CN213899906U

CN213899906U - Pressure regulating valve

Info

Publication number: CN213899906U
Application number: CN202022986734.5U
Authority: CN
Inventors: 李永达; 石良; 丁焕钦
Original assignee: Zhejiang Liyongda Refrigeration Machinery Co ltd
Current assignee: Zhejiang Liyongda Refrigeration Machinery Co ltd
Priority date: 2020-12-11
Filing date: 2020-12-11
Publication date: 2021-08-06
Anticipated expiration: 2030-12-11

Abstract

The utility model provides a pressure regulating valve relates to pump valve technical field among the refrigerating system, has solved the technical problem that spring life is than short among the pressure regulating valve who exists among the prior art. The device comprises a valve body, a valve core, a piston, an adjusting device and a communicating piece, wherein a partition plate is arranged in the valve body, the partition plate divides the interior of the valve body into an inlet cavity and an outlet cavity, and a through hole is formed in the partition plate; the piston can move on the inner wall of the outlet cavity and can push the valve core and separate the valve core from the through hole; a diaphragm is arranged between the adjusting device and the communicating piece, a communicating cavity is arranged in the communicating piece, and the diaphragm can block the communicating cavity; when the pressure regulating valve is in a valve opening state, the pressure of the medium in the inlet cavity to the diaphragm is larger than the pressure of the regulating device to the diaphragm, the medium in the communicating cavity can enter the outlet cavity and can push the piston to move so as to separate the valve core from the through hole, and the medium in the inlet cavity flows into the outlet cavity through a gap between the valve core and the through hole.

Description

Pressure regulating valve

Technical Field

The utility model belongs to the technical field of pump valve technique among the refrigerating system and specifically relates to a pressure regulating valve is related to.

Background

The pressure regulating valve is also called self-operated balance valve, flow control valve, flow controller, dynamic balance valve and flow balance valve, and is a visual, simple and convenient flow regulating and controlling device. The flow can be directly set according to the design by applying the pressure regulating valve in the pipe network, the valve can automatically eliminate the residual pressure head of the pipeline and the flow deviation caused by pressure fluctuation under the action of water, the set flow is kept unchanged no matter how the system pressure changes, the functions of the valve enable the pipe network flow regulation to be completed at one time, the net regulation work is changed into simple flow distribution, and the hydraulic imbalance of the pipe network is effectively solved.

In the prior art, a spring arranged in a regulating device is used for counteracting the acting force of high-pressure liquid on a valve core in the regulating process of the pressure regulating valve and pushing the valve core to block a water inlet passage. The spring is in under stronger operating condition, and the required intensity of spring is higher among the pressure regulating valve, and the spring receives bigger effort simultaneously, leads to the life of spring to shorten, and then has influenced pressure regulating valve's use quality.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a pressure regulating valve to solve the technical problem that spring life ratio is short among the pressure regulating valve that exists among the prior art. The utility model provides a plurality of technical effects that preferred technical scheme among a great deal of technical scheme can produce see the explanation below in detail.

In order to achieve the above purpose, the utility model provides a following technical scheme:

the utility model provides a pressure regulating valve, including valve body, case, piston, adjusting device and intercommunication piece, wherein, be provided with the division board in the valve body, the division board divide into inlet chamber and export chamber the valve body inside, be provided with the through-hole on the division board, inlet chamber and export chamber are linked together through the through-hole;

the valve core is connected with one end of the piston, the other end of the piston is in sealing contact with the inner wall of the outlet cavity, the piston can move on the inner wall of the outlet cavity, the valve core can block the through hole, and the piston can push the valve core and separate the valve core from the through hole;

the valve body is connected with the communicating piece in a sealing mode, the adjusting device is connected with the communicating piece in a sealing mode, a membrane is arranged between the adjusting device and the communicating piece, a communicating cavity is formed in the communicating piece, one end of the communicating cavity is communicated with the outlet cavity, the other end of the communicating cavity is communicated with the inlet cavity through a conduit, and the communicating cavity can be blocked by the membrane;

the pressure regulating valve has an open valve state and a closed valve state, when the pressure regulating valve is in the open valve state, the pressure of a medium in the inlet cavity to the diaphragm is greater than the pressure of the regulating device to the diaphragm, part of the medium in the inlet cavity enters the communicating cavity through the guide pipe and can push the diaphragm to conduct the communicating cavity, the medium in the communicating cavity can enter the outlet cavity and can push the piston to move so as to separate the valve core from the through hole, and the medium in the inlet cavity flows into the outlet cavity through a gap between the valve core and the through hole.

Optionally, adjusting device includes upper valve cover, elastic component, pressure adjustment spare and upper valve cap, upper valve cover with intercommunication piece sealing connection, the elastic component is located in the upper valve cover just the one end butt of elastic component is in on the diaphragm, the other end of elastic component with pressure adjustment spare is connected just pressure adjustment spare can be adjusted the elastic component is used in elastic force on the diaphragm, the free end of pressure adjustment spare can stretch out upper valve cover, upper valve cover with upper valve cap threaded connection just upper valve cap can cover pressure adjustment spare's free end.

Optionally, the elastic element includes an adjusting spring, a lower spring seat, an upper spring seat, a steel ball and a slider, the upper end of the adjusting spring is connected to the upper spring seat, the lower end of the adjusting spring is connected to the lower spring seat, the steel ball is located between the slider and the lower spring seat, and the slider abuts against the diaphragm.

Optionally, the pressure adjusting part includes pressure adjusting rod, first bolt and first gasket, first bolt with first gasket is all inlayed in the upper valve lid, the pressure adjusting rod passes in proper order first bolt with first gasket and with the elastic component is connected, the pressure adjusting rod with first bolt threaded connection.

Optionally, still include the needle valve, the needle valve is located the side of connecting piece, the one end of needle valve can insert in the connecting piece just the needle valve with the intercommunication chamber is linked together, the needle valve can be connected with measuring device.

Optionally, the piston comprises a piston rod and a piston block, the piston rod is fixedly connected with the piston block, the free end of the piston rod is connected with the valve core, the piston block is in sealing contact with the inner wall of the outlet cavity, and the cross-sectional area of the piston block is larger than that of the piston rod;

the piston block is provided with a pressure relief hole.

Optionally, the valve further comprises a manual valve opening device, the manual valve opening device is connected with the valve body in a sealing mode, the manual valve opening device is connected with the valve core, and the valve core can be pulled to be separated from the through hole by the manual valve opening device.

Optionally, the manual valve opening device includes a lower valve cap, a manual valve rod, a stop collar, a second bolt, a second gasket, and a lower valve cap, the lower valve cap is connected to the valve body in a sealing manner, the stop collar is embedded in the valve core, the second bolt and the second gasket are embedded in the lower valve cap, the stop collar is sleeved on one end of the manual valve rod and limits the manual valve rod to be detached from the stop collar, a free end of the manual valve rod passes through the second gasket, the second bolt and the lower valve cap, and a free end of the manual valve rod extends out of the lower valve cap, the manual valve rod is connected to the second bolt in a threaded manner, and the lower valve cap is connected to the lower valve cap in a threaded manner and can cover the free end of the manual valve rod.

Optionally, the valve element includes a positioning column, a connecting piece and a limiting plate, one side of the connecting piece is fixedly connected to the positioning column, the other side of the connecting piece is fixedly connected to the limiting plate, the limiting plates are distributed along a circumferential direction of the connecting piece, the piston abuts against the connecting piece, and the limiting plate and the piston are located on the same side of the connecting piece;

and the positioning column is internally provided with a mounting hole.

Optionally, the valve further comprises a seat returning spring, the seat returning spring is located in the inlet cavity, the seat returning spring is sleeved on the valve core, and the elastic force of the seat returning spring enables the valve core to move until the valve core blocks the through hole.

The utility model provides a pair of pressure regulating valve, high pressure medium is through being used in on the piston, make the piston remove, and then promote the case and remove, make the case with the through-hole part mutually, pressure regulating valve just is in the open valve state, and adjusting device is to applying pressure to the diaphragm, also can change the size of applying pressure to the diaphragm simultaneously, in order to make the diaphragm can not stop up the intercommunication chamber, high pressure medium is greater than adjusting device to the diaphragm is to applying pressure to the diaphragm, and then make the diaphragm remove, make the intercommunication chamber switch on, adjusting spring among the adjusting device need not directly act on the case, intensity among the adjusting spring does not need too high, with the technical problem that spring life is than short among the pressure regulating valve who exists among the solution prior art.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a sectional view of a pressure regulating valve provided in an embodiment of the present invention;

fig. 2 is a front view of a pressure regulating valve provided in an embodiment of the present invention;

FIG. 1, valve body; 11. a partition plate; 12. an inlet chamber; 13. an outlet chamber; 14. a dust cover; 2. a valve core; 21. a positioning column; 211. mounting holes; 22. a connecting member; 23. a limiting plate; 3. a piston; 31. a piston rod; 32. a piston block; 321. a pressure relief vent; 4. an adjustment device; 41. an upper valve cover; 42. an elastic member; 421. adjusting the spring; 422. a lower spring seat; 423. an upper spring seat; 424. steel balls; 425. a slider; 43. a pressure regulating member; 431. a pressure regulating rod; 432. a first bolt; 433. a first gasket; 44. an upper bonnet; 5. a communicating member; 51. a communicating cavity; 6. a membrane; 7. a needle valve; 8. a manual valve opening device; 81. a lower valve cover; 82. a manual valve stem; 83. a limiting sleeve; 84. a second bolt; 85. a second gasket; 86. a lower bonnet; 9. a return spring; 10. a conduit; 20. a valve seat.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below. It is to be understood that the embodiments described are only some embodiments of the invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

In the description of the present invention, it is to be noted that "a plurality" means two or more unless otherwise specified; the terms "upper", "lower", "left", "right", "inner", "outer", "front", "rear", "head", "tail", and the like are used in an orientation or positional relationship indicated based on the orientation or positional relationship shown in the drawings for convenience of description and simplicity of description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is also to be understood that the terms "mounted", "connected" and "connected", unless expressly specified or limited otherwise, are intended to be interpreted broadly, as meaning either a fixed connection or a removable connection, or an integral connection; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present invention can be understood as the case may be, by those of ordinary skill in the art.

The utility model provides a pressure regulating valve, including valve body 1, case 2, piston 3, adjusting device 4 and communicating piece 5, wherein, be provided with division board 11 in the valve body 1, division board 11 is the bending structure, division board 11 divides the valve body 1 inside into intake chamber 12 and outlet chamber 13, be provided with the through-hole on the division board 11, intake chamber 12 and outlet chamber 13 are linked together through the through-hole, intake chamber 12 can be linked together with the feed liquor pipeline, outlet chamber 13 can be linked together with the liquid outlet pipeline, the port of intake chamber 12 and outlet chamber 13 both adopts flange to add the cover structure, and can be covered with shield 14;

the valve core 2 is connected with one end of the piston 3, the other end of the piston 3 is in sealing contact with the inner wall of the outlet cavity 13, the piston 3 can move on the inner wall of the outlet cavity 13, the piston 3 is positioned in the position far away from the port in the outlet cavity 13, and simultaneously, the outlet cavity 13 is divided into two parts by the piston 3 in the moving process, namely a containing cavity and a pressure cavity, the containing cavity is directly communicated with the liquid outlet pipeline, the medium in the inlet cavity 12 directly enters the containing cavity through the through hole, the medium in the pressure cavity is used for providing piston pressure, further pushing the piston, the medium in the pressure chamber flows in from the communicating chamber 51, the containing chamber is communicated with the pressure chamber through the pressure relief hole 321, the valve core 2 can block the through hole, the piston 3 can push the valve core 2 and separate the valve core 2 from the through hole, the medium in the inlet cavity 12 can be enabled to flow into the outlet cavity 13 from the position where the valve core 2 is separated from the through hole;

the upper end of the valve body 1 is hermetically connected with a communicating piece 5, the adjusting device 4 is hermetically connected with the communicating piece 5, a membrane 6 is arranged between the adjusting device 4 and the communicating piece 5, the membrane 6 is made of stainless steel, a communicating cavity 51 is arranged inside the communicating piece 5, one end of the communicating cavity 51 is communicated with an outlet cavity 13, the other end of the communicating cavity 51 is communicated with an inlet cavity 12 through a conduit 10, the conduit 10 is positioned in the valve body 1, the communicating cavity 51 can be blocked by the membrane 6, the communicating cavity 51 is divided into a central communicating cavity and a lateral communicating cavity, the central communicating cavity is communicated with the outlet cavity 13, the lateral communicating cavity is communicated with the inlet cavity 12 through the conduit 10, the central communicating cavity is communicated with the lateral communicating cavity, the central communicating cavity can be blocked by the membrane 6, the central communicating cavity is not communicated with the lateral communicating cavity, the central communicating cavity is also provided with the valve seat 20, the valve seat 20 is of a hollow structure, and the valve seat 20 can be blocked by the membrane 6, the communication chamber 51 can be blocked;

when the pressure regulating valve is in the valve opening state, the pressure of a medium in the inlet cavity 12 to the membrane 6 is greater than the pressure of the regulating device 4 to the membrane 6, so that the membrane 6 is far away from the end face of the valve seat 20, the communication cavity 51 is communicated, part of the medium in the inlet cavity 12 enters the communication cavity 51 through the conduit 10 and can push the membrane 6 to conduct the communication cavity 51, the medium in the communication cavity 51 can enter the outlet cavity 13 and can push the piston 3 to move so that the valve core 2 is separated from the through hole, and the medium in the inlet cavity 12 flows into the outlet cavity 13 through a gap between the valve core 2 and the through hole; when the pressure regulating valve is in a valve closing state, the pressure of the medium in the inlet cavity 12 to the membrane 6 is smaller than the pressure of the regulating device 4 to the membrane 6, so that the valve seat 20 is blocked by the membrane 6 again, the communicating cavity 51 is blocked, and then the medium in the inlet cavity 12 cannot enter the upper part of the outlet cavity 13 through the communicating cavity 51, so that the piston 3 cannot be pushed to move, and then the valve core 2 blocks the through hole, so that the medium in the inlet cavity 12 cannot flow into the outlet cavity 13 through a gap between the valve core 2 and the through hole. The utility model provides a pair of pressure regulating valve, high pressure medium is through being used in piston 3, make piston 3 remove, and then promote case 2 and remove, make case 2 with the through-hole part mutually, pressure regulating valve just is in the open valve state, and adjusting device 4 is to diaphragm 6 exerting pressure, also can change the size of exerting pressure to diaphragm 6 simultaneously, intercommunication chamber 51 can not be stopped up in order to make diaphragm 6, high pressure medium is greater than adjusting device 4 to diaphragm 6 exerting pressure, and then make diaphragm 6 remove, make intercommunication chamber 51 switch on, adjusting spring 421 in the adjusting device 4 need not directly act on case 2, intensity in adjusting spring 421 does not need too high, in order to solve the pressure regulating valve that exists among the prior art in the technical problem that spring life is than short.

As an alternative embodiment, the adjusting device 4 includes an upper bonnet 41, an elastic member 42, a pressure adjusting member 43 and an upper bonnet 44, the upper bonnet 41 is connected with the communicating member 5 in a sealing manner, the diaphragm 6 is located between the upper bonnet 41 and the communicating member 5, and a gasket is arranged at a position where both the upper bonnet 41 and the communicating member 5 are in contact with the diaphragm 6, in order to prevent the medium in the communicating member 5 from flowing into the upper bonnet 41 through the diaphragm 6, the elastic member 42 is located in the upper bonnet 41, and one end of the elastic member 42 abuts against the diaphragm 6, in order to apply an elastic force to the diaphragm 6, the other end of the elastic member 42 is connected with the pressure adjusting member 43, and the pressure adjusting member 43 can adjust the elastic force of the elastic member 42 acting on the diaphragm 6, the pressure adjusting member 43 can set the elastic force of the elastic member 42 acting on the diaphragm 6, and only when the pressure of the medium in the inlet cavity 12 on the diaphragm 6 is greater than the set elastic force, the pressure regulating valve is in an open state, the free end of the pressure regulating member 43 can extend out of the upper bonnet 41, so as to facilitate the adjustment of the elastic force, the upper bonnet 41 is in threaded connection with the upper bonnet 44, the upper bonnet 44 can cover the free end of the pressure regulating member 43, and the upper bonnet 44 is used for protecting the pressure regulating member 43.

As an optional implementation manner, the elastic member 42 includes an adjusting spring 421, a lower spring seat 422, an upper spring seat 423, a steel ball 424 and a sliding block 425, the upper end of the adjusting spring 421 is connected to the upper spring seat 423, the end of the pressure adjusting rod 431 is connected to the upper spring seat 423, the lower end of the adjusting spring 421 is connected to the lower spring seat 422, the steel ball 424 is located between the sliding block 425 and the lower spring seat 422, the sliding block 425 abuts against the diaphragm 6, the side wall of the sliding block 425 is matched with the inner wall of the upper valve cover 41, so that the sliding block 425 is prevented from shaking, and the sliding block 425 directly applies pressure to the diaphragm 6.

As an alternative embodiment, the pressure adjusting member 43 includes a pressure adjusting rod 431, a first bolt 432 and a first washer 433, the first bolt 432 and the first washer 433 are both embedded in the upper bonnet 41, the first washer 433 is provided with a packing layer, the pressure adjusting rod 431 sequentially passes through the first bolt 432 and the first washer 433 and is connected with the upper spring seat 423, the pressure adjusting rod 431 is in threaded connection with the first bolt 432, the pressure adjusting rod 431 is rotated to move the pressure adjusting rod 431 in a direction approaching or separating from the adjusting spring 421, so that the adjusting spring 421 can be compressed, the compression amount of the adjusting spring 421 can be adjusted according to the movement amount of the pressure adjusting rod 431, and further, the elastic force of the adjusting spring 421 can be adjusted.

As an optional implementation mode, the air conditioner further comprises a needle valve 7, the needle valve 7 is located on the side face of the communicating piece 5, one end of the needle valve 7 can be inserted into the communicating piece 5, the needle valve 7 is communicated with the side communicating cavity, the needle valve 7 can be connected with a measuring device, the measuring device can detect the change of pressure in the inlet cavity 12 through the needle valve 7, the needle valve 7 comprises a needle valve body, a valve core and a nut, one end of the needle valve body extends into the side communicating cavity, the needle valve body is matched and connected with the side communicating cavity, the valve core is located in the needle valve body, and the nut is sleeved at the other end of the needle valve body.

As an alternative embodiment, the piston 3 includes a piston rod 31 and a piston block 32, the piston rod 31 is fixedly connected with the piston block 32, the free end of the piston rod 31 is connected with the valve core 2, the piston block 32 is in sealing contact with the inner wall of the outlet cavity 13, the medium entering the outlet cavity 13 from the communicating cavity 51 is used for applying pressure to the piston block 32, and the cross-sectional area of the piston block 32 is larger than that of the piston rod 31, so as to better push the valve core 2;

the piston block 32 is provided with a pressure relief hole 321, and when the pressure regulating valve enters a closed state from an open state, part of the medium is left in the communication cavity 51 and the pressure cavity, and the part of the medium flows into the accommodating cavity from the pressure relief hole 321 and then can flow into the liquid outlet pipeline.

As an optional embodiment, the pressure regulating valve further comprises a manual valve opening device 8, the manual valve opening device 8 is connected with the valve body 1 in a sealing mode, the manual valve opening device 8 is connected with the valve core 2, and the manual valve opening device 8 can pull the valve core 2 to be separated from the through hole, so that a user can open the pressure regulating valve forcibly due to emergency.

As an alternative embodiment, the manual valve opening device 8 includes a lower bonnet 81, a manual valve rod 82, a limit sleeve 83, a second bolt 84, a second gasket 85 and a lower bonnet 86, the lower bonnet 81 is connected with the lower end of the valve body 1 in a sealing manner, the limit sleeve 83 is embedded in the valve core 2, the second bolt 84 and the second gasket 85 are embedded in the lower bonnet 81, a packing layer is arranged in the second gasket 85, the limit sleeve 83 is sleeved on one end of the manual valve rod 82 and the limit sleeve 83 limits the manual valve rod 82 to be separated from the limit sleeve 83, the free end of the manual valve rod 82 passes through the second gasket 85, the second bolt 84 and the lower bonnet 81 and extends out of the lower bonnet 81, the manual valve rod 82 is connected with the second bolt 84 in a threaded manner, the lower bonnet 86 is connected with the lower bonnet 81 in a threaded manner, the lower bonnet 86 can cover the free end of the manual valve rod 82, when the manual valve rod 82 is rotated, so that the manual valve rod 82 moves in a direction far away from the through hole, and then the valve core 2 is driven to move through the limiting sleeve 83, so that the valve core 2 is separated from the through hole, and the medium in the inlet cavity 12 flows to the outlet cavity 13.

As an optional embodiment, the valve core 2 includes a positioning column 21, a connecting piece 22 and limiting plates 23, one side of the connecting piece 22 is fixedly connected with the positioning column 21, the other side of the connecting piece 22 is fixedly connected with the limiting plates 23, the limiting plates 23 are distributed along the circumferential direction of the connecting piece 22, a gap exists between two adjacent limiting plates 23, so as to facilitate medium circulation, the piston 3 abuts against the connecting piece 22, and the limiting plates 23 and the piston 3 are located on the same side of the connecting piece 22;

the positioning column 21 is internally provided with an installation hole 211, the limiting sleeve 83 is embedded in the installation hole 211, one end of the manual valve rod 82 extends into the installation hole 211, the diameter of the end part of the manual valve rod 82 is larger than that of the limiting sleeve 83, and the end part of the manual valve rod 82 cannot be drawn out of the limiting sleeve 83 but can drive the limiting sleeve 83 to move.

As an optional embodiment, a seat returning spring 9 is further included, the seat returning spring 9 is located in the inlet chamber 12, the seat returning spring 9 is sleeved on the valve core 2, the other end of the seat returning spring 9 is connected to the lower valve cover 81, and when the pressure regulating valve enters the valve closing state from the valve opening state, the elastic force of the seat returning spring 9 can move the valve core 2 until the valve core 2 blocks the through hole.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A pressure regulating valve is characterized by comprising a valve body (1), a valve core (2), a piston (3), a regulating device (4) and a communicating piece (5), wherein,

a partition plate (11) is arranged in the valve body (1), the partition plate (11) divides the interior of the valve body (1) into an inlet cavity (12) and an outlet cavity (13), a through hole is formed in the partition plate (11), and the inlet cavity (12) is communicated with the outlet cavity (13) through the through hole;

the valve core (2) is connected with one end of the piston (3), the other end of the piston (3) is in sealing contact with the inner wall of the outlet cavity (13), the piston (3) can move on the inner wall of the outlet cavity (13), the valve core (2) can block the through hole, and the piston (3) can push the valve core (2) and can separate the valve core (2) from the through hole;

the valve body (1) is connected with the communicating piece (5) in a sealing mode, the adjusting device (4) is connected with the communicating piece (5) in a sealing mode, a membrane (6) is arranged between the adjusting device (4) and the communicating piece (5), a communicating cavity (51) is arranged inside the communicating piece (5), one end of the communicating cavity (51) is communicated with the outlet cavity (13), the other end of the communicating cavity (51) is communicated with the inlet cavity (12) through a conduit (10), and the communicating cavity (51) can be blocked by the membrane (6);

the pressure regulating valve has an open valve state and a closed valve state, when the pressure regulating valve is in the open valve state, the pressure of a medium in the inlet cavity (12) to the diaphragm (6) is greater than the pressure of the regulating device (4) to the diaphragm (6), part of the medium in the inlet cavity (12) enters the communicating cavity (51) through the conduit (10) and can push the diaphragm (6) to conduct the communicating cavity (51), the medium in the communicating cavity (51) can enter the outlet cavity (13) and can push the piston (3) to move to separate the valve core (2) from the through hole, and the medium in the inlet cavity (12) flows into the outlet cavity (13) through a gap between the valve core (2) and the through hole.

2. Pressure regulating valve according to claim 1, characterized in that the regulating means (4) comprises an upper bonnet (41), an elastic member (42), a pressure regulating member (43) and an upper bonnet (44), the upper valve cover (41) is connected with the communicating piece (5) in a sealing way, the elastic piece (42) is positioned in the upper valve cover (41), one end of the elastic piece (42) is abutted against the diaphragm (6), the other end of the elastic element (42) is connected with the pressure adjusting element (43), and the pressure adjusting element (43) can adjust the elastic force of the elastic element (42) acting on the diaphragm (6), the free end of the pressure regulating part (43) can extend out of the upper valve cover (41), the upper valve cover (41) is in threaded connection with the upper valve cap (44) and the upper valve cap (44) can cover the free end of the pressure regulating member (43).

3. The pressure regulating valve according to claim 2, wherein the elastic member (42) comprises a regulating spring (421), a lower spring seat (422), an upper spring seat (423), a steel ball (424) and a slider (425), the upper end of the regulating spring (421) is connected with the upper spring seat (423), the lower end of the regulating spring (421) is connected with the lower spring seat (422), the steel ball (424) is located between the slider (425) and the lower spring seat (422), and the slider (425) abuts against the diaphragm (6).

4. The pressure-regulating valve according to claim 2, wherein the pressure-regulating member (43) includes a pressure-regulating rod (431), a first bolt (432) and a first washer (433), the first bolt (432) and the first washer (433) are both embedded in the upper bonnet (41), the pressure-regulating rod (431) passes through the first bolt (432) and the first washer (433) in sequence and is connected with the elastic member (42), and the pressure-regulating rod (431) is threadedly connected with the first bolt (432).

5. Pressure regulating valve according to claim 1, characterized in that it further comprises a needle valve (7), said needle valve (7) being located at the side of said communicating member (5), one end of said needle valve (7) being insertable into said communicating member (5) and said needle valve (7) being in communication with said communicating chamber (51), said needle valve (7) being connectable with a measuring device.

6. The pressure regulating valve according to claim 1, wherein the piston (3) comprises a piston rod (31) and a piston block (32), the piston rod (31) is fixedly connected with the piston block (32), the free end of the piston rod (31) is connected with the valve core (2), the piston block (32) is in sealing contact with the inner wall of the outlet cavity (13), and the cross-sectional area of the piston block (32) is larger than that of the piston rod (31);

the piston block (32) is provided with a pressure relief hole (321).

7. The pressure regulating valve according to claim 1, further comprising a manual valve opening device (8), wherein the manual valve opening device (8) is connected with the valve body (1) in a sealing manner, the manual valve opening device (8) is connected with the valve core (2), and the manual valve opening device (8) can pull the valve core (2) away from the through hole.

8. The pressure-regulating valve according to claim 7, wherein the manual valve-opening device (8) includes a lower bonnet (81), a manual valve rod (82), a stop collar (83), a second bolt (84), a second gasket (85) and a lower bonnet (86), the lower bonnet (81) is connected with the valve body (1) in a sealing manner, the stop collar (83) is embedded in the valve core (2), the second bolt (84) and the second gasket (85) are embedded in the lower bonnet (81), the stop collar (83) is sleeved on one end of the manual valve rod (82) and the stop collar (83) limits the manual valve rod (82) to be separated from the stop collar (83), the free end of the manual valve rod (82) passes through the second gasket (85), the second bolt (84) and the lower bonnet (81), and the free end of the manual valve rod (82) extends out of the lower bonnet (81), the manual valve rod (82) is in threaded connection with the second bolt (84), the lower valve cap (86) is in threaded connection with the lower valve cap (81), and the lower valve cap (86) can cover the free end of the manual valve rod (82).

9. The pressure regulating valve according to claim 1, wherein the spool (2) comprises a positioning column (21), a connecting piece (22) and a limiting plate (23), one side of the connecting piece (22) is fixedly connected with the positioning column (21), the other side of the connecting piece (22) is fixedly connected with the limiting plate (23), the limiting plates (23) are distributed along the circumferential direction of the connecting piece (22), the piston (3) abuts against the connecting piece (22), and the limiting plate (23) and the piston (3) are positioned on the same side of the connecting piece (22);

and a mounting hole (211) is formed in the positioning column (21).

10. The pressure regulating valve according to claim 1, further comprising a return spring (9), wherein the return spring (9) is located in the inlet chamber (12), the return spring (9) is sleeved on the valve core (2), and the elastic force of the return spring (9) can move the valve core (2) until the valve core (2) blocks the through hole.