JP7190732B2 - Pressure reducing valve - Google Patents

Description

The technology disclosed in the present application relates to a pressure reducing valve used in hot water supply equipment and the like, and more particularly to a pressure reducing valve having a mechanism for preventing damage to the valve body due to water hammer or freezing of water pipes upstream of the water heater.

Conventionally, hot water supply equipment is provided with a pressure reducing valve for supplying tap water at an appropriate pressure to a hot water storage tank having a heater. When the pressure reducing valve is closed, if water hammer occurs in the water pipe on the upstream side or the pipe line freezes, the pressure of the water hammer and the pressure due to the freezing expansion of the water will increase the pressure in the inlet chamber of the valve box. Patent Document 1 and the like disclose a pressure reducing valve provided with a mechanism for preventing damage to the interior of the inlet chamber in order to prevent the interior of the inlet chamber from being damaged by the pressure.

In Patent Document 1, a partition located on the opposite side of the water inlet with respect to the main valve (of the pressure reducing valve) in the inlet chamber releases the water pressure that rises when the water inlet side freezes from the water inlet side to the water outlet side. A pressure reducing valve is disclosed in which a valve is provided to prevent cracking or breakage due to increased water pressure in the inlet chamber.

JP 2015-194950 A

The pressure reducing valve disclosed in Patent Document 1 constitutes a relief valve separately from the pressure reducing valve, and when the pressure of water hammer or the pressure due to freezing and expansion of water is applied to the inlet chamber, the relief valve opens to open the water outlet. Since the pressure is released to the side, the structure of the pressure reducing valve itself becomes complicated, and there is a problem that the manufacturing cost increases.

The technology disclosed in the present application has been proposed in view of the above problems, and provides a pressure reducing valve that can prevent the valve body from being destroyed due to the pressure of water hammer or freezing expansion of water by adding a simple configuration. intended to provide

To achieve the above object, a pressure reducing valve according to claim 1 comprises a primary chamber, a secondary chamber communicating with the primary chamber via a valve port, and a valve body movable to change the opening of the valve port. a valve seat on which a valve body formed in the valve port is seated; a first opening provided on the upper end side of the valve body; a diaphragm closing the first opening; , a pressure-receiving chamber communicating with a secondary chamber, and a first biasing member integrally biasing the diaphragm and the valve body in the direction of opening the valve port, wherein the lower end of the valve body A second opening is provided in the upper part, and the second opening fits the lower end of the valve body to form a release chamber consisting of the lower end surface of the valve body and the second opening. A movable top that is movable in the vertical direction, a pressure relief slit that is provided at the upper end of the movable top and communicates with the relief chamber when the movable top moves downward, and a pressure relief slit of the movable top. and a second biasing member that biases the movable piece in the direction of closing.

A pressure reducing valve according to claim 2 is the pressure reducing valve according to claim 1, wherein the valve element is provided with a communication passage for communicating the relief chamber and the secondary chamber.

In the pressure reducing valve according to claim 1, when the pressure in the primary chamber exceeds a predetermined value due to freezing or the like, the pressure in the primary chamber causes the valve body to move against the biasing force of the first biasing member against the valve seat. The valve is seated to close the valve opening, and the movable piece moves downward against the biasing force of the second biasing member to open the pressure relief slit, and the lower end face of the valve body and the movable piece move downward. Since the volume of the escape chamber (that is, the volume of the primary chamber is increased), the pressure in the primary chamber is relieved, and freeze fracture of the primary chamber can be prevented.

In the pressure reducing valve according to claim 2, by providing a communication passage in the valve body that communicates the relief chamber, which is formed by the lower end surface of the valve body and the opening of the movable piece, with the secondary chamber, the volume of the relief chamber can be increased only by increasing the volume of the relief chamber. In the event of an impracticable increase in pressure in the primary chamber, the pressure in the primary chamber can be released to the secondary chamber via the pressure relief slit and passageway.

As described above, by adding a simple structure in which the movable piece is arranged on the lower end side of the valve body of the pressure reducing valve, it is possible to prevent the freeze fracture of the primary chamber, so that the manufacturing cost can be suppressed. Moreover, unlike the pressure reducing valve disclosed in Patent Document 1, there is no need to provide a relief valve at a position separate from the pressure reducing valve, so the size of the pressure reducing valve can be suppressed and the size can be reduced.

1 is a perspective view of a pressure reducing valve that is an embodiment according to the present invention; FIG. (A) A cross-sectional view of the pressure reducing valve in an open state, (B) a cross-sectional view of the pressure reducing valve in a closed state. It is (A) a front view of a valve body, (B) is a side view. They are (A) top perspective view, (B) front perspective view, (C) side perspective view, and (D) bottom perspective view of the movable piece which comprises a pressure relief mechanism. They are (A) top perspective view, (B) front side perspective view, (C) side perspective view, and (D) bottom perspective view of the main body cap which comprises a pressure relief mechanism. FIG. 4A is an overall cross-sectional view and FIG. 4B is an enlarged cross-sectional view of the pressure relief mechanism for explaining the action and effect of the pressure relief mechanism when the pressure rises abnormally on the primary side;

First, a pressure reducing valve A, which is one embodiment of the present invention, will be described with reference to the drawings.

1 is a perspective view of a pressure reducing valve A. FIG. FIG. 2 is a cross-sectional view of the pressure reducing valve A, where (A) is a cross-sectional view in the open state and (B) is a cross-sectional view in the closed state.

3A and 3B are diagrams illustrating the details of the valve body 9 used in the pressure reducing valve A. FIG. FIG. 3A is a front perspective view of the valve body 9 viewed from the front, and FIG. 3B is a side view of the valve body 9, that is, FIG. is a side perspective view rotated 90° at .

The valve body 9 includes, from above, a valve body screw portion 9i, a valve body cylindrical portion 9h, a valve body pressing portion 9g, a valve body shaft portion 9e, a valve body valve portion 9c, a valve body sliding portion 9d, a valve body recessed portion 9f, and a bottom portion. It is formed from a depressed portion 9j. Other than the valve body valve portion 9c, the outer diameters of the valve body threaded portion 9i, the valve body cylinder portion 9h, the valve body shaft portion 9e, and the valve body sliding portion 9d gradually increase downward. It is molded with a large diameter. The outer diameter of the valve body pressing portion 9g is formed slightly larger than the outer diameter of the valve body shaft portion 9e. The valve body valve portion 9c has a truncated cone shape, and the valve body valve portion 9c is seated on a valve seat 7 described below to close the pressure reducing valve A. As shown in FIG. An O-ring 26 is fitted in the valve body recess 9f as described below.

The pressure reducing valve A has a valve casing 1 made of synthetic resin. A first connection tube 2 and a second connection tube 3 are provided on the side surface of the valve casing 1 so as to protrude sideways and in opposite directions. Both connecting cylinders 2 and 3 are arranged laterally substantially coaxially. A primary chamber 4 is formed inside the first connecting tube 2 to serve as the fluid inflow side. On the other hand, a part of the secondary chamber 5 serving as the outflow side of the fluid is formed inside the second connecting tube 3 .

The primary chamber 4 and the secondary chamber 5 are formed so as to gradually narrow toward the inner part. A valve port 6 is formed through the upper surface of the inner part of the primary chamber 4 , and the primary chamber 4 and the secondary chamber 5 can communicate with each other through this valve port 6 . The valve port 6 is formed vertically, and its central axis is substantially orthogonal to the central axes of the first and second connecting cylinders 2 and 3 . A valve seat 7 is formed at the lower end of the opening edge of the valve port 6 .

A lower opening 8 that opens downward is provided in the lower surface of the valve casing 1 in the figure and in the intermediate portion between the first and second connecting cylinders 2 and 3 . A partition wall 12 is provided that extends upward and isolates the primary chamber 4 and the secondary chamber 5 when the pressure reducing valve A is closed. A movable piece 10 is accommodated in the lower opening 8 so as to be vertically movable by being fitted into the inner diameter of the lower opening 8 . The movable top 10 is provided with a top opening 10a that opens upward. The piece opening 10a is provided so that the inner diameter fits with the valve element sliding portion 9d of the valve element 9, and the valve element 9 is accommodated in the piece opening 10a of the movable piece 10 so as to be vertically movable. A space surrounded by the bottom of the valve body 9 and the top opening 10a serves as a relief chamber 11. As shown in FIG. The lower opening 8 and the top opening 10a are formed substantially coaxially with the valve port 6. As shown in FIG. An O-ring 27 is fitted to the side surface of the movable piece 10, and an O-ring 26 is fitted to the valve body concave portion 9f of the valve body 9. and the valve body 9 are held in a sealed state. Details of the movable top 10 will be described later with reference to FIG.

As described above, the valve body 9 can move within the top opening 10a while maintaining the sealing state between the top opening 10a and the valve body 9. As shown in FIG. Further, in the axial center of the valve body 9, there is a cylindrical valve body relief groove 9a extending upward from the bottom depression 9j to the valve body shaft part 9e, and the valve body relief groove 9a in the valve body shaft part 9e. A valve body release lateral groove 9b penetrating the valve body 9 in the left-right direction is formed in communication with the valve body. The effects of the valve body relief longitudinal groove 9a and the valve body relief lateral groove 9b will be described later.

A body cap 28 is attached to the valve casing 1 below the movable piece 10 with cap screws 31 , 31 . A cylindrical cap opening 28d that opens upward is provided in the center of the main body cap 28, and a top spring 30 is provided between the bottom surface of the cap opening 28d and the bottom surface of the movable top 10 to move the movable top 10. It is arranged to bias upward. As shown in FIG. 1, a gap 32 is provided between the movable piece 10 and the body cap 28, so that the cap opening 28d of the body cap 28 communicates with the atmosphere. Details of the body cap 28 will be described later with reference to FIG.

On the other hand, in the valve casing 1 , a governor cover 22 is attached by screws (not shown) to the opposite side (upper side in the drawing) of the lower opening 8 . At the central portion of the governor cover 22, an upper governor opening 22a penetrating vertically and a lower governor opening 22b having an opening diameter slightly larger than the opening diameter of the upper governor opening 22a are continuously provided.

An upper opening of the valve port 6 is a pressure sensing chamber 29 that communicates with the secondary chamber 5 and applies the pressure in the secondary chamber 5 to a diaphragm 17, which will be described later.

A valve mechanism M composed of a diaphragm 17, a valve body 9, and the like is incorporated in the valve port 6 so as to penetrate therethrough. The valve mechanism M is movable along the axis of the valve opening 6 .

The central portion of the diaphragm 17 is thick. A through hole through which the valve body screw portion 9i and the valve body cylindrical portion 9h pass is provided at the center of the thick portion of the diaphragm 17, and a pressure receiving plate 20 is disposed on the upper end surface of the valve body pressing portion 9g. It is sandwiched between a spring receiving plate 21 fixed to the upper end surface of the valve body pressing portion 9g by screwing with a nut 25 fitted to the valve body screw portion 9i. A peripheral portion of the diaphragm 17 is sandwiched between the lower end surface of the governor cover 22 and the upper end surface of the valve casing 1 . Since the diaphragm 17 is formed of an elastic member, the peripheral edge portion of the diaphragm 17 works as a sealing member between the governor cover 22 and the valve casing 1, and the seal between the governor cover 22 and the valve casing 1 is maintained. held. The diaphragm 17 has a flexible portion 17a located between the governor cover 22 and the spring receiving plate 21. As shown in FIG.

As described above, the governor cover 22 is formed in a two-stage cylindrical shape, and has a large-diameter lower governor opening 22b on the valve casing 1 side, and a concentric small-diameter upper governor opening 22a on the upper side in the figure. formed. The upper governor opening 22a is open upward, and a threaded portion 22c is formed at the upper end of the opening into which a pressure adjusting screw 23 is threadably incorporated. An adjusting spring 24 such as a coil spring is interposed between the pressure adjusting screw 23 and the spring receiving plate 21 to apply a biasing force to the valve mechanism M in the valve opening direction. Further, by adjusting the tightening amount of the adjustment spring 24, the valve opening amount of the valve mechanism M can be adjusted. The upper governor opening 22a and the lower governor opening 22b are substantially concentric with the valve port 6. As shown in FIG.

As described above, in the valve mechanism M, the valve body 9 and the diaphragm 17 are integrally configured via the pressure receiving plate 20 and the spring receiving plate 21 so as to be vertically movable along the central axis of the valve port 6. there is The pressure reducing valve A is closed when the valve element 9c of the valve element 9 is seated on the valve seat 7, and is opened when the valve element 9c is separated from the valve seat 7 as shown in FIG. Become.

Next, the effects of the pressure reducing valve A according to the present invention configured as described above will be described. A device (not shown) (for example, a water discharge device of a water heater) is connected to the second connection cylinder 3 via a downstream channel (not shown). When the flow of (for example, water or hot water) is stopped, the pressure reducing valve A is kept closed. This is because, as described above, the adjustment spring 24 biases the diaphragm 17 in the valve opening direction, but the pressure in the secondary chamber 5 (the pressure in the pressure sensing chamber 29) affects the valve body 9 and the diaphragm. 17 as an urging force in the valve closing direction as indicated by the arrow (1) in FIG. Here, the biasing force of the adjustment spring 24 is set so as to be smaller than the force in the valve closing direction when the flow in the downstream flow path is stopped. As indicated by the arrow (2) in 2, the pressure reducing valve A is held in the closed state by moving upward.

On the other hand, when the channel of the device is opened and the fluid flows into the downstream channel and the pressure in the secondary chamber 5 decreases, the biasing force acting on the valve element 9 and the diaphragm 17 in the valve closing direction weakens. The valve body 9 moves downward in the figure together with 17 . As a result, the valve body portion 9c of the valve body 9 is separated from the valve seat 7, and the pressure reducing valve A is opened (the state of (A) in FIG. 2). Accordingly, the fluid in the primary chamber 4 flows into the secondary chamber 5 through the valve port 6 .

If the pressure in the secondary chamber 5 rises for some reason while the pressure reducing valve A is open, the valve element 9 moves upward in the drawing together with the diaphragm 17, so that the opening of the valve opening 6 decreases. Then, pressure loss increases when the fluid passes through the valve port 6, so the pressure in the secondary chamber 5 decreases. Due to the action of the pressure reducing valve A, the pressure on the side of the secondary chamber 5 is maintained below a predetermined value.

When the device switches from the state in which the flow path is open to the state in which it is closed, the flow of fluid in the pressure reducing valve A (primary chamber 4 and secondary chamber 5) stops, and the pressure in the secondary chamber 5 rises. . Then, the diaphragm 17 rises due to the pressure in the secondary chamber 5, and the valve element 9 rises together with the diaphragm 17, so that the pressure reducing valve A switches from the open state to the closed state.

As described above, when the pressure reducing valve A is open, the opening degree of the valve port 6 is adjusted by vertical movement of the valve body 9 and the diaphragm 17, and the pressure on the side of the secondary chamber 5 is reduced to a predetermined value or less. The valve is maintained and closed when the flow path is closed.

Next, the pressure relief mechanism that characterizes the present invention will be described with reference to the drawings. In the pressure reducing valve A, when water hammer occurs in the water pipe on the upstream side or the pipe line freezes, the pressure of the water hammer and the pressure due to freezing expansion of water are applied to the primary chamber 4 of the valve casing 1, The pressure may damage the interior of the primary chamber 4 . In such a case, this pressure relief mechanism is intended to alleviate the pressure generated in the primary chamber 4 and prevent the primary chamber 4 from being damaged.

FIG. 4 is a diagram for explaining the details of the movable piece 10 that constitutes the pressure relief mechanism provided in the pressure reducing valve A. As shown in FIG. 4A is a top perspective view from above, FIG. 4B is a front perspective view from the front, FIG. 4C is a side perspective view from the side, (D) of FIG. 4 is a bottom transparent view.

The movable top 10 is composed of a top upper end portion 10g, a top concave portion 10f, a top body portion 10d, and a top base portion 10c. The upper end portion 10g of the top has a cylindrical shape with a small height at the upper end, and a truncated cone shape with a downwardly expanding diameter below the upper end. The top concave portion 10f and the top main body portion 10d are cylindrical, and the outer diameter of the top main body portion 10d is substantially the same as the outer diameter of the bottom of the truncated conical portion of the top top end portion 10g. The top base portion 10c has a horizontally elongated substantially elliptical shape extending in the left-right direction, and top through-holes 10e, 10e are provided in the left and right sides of the top main body portion 10d so as to pass through in the vertical direction. In addition, a top opening 10a is provided in the central portion of the top to open upward from the top end 10g to the top base 10c. The O-ring 27 is fitted in the top concave portion 10f as described above. A top spring mounting portion 10h is provided at the center of the bottom of the top base portion 10c. A pressure relief slit 10b is provided in the upper inner diameter portion of the top upper end portion 10g.

FIG. 5 is a diagram illustrating the details of the body cap 28 that constitutes the pressure relief mechanism provided in the pressure reducing valve A. As shown in FIG. 5A is a top perspective view from above, FIG. 5B is a front perspective view from the front, FIG. 5C is a side perspective view from the side, (D) of FIG. 5 is a bottom transparent view.

The main body cap 28 includes a cap base portion 28a having substantially the same shape and size as the top base portion 10c, a cap main body portion 28c provided below the center of the cap base portion 28a, and a cap main body portion 28c in the cap base portion 28a. On the other hand, it is formed from cap guides 28b, 28b extending upward on the left and right sides. A cap opening 28d that opens upward from the cap base portion 28a to the cap body portion 28c is provided in the center. Further, the cap guides 28b, 28b are provided with cap through holes 28e, 28e that penetrate the cap guides 28b, 28b in the vertical direction. The cap guides 28b, 28b and the cap main body 28c are cylindrical. The outer diameter of the cap guide 28b is slightly smaller than the inner diameter of the piece through hole 10e, and as shown in FIG. Let Then, the cap screws 31, 31 are inserted from below into the cap through holes 28e, 28e of the cap guides 28b, 28b and screwed to assemble the movable piece 10 and the body cap 28 to the valve casing 1.

As described above, the top spring 30 is arranged between the top spring mounting portion 10h of the movable top 10 and the bottom portion of the cap opening 28d so as to urge the movable top 10 upward. In normal operation, as shown in FIG. 2, pressure is applied to the upper inner diameter portion of the top end portion 10g of the movable top 10 above the O-ring 26 fitted in the valve body recessed portion 9f of the valve body 9. An escape slit 10b is arranged. Therefore, the opening 10a of the movable piece 10 and the valve body 9 are kept in a sealed state by the O-ring 26, and the primary chamber 4 and the opening 10a are separated from each other.

Next, the effects of the pressure relief mechanism of the pressure reducing valve A according to this embodiment configured as described above will be described.

FIG. 6 is a diagram for explaining the effect of the pressure relief mechanism of the pressure reducing valve A when the primary chamber 4 is abnormally pressurized due to water hammer, freezing expansion of water, or the like. 6A is an overall cross-sectional view of the pressure reducing valve A, and FIG. 6B is an enlarged cross-sectional view of the pressure relief mechanism.

When the pressure in the primary chamber 4 rises abnormally as indicated by arrow (1) in FIG. 6A, pressure is first applied to move the valve body 9 upward as indicated by arrow (2). As a result, when the pressure reducing valve A is open, the valve body valve portion 9c of the valve body 9 is seated on the valve seat 7 to close the valve. Further, when the pressure in the primary chamber 4 increases, pressure is applied to the movable top 10 as indicated by arrow (3). Then, the movable top 10 moves downward as indicated by an arrow (3) against the biasing force of the top spring 30. As shown in FIG. As shown in FIG. 6B, when the pressure relief slit 10b of the movable piece 10 moves below the O-ring 26 fitted in the valve body concave portion 9f of the valve body 9, the arrow in FIG. As shown in (5), the primary chamber 4 and the piece opening 10a communicate with each other through the pressure relief slit 10b, and the volume of the relief chamber 11 surrounded by the piece opening 10a and the bottom of the valve body 9 increases. Therefore, the volume of the primary chamber 4 is increased, and the abnormally increased pressure in the primary chamber 4 is relieved. The pressure in the primary chamber 4 that has flowed into the relief chamber 11 flows through the valve relief longitudinal groove 9a and the valve relief lateral groove 9b of the valve body 9 as indicated by arrows (6) in FIG. It can escape to chamber 5. Therefore, even if the pressure of the water hammer or the pressure due to freezing and expansion of water is applied to the primary chamber 4, the pressure generated in the primary chamber 4 can be alleviated to prevent damage to the primary chamber 4. of.

As described above, in the pressure reducing valve A according to the present embodiment, by adding a simple configuration in which the movable piece 10 is added below the valve body 9, freezing destruction of the primary chamber 4 can be prevented. The manufacturing cost can be suppressed, and an increase in the size of the pressure reducing valve A can be suppressed, so that the pressure reducing valve A can be made compact.

Here, the pressure reducing valve A is an example of a pressure reducing valve, the primary chamber 4 is an example of a primary chamber, the secondary chamber 5 is an example of a secondary chamber, the valve port 6 is an example of a valve port, and the valve The body 9 is an example of a valve body, the valve seat 7 is an example of a valve seat, and the space from the upper governor opening 22a to the lower governor opening 22b and the pressure sensing chamber 29 is an example of a first opening. , the diaphragm 17 is an example of a diaphragm, the adjusting spring 24 is an example of a first biasing member, the pressure sensing chamber 29 is an example of a pressure receiving chamber, the movable top 10 is an example of a movable top, and the top opening. The portion 10a is an example of a second opening, the relief chamber 11 is an example of a relief chamber, the top spring 30 is an example of a second biasing member, and the pressure relief slit 10b is an example of a pressure relief slit. , and the valve body relief longitudinal groove 9a and the valve body relief lateral groove 9b are examples of the communication path.

Although the embodiments of the present invention have been described in detail above, these are only examples, and the present invention is not to be construed in any limited way by the specific descriptions in such embodiments. It can be implemented in embodiments with various changes, modifications, improvements, etc. based on knowledge, and as long as such embodiments do not depart from the spirit of the present invention, all are within the scope of the present invention. should be understood to be included in the

For example, if the abnormal pressurization of the primary chamber 4 can be alleviated by increasing the volume of the relief chamber 11, the valve relief longitudinal groove 9a and the valve relief lateral groove 9b of the valve body 9 are not necessarily required.

A. Pressure reducing valve 1. Valve casing 4. Primary chamber 5. Secondary chamber 6. Valve opening 7. Valve seat 9. Valve body 10. Movable piece 10 b. Relief chamber 17... Diaphragm 22... Governor cover 24... Adjusting spring 28... Main body cap 30... Top spring

Claims (2)

a primary room;
a secondary chamber communicating with the primary chamber via a valve port;
a valve body movable to change the opening degree of the valve opening;
a valve seat on which the valve element formed in the valve port is seated;
A first opening is provided on the upper end side of the valve body, and a diaphragm closing the first opening;
a pressure receiving chamber provided on the lower surface of the diaphragm and communicating with the secondary chamber;
A pressure reducing valve comprising a first biasing member integrally biasing the diaphragm and the valve body in a direction to open the valve port,
A second opening is provided in the upper portion of the valve body, and the second opening fits the lower end of the valve body so that the lower end surface of the valve body and the second opening are fitted. A movable piece that forms an escape chamber consisting of an opening of and is movable in the vertical direction;
a pressure relief slit provided at the upper end of the movable piece and communicating with the relief chamber when the movable piece moves downward;
and a second urging member for urging the movable piece in a direction in which the pressure relief slit of the movable piece is closed. 2. The pressure reducing valve according to claim 1, wherein the valve body is provided with a communication passage that communicates the relief chamber and the secondary chamber.

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