JPH074974U - Pilot control valve - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a pilot-type control valve that does not generate the water hammer phenomenon by itself and is not affected by the water hammer generated by other valves. [Structure] The pilot control valve 1 has an inlet port 21
And a main body 2 having an outlet port 22 and a valve port 23 formed between the ports, and a diaphragm type main valve body 3 arranged in the main body so that the valve port can be selectively opened and closed. A main valve body having a passage and a bleed hole,
A pilot valve body 6 that selectively opens and closes the pilot passage 34, and an actuating device 4 that operates the pilot valve body, and the bleed hole 36 is defined between the main valve body and the main body. The pressure chamber is communicated with the inlet port side, and the pressure in the side pilot pressure chamber is changed by opening / closing the pilot passage to open / close the main valve body. The pilot control valve is provided with a flexible film body 7 on one surface of which the fluid pressure on the inlet port side acts and the other surface of which faces the auxiliary chamber, and the auxiliary chamber c is the pilot pressure chamber C. I understand.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a pilot type control valve, and more particularly to a pilot type control valve having a built-in water hammer prevention mechanism.

[0002]

[Prior art]

 As a pilot type solenoid valve using a diaphragm type main valve body, various structures have been developed as shown in, for example, Japanese Utility Model Publication No. 4-32272. When such a pilot type solenoid valve, that is, a control valve is used in the liquid circuit to control the opening and closing of the liquid flow, if the main valve element suddenly operates and closes, a water hammer occurs in the liquid circuit. There is a risk of damaging equipment connected to the liquid circuit. In order to reduce the water hammer generated by the operation of the pilot control valve, the bleed hole formed in the diaphragm type main valve body is made smaller so that the main valve body operates slowly. It is more susceptible to the water hammer generated by.

That is, the main valve body of the control valve may momentarily open when the hydraulic pressure in the liquid circuit rises sharply. For example, when the pilot solenoid valve described in the above publication is used in hot water supply equipment with a lever type water tap, if the lever of the water tap is moved abruptly and closed abruptly, a water hammer will be generated in the hot water supply circuit. However, the water hammer causes the diaphragm-type main valve element to be pushed up momentarily and open.

Therefore, conventionally, a water hammer preventing or absorbing device for absorbing the water hammer in the liquid circuit has been separately attached to the liquid circuit for use. However, it is costly to install a separate water hammer prevention device, and there is a space problem in a limited space such as hot water supply equipment.

[0005]

Problem to be Solved by the Invention The problem to be solved by the present invention is to provide a pilot type control valve which itself reduces the water hammer phenomenon and is not affected by the water hammer generated by other valves.

[0006]

[Means for Solving the Problems]

 The present invention is a main body in which an inlet and an outlet port and a valve opening between the ports are formed, and a diaphragm type main valve body in which the valve opening is selectively openable and closable. A main valve body having a pilot passage and a bleed hole formed therein; a pilot valve body for selectively opening and closing the pilot passage; and an operating device for operating the pilot valve body, wherein the bleed hole serves as the main valve body. A pilot type that communicates a limited pilot pressure chamber with the main body and the inlet port side, and changes the pressure in the side pilot pressure chamber by opening and closing the pilot passage to open and close the main valve body In the control valve, one surface is provided with a flexible film body on which the fluid pressure on the inlet port side acts and the other surface faces the auxiliary chamber, and the auxiliary chamber communicates with the pilot pressure chamber. Is configured.

In the above pilot type control valve with a water hammer prevention mechanism, the membrane may be fixed to a side portion of a valve chamber communicating with the inlet port, or a valve chamber may be formed in the main body to form a valve chamber. An auxiliary valve port may be formed between the valve chamber and the inlet port, and the membrane body may be arranged so as to face the auxiliary valve port. Further, the membrane body may be arranged on the outer circumference of the diaphragm type main valve body, and the auxiliary chamber may be formed on the outer circumference of the pilot pressure chamber.

[0008]

[Action]

 In the pilot-type control valve with a water hammer prevention mechanism having the above structure, when the pilot passage is open, the fluid that has entered the pilot pressure chamber from the bleed hole flows out to the outlet via the pilot passage. For this reason, the pressure in the pilot pressure chamber cannot be increased, and the main valve body keeps its valve opening. When the actuator is operated and the pilot passage is closed by the pilot valve body, the pilot pressure chamber rises due to the fluid entering from the bleed hole, and the main valve body closes the valve port. When a water hammer occurs in the circuit connected to the inlet side, the membrane plate is pushed to the auxiliary chamber side, the pressure in the auxiliary chamber rises, and the increased pressure is passed into the pilot pressure chamber. For this reason, the pressure in the pilot pressure chamber also rises, preventing the main valve body from rising and opening the valve opening.

[0009]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a pilot type control valve (hereinafter simply referred to as a control valve) 1 of the first embodiment. This control valve includes a main body 2 having an inlet port 21, an outlet port 22, a valve opening 23 between the inlet port and the outlet port, and a valve seat 24 around the opening end of the valve opening, and a valve opening in the main body 2. A diaphragm-type main valve body 3 that is arranged to be able to open and close 23 and a solenoid 4 that constitutes an actuator for the pilot valve body are provided.

In this embodiment, the main body includes a portion 20 in which the inlet port 21, outlet port 22, valve opening 23 and valve seat 24 are formed, and a portion 20 a attached to a side portion of the portion 20. It is configured. The body portion 20a is fixed to the portion 20 by a known means such as a set screw. The portion 20 of the main body 2 is formed with a concave portion 25 that opens to the upper surface and holes 26 and 27 that open to the side. The recess 25 communicates with the inlet port 21 and the valve port 23 at the bottom. The portion 20a is formed with a recess 26a that communicates with the hole 26 and a through hole 27a that communicates the hole 27 of the portion 20 with the recess 26a.

The diaphragm-type main valve body 3 is contained in the recess 25 of the portion 20 of the main body 2, and is provided with a flexible diaphragm 31 such as rubber and a support body 32 attached to the diaphragm 31. ing. The diaphragm 31 is fixed to the main body by the solenoid 4 via a spacer 51 placed in the recess 25, and the central portion of the diaphragm 31 can be engaged with the valve seat 24 formed in the portion 20. A boss portion 33 that penetrates the diaphragm 31 and extends vertically is formed in the center of the support body, and a pilot passage 34 that penetrates vertically is formed in the boss portion 33. The support 32 is further formed with a protrusion penetrating the diaphragm 31 in the peripheral portion thereof, and a bleed hole 36 is formed on the protrusion to connect the inlet port 21 and the pilot pressure chamber C defined by the recess 25. Has been done.

The solenoid 4 includes a spacer 51, a coil bobbin 41 arranged on an outer periphery of a cylindrical portion 52, a coil winding 42 wound around the coil bobbin 41, yokes 43 and 44 made of a magnetic material surrounding the coil winding, and a cylindrical portion 52. A movable iron core 45 is movably arranged therein, and a spring 46 that presses the movable iron core 45 toward the main valve body 3. A pilot valve body 6 is attached to the lower surface of the movable iron core 45 to selectively contact the upper surface of the boss portion 33 of the support body 32 to close the pilot passage 34. The yoke 44 fixes the solenoid 4 to the main body 2 and acts as a cover for covering the pilot pressure chamber C defined by the recess 25.

A membrane 7 such as a flexible diaphragm made of rubber or the like is arranged between the two portions 20 and 20 a of the main body 2. The membrane body 7 has its periphery fixed by the portions 20 and 20a, and separates the hole 26 formed in the portion 20 and the auxiliary chamber c defined by the recess 26a formed in the portion 20a. The pilot pressure chamber C and the hole 27a are communicated with each other by the hole 27. Therefore, the pilot pressure chamber C and the auxiliary chamber c are communicated with each other through the through hole 27a, the hole 27 and the hole formed in the annular portion 55 of the spacer 51. A spring 8 is provided in the recess 26a between the film body 7 and the portion 20a.

In the control valve having the above-described structure, when the coil winding 42 of the solenoid 4 is not energized, the movable iron core 45 is pushed downward by the spring 46 and abuts the upper surface of the boss portion 33 of the support body 32 so as to contact the pilot passage. 34 is closed. Therefore, the fluid in the pilot pressure chamber C cannot flow to the outlet port 22 side through the pilot passage 34, and the pressure in the pilot pressure chamber rises due to the fluid flowing from the inlet port 21 through the bleed hole 36. ing. Therefore, the main valve body 3 is pushed downward by the pressure, and the lower surface of the diaphragm 31 forming a part of the main valve body 3 is in contact with the valve seat 24. Therefore, the valve port 23 is closed and the control valve is closed. When the coil winding 42 is energized and the movable iron core 45 is pulled up, the pilot passage 34 opens and the fluid in the pilot pressure chamber C flows out to the outlet port 22 through the pilot passage. Since the flow rate flowing out through the pilot passage is larger than the flow rate flowing into the pilot pressure chamber through the bleed hole 36, the pressure in the pilot pressure chamber drops and the main valve body 3 acts on the lower side. Pushed up by the pressure on the inlet side, the main valve element separates from the valve seat 24 and opens the valve opening. Therefore, the control valve is opened.

When water hammer occurs on the inlet side due to a sudden operation of a valve (not shown) connected to the inlet port 21, the pressure on the inlet side rises momentarily, but when the pressure rises, the membrane body 7 is pushed toward the auxiliary chamber c, and the pressure in the auxiliary chamber c rises. The increase in the pressure in the auxiliary chamber c is transmitted to the pilot pressure chamber C through the through holes 27a, the holes 27 and the holes of the spacers, and the pressure in the pilot pressure chamber also increases. Therefore, even if the pressure on the inlet side rises, the main valve body 3 will not rise carelessly and separate from the valve seat 24.

In FIG. 2, a control valve 1'of the second embodiment is shown. This control valve is different from the control valve of the previous embodiment in the structure of the main body and the arrangement of the film body, but is otherwise the same. Therefore, parts having the same structures as those in the previous embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. In this control valve, the main body 2'is composed of a portion 20 ', a portion 20a' attached to the inlet side of the portion 20 ', and a portion 20b' attached above the portion 20a '. . The portion 20a 'is formed with a hole 26a' communicating with the inlet 21 formed in the portion 20 '. Portion 20a 'is further formed with a tubular portion 28a' projecting into hole 26a 'of portion 20a', which tubular portion 28a 'defines an auxiliary valve port 23a'. The auxiliary valve port 23a 'communicates with the inlet port 21a'. The membrane body 7 is arranged opposite to the open end of the auxiliary valve port 23a 'defined by the tubular portion 28a' and is adapted to engage with the tip of the tubular portion. The film body may not contact the tip of the tubular portion, or the tubular portion may be removed. The auxiliary chamber c'defined by the recess 26b 'communicates with the pilot pressure chamber C through the through hole 27b formed in the portion 20b' and the hole 27 formed in the portion 20. A spring 8 is provided in the recess 26b '.

The opening / closing operation of the control valve 1 ′ of the above embodiment is the same as the opening / closing operation of the control valve 1 of the previous embodiment. However, the fluid that has entered from the inlet port 21a 'is different from the above-mentioned embodiment in that it pushes the membrane body 7 to enter the hole 26a' and then enters the inlet port 21. Further, when a water hammer occurs on the inlet port side, the film body 7 is pushed to the auxiliary chamber c side by the pressure increase by the water hammer, and the pressure in the auxiliary chamber is increased.

In FIG. 3, a control valve 1 ″ of a third embodiment of the present invention is shown. In the control valve of this embodiment, the body 2 ″ differs from the previous embodiment in one portion 20 ″. It is different from the above two embodiments in that the film body is formed on the outer circumference of the diaphragm of the diaphragm type main valve body integrally with the diaphragm, and the auxiliary chamber is formed on the outer circumference of the pilot pressure chamber C. Only different parts will be described and common parts will be denoted by the same reference numerals and description thereof will be omitted.

A ring-shaped film body 7 ″ surrounding the diaphragm is integrally formed on the outer periphery of the diaphragm 31 ″ of the main valve body 3 ″ of the control valve 1 ″, and a ring-shaped fitting groove 71 ″ is formed at the connecting portion. Is formed over the entire circumference. Also, two concentric annular portions 55 "and 56" that are radially separated are integrally formed on the spacer 51 ", and the two annular portions 55" are formed. The auxiliary chamber c "is defined by the membrane 7" between "and 56". At the lower end edge (in FIG. 3) of the annular portion 55, a fitting convex portion 57 ″ fitted in the fitting groove 71 ″ is formed over the entire circumference. The auxiliary chamber c ″ and the pilot pressure chamber C ″ limited to the inside of the annular portion 55 ″ are communicated with each other by a through hole 58 ″ formed in the insert 51 ″.

The opening / closing operation of the control valve 1 ″ according to the third embodiment is the same as the opening / closing operation of the control valve according to the above-described two embodiments. Further, the opening / closing operation of the film body 7 ″ in the case where water hammer occurs on the inlet side. The operation and function are the same as in the above embodiment. Therefore, detailed description of the operation is omitted.

In the third embodiment described above, the auxiliary chamber is formed in an annular shape around the pilot pressure chamber, but the auxiliary chamber does not necessarily have to be formed in an annular shape and may be formed discretely in the circumferential direction. Further, the film body does not have to be formed integrally with the diaphragm of the main valve body, but may be formed as a separate body and fixed in the main body.

[0022]

[Effect of device]

 According to the present invention, the following effects can be achieved. (B) Since the membrane body operates due to the pressure fluctuation on the inlet side and the pressure in the pilot pressure chamber can be changed in response to the pressure fluctuation, a valve attached to the liquid circuit connected to the inlet side can be used. Even if a water hammer occurs due to the action of, the inadvertent opening of the main valve body can be prevented. (B) Since the volume of the pilot pressure chamber is substantially increased, the main valve body can be opened and closed slowly, and the water hammer can be reduced by the valve closing operation of itself.

[Brief description of drawings]

FIG. 1 is a sectional view of a pilot type control valve according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a pilot type control valve according to a second embodiment of the present invention.

FIG. 3 is a sectional view of a pilot type control valve according to a third embodiment of the present invention.

[Explanation of symbols]

1, 1 ', 1 "Control valve 2, 2', 2"
Main body 3 Main valve body 4 Solenoid 6 Pilot valve body 7, 7 "Membrane body 21 Inlet port 22 Outlet port 23 Valve mouth 31 Diaphragm 34 Pilot passage 36 Bleed passage C Pilot pressure chamber c, c" Auxiliary chamber

Claims (4)

[Scope of utility model registration request] 1. A main body in which an inlet and an outlet port and a valve opening between the ports are formed, and a diaphragm type main valve body which is arranged in the main body so that the valve opening can be selectively opened and closed. A main valve body having a pilot passage and a bleed hole formed therein, a pilot valve body that selectively opens and closes the pilot passage, and an actuating device that operates the pilot valve body. A pilot type in which a limited pilot pressure chamber is communicated with the main body and the inlet port side, and the pressure in the side pilot pressure chamber is changed by opening and closing the pilot passage to open and close the main valve body. In the control valve, one surface is provided with a flexible film body on which the fluid pressure on the inlet port side acts and the other surface faces the auxiliary chamber,
A pilot type control valve with a water hammer prevention mechanism, wherein the auxiliary chamber communicates with the pilot pressure chamber. 2. The pilot type control valve with a water hammer prevention mechanism according to claim 1, wherein the film body is fixed to a side portion of a valve chamber communicating with the inlet port. valve. 3. The pilot control valve with a water hammer prevention mechanism according to claim 1, wherein a valve chamber is formed in the main body, and an auxiliary valve port is formed between the valve chamber and the inlet port. A pilot type control valve with a water hammer prevention mechanism, wherein the film body is arranged facing the auxiliary valve port. 4. The pilot type control valve with a water hammer prevention mechanism according to claim 1, wherein the film body is arranged on an outer periphery of the diaphragm type main valve body and the auxiliary chamber is formed on an outer periphery of the pilot pressure chamber. This is a pilot type control valve with a water hammer prevention mechanism.