JP2011059838A - Pressure reducing valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure reducing valve for, when a primary pressure rises in closing a pressure reducing valve, reducing the primary pressure without directly draining water from the primary side passage to the outside of the pressure reducing valve. <P>SOLUTION: The pressure reducing valve is provided with: a primary side passage; a secondary side passage; a first valve mechanism having a cylinder, a piston inserted into the cylinder so as to slide, a first valve body fixed to one end of the piston, a diaphragm fixed to the other end of the piston for receiving a secondary pressure, and a first spring for biasing the diaphragm to the valve opening direction of the first valve body, and for variably adjusting the channel area of a first communicating part between the primary side passage and the secondary side passage; and a second valve mechanism having a second valve body and a second spring for biasing the second valve body to a valve closing direction, and for opening/closing a second communicating part between the primary side passage and the secondary side passage. The second valve mechanism is stored in the piston of the first valve mechanism. When the first communicating part between the first primary side passage and the secondary side passage is closed by the first valve mechanism, the second communicating part between the primary side passage and the secondary side passage is opened by the second valve mechanism. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a pressure reducing valve used in a water heater having a can.

In the patent document 1, the applicant of the present invention discloses a primary side passage, a secondary side passage, a piston slidably inserted in the cylinder, a valve body fixed to one end of the piston, and the other end of the piston. A diaphragm that receives the secondary pressure, and a spring that biases the diaphragm in the valve opening direction, and the flow area of the communication portion between the primary side passage and the secondary side passage is variable. Disclosed is a pressure reducing valve assembly comprising: a pressure reducing valve with a regulating valve mechanism; a drain valve disposed upstream of the pressure reducing valve with respect to fluid flow; and a check valve disposed upstream of the drain valve. .
In the above pressure reducing valve assembly, when the primary pressure of the pressure reducing valve rises beyond the appropriate range due to a water hammer or the like when the pressure reducing valve is closed, the pressure reducing valve assembly is directly connected to the outside of the pressure reducing valve through the drain valve. By draining high-pressure tap water into the water, pressure resistance performance of the primary side passage, water stop performance of the engagement portion between the valve body and the valve mechanism forming the primary side passage and the secondary side passage, communication portion of the valve body The performance of the pressure reducing valve, which is a set of opening adjustment performance, etc. is maintained well.

JP 2006-048549 A

The pressure reducing valve assembly disclosed in Patent Document 1 is used as a component part of a water heater having a can body. The hot water heater having a can body is for discharging high-pressure steam or hot water in the hot water storage tank to the hot water heater when the internal pressure of the hot water storage tank arranged on the downstream side of the pressure reducing valve increases beyond an appropriate value. Has a relief valve. Therefore, when the pressure reducing valve assembly disclosed in Patent Document 1 is used as a component of a water heater having a can body, in addition to a drain pipe connecting a relief valve and a drain outlet at a place where the water heater is installed, a pressure reducing valve assembly It also becomes necessary to dispose a drainage pipe that connects the three-dimensional drainage valve and the drainage port at the place where the water heater is installed. As a result, there arises a problem that the number of drain pipes is increased as compared with the case of using a conventional pressure reducing valve assembly that does not include a drain valve.
The present invention has been made in view of the above problems, and includes a primary side passage, a secondary side passage, a cylinder slidably inserted in the cylinder, a valve body fixed to one end of the piston, and a piston. A flow path area of a communication portion between the primary side passage and the secondary side passage, having a diaphragm fixed to the other end and receiving a secondary pressure, and a spring for biasing the diaphragm in the valve opening direction And a valve mechanism that variably adjusts the primary pressure when the primary pressure rises beyond the appropriate range when the pressure reducing valve is closed, without draining directly from the primary side passage to the outside of the pressure reducing valve. An object of the present invention is to provide a pressure reducing valve capable of reducing the pressure.

In order to solve the above-mentioned problems, in the present invention, a primary side passage, a secondary side passage, a piston that is slidably inserted in the cylinder, the cylinder, and a first valve body and a piston that are fixed to one end of the piston A diaphragm that is fixed to the other end of the valve and receives the secondary pressure, and a first spring that urges the diaphragm in the valve opening direction of the first valve body, and includes a first spring between the primary side passage and the secondary side passage. A pressure reducing valve having a first valve mechanism that variably adjusts the flow passage area of the series passage portion, and includes a second valve body and a second spring that biases the second valve body in a valve closing direction. A second valve mechanism that opens and closes the second communication portion between the side passage and the secondary passage, and the second valve mechanism is accommodated in a piston of the first valve mechanism, and the first valve mechanism is primary When the first series passage between the side passage and the secondary passage is closed, the second valve mechanism is connected to the primary passage and the secondary passage with a predetermined primary pressure. Providing a pressure reducing valve, characterized in that opening the second communicating portion between the side passage.
In the pressure reducing valve according to the present invention, when the primary pressure rises when the first valve mechanism closes the first communication portion between the primary side passage and the secondary side passage, the primary pressure maintains the performance of the pressure reducing valve. Since the second valve mechanism opens the second communication portion between the primary side passage and the secondary side passage before exceeding the upper limit value appropriate for the primary pressure, the primary pressure is diluted by the secondary pressure and reduced. As a result, the performance of the pressure reducing valve is maintained favorably. In the pressure reducing valve according to the present invention, when the primary pressure rises when the valve is closed, before the primary pressure exceeds the upper limit appropriate for maintaining the performance of the pressure reducing valve without draining directly from the primary side passage to the outside of the pressure reducing valve. The primary pressure can be reduced.
Since the pressure reducing valve according to the present invention is used as a component of a water heater having a can body, the second valve mechanism opens the second communication portion between the primary side passage and the secondary side passage, and then the primary valve When the secondary pressure rises beyond the appropriate range due to the application of pressure, the relief valve of the water heater opens to open the secondary pressure to the external environment. As a result, after the second valve mechanism opens the second communication portion, occurrence of a situation in which the primary pressure rises above the upper limit appropriate for maintaining the performance of the pressure reducing valve is prevented.
A second valve mechanism that opens and closes the second communication portion between the primary side passage and the secondary side passage is accommodated in the piston of the first valve mechanism, so that the second valve mechanism is disposed outside the body of the pressure reducing valve. There is no need to install the second valve mechanism, and an increase in the size of the pressure reducing valve due to the provision of the second valve mechanism is suppressed.

In a preferred embodiment of the present invention, the diaphragm forms a part of the surrounding wall of the pressure sensing chamber that communicates with the secondary passage, and the second communicating portion is a communicating portion between the primary passage and the pressure sensing chamber. is there.
The portion of the first valve mechanism near the diaphragm generally forms a large-diameter piston head that slides on the cylinder, and the portion of the first valve mechanism near the first valve body generally forms a small-diameter piston rod. Therefore, from the viewpoint of ease of work, it is desirable that the second valve mechanism is housed in a portion near the diaphragm of the piston of the first valve mechanism that forms a large-diameter piston head. In this case, the second communication part is a communication part between the primary side passage and the pressure sensing chamber.

It is a circuit diagram of a water heater having a can having a pressure reducing valve according to an embodiment of the present invention. 1 is a structural diagram of a pressure reducing valve according to an embodiment of the present invention.

A pressure reducing valve according to an embodiment of the present invention will be described.
As shown in FIG. 1, a water heater A having a can body is disposed sequentially from the upstream to the downstream with respect to a first pipe 1 through which water or hot water flows during hot water supply and a water flow through the first pipe 1 during hot water supply. A check valve 2a connected to one pipe, a pressure reducing valve 3, a hot water storage tank 4 having a heater, a relief valve 5 having a negative pressure operating function, a check valve 2b, and a hot water mixing valve 6 are provided. The portion of the first pipe 1 extending from the pressure reducing valve 3 is connected to the lower end of the hot water storage tank 4, the portion of the first pipe 1 extending from the hot water storage tank 4 extends from the top of the hot water storage tank 4, and the hot water storage tank 4 of the first pipe 1. A drain valve 7 is connected to a portion extending in the vicinity of the lower end, and further branched from a portion extending between the pressure reducing valve 3 and the hot water storage tank 4 of the first pipe 1 and connected to the cold water inlet of the hot water mixing valve 6. Regarding the second pipe 8 through which water flows during hot water supply and the water flow through the second pipe 8 during hot water supply Serial and a check valve 2c connected to the second pipe 8 is disposed upstream of the hot and cold water mixing valve 6. The first pipe 1 extends further downstream from the hot / cold water mixing valve 6 and is connected to a water discharge device 200 such as a shower head or a bathtub water discharge port. An electromagnetic valve 9, check valves 2d and 2d, and an edge cut valve 10 are disposed in the middle of the first pipe 1 extending from the hot and cold mixing valve 6 to the bathtub. The relief valve 5 is connected to the drain port of the drain valve 7 via the drain hose 1 ′. Below the drain valve 7, a drain port of a water heater installation location (not shown) is disposed.

In the water heater A, when hot water is supplied, tap water flows into the lower part of the hot water storage tank 4 through the first pipe 1, the check valve 2 a and the pressure reducing valve 3, and hot water flows out from the top of the hot water storage tank 4. It flows into the hot water inlet of the hot water mixing valve 6 through the 1 pipe 1 and the check valve 2b. The tap water flows into the cold water inlet of the hot water mixing valve 6 through the second pipe 8 and the check valve 2c. Hot water and cold water are mixed in the hot water / mixing valve 6, hot water having an appropriate temperature flows out of the hot / water mixing valve 6, and water is discharged from the water discharge device 200 through the first pipe 1.
When the pressure in the hot water storage tank 4 exceeds the appropriate value, the relief valve 5 opens and discharges high-pressure steam or hot water through the drainage hose 1 'to the outside of the water heater A, so that the pressure in the hot water storage tank 4 reaches the appropriate value. Reduce.
The check valve 2a prevents the back flow of hot water from the water heater A to the upstream water pipe, and the check valves 2b, 2c, and 2d are upstream of the hot water storage tank 4 and the hot water storage tank 4 from the water discharger 200 side. Back flow of hot water to the first pipe 1 on the side is prevented.
When the negative pressure is generated in the hot water storage tank 4, the edge cut valve 10 opens the first pipe 1 downstream from the edge cut valve 10 to the atmosphere, and even if the check valves 2b, 2c, and 2d are broken, The internal hot water is prevented from flowing back to the hot water storage tank 4.
When the water heater A is not used for a long period of time, the drain valve 7 is opened, and the water in the hot water storage tank 4 is drained from the drain port of the drain valve 7 with the drain hose 1 'and the relief valve 5 having a negative pressure operating function. While replacing the air flowing into the hot water storage tank 4 through the first pipe 1, the hot water storage tank 4, the first pipe 1 extending between the hot water storage tank 4 and the check valve 2b, the first pipe 1 from It drains from the 2nd piping 8 extended between the branch point and the non-return valve 2c, and the 1st piping 1 extended between the branch point of the 2nd piping 8, and the hot water storage tank 4. FIG.

As shown in FIG. 2, the pressure reducing valve 3 includes a pressure reducing valve cassette 310 and a pressure reducing valve body 330.
The pressure reducing valve cassette 310 includes a cylinder 311, a piston head 312 slidably fitted to the cylinder 311, and a first piston rod 313 that extends from one end surface of the piston head 312 and protrudes from one end of the cylinder 311 to the outside of the cylinder 311. A cylindrical valve seat 314 extending from the inner peripheral edge of the one end of the cylinder 311, and a first valve body 315 fixed to one end of the first piston rod 313 protruding outside the cylinder 311 and facing the valve seat 314. , A pair of valve inlets 316 formed at the bottom of a circumferential groove 311a formed on the outer surface of the portion facing the first piston rod 313 on the circumferential wall of the cylinder 311 and the other end surface of the piston head 312 are screwed to the cylinder A second piston rod 317 protruding from the other end of 311 to the outside of the cylinder 311 and a second piston rod 317 A diaphragm 318 having a central portion fixed to one end protruding from the other end of the solder 311, a diaphragm case 320 facing the diaphragm 318 and forming a pressure sensitive chamber 319 in cooperation with the diaphragm 318, the cylinder 311, and the piston head 312; A pair of pressure introducing holes 321 that are formed in the peripheral wall of the cylinder 311 and extend from the one end to the other end of the cylinder 311 to guide the secondary pressure of the pressure reducing valve 3 to the pressure sensing chamber 319, and the diaphragm 318 are connected to the pressure sensing chamber 319. A first spring 322 that presses to the side, a spring case 323 that accommodates the first spring 322 and cooperates with the diaphragm case 320 to sandwich the periphery of the diaphragm 318, and a piston head that is accommodated in the circumferential groove of the piston head 312. An O-ring 324 that seals a sliding contact portion between 312 and the inner peripheral surface of the cylinder 311; And a O-ring 325, 326 housed in a circumferential groove formed on the outer circumferential surface of 1.
The pressure receiving area of the piston head 312 is set to a value larger than the pressure receiving area of the first valve body 315.

The cylinder 311 and the diaphragm case 320 are integrally formed of resin.
Diaphragm case 320 and press-processed metal plate spring case 323 are coupled by screws and caulking.
The pair of pressure introducing holes 321 have an oval cross section and are disposed so as to face each other with the cylinder center axis X interposed therebetween. The pair of valve inlets 316 is formed by leaving the peripheral portion of the cylinder 311 forming the bottom wall of the circumferential groove 311a notched over a predetermined circumferential length, leaving the vicinity of the pressure guiding hole 321 in a columnar shape with a sector shape. They face each other with the cylinder center axis X in between.
An annular groove 311b is formed in the piston head sliding region of the peripheral wall of the cylinder 311 from the other end side end surface of the cylinder 311 to the central portion in the longitudinal direction, and the peripheral wall of the cylinder 311 in the piston head sliding region is connected to the inner tube 311c. A double pipe composed of the pipe 311d is formed. The annular groove 311 b communicates with the pressure guiding hole 321 and forms a part of the pressure guiding hole 321.

The pressure reducing valve body 330 is made of resin. The pressure reducing valve body 330 communicates with a cylindrical portion 331 into which the cylinder 311 of the pressure reducing valve cassette 310 is inserted and fixed, a primary side opening 332 formed in the cylindrical portion 331 facing the valve inlet 316, and a primary side opening 332. An inlet cylinder 333, a secondary opening 334 formed in the cylinder 331 opposite the first valve body 315, and an outlet cylinder 335 communicating with the secondary opening 334. The inner peripheral surface of the cylindrical portion 331 forms an annular passage 336 outside the valve inlet 316 in cooperation with a peripheral groove 311 a formed on the outer peripheral surface of the cylinder 311.

The cylinder 311 of the pressure reducing valve cassette 310 is inserted into the cylindrical portion 331 of the pressure reducing valve body 330 and is prevented from coming off by the pin 340, and the contact portion between the cylinder 311 and the cylindrical portion 331 is sealed by the O-rings 325 and 326. And the pressure reducing valve body 330 are integrally assembled to constitute the pressure reducing valve 3.
A passage from the inlet cylinder 333 through the primary side opening 332, the annular passage 336, the valve inlet 316, the internal space of the cylinder 311 to the end of the valve seat 314 forms the primary passage of the pressure reducing valve 3, and the cylinder A passage from a portion of the valve body 315 accommodating the valve body 315 to the outlet tube portion 333 through the secondary side opening 334 forms a secondary side passage of the pressure reducing valve 3. The pressure introducing hole 321 allows the pressure sensitive chamber 319 to communicate with the secondary side passage.
An annular gap formed between the valve seat 314 and the valve body 315 forms a first series passage S between the primary side passage and the secondary side passage.
A piston having a cylinder 311, a piston head 312, a first piston rod 313 and a second piston rod 317, slidably inserted in the cylinder 311, and a first valve body 315 fixed to one end of the piston; The diaphragm 318, which is fixed to the other end of the piston and receives the secondary pressure, and the first spring 322 that urges the diaphragm 318 in the valve opening direction of the first valve body 315 are used to A first valve mechanism for variably adjusting the flow path area is formed.

The pressure reducing valve 3 extends through the piston head 312 and the second piston rod 317, and a second communication portion between the primary side passage and the secondary side passage that communicates the internal space of the cylinder 311 to the pressure sensing chamber 319. S 'and the second communicating portion S' are disposed in the large diameter portion, and abut on or away from the valve seat formed at the upstream end of the large diameter portion to open and close the second communicating portion S '. A second valve body 327 and a second spring 328 disposed in the large-diameter portion and abutting against the second piston rod 317 and the second valve body 327 to urge the second valve body 327 in the valve closing direction; The 2nd valve mechanism which has these is provided. By adjusting the screwing depth of the second piston rod 317, the urging force of the second spring 328 is adjusted, and the valve opening pressure of the second valve body 327 and consequently the valve opening pressure of the second valve mechanism are adjusted. Can do.

The inlet cylinder 333 of the pressure reducing valve 3 is connected to the check valve 2a of the water heater A via the first pipe 1, and the outlet cylinder 335 of the pressure reducing valve 3 is connected to the hot water storage tank of the water heater A via the first pipe 1. 4 is connected.

When the water discharge device 200 of the water heater A is closed and the water and hot water in the first pipe 1 are stopped, the first valve mechanism of the pressure reducing valve 3 is closed, and the water pressure in the primary passage is closed. As long as the primary pressure of the pressure reducing valve 3 is within an appropriate range, the second valve mechanism is also closed.
When the water discharge device 200 of the water heater A is opened, the secondary pressure of the pressure reducing valve 3 that is the water pressure in the secondary side passage of the pressure reducing valve 3 is reduced. As a result, the urging force in the valve closing direction due to the secondary pressure applied to the diaphragm 318 is reduced, and the diaphragm receiving the urging force of the first spring 322 is displaced toward the valve seat 314 and fixed to the diaphragm 318. The second piston rod 317 thus moved moves in a direction in which the piston head 312 and the first piston rod 313 follow the diaphragm 38 and approach the valve seat 314, the valve body 315 moves away from the valve seat 314, and the pressure reducing valve 3 Will open. When tap water flows from the primary passage to the secondary passage through the first passage S, a pressure loss occurs and the tap water is depressurized.
Since the secondary side passage and the pressure sensing chamber 319 communicate with each other, the secondary pressure of the pressure reducing valve 3 that is the tap water pressure in the secondary side passage is applied to the diaphragm 318. Since the O-ring 324 accommodated in the circumferential groove of the piston head 312 seals the sliding contact portion between the piston head 312 and the cylinder 3111 and the primary valve is within an appropriate range, the second valve mechanism is closed. The primary pressure of the pressure reducing valve 3 that is the tap water pressure in the side passage is not transmitted to the pressure sensing chamber 319 and is not applied to the diaphragm 318.
When the secondary pressure rises for some reason, the diaphragm 318 is displaced in a direction away from the valve seat 314 against the biasing force of the first spring 322, and the second piston rod 317 fixed to the diaphragm 318 is eventually moved to the piston head 312. The first piston rod 313 follows the diaphragm 318 and moves to the diaphragm 318 side, and the first valve body 315 approaches the valve seat 314. As a result, the first communication part S is narrowed, and the pressure loss when the tap water passes through the first communication part S increases. As a result, the secondary pressure decreases. Accordingly, in the pressure reducing valve 3, the secondary pressure is maintained below a predetermined value.

When the water discharge device 200 of the water heater A is closed and the flow of water and hot water in the first pipe 1 is stopped and eventually the flow of tap water in the pressure reducing valve 3 is stopped, the secondary pressure applied to the diaphragm 318 is increased. The pressure rises to the primary pressure, the diaphragm 318 is displaced away from the valve seat 314, and the valve body 315 comes into contact with the valve seat 314 to close the first communication portion S. As a result, the pressure reducing valve 3 is closed.

When the pressure reducing valve 3 is closed, if the primary pressure rises due to water hammer or freezing of the water pipe upstream of the water heater A, it is applied to the piston head 312 and the first valve body 315. Since the sum of the urging forces due to the primary pressure works in the valve closing direction, the first valve body 315 does not open the first passage S, but the second valve body 327 of the second valve mechanism has an urging force in the valve opening direction. Working, pressure resistance performance of the primary passage made of resin, water stop performance of the O-rings 325 and 326, performance of adjusting the first passage portion opening degree of the first valve body 315 (excessive compression from the valve seat 314 to the first valve body 315) When the force is applied, the first valve body 315 is plastically deformed, and the performance of adjusting the opening degree of the first series passage S may be reduced). When the primary pressure reaches an appropriate upper limit, the biasing force in the valve opening direction due to the primary pressure acting on the second valve body 327 is increased. 2 overcomes the bias of the valve closing direction of the spring 328, the second valve mechanism opens the second communicating portion S '. The primary passage communicates with the pressure sensing chamber 319, and the primary passage communicates with the secondary passage, and the primary pressure is diluted by the secondary pressure and reduced. As a result, the performance of the pressure reducing valve 3 is maintained satisfactorily.
After the second valve mechanism is opened and the primary side passage and the secondary side passage communicate with each other, when the secondary pressure rises beyond the appropriate range due to the application of the primary pressure, the relief valve 5 of the water heater A opens. Then, the secondary pressure is released to the external environment. As a result, after the second valve mechanism opens the second communication portion, occurrence of a situation in which the primary pressure rises above the upper limit appropriate for maintaining the performance of the pressure reducing valve 3 is prevented.
In the pressure reducing valve 3, when the primary pressure rises to a predetermined value when the valve is closed, the primary pressure is reduced without draining directly from the pressure reducing valve 3 to the outside of the pressure reducing valve 3, so that the pressure reducing valve 3 is connected to the relief valve 5 of the water heater A. In addition to the drain hose 1 ', there is no need to newly provide a drain hose.

In the pressure reducing valve 3, a second valve mechanism that opens and closes the second communication portion S ′ between the primary side passage and the secondary side passage is accommodated in the piston of the first valve mechanism, whereby the second valve mechanism is It is not necessary to dispose the pressure reducing valve outside the body, and an increase in size of the pressure reducing valve due to the provision of the second valve mechanism is suppressed.
A portion of the piston of the first valve mechanism near the diaphragm 318 forms a large-diameter piston head 312 that slides on the cylinder 311, and a portion of the piston of the first valve mechanism near the first valve body 315 has a small-diameter piston rod 313. Form. Therefore, from the viewpoint of workability, it is desirable that the second valve mechanism is housed in a portion near the diaphragm 318 of the piston of the first valve mechanism that forms the large-diameter piston head 312. In this case, the second communication portion S ′ is a communication portion between the primary side passage and the pressure sensitive chamber 319.

In the above embodiment, the pressure reducing valve body 330 is made of resin, but the material of the pressure reducing valve body 330 is not particularly limited.
The second valve mechanism may be accommodated in the piston rod 313.

The present invention is widely applicable to pressure reducing valves.

A Water heater having a can body 1 First piping 3 Pressure reducing valve 4 Hot water storage tank 5 Relief valve 310 Pressure reducing valve cassette 330 Pressure reducing valve body 315 First valve body 327 Second valve body 318 Diaphragm S First communication part S ′ Second Communication part

Claims (2)

The primary side passage, the secondary side passage, the piston that is slidably inserted into the cylinder, the first valve body fixed to one end of the piston, and the other end of the piston are received to receive the secondary pressure. A first spring that biases the diaphragm and the diaphragm in the valve opening direction of the first valve body, and variably adjusts the flow area of the first series passage portion between the primary side passage and the secondary side passage. And a second valve between the primary side passage and the secondary side passage having a second valve body and a second spring for biasing the second valve body in the valve closing direction. A second valve mechanism that opens and closes the communicating portion; the second valve mechanism is housed in a piston of the first valve mechanism; and the first valve mechanism is a first valve between the primary side passage and the secondary side passage. When the communication portion is closed, the second valve mechanism opens the second communication portion between the primary side passage and the secondary side passage with a predetermined primary pressure. That a pressure reducing valve. The diaphragm forms a part of the surrounding wall of the pressure sensing chamber communicating with the secondary side passage, and the second communication portion is a communication portion between the primary side passage and the pressure sensing chamber. 2. The pressure reducing valve according to 1.

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