JP2013221543A - Check valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stable valve open state without causing a hunting phenomenon in a check valve.SOLUTION: A check valve includes, in a valve housing 10, an abutting seat part 38 separated from a diaphragm 26 in a state where a valve element 32 is located in a valve closing position while abutting on a diaphragm surface on the secondary chamber 30 side of the diaphragm 26 due to the displacement of the diaphragm 26 in a state where the valve element 32 is located in a valve opening position, to reduce a pressure receiving area on the secondary chamber 30 side of the diaphragm 26.

Description

  The present invention relates to a check valve, and more particularly to a diaphragm check valve.

  As a check valve, a valve housing having an inlet port and an outlet port which define a valve chamber and open to the valve chamber, a valve seat portion defined around an opening end of the inlet port with respect to the valve chamber, and an outer peripheral portion A diaphragm fixed to a valve housing and dividing the valve chamber into a primary chamber including the inlet port and a secondary chamber including the outlet port, and a communication path communicating the primary chamber and the secondary chamber A valve closing position that is supported by the diaphragm and that is seated on the valve seat portion under the displacement of the diaphragm to close the inlet port, and a valve opening position that is spaced apart from the valve seat portion and opens the inlet port. There is known a diaphragm type check valve having a valve body movable between the valve body and a valve closing spring that biases the valve body in a valve closing direction (for example, Patent Document 1).

  In this check valve, when the pressure of the inlet port becomes higher than the pressure of the outlet port by a predetermined value or more, the valve body is separated from the valve seat against the spring force of the valve closing spring, the inlet port is opened, and the inlet port is opened. The fluid flows to the outlet port through the primary chamber, the communication path, and the secondary chamber. In this state, the pressures in the primary chamber and the secondary chamber are substantially equal.

JP 2001-41333 A

  In the check valve as described above, when the area exposed to the primary chamber and the area exposed to the secondary chamber are substantially equal to each other, the pressure in the primary chamber and the secondary chamber is substantially reduced by opening the valve. When equal, almost the same load is applied to both the diaphragm and the valve body. For this reason, the valve element is closed or close to the closed state by the spring force of the valve closing spring. Thereafter, a hunting phenomenon that repeats this state and the valve opening occurs, and a stable valve opening state cannot be obtained. is there.

  The problem to be solved by the present invention is to enable a check valve to obtain a stable valve opening state without causing a hunting phenomenon.

  The check valve according to the present invention comprises a valve housing (10) that defines a valve chamber (16) and has an inlet port (20) and an outlet port (22) open to the valve chamber (16), and the inlet port ( 20) and a valve seat (24) defined around an opening end of the valve chamber (16) with respect to the valve chamber (16), and an outer peripheral portion is fixed to the valve housing (10), and the valve chamber (16) is connected to the inlet port (20). ) Including a primary chamber (28) and a secondary chamber (30) including the outlet port (22), the primary chamber (28), and the secondary chamber (30). The communication passage (36) communicating with the diaphragm (26) and the diaphragm (26) are supported, and the valve seat (24) is seated under the displacement of the diaphragm (26) to close the inlet port (20). The valve position and the inlet spaced apart from the valve seat (24) A valve body (32) movable between a valve opening position for opening the valve (20) and a valve closing spring (34) for urging the valve body (32) in the valve closing direction, When the valve element (32) is located at the valve closing position, the valve element (32) is separated from the diaphragm (26). When the valve element (32) is located at the valve opening position, the diaphragm (26) The valve housing (10) has a contact seat (38) that abuts against the diaphragm surface on the secondary chamber (30) side and reduces the pressure receiving area on the secondary chamber (30) side of the diaphragm (26). Is provided.

  According to this configuration, when the valve body (32) is positioned at the valve opening position, the diaphragm surface on the secondary chamber (30) side of the diaphragm (26) is seated on the contact seat (38), so that the diaphragm ( 26) and the pressure receiving area on the secondary chamber (30) side of the valve body (32) is smaller than the pressure receiving area on the primary chamber (28) side of the diaphragm (26) and valve body (32), A valve opening direction load acting on the secondary chamber (30) side of the diaphragm (26) and the valve body (32) acts on the primary chamber (28) side of the diaphragm (26) and the valve body (32). It will be smaller than the load in the direction. Thereby, the hunting phenomenon which repeats valve opening and valve closing does not occur, and a stable valve opening state is obtained.

  In the check valve according to the present invention, preferably, the valve element (32) is provided at a center position of the diaphragm (26), and the contact seat (38) is provided in an annular shape concentric with the diaphragm (26). Yes.

  According to this configuration, the diaphragm (26) is not twisted and deformed when the diaphragm (26) is seated on the contact seat (38).

  In the check valve according to the present invention, preferably, the communication path is constituted by a through opening (36) provided in the diaphragm (26).

  According to this structure, the communication path which connects the primary chamber (28) and the secondary chamber (30) can be a simple one having only the opening (36) provided in the diaphragm (26).

  According to the check valve of the present invention, when the valve body is located at the valve open position, the diaphragm surface on the side of the secondary chamber of the diaphragm is seated on the abutting seat, so that the pressure received on the side of the secondary chamber of the diaphragm and valve body The area becomes smaller than the pressure receiving area on the primary chamber side of the diaphragm and valve body, and the load in the valve closing direction acting on the secondary chamber side of the diaphragm and valve body is applied to the primary chamber side of the diaphragm and valve body. It becomes smaller than the load in the valve opening direction that acts. Thereby, the hunting phenomenon which repeats valve opening and valve closing does not occur, and a stable valve opening state is obtained.

Sectional drawing which shows the valve closing state of one Embodiment of the check valve by this invention. Sectional drawing which shows the valve opening state of the check valve of the embodiment. The half cross-sectional perspective view which shows the valve closing state of the check valve of the embodiment. The half cross-sectional perspective view which shows the valve opening state of the check valve of the embodiment. The disassembled perspective view of the check valve of the embodiment.

  Hereinafter, one embodiment of a check valve according to the present invention will be described with reference to FIGS.

  The check valve of this embodiment has a valve housing 10 that is a combination of an inlet side housing 12 and an outlet side housing 14. The valve housing 10 defines an airtight cylindrical valve chamber 16. The inlet side housing 12 is formed with an inlet port 20 opened to the valve chamber 16 by a cylindrical body 18 protruding into the valve chamber 16 from the inlet side housing 12. An outlet port 22 that opens to the valve chamber 16 is formed in the outlet side housing 14. An annular valve seat 24 located in the center of the valve chamber 16 is defined around the opening end of the inlet port 20 with respect to the valve chamber 16, that is, at the tip of the cylindrical body 18.

  A diaphragm 26 is attached to the valve housing 10 so that the inlet-side housing 12 and the outlet-side housing 14 sandwich a thick annular mounting outer edge portion 26A from both sides. The diaphragm 26 is entirely made of a rubber-like elastic material, and has a mounting outer edge portion 26A that is a fixed portion to the valve housing 10 and a flexibility that is inside the mounting outer edge portion 26A and is sufficiently thinner than the mounting outer edge portion 26A. The valve chamber 16 is divided into a primary chamber 28 including the inlet port 20 and a secondary chamber 30 including the outlet port 22.

  A valve body 32 is provided at the center of the diaphragm 26. The valve body 32 has a flat plate shape and is integrally formed with the diaphragm 26 in a form in which a required combined rigidity is ensured by thickening the central portion of the diaphragm surface portion 26B of the diaphragm 26 into a disk shape. The valve body 32 is directly opposed to the valve seat portion 24, and is moved to the valve seat portion 24 as shown in FIGS. 1 and 3 under the displacement of the diaphragm 26, that is, with elastic deformation of the diaphragm 26. The valve can be moved between a valve closing position in which it sits and closes the inlet port 20 and a valve opening position in which the inlet port 20 is opened apart from the valve seat portion 24 as shown in FIGS.

  The outlet side housing 14 is formed with a spring seating step 14A. A valve closing spring 34 is attached between the spring seating step 14A and the valve body 32 by a compression coil spring. The valve closing spring 34 acts between the outlet side housing 14 and the valve body 32 and urges the valve body 32 in the valve closing direction, that is, the direction in which the valve seat portion 24 is seated. A plurality of spring retainer pieces 40 protrude from the outlet housing 14 at a portion surrounding the valve closing spring 34.

  A plurality of spring retainer pieces 40 are provided at equal intervals around the valve closing spring 34 to prevent the valve closing spring 34 from being obliquely displaced and deformed. The tip of the spring retainer piece 40 is a valve-opening seating portion 40A on which the valve body 32 in the valve-opening position is seated. Thereby, the valve opening position of the valve body 32 is uniquely determined by the position where the valve body 32 is seated on the valve opening seat portion 40A.

  A plurality of openings 36 are formed through the diaphragm surface portion 26B of the diaphragm 26 at equal intervals around the circumference. The openings 36 form a communication path that allows the primary chamber 28 and the secondary chamber 30 to communicate with each other, and it is preferable that the openings 36 be evenly distributed around the center of the diaphragm 26 in order to avoid torsional deformation of the diaphragm surface portion 26B. .

  The outlet side housing 14 is integrally formed with a contact seat portion 38 that protrudes toward the diaphragm 26 side. The contact seat portion 38 is provided in an annular shape concentric with the diaphragm 26, and when the valve body 32 is located at the valve closing position, as shown in FIGS. 1 and 3, the diaphragm 26. When the diaphragm 26 is displaced further away from the valve opening position, the diaphragm 26 is displaced to contact the surface of the diaphragm surface portion 26B of the diaphragm 26 on the secondary chamber 30 side. In other words, the surface of the diaphragm surface portion 26 </ b> B of the diaphragm 26 on the side of the secondary chamber 30 is seated on the contact seat portion 38 due to the displacement of the diaphragm 26 due to the valve body 32 being positioned at the valve opening position.

  Thereby, when the valve body 32 is in the valve-opening position, compared to when the valve body 32 is in the valve-closed position, the region existing on the outer peripheral side from the annular contact portion with the contact seat portion 38, The pressure receiving area on the secondary chamber 30 side of the diaphragm 26 decreases. In other words, the contact seat portion 38 contacts the surface of the diaphragm surface portion 26B on the secondary chamber 30 side, so that there is 2 in the outer peripheral region from the annular contact portion of the diaphragm surface portion 26B and the contact seat portion 38. The pressure in the next chamber 30 does not work effectively.

  When the valve body 32 is in the closed position, the effective pressure receiving surfaces on the primary chamber 28 side and the secondary chamber 30 side of the diaphragm surface portion 26B are the same on both sides with the connecting portion with the mounting outer edge portion 26A as the outer shell. 26, the pressure receiving area on the primary chamber 28 side and the pressure receiving area on the secondary chamber 30 side are the same, but when the valve body 32 is in the closed position, the annular surface of the diaphragm surface portion 26B and the contact seat portion 38 is formed. The effective pressure receiving surface on the secondary chamber 30 side of the diaphragm surface portion 26B is reduced by the area on the outer peripheral side of the contact portion of the diaphragm surface portion 26B. The pressure receiving area on the chamber 30 side is smaller than the pressure receiving area on the primary chamber 28 side.

  According to the above-described configuration, when the pressure at the inlet port 20 becomes higher than the pressure at the outlet port 22 by a predetermined value or more, the valve body resists the spring force of the valve closing spring 34 by the load in the valve opening direction acting on the valve body 32. 32 is displaced with the diaphragm 26 and is separated from the valve seat portion 24. When the valve body 32 is separated from the valve seat portion 24, the pressure of the inlet port 20 also acts on the diaphragm 26, and the valve body 32 is positioned at the valve opening position where the valve body 32 is seated on the valve opening seat portion 40A all at once. Thereby, the inlet port 20 is fully opened, and the fluid flows from the inlet port 20 to the outlet port 22 through the primary chamber 28, the opening 36, and the secondary chamber 30 with low pressure loss.

  In this state, the pressure in the primary chamber 28 and the pressure in the secondary chamber 30 are substantially equal, but due to the displacement of the diaphragm 26 due to the valve body 32 being located at the valve opening position, the secondary of the diaphragm surface portion 26B of the diaphragm 26 is increased. Since the surface on the chamber 30 side is seated on the contact seat 38, the area (pressure receiving area) where the diaphragm 26 and the valve body 32 are exposed to the secondary chamber 30 is the same as that between the diaphragm surface 26B and the contact seat 38. Since the diaphragm 26 and the valve body 32 are smaller than the area exposed to the primary chamber 28 (pressure receiving area) by the region on the outer peripheral side from the annular contact portion, the diaphragm 26 and the valve body 32 are correspondingly reduced. The load in the valve closing direction acting on the secondary chamber 30 side is smaller than the load in the valve opening direction acting on the primary chamber 28 side of the diaphragm 26 and the valve body 32.

  This load difference is the pressure receiving area of the diaphragm 26 on the secondary chamber 30 side by the contact seat 38 so that the spring force of the valve closing spring 34 is larger than the load in the valve closing direction applied to the diaphragm 26 and the valve body 32. It is only necessary to set a decrease amount.

  Thereby, the hunting phenomenon which repeats valve opening and closing does not occur, and a valve opening state with low pressure loss can be stably obtained.

  In the present embodiment, since the valve body 32 is located at the center position of the diaphragm 26 and the contact seat 38 is provided in an annular shape concentric with the diaphragm 26, the support of the diaphragm 26 by the contact seat 38 is around the center. Therefore, the diaphragm 26 is not twisted and deformed when the diaphragm 26 is seated on the contact seat 38. Thereby, the fall of the durability of the diaphragm 26 is avoided. In addition, since the communication path that communicates the primary chamber 28 and the secondary chamber 30 is configured by the opening 36 provided in the diaphragm 26, the configuration of the communication path is simply the opening 36 provided in the diaphragm 26. In addition, the opening 36 can be formed simultaneously with the formation of the diaphragm 26.

  Although the present invention has been described above with reference to preferred embodiments, the present invention is not limited to such embodiments so that those skilled in the art can easily understand, and departs from the spirit of the present invention. It is possible to change appropriately within the range not to be. For example, the contact seat portion 38 is not limited to an annular shape concentric with the diaphragm, and may be a polygonal annular shape or partially provided in an island shape. The communication passage that communicates the primary chamber 28 and the secondary chamber 30 is not limited to the opening 36 formed in the diaphragm 26, but an internal passage formed in the valve housing 10 or an external pipe piped outside the valve housing 10. You may be comprised by piping. In addition, all the components shown in the above embodiment are not necessarily essential, and can be appropriately selected without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 Valve housing 16 Valve chamber 20 Inlet port 22 Outlet port 24 Valve seat part 26 Diaphragm 28 Primary chamber 30 Secondary chamber 32 Valve body 34 Valve closing spring 36 Opening 38 Contacting seat part

Claims (3)

A valve housing defining a valve chamber and having an inlet port and an outlet port open to the valve chamber;
A valve seat defined around an open end of the inlet port relative to the valve chamber;
A diaphragm having an outer peripheral portion fixed to a valve housing, and dividing the valve chamber into a primary chamber including the inlet port and a secondary chamber including the outlet port;
A communication path communicating the primary chamber and the secondary chamber;
Between a valve closing position that is carried by the diaphragm and is seated on the valve seat under the displacement of the diaphragm and closes the inlet port, and a valve opening position that is spaced apart from the valve seat and opens the inlet port A movable valve body,
A valve closing spring for urging the valve body in the valve closing direction;
When the valve body is in the valve closing position, the valve body is separated from the diaphragm, and when the valve body is in the valve opening position, the diaphragm contacts the diaphragm surface of the diaphragm on the secondary chamber side. A check valve in which a contact seat for reducing a pressure receiving area on the secondary chamber side of the diaphragm is provided in the valve housing.   2. The check valve according to claim 1, wherein the valve body is located at a center position of the diaphragm, and the contact seat portion is provided in an annular shape concentric with the diaphragm.   The check valve according to claim 1, wherein the communication path is configured by a through opening provided in the diaphragm.

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