from the second inlet / outlet 32 to the pilot chamber 16 passes only through the small hole 46, and the flow rate is reduced.

  Next, the opening / closing operation of the bidirectional solenoid valve 10 configured as described above is performed in the first flow direction in which high-pressure refrigerant is introduced into the first inlet / outlet 31 and the main valve chamber 15 via the conduit 61 (FIG. 6). 9 to 9) and the case of the second flow direction in which the high-pressure refrigerant is introduced into the second inlet / outlet 32 through the conduit 62 (FIGS. 10 to 13).

  In the case of the first flow direction, when the coil 22 is not energized, the high pressure in the first inlet / outlet 31 and the main valve chamber 15 is caused by the annular sealing surface 51c of the first check valve body 51 through the first communication passage 41. Act on. Therefore, as shown in FIG. 6, the first check valve body 51 is pushed up slightly, and high pressure is introduced into the pilot chamber 16. Thereby, since a high pressure acts on the upper surface of the main valve body 30, the main valve body 30 presses against the main valve port 14 and closes it.

  Next, when the coil 22 is energized, as shown in FIG. 7, the plunger 25 is attracted to the attractor 24, and together with the plunger 25, the check valve assembly 50 (the first check valve body 51 and the first check valve body 51). 2 check valve body 52) is also lifted upward, and first communication path 41 and second communication path 42 (the upper end opening thereof) are opened.

  In this case, since the hole diameter of the second communication path 42 (the vertical hole 42a) is larger than the hole diameter of the first communication path 41 (the vertical hole 41a), as shown in FIG. Is discharged to the second inlet / outlet 32 side through the second communication passage 42 and the throttle valve 45 disposed there, so that the pressure in the pilot chamber 16 becomes smaller than the pressure in the main valve chamber 15. Therefore, the main valve body 30 is pushed up, the main valve port 14 is opened, and the high-pressure refrigerant flows from the first inlet / outlet 31 → the main valve chamber 15 → the main valve port 14 → the second inlet / outlet 32.

  Next, when the energization of the coil 22 is stopped, the suction force by the attractor 24 is lost, and therefore the plunger 25 and the check valve assembly 50 (the first check valve body 51 and the second reverse valve body 50) are urged by the biasing force of the plunger spring 27. As shown in FIG. 9, the first check valve body 51 and the second check valve body 52 cause the first communication passage 41 and the second communication passage 42 (the upper end opening thereof) to be opened. The valve is closed. When the first communication passage 41 and the second communication passage 42 are closed, the pressure in the pilot chamber 16 is not discharged to the low pressure side (second inlet / outlet 32). Therefore, as in the case shown in FIG. 6, the high pressure of the first inlet / outlet 31 and the main valve chamber 15 acts on the first check valve body 51 via the first communication passage 41, and the first check valve body 51 is pushed up slightly, but high pressure is introduced into the pilot chamber 16, so that high pressure acts on the upper surface of the main valve body 30, and the main valve body 30 is pushed down to close the main valve port 14.

  On the other hand, in the second flow direction, when the coil 22 is not energized, the high pressure of the second inlet / outlet 32 acts on the second check valve body 52 via the second communication passage 42. Therefore, as shown in FIG. 10, the second check valve body 52 is pushed up slightly, but high pressure is introduced into the pilot chamber 16. Thereby, since a high pressure acts on the upper surface of the main valve body 30, the main valve body 30 presses against the main valve port 14 and closes it.

  Next, when the coil 22 is energized, as shown in FIG. 11, the plunger 25 is attracted to the attractor 24, and together with the plunger 25, the check valve assembly 50 (the first check valve body 51 and the first check valve body 51). 2 check valve body 52) is also lifted upward, and first communication path 41 and second communication path 42 (the upper end opening thereof) are opened.

  In this case, when the second check valve body 52 is pulled up to open the second communication passage 42 and high pressure passes through the second communication passage 42, the throttle valve 45 is pushed upward as shown in FIG. The upper end portion of the truncated cone-shaped hollow head 45a is inserted into the lower end portion of the vertical hole 42a and press-contacts the lower end edge thereof. Therefore, the refrigerant from the second inlet / outlet 32 to the pilot chamber 16 passes only through the small hole 46, and the flow rate is reduced. Since the hole diameter of the first communication passage 41 (the vertical hole 41a thereof) is larger than the hole diameter of the small hole 46 of the throttle valve 45, the pressure in the pilot chamber 16 is supplied to the first inlet / outlet through the first communication passage 41. The pressure in the pilot chamber 16 becomes smaller than the pressure in the main valve chamber 15. Therefore, the main valve body 30 is pushed up, the main valve port 14 is opened, and the high-pressure refrigerant flows from the second inlet / outlet 32 → the main valve port 14 → the main valve chamber 15 → the first inlet / outlet 31.

  Next, when the energization of the coil 22 is stopped, the suction force by the attractor 24 is lost, and therefore the plunger 25 and the check valve assembly 50 (the first check valve body 51 and the second reverse valve body 50) are urged by the biasing force of the plunger spring 27. As shown in FIG. 13, the first check valve body 51 and the second check valve body 52 cause the first communication path 41 and the second communication path 42 (the upper end opening thereof) to be pushed down. The valve is closed. When the first communication path 41 and the second communication path 42 are closed, the pressure in the pilot chamber 16 is not discharged to the low pressure side (first inlet / outlet 31). Therefore, as in the case shown in FIG. 10, the high pressure of the second inlet / outlet 32 acts on the second check valve body 52 via the second communication passage 42, and the second check valve body 52 is slight. Is pushed up and high pressure is introduced into the pilot chamber 16, so that high pressure acts on the upper surface of the main valve body 30, and the main valve body 30 is pushed down to close the main valve port 14.

  In the pilot-type bidirectional solenoid valve 10 of the present embodiment that operates as described above, the upper end opening (valve seat portion) of the first communication passage 41 is a predetermined distance from the center line O of the solenoid valve 10 toward the outer periphery in the radial direction. The upper end opening (valve seat portion) of the second communication passage 42 is provided on the center line O of the electromagnetic valve 10, and the first check valve body 51 is the center of the electromagnetic valve 10. A short cylindrical shape having an annular sealing surface 51c centered on the line O, and a circular plate shape having a circular sealing surface 52c at the inner peripheral side center of the first cylindrical check valve body 51. Since the second check valve body 52 is disposed, the first check valve body 51 is located at any position in the rotational direction of the plunger 25 and the check valve assembly 50 with respect to the main valve body 30. And the second check valve body 52 by the upper end openings (valve seals) of the first communication passage 41 and the second communication passage 42. Preparative part) can be reliably closed.

  Therefore, positioning of the plunger 25 and the check valve assembly 50 in the rotational direction with respect to the main valve body 30 is not necessary, and two check valve bodies and two guide rods are inserted into the guide holes as in the conventional example. Compared to positioning, it is possible to make the components less likely to wear, to reduce leakage, and to prevent malfunctions such as locking due to foreign object biting, resulting in improved durability and reliability. Can be made.

DESCRIPTION OF SYMBOLS 10 Pilot type bidirectional solenoid valve 12 Valve housing 13 Cylindrical space 14 Main valve port 15 Main valve chamber 16 Pilot chamber 20 Electromagnetic actuator 22 Coil 24 Suction element 25 Plunger 27 Plunger spring 30 Main valve body 31 First inlet / outlet 32 Second inlet / outlet 35 Compression coil spring 41 First communication passage 41a Vertical hole 42 Second communication passage 42a Vertical hole 45 Throttle valve 50 Check valve assembly 51 First check valve body 51c Annular seal surface 52 Second reverse Stop valve body 52c Circular seal surface 53 Compression coil spring 54 Compression coil spring 55 Support base 55d Lower small diameter cylindrical portion
56 Large diameter cylindrical body

Claims (5)

An electromagnetic actuator having a coil, an attractor, a plunger, etc., a check valve assembly provided at the lower part of the plunger, a piston-type main valve body, and a cylinder into which the main valve body is slidably fitted A pilot valve chamber in which the check valve assembly is disposed above the main valve body in the cylindrical space is defined. And a valve housing in which a main valve chamber is defined below the main valve body, the valve housing via a first inlet / outlet directly connected to the main valve chamber and the main valve port A second inlet / outlet that communicates with the main valve chamber, and a first communication passage for communicating the main valve chamber with the pilot chamber, the second inlet / outlet, and the pilot chamber in the main valve body. A second communication passage is formed for communicating the check valve assembly, A first check valve body that allows inflow from the main valve chamber to the pilot chamber through the first communication passage but prevents outflow from the pilot chamber to the main valve chamber; and A pilot-type bidirectional electromagnetic having a second check valve body that allows inflow from the second inlet / outlet to the pilot chamber through a passage but prevents outflow from the pilot chamber to the second inlet / outlet. A valve,
The first check valve body and / or the second check valve body is centered on a center line of the solenoid valve that can close the opening on the pilot chamber side in the first communication path and / or the second communication path. A pilot-type bidirectional solenoid valve having an annular or circular sealing surface.   The first check valve body or the second check valve body has a short cylindrical shape, and a disk-shaped portion is provided at the inner peripheral side center of the first cylindrical check valve body or the second check valve body. The pilot-type bidirectional solenoid valve according to claim 1, wherein the second check valve body or the first check valve body is disposed.   The opening on the pilot chamber side of the first communication path is provided at a portion eccentric from the center line of the solenoid valve by a predetermined distance from the radial outer peripheral side, and the opening on the pilot chamber side of the second communication path is The pilot-type bidirectional solenoid valve according to claim 1, wherein the pilot-type bidirectional solenoid valve is provided on a center line of the solenoid valve.   The check valve assembly includes a support base attached to a lower portion of the plunger, and the support base supports the first check valve body having a short cylindrical shape so as to be movable in the axial direction and is also provided with a stopper. A large-diameter cylindrical portion that stops, and a second check valve body that is disposed in the center on the inner peripheral side of the first check valve body and that has a disk-like portion is movably supported in the axial direction and is also provided with a stopper. A small-diameter cylindrical portion that stops, a compression coil spring that biases the first check valve body downward, and a compression coil spring that biases the second check valve body downward. The pilot-type bidirectional solenoid valve according to any one of claims 1 to 3.   A throttle valve is provided in the second communication path, which restricts a flow rate from the second inlet / outlet to the pilot chamber but does not limit a flow rate from the pilot chamber to the second inlet / outlet. A pilot-type bidirectional solenoid valve according to any one of claims 1 to 4.

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