JP2010186353A - Pressure reducing valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure reducing valve which suppresses the occurrence of any closed valve failure due to dusts more than a conventional manner. <P>SOLUTION: The pressure reducing valve includes: a primary passage; a secondary passage; and a valve mechanism having a water stopping function for variably adjusting the passage area of a boundary section between the primary passage and the secondary passage, and the valve mechanism includes; a valve seat arranged at the boundary section between the primary passage and the secondary passage; a valve body which is connected to one end of a piston head which receives a primary pressure, and opposite to the valve seat; and a diaphragm which is connected to the other end of the piston head, and receives a secondary pressure, wherein the contact section of the valve body and the valve seat includes a double annular protrusion. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a pressure reducing valve used in a water-circulating device.

A primary side passage, a secondary side passage, and a valve mechanism having a water stop function that variably adjusts the flow passage area at the boundary between the primary side passage and the secondary side passage. A valve seat disposed at the boundary with the secondary passage, a valve body connected to one end of the piston head that receives the primary pressure and opposed to the valve seat, and connected to the other end of the piston head and secondary A pressure reducing valve having a diaphragm for receiving pressure is disclosed in Patent Document 1 and the like.
The pressure reducing valve opens when the water discharge device connected to the secondary passage is opened, supplies the secondary pressure reduced to the primary pressure to the water discharge device, and closes when the water discharge device is closed. It is comprised so that the water supply to a water discharging apparatus may be stopped.
Conventionally, the contact portion between the valve body and the valve seat of the pressure reducing valve has a single annular projection formed on the valve seat.

JP 2006-146832 A

A strainer is installed upstream of the pressure reducing valve to prevent dust such as iron powder from flowing into the pressure reducing valve, but fine dust passes through the mesh of the strainer, and the flow rate of the valve element is low. Sometimes it is trapped between the single annular protrusion and the valve body facing the annular protrusion and adheres to the valve body, or when the pressure reducing valve closes, the single annular protrusion and the valve facing the annular protrusion There was a possibility of being caught between the body. When dust is interposed between the single annular protrusion and the valve body facing the annular protrusion when the valve is closed, there is a possibility that a valve closing failure may be caused.
The present invention has been made in view of the above problems, and has a water stop function for variably adjusting the flow area at the boundary between the primary side passage, the secondary side passage, and the primary side passage and the secondary side passage. A valve mechanism, a valve seat disposed at a boundary portion between the primary side passage and the secondary side passage, a valve body connected to one end of a piston head that receives the primary pressure and facing the valve seat; An object of the present invention is to provide a pressure reducing valve having a diaphragm connected to the other end of the piston head and receiving a secondary pressure, in which the occurrence of valve closing failure due to dust is suppressed compared to the conventional one. And

In order to solve the above-mentioned problems, in the present invention, a valve having a water stop function for variably adjusting the flow area of the primary side passage, the secondary side passage, and the boundary between the primary side passage and the secondary side passage. A valve mechanism, a valve seat disposed at a boundary portion between the primary side passage and the secondary side passage, a valve body coupled to one end of a piston head that receives the primary pressure and facing the valve seat; A pressure reducing valve having a diaphragm connected to the other end of the piston head and receiving a secondary pressure, wherein a contact portion between the valve body and the valve seat has a double annular projection. .
Since the water passing through the annular gap between the valve seat and the valve body flows radially outwardly in the annular gap, the valve body closes at a low flow rate with a small opening of the valve element. If dust is trapped between the annular protrusion and the valve body or valve seat facing the annular protrusion, the dust is between the inner annular protrusion and the valve body or valve seat facing the annular protrusion. The possibility of being caught between the outer annular projection and the valve body or the valve seat facing the annular projection is low. Therefore, even if the inner annular protrusion has a valve closing failure, the outer annular protrusion is likely to close normally. As a result, the occurrence of valve closing failure due to dust is suppressed as compared to the conventional case.

In a preferred embodiment of the present invention, the double annular protrusion is formed on the valve seat.
In a preferred embodiment of the present invention, the inner annular protrusion is formed on the valve body, and the outer annular protrusion is formed on the valve seat.
A double annular protrusion may be formed on the valve seat, an inner annular protrusion may be formed on the valve body, and an outer annular protrusion may be formed on the valve seat, or a double annular protrusion may be formed on the valve body. You may do it.
Since the valve seat is generally made of hard metal or resin, and the valve body is generally made of flexible rubber, if the inner annular protrusion is formed on the valve body and the inner annular protrusion is easily elastically deformed, the valve is closed. When the dust is caught between the inner annular projection and the valve seat facing the annular projection, the outer annular projection contacts the valve body or valve seat facing the annular projection. The time until the seal portion is formed in contact is shortened, and an increase in the secondary pressure when the valve is closed can be suppressed. On the other hand, the durability of the annular protrusions can be enhanced by forming the annular protrusions on a metal or resin valve seat that is stronger than rubber.

In a preferred embodiment of the present invention, the height of the outer annular protrusion is less than the height of the inner annular protrusion.
If the height of the outer annular protrusion is less than the height of the inner annular protrusion, the valve element or valve faces the outer annular protrusion and the annular protrusion when the valve body is open at low flow rate or when the valve is closed. The possibility that dust is trapped between the seats can be reduced.

In a preferred aspect of the present invention, the pressure reducing valve includes a body, a cylinder formed by a part of the body, a piston head that reciprocates in the cylinder, and extends from one end face of the piston head and extends from one end of the cylinder to the outside of the cylinder. A first piston rod projecting toward the valve, a valve seat formed by the one end of the cylinder, a valve body fixed to one end of the first piston rod projecting out of the cylinder and facing the valve seat, and a first piston on the cylinder peripheral wall An opening formed in a portion facing the rod, a second piston rod extending from the other end face of the piston head and projecting from the other end of the cylinder to the outside of the cylinder, and an end projecting from the other end of the cylinder of the second piston rod It is formed by a diaphragm with a fixed center and a part of the body, facing the diaphragm, the diaphragm, cylinder, and piston head. A diaphragm case that cooperates with the diaphragm to form a pressure sensing chamber, a spring that presses the diaphragm toward the pressure sensing chamber, a spring case that houses the spring and cooperates with the diaphragm case to sandwich the periphery of the diaphragm, and a piston A seal member that is accommodated in the circumferential groove of the head and seals a sliding contact portion between the piston head and the inner peripheral surface of the cylinder, and the body includes a valve inlet that communicates with the opening of the cylinder peripheral wall, a valve seat, and a valve body A valve outlet that communicates with the annular gap formed between the valve inlet and the annular gap to form a primary passage, and the annular gap and the valve outlet The flow path therebetween forms a secondary side passage, and the pressure sensitive chamber communicates with the secondary side passage.
The pressure reducing valve configured as described above is less likely to cause a valve closing failure due to dust than in the past.

According to the present invention, a primary side passage, a secondary side passage, and a valve mechanism having a water stop function for variably adjusting a flow passage area at a boundary portion between the primary side passage and the secondary side passage are provided. A valve seat disposed at the boundary between the side passage and the secondary passage, a valve body connected to one end of the piston head receiving the primary pressure and facing the valve seat, and connected to the other end of the piston head. In addition, there is provided a pressure reducing valve that has a diaphragm that receives a secondary pressure, and in which the occurrence of valve closing failure due to dust is suppressed as compared with the conventional pressure reducing valve.

It is sectional drawing of the pressure reducing valve which concerns on the Example of this invention. It is an enlarged partial sectional view of a valve seat with which a pressure-reduction valve concerning an example of the present invention is provided, and a valve element. It is an expanded partial sectional view of the modification of the valve seat and valve body with which the pressure-reduction valve concerning other examples of the present invention is provided. It is an expanded partial sectional view of the modification of the valve seat and valve body with which the pressure-reduction valve concerning other examples of the present invention is provided.

A pressure reducing valve according to an embodiment of the present invention will be described.
As shown in FIG. 1, the pressure reducing valve 1 includes a body 10 made of resin. A part of the body 10 forms a cylinder 11. The pressure reducing valve 1 includes a piston head 12 that reciprocally slides in the cylinder 11, a first piston rod 13 that extends from one end surface of the piston head 12 and protrudes from one end of the cylinder 11 to the outside of the cylinder 11, and the one end of the cylinder 11. An annular valve seat 14 formed by the valve body 15, a valve body 15 fixed to one end of the first piston rod 13 protruding from the cylinder 11 and facing the valve seat 14, and a first piston rod 13 on the peripheral wall of the cylinder 11. An opening 16 formed in the part, a second piston rod 17 extending from the other end face of the piston head 12 and projecting out of the cylinder 11 from the other end of the cylinder 11, and projecting from the other end of the cylinder 11 of the second piston rod 17 The diaphragm 18 is formed by a diaphragm 18 having a central portion fixed to one end thereof and a part of the body 10, and is opposed to the diaphragm 18. A diaphragm case 20 that forms a pressure-sensitive chamber 19 in cooperation with the ram 18, the cylinder 11, and the piston head 12, a spring 21 that presses the diaphragm 18 toward the pressure-sensitive chamber 19, a spring 21 that houses the diaphragm 21, and the diaphragm case 20 And a spring case 22 that sandwiches the peripheral edge of the diaphragm 18 and an O-ring 23 that is received in the peripheral groove of the piston head 12 and seals the sliding contact portion between the piston head 12 and the inner peripheral surface of the cylinder 11. ing.

The body 10 includes a valve inlet 24 that communicates with an annular gap S formed between the valve seat 14 and the valve body 15 via the opening 16 in the peripheral wall of the cylinder 11 and the internal space of the cylinder 11, and the valve seat 14. And a valve outlet 25 communicating with an annular gap S formed between the valve body 15 and the valve body 15.
The flow path between the valve inlet 24 and the annular gap S forms a primary side passage 26, and the flow path between the annular gap S and the valve outlet 25 forms a secondary side passage 27. The pressure chamber 19 communicates with the secondary side passage 27.
The valve body 15 is made of rubber, and the surface facing the valve seat 14 forms a flat surface.
As shown in FIG. 2, the valve seat 14 has double annular protrusions 14a and 14b disposed concentrically having a semicircular cross section. The height h of the outer annular protrusion 14b is set to be less than the height H of the inner annular protrusion 14a. Double annular seal portions 14a ′ and 14b ′ are formed by the annular protrusions 14a and 14b coming into contact with the opposing valve body 15.

The cylinder 11, the piston head 12, the first piston rod 13, the valve seat 14, the valve body 15, the second piston rod 17, the diaphragm 18, and the spring 21 cooperate with each other with the primary side passage 26 and the secondary side passage 27. The valve mechanism 28 having a water stop function for variably adjusting the flow path area of the boundary portion S is formed.
The valve inlet 24 of the pressure reducing valve 1 is connected to a water pipe (not shown) via a strainer and a check valve (not shown), and the valve outlet 25 of the pressure reducing valve 1 is connected to a hot water storage tank of a water heater (not shown). Yes. The hot water storage tank of the water heater is connected to a water discharge device (not shown) such as a shower head or a bathtub water discharge port.

The operation of the pressure reducing valve 1 will be described.
When the water discharge device is closed and the water and hot water in the flow path downstream of the pressure reducing valve 1 are stopped, the pressure reducing valve 1 is closed.
When the water discharge device is opened, the secondary pressure of the pressure reducing valve 1 (water pressure in the secondary side passage 27) decreases. As a result, the urging force in the valve closing direction due to the secondary pressure applied to the diaphragm 18 decreases, the valve body 15 is separated from the valve seat 14 by the urging force in the valve opening direction by the spring 21, and the pressure reducing valve 1 is opened. I speak. When tap water flows through the annular gap S formed between the valve body 15 and the valve seat 14, a pressure loss occurs and the tap water is depressurized.
Since the secondary side passage 27 and the pressure sensitive chamber 19 communicate with each other, the secondary pressure of the pressure reducing valve 1, which is the tap water pressure in the secondary side passage 27, is applied to the diaphragm 18. The primary pressure of the pressure reducing valve 1, which is tap water pressure in the primary passage 26, is pressure-sensitive by the O-ring 23 housed in the circumferential groove of the piston head 12 sealing the sliding contact portion between the piston head 12 and the cylinder 11. It is not transmitted to the chamber 19 and is not applied to the diaphragm 18.

When the secondary pressure rises for some reason, the diaphragm 18 is elastically deformed in the direction away from the valve seat 14 against the biasing force of the spring 21, and the second piston rod 17 fixed to the diaphragm 18 is eventually moved into the piston head 12, The first piston rod 13 follows the diaphragm 18 and moves to the diaphragm 18 side, and the valve body 15 approaches the valve seat 14. As a result, the annular gap S between the valve seat 14 and the valve body 15 is narrowed, and the pressure loss when tap water passes through the annular gap S increases. As a result, the secondary pressure decreases. Therefore, in the pressure reducing valve 1, the secondary pressure is maintained below a predetermined value.

When the water discharge device is closed, the flow velocity in the pressure reducing valve 1 rapidly decreases toward zero. Along with the rapid decrease in the flow velocity, the differential pressure between the primary pressure (water pressure in the primary side passage 26) and the secondary pressure (water pressure in the secondary side passage 27) decreases rapidly. As a result, the urging force in the valve closing direction due to the secondary pressure applied to the diaphragm 18 increases rapidly, the valve element 15 moves toward the valve seat 14 against the urging force of the spring 21, and the inner annular protrusion 14a is moved. Abutting to form an annular seal portion 14a ', the annular gap S is closed. As a result, the pressure reducing valve 1 is closed.
When the pressure reducing valve 1 is closed while the flow velocity in the pressure reducing valve 1 is rapidly decreasing toward zero, the secondary pressure after the valve closing is maintained at a value lower than the primary pressure. As a result, it is possible to prevent the occurrence of an unfavorable situation such as opening of the relief valve attached to the water heater after the valve is closed.
When the amount of increase in the secondary pressure until the annular seal portion 14a ′ is formed is large, the outer annular protrusion 14b also contacts the valve body 15 to form the annular seal portion 14b ′. When the amount of increase in the secondary pressure until the annular seal portion 14a ′ is formed is small, the outer annular protrusion 14b does not contact the valve body 15, and the annular seal portion 14b ′ is not formed.

A strainer is disposed upstream of the pressure reducing valve 1 to prevent dust such as iron powder from flowing into the pressure reducing valve 1. However, fine dust passes through the mesh of the strainer and the opening of the valve body 15 is increased. Captured between the annular protrusions 14a, 14b and the valve body 15 at a small low flow rate and attached to the valve body 15, or captured between the annular protrusions 14a, 14b and the valve body 15 when the pressure reducing valve 1 is closed. There is a possibility that. Since the water passing through the annular gap S between the valve seat 14 and the valve body 15 flows radially toward the radially outer side of the annular gap S, dust is formed between the inner annular protrusion 14 a and the valve body 15. The possibility of being caught between the outer annular projections 14b and the valve body 15 is low.
When dust is interposed between the annular protrusion 14a and the valve body 15 when the pressure reducing valve 1 is closed, formation of the annular seal portion 14a ′ is inhibited. In this case, water having a flow velocity that is rapidly decreasing toward zero flows into the secondary side passage 27 through the poorly closed annular gap S, and the secondary pressure rises and is applied to the diaphragm 18. The urging force in the valve closing direction due to the water pressure increases, the valve body 15 further moves toward the valve seat 14, contacts the outer annular protrusion 14b, forms an annular seal portion 14b ', and closes the annular gap S To do. As a result, the pressure reducing valve 1 is closed. Even in this case, since the pressure reducing valve 1 is closed while the flow velocity in the pressure reducing valve 1 is rapidly decreasing toward zero, the secondary pressure after the valve closing is maintained at a value lower than the primary pressure. Occurrence of an unfavorable situation such as opening of a relief valve attached to the water heater is prevented.
As can be seen from the above description, in the pressure reducing valve 1 according to the present embodiment, even if the inner annular protrusion 14a becomes poorly closed due to dust, the outer annular protrusion 14b is likely to close normally. As a result, the occurrence of valve closing failure due to dust is suppressed as compared to the conventional case.
Since the height h of the outer annular protrusion 14b is set to be less than the height H of the inner annular protrusion 14a, the outer annular protrusion 14b and the valve There is a low possibility that dust is trapped between the valve body 15 facing the annular protrusion. As a result, the possibility of dust being interposed between the outer annular projection 14b and the valve body 15 at the time of valve closing is further reduced, and the occurrence of valve closing failure due to dust is further suppressed as compared to the conventional case.
The durability of the annular protrusions 14a and 14b can be increased by forming the annular protrusions 14a and 14b on a metal or resin valve seat having high strength.

As shown in FIG. 3, an inner annular protrusion 15 a may be formed on the valve body 15, and an outer annular protrusion 14 c may be formed on the valve seat 14. If the inner annular protrusion 15a is formed on the rubber flexible valve body 15 so that the inner annular protrusion 15a is easily elastically deformed, the inner annular protrusion 15a and the valve seat 14 are closed when the valve is closed. The time from when the dust is sandwiched between the outer annular protrusion 14c to the valve body 15 and the formation of the outer annular seal portion is shortened, and the secondary pressure at the time of closing the valve is reduced. The rise can be suppressed.
As shown in FIG. 4, the valve body 15 may be formed with an inner annular protrusion 15a and an outer annular protrusion 15b, and the valve seat 14 may be a flat surface.
Three or more annular projections may be formed on the valve seat 14 and / or the valve body 15 in total.

  The present invention is widely applicable to pressure reducing valves.

DESCRIPTION OF SYMBOLS 1 Pressure reducing valve 10 Body 11 Cylinder 12 Piston head 13 1st piston rod 14 Valve seat 14a, 14b, 14c, 15a, 15b Annular protrusion 14a ', 14b' Annular seal part 15 Valve body 17 2nd piston rod 18 Diaphragm 19 Pressure sensitive Chamber 20 Diaphragm case 21 Spring 22 Spring case 23 O-ring 24 Valve inlet 25 Valve outlet 26 Primary side passage 27 Secondary side passage 28 Valve mechanism

Claims (6)

A primary side passage, a secondary side passage, and a valve mechanism having a water stop function that variably adjusts the flow passage area at the boundary between the primary side passage and the secondary side passage. A valve seat disposed at the boundary with the secondary passage, a valve body connected to one end of the piston head that receives the primary pressure and opposed to the valve seat, and connected to the other end of the piston head and secondary A pressure reducing valve having a diaphragm for receiving pressure, and a contact portion between the valve body and the valve seat having double annular protrusions. The pressure reducing valve according to claim 1, wherein the double annular protrusion is formed on the valve seat. 2. The pressure reducing valve according to claim 1, wherein an inner annular protrusion is formed on the valve body, and an outer annular protrusion is formed on the valve seat. The pressure reducing valve according to claim 1, wherein the double annular protrusion is formed on the valve body. The pressure reducing valve according to any one of claims 1 to 4, wherein the height of the outer annular protrusion is less than the height of the inner annular protrusion. A body, a cylinder formed by a part of the body, a piston head that reciprocally slides in the cylinder, a first piston rod that extends from one end surface of the piston head and projects out of the cylinder from one end of the cylinder, and the cylinder A valve seat formed by one end; a valve body fixed to one end of the first piston rod protruding out of the cylinder and facing the valve seat; an opening formed at a portion facing the first piston rod of the cylinder peripheral wall; A second piston rod extending from the other end face of the piston head and projecting out of the cylinder from the other end of the cylinder; a diaphragm having a center fixed to one end projecting from the other end of the cylinder of the second piston rod; Diaphragm that is formed by a portion and faces the diaphragm to form a pressure sensitive chamber in cooperation with the diaphragm, cylinder, and piston head A spring that presses the diaphragm toward the pressure-sensitive chamber, a spring case that houses the spring and cooperates with the diaphragm case to sandwich the peripheral edge of the diaphragm, and is accommodated in the circumferential groove of the piston head and is accommodated in the piston head and cylinder A seal member that seals a sliding contact portion with the inner peripheral surface, and the body communicates with a valve inlet that communicates with the opening of the cylinder peripheral wall and an annular gap formed between the valve seat and the valve body. A flow path between the valve inlet and the annular gap forms a primary-side passage, and a flow path between the annular gap and the valve outlet forms a secondary-side passage. 6. The pressure reducing valve according to claim 1, wherein the pressure sensing chamber communicates with the secondary passage.

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