CN216131439U

CN216131439U - Gas self-closing valve

Info

Publication number: CN216131439U
Application number: CN202122528900.1U
Authority: CN
Inventors: 王志乐
Original assignee: Taizhou Tongyang Pipe Co ltd
Current assignee: Taizhou Tongyang Pipe Co ltd
Priority date: 2021-10-20
Filing date: 2021-10-20
Publication date: 2022-03-25
Anticipated expiration: 2031-10-20

Abstract

The utility model provides a gas self-closing valve, and belongs to the technical field of gas valves. It has solved the inconvenient pressure measurement scheduling problem of current gas self-closing valve. This gas self-closing valve includes the valve body, the valve gap, valve rod and plunger, be equipped with the open-close valve of control gas outlet switch on the valve body, link firmly on the valve body with the communicating pressure measurement joint of gas outlet, pressure measurement articulate has stifled cap, be equipped with the rubber pad in the stifled cap, be equipped with the uide bushing in the pressure measurement joint, be equipped with seal structure between uide bushing and the pressure measurement joint, the uide bushing axial is worn to be equipped with the pressure measurement pole, the top cover that the pressure measurement pole stretches out the uide bushing upper end is equipped with the spring, the bottom that the pressure measurement pole stretches out the uide bushing lower extreme inlays and is equipped with the sealing ring, the spring is contradicted the pier nose and is provided elasticity and makes the sealing ring keep the trend of sealing in the uide bushing lower extreme, the gas clearance has between uide bushing and the pressure measurement pole, the top of uide bushing radially link up there is the gas hole of crossing in the gas clearance. The utility model has the advantages of convenient pressure measurement, convenient installation and arrangement and the like.

Description

Gas self-closing valve

Technical Field

The utility model belongs to the technical field of gas valves, and particularly relates to a gas self-closing valve.

Background

The gas self-closing valve is a device which is arranged on a low-pressure gas pipeline, does not need electric power or other external power when the gas supply pressure of the pipeline is under-pressure or over-pressure, and can be automatically closed and manually opened.

For example, chinese patent literature discloses a gas self-closing valve [ application No.: 201921701586.9, respectively; authorization notice number: CN210770399U ], which comprises a valve body and a valve cover, wherein the left end of the valve body is provided with an air inlet, the right end of the valve body is provided with an air outlet, the inner cavity of the valve body is provided with a vertical air passing channel at the middle position, the side of the vertical air passing channel is provided with a side opening communicated with the air inlet, the resisting part of the vertical air passing channel is provided with a top opening communicated with the inner cavity of the valve body, the inner cavity of the valve body is provided with an opening at the right side position communicated with the air outlet, the valve cover is arranged above the vertical air passing channel to cover the upper opening of the inner cavity of the valve body and is fixedly connected with the valve body, the upper part of the valve cover is movably provided with a valve handle which is fixedly connected with a shaft lever, the lower rod end of the shaft lever enters the inner cavity of the valve body and is connected with a leather cup, the top of the valve cover is connected with a guide sleeve, the guide sleeve is internally provided with a fixed gasket and a movable permanent magnet, the gasket and the permanent magnet can be magnetically absorbed, the permanent magnet is connected with the shaft lever to move up and down together, a heat-sensitive piece and a copper ring limited by the heat-sensitive piece are arranged between the leather cup, the upper part of the copper ring is provided with a compression spring.

The gas self-closing valve can realize the automatic relation between gas cut-off and high temperature, but in the using process, the pressure can not be measured, whether the pressure of a gas pipeline is abnormal or not can not be rapidly detected, and the gas self-closing valve does not have the opening and closing function, so that the opening and closing valve is additionally arranged on the pipeline, and the gas self-closing valve is inconvenient to install and arrange.

Disclosure of Invention

The utility model aims to solve the problems in the prior art and provides a gas self-closing valve which is convenient for pressure measurement and installation and arrangement.

The purpose of the utility model can be realized by the following technical scheme: the utility model provides a gas self-closing valve, includes valve body, valve gap, valve rod and plunger, the valve body have air inlet and gas outlet, have in the valve body to separate its inner chamber for the baffle of epicoele and cavity of resorption and the baffle has the gas passing hole of intercommunication epicoele and cavity of resorption, the epicoele is linked together with the gas outlet, cavity of resorption and air inlet are linked together, valve body and valve gap between the clamp have with the sealed diaphragm of epicoele, the inner of valve rod passes the diaphragm middle part and links firmly mutually with the diaphragm, the outer end of valve rod is worn out the valve gap and is connected with the handle, the baffle have the supporting seat that is the tube-shape and extends in the epicoele, the supporting seat has the air vent that radially runs through, the top of supporting seat link firmly the metal sheet, the bottom of plunger link firmly sealed the pad, the top of plunger is worn out the metal sheet and is linked firmly magnet, its characterized in that the valve body on be equipped with the on-off valve of control gas outlet switch, the valve body on link firmly with the communicating pressure measurement joint of gas outlet, the outer end threaded connection that the pressure measurement connects the exposure valve body have stifled cap, stifled cap in be equipped with the rubber pad sealed in pressure measurement joint tip, the pressure measurement connect in be equipped with the uide bushing that is the tube-shape, uide bushing and pressure measurement connect between be equipped with seal structure, the uide bushing axial wear to be equipped with the pressure measurement pole, the pressure measurement pole stretch out the top cover of uide bushing upper end and be equipped with the pier nose that spring and pressure measurement pole have radial evagination, the pressure measurement pole stretches out the bottom of uide bushing lower extreme and inlays and be equipped with the sealing ring, the spring conflict pier nose and provide elasticity and make the sealing ring keep sealing in the trend of uide bushing lower extreme, have the gas clearance between uide bushing and the pressure measurement pole, the top of uide bushing radially link up has the gas passing hole that communicates in the gas clearance.

In the gas self-closing valve, the outer wall of the guide sleeve is embedded with a clamp spring, and the inner wall of the pressure measuring joint is provided with an annular groove for the clamp spring to be clamped in.

In the gas self-closing valve, the sealing structure comprises a first rubber sleeve and a second rubber sleeve which are sleeved outside the guide sleeve, and the outer walls of the first rubber sleeve and the second rubber sleeve are sealed on the inner wall of the pressure measuring joint.

In the gas self-closing valve, the middle part of the outer wall of the guide sleeve is provided with a conical surface section which is radially outwards convex, the outer wall of the conical surface section is a conical surface, the outer diameter of the lower end of the conical surface section is smaller than the outer diameter of the upper end of the conical surface section, and the inner wall of the pressure measuring joint is provided with an inner conical surface for the conical surface section to be attached.

In foretell gas self-closing valve, the valve that opens and shuts be the ball valve, the ball valve includes ball core, the body of rod and hand wheel, the ball core be arranged in the gas outlet, the ball valve both sides all are equipped with seal ring, the gas outlet has the joint that compresses tightly outside seal ring through female connection, the inner of the body of rod links firmly mutually with the ball core, the outer end of the body of rod stretches out the valve body and links firmly mutually with the hand wheel, the valve body has radial convex spacing arch, the hand wheel lower part have the stopper of two evaginations, the contained angle between two stoppers be 90 and spacing arch is located between two stoppers.

In the gas self-closing valve, the position of the valve body, through which the rod body penetrates, is fixedly connected with an identification plate, the identification plate is provided with an opening character and a closing character, the hand wheel covers the identification plate, and the hand wheel is provided with a window which penetrates through the hand wheel to display the opening or the closing.

In the gas self-closing valve, the gas inlet is internally provided with the overflowing valve core, the overflowing valve core comprises a valve core body, a first connecting seat and a second connecting seat, the first connecting seat and the second connecting seat are both in a cylindrical shape, the first connecting seat is sleeved on the second connecting seat, the gas inlet is connected with a connector for compressing the first connecting seat through internal threads, the inner wall of the first connecting seat is connected with a first guide sleeve through ribs which are uniformly distributed in the circumferential direction, the inner wall of the second connecting seat is connected with a second guide sleeve through ribs which are uniformly distributed in the circumferential direction, the outer end of the valve core body is arranged in the first guide sleeve in a penetrating mode, the inner end of the valve core body is arranged in the second guide sleeve in a penetrating mode, the valve core body is provided with a radially convex blocking portion, and the valve core body is sleeved with a pressure spring which is located between the blocking portion and the second guide sleeve.

Compared with the prior art, the gas self-closing valve has the advantages of compact structure, convenience in installation and arrangement, convenience in pressure measurement, convenience in maintenance, good working stability and long service life.

Drawings

Fig. 1 is a three-dimensional structure view of the gas self-closing valve.

FIG. 2 is a structural section view of the gas self-closing valve.

FIG. 3 is a structural section view of the pressure measuring joint of the gas self-closing valve.

FIG. 4 is a schematic structural diagram of the removal hand wheel of the gas self-closing valve.

Fig. 5 is a structural schematic diagram of a hand wheel in the gas self-closing valve.

In the figure, 1, a valve body; 2. a valve cover; 3. a valve stem; 4. a plunger; 5. an air inlet; 6. an air outlet; 7. a partition plate; 8. a membrane; 9. a handle; 10. a supporting seat; 11. a metal plate; 12. a gasket; 13. a magnet; 14. a pressure measuring joint; 15. a plugging cap; 16. a rubber pad; 17. a guide sleeve; 18. a pressure measuring rod; 19. a spring; 20. a seal ring; 21. air passing holes; 22. a clamp spring; 23. a first rubber sleeve; 24. a second rubber sleeve; 25. a conical surface section; 26. a ball core; 27. a rod body; 28. a hand wheel; 29. a sealing gasket; 30. a limiting bulge; 31. a limiting block; 32. a marking plate; 33. a window; 34. a valve core body; 35. a first connecting seat; 36. a second connecting seat; 37. a first guide sleeve; 38. a second guide sleeve; 39. and (5) pressing a spring.

Detailed Description

The following are specific embodiments of the present invention and are further described with reference to the drawings, but the present invention is not limited to these embodiments.

As shown in fig. 1, 2 and 3, the gas self-closing valve comprises a valve body 1, a valve cover 2, a valve rod 3 and a plunger 4, wherein the valve body 1 is provided with an air inlet 5 and an air outlet 6, a partition plate 7 for dividing the inner cavity of the valve body 1 into an upper cavity and a lower cavity is arranged in the valve body 1, the partition plate 7 is provided with an air passing hole 21 for communicating the upper cavity and the lower cavity, the upper cavity is communicated with the air outlet 6, the lower cavity is communicated with the air inlet 5, a diaphragm 8 for sealing the upper cavity is clamped between the valve body 1 and the valve cover 2, the inner end of the valve rod 3 penetrates through the middle part of the diaphragm 8 and is fixedly connected with the diaphragm 8, the outer end of the valve rod 3 penetrates through the valve cover 2 and is connected with a handle 9, the partition plate 7 is provided with a cylindrical supporting seat 10 extending into the upper cavity, the supporting seat 10 is provided with an air passing hole penetrating in the radial direction, the top of the supporting seat 10 is fixedly connected with a metal plate 11, the bottom end of the plunger 4 is fixedly connected with a sealing gasket 12, the top end of the plunger 4 penetrates through the metal plate 11 and is fixedly connected with a magnet 13, in the embodiment, a bolt penetrates through a magnet 13 and is fixedly connected with a plunger 4 so as to fixedly connect the magnet 13 on the plunger 4, a valve opening and closing valve for controlling the opening and closing of an air outlet 6 is arranged on a valve body 1, a pressure measuring joint 14 communicated with the air outlet 6 is fixedly connected on the valve body 1, a plugging cap 15 is connected with the outer end of the pressure measuring joint 14, which is exposed out of the valve body 1, through threads, a rubber pad 16 sealed at the end part of the pressure measuring joint 14 is arranged in the plugging cap 15, a tubular guide sleeve 17 is arranged in the pressure measuring joint 14, a sealing structure is arranged between the guide sleeve 17 and the pressure measuring joint 14, a pressure measuring rod 18 is axially penetrated through the guide sleeve 17, a spring 19 is sleeved at the top of the upper end of the pressure measuring rod 18, a radially outward convex pier head is arranged at the top of the pressure measuring rod 18, a sealing ring 20 is embedded at the bottom of the lower end of the pressure measuring rod 18, the sealing ring 20 is provided with a convex ring for supporting the bottom of the sealing ring 20, the convex ring has good supporting performance for ensuring the sealing performance when the sealing ring 20, the spring 19 is abutted against the abutment head and provides elasticity to enable the sealing ring 20 to keep the trend of sealing the lower end of the guide sleeve 17, an air passing gap is formed between the guide sleeve 17 and the pressure measuring rod 18, and an air passing hole 21 communicated with the air passing gap is radially communicated with the top of the guide sleeve 17.

The gas self-closing valve can control the opening and closing of the gas outlet 6 through the arrangement of the opening and closing valves, reduces the number of the opening and closing valves arranged on a gas pipeline, and is compact in structure and convenient to install and arrange; before assembly, no pier head is arranged at the top of the pressure measuring rod 18, when the pressure measuring rod 18 and the guide sleeve 17 are assembled, the sealing ring 20 is firstly embedded on the pressure measuring rod 18, then the pressure measuring rod 18 penetrates through the lower end of the guide sleeve 17, the guide sleeve 17 extends out of the top of the pressure measuring rod 18, then the spring 19 is sleeved into the top of the pressure measuring rod 18, and then the pier head is processed at the top of the pressure measuring rod 18 to prevent the spring 19 from falling off.

The plug is in a locking state at ordinary times, the plug tightly presses the rubber pad 16, so that the rubber pad 16 is sealed at the end part of the pressure measuring joint 14, the spring 19 provides elasticity to enable the sealing ring 20 to be sealed at the lower end of the guide sleeve 17, the sealing structure ensures the sealing performance between the guide sleeve 17 and the pressure measuring joint 14, the sealing performance at the pressure measuring joint 14 is good, and the use safety is good; when pressure measurement is needed, the plug is rotated, the plug and the rubber pad 16 are taken down, the sealing ring 20 is still sealed at the lower end of the guide sleeve 17 at the moment, then the pressure measurement meter is in threaded connection with the pressure measurement connector 14, the ejector rod in the pressure measurement meter pushes against the pressure measurement rod 18 to overcome the elasticity of the spring 19, the pressure measurement rod 18 moves downwards in the axial direction, the sealing ring 20 is separated from the lower end of the guide sleeve 17, gas enters a gas passing gap from the lower end of the guide sleeve 17 and flows to the pressure measurement meter from the gas passing hole 21, pressure measurement work is completed, the pressure condition of a gas pipeline is convenient to detect, after detection, the pressure measurement meter is taken down, the spring 19 provides elasticity to enable the sealing ring 20 to be sealed at the lower end of the guide sleeve 17 again, the rubber pad 16 is placed at the end of the pressure measurement connector 14, and the plug is locked again.

In more detail, the outer wall of the guide sleeve 17 is embedded with a snap spring 22, and the inner wall of the pressure measuring joint 14 is provided with an annular groove for the snap spring 22 to be clamped in. During assembly, the guide sleeve 17 is inserted into the pressure measuring connector 14, the clamp spring 22 is blocked by the inner wall of the guide sleeve 17 and is embedded in the outer wall of the guide sleeve 17 until the clamp spring 22 is expanded and the outer ring of the clamp spring is clamped into the annular groove, the guide sleeve 17 and the pressure measuring connector 14 are assembled in place at the moment, the inner ring of the clamp spring 22 is still embedded in the outer wall of the guide sleeve 17, the guide sleeve 17 and the pressure measuring connector 14 cannot be separated, and positioning is stable.

The sealing structure comprises a first rubber sleeve 23 and a second rubber sleeve 24 which are sleeved outside the guide sleeve 17, the outer walls of the first rubber sleeve 23 and the second rubber sleeve 24 are sealed on the inner wall of the pressure measuring joint 14, the first rubber sleeve 23 is positioned above the second rubber sleeve 24, the first rubber sleeve 23 and the second rubber sleeve 24 play a double sealing role, and the sealing performance between the guide sleeve 17 and the pressure measuring joint 14 is good; the middle part of the outer wall of the guide sleeve 17 is provided with a radially outward convex conical surface section 25, the outer wall of the conical surface section 25 is a conical surface, the outer diameter of the lower end of the conical surface section 25 is smaller than the outer diameter of the upper end of the conical surface section 25, the inner wall of the pressure measuring joint 14 is provided with an inner conical surface for fitting the conical surface section 25, so that the guide sleeve 17 is fitted with the inner conical surface of the pressure measuring joint 14 through the conical surface section 25, a hard sealing effect is achieved, and the sealing performance is improved.

As shown in fig. 2, 4 and 5, the opening and closing valve in this embodiment is a ball valve, the ball valve includes a ball core 26, a rod 27 and a hand wheel 28, the ball core 26 is located in the air outlet 6, both sides of the ball valve are provided with sealing gaskets 29, the air outlet 6 is connected with a joint for compressing the outer sealing gaskets 29 through internal threads, the inner end of the rod 27 is fixedly connected with the ball core 26, the outer end of the rod 27 extends out of the valve body 1 and is fixedly connected with the hand wheel 28, the valve body 1 is provided with a radially protruding limiting protrusion 30, the lower portion of the hand wheel 28 is provided with two protruding limiting blocks 31, an included angle between the two limiting blocks 31 is 90 degrees, the limiting protrusion 30 is located between the two limiting blocks 31, the rod 27 is driven to rotate by the hand wheel 28, the rod 27 drives the ball core 26 to rotate, thereby controlling the opening and closing of the air outlet 6, the limiting protrusion 30 and the two limiting blocks 31 limit the rotation angle of the hand wheel 28, when one limiting block 31 abuts against the limiting protrusion 30, when the ball core 26 is in a closed state, the ball core 26 is in a completely opened state when the other limiting block 31 abuts against the limiting protrusion 30; the position of the valve body 1 for the rod body 27 to penetrate out is fixedly connected with an identification plate 32, in the embodiment, the outer wall of the position of the valve body 1 for the rod body 27 to penetrate out is provided with two symmetrical convex blocks, the identification plate 32 is sleeved on the position of the valve body 1 for the rod body 27 to penetrate out and is provided with a groove for the convex block to be embedded in, so that the identification plate 32 is fixedly connected on the position of the valve body 1 for the rod body 27 to penetrate out, the identification plate 32 is provided with an on character and an off character, a hand wheel 28 covers the identification plate 32 and the hand wheel 28 is provided with a window 33 which penetrates through to display on or off, when the window 33 of the hand wheel 28 displays off, one limiting block 31 is abutted against the limiting bulge 30, at the moment, the ball core 26 is in a closed state, the air outlet 6 is closed, otherwise, when the hand wheel 28 rotates 90 degrees and the window 33 of the hand wheel 28 displays on, the other limiting block 31 is abutted against the limiting bulge 30, at the moment, the ball core 26 is in a completely opened state, the air outlet 6 is maximally, thus, the observation is visual, and the operator can rapidly identify whether the air outlet 6 is closed.

Be equipped with the overcurrent valve core in the air inlet 5, the overcurrent valve core includes the valve core body 34, connecting seat one 35 and connecting seat two 36 all are the tube-shape and connecting seat one 35 overlaps on connecting seat two 36, air inlet 5 has the joint that compresses tightly connecting seat one 35 through female connection, the inner wall of connecting seat one 35 is connected with uide bushing one 37 through the floor of circumference equipartition, the inner wall of connecting seat two 36 is connected with uide bushing two 38 through the floor of circumference equipartition, the outer end of valve core body 34 is worn to locate in uide bushing one 37, the inner of valve core body 34 is worn to locate in uide bushing two 38, valve core body 34 has radial convex stop part, valve core body 34 cover is equipped with the pressure spring 39 that is located between stop part and uide bushing two 38. When the air inlet 5 admits air in right time, the gas passes through, the first connecting seat 35, the valve core body 34, the second connecting seat 36 and enters the upper cavity, and when the flow of the air inlet 5 is overlarge, the gas impacts the valve core body 34 and overcomes the elasticity of the pressure spring 39, so that the valve core body 34 moves towards the second connecting seat 36 side, the blocking part is sealed at the end part of the second connecting seat 36, the sealing effect is achieved, and the overcurrent protection effect is achieved.

Those not described in detail in this specification are within the skill of the art. The specific embodiments described herein are merely illustrative of the spirit of the utility model. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the utility model as defined in the appended claims.

Claims

1. The utility model provides a gas self-closing valve, includes valve body (1), valve gap (2), valve rod (3) and plunger (4), valve body (1) air inlet (5) and gas outlet (6) have in valve body (1) and separate baffle (7) and baffle (7) for epicoele and cavity of resorption for its inner chamber have intercommunication epicoele and cavity of resorption air vent (21), epicoele and gas outlet (6) are linked together, cavity of resorption and air inlet (5) are linked together, valve body (1) and valve gap (2) between the clamp have with epicoele sealed diaphragm (8), the inner of valve rod (3) passes diaphragm (8) middle part and links firmly mutually with diaphragm (8), valve gap (2) are worn out and handle (9) are connected to the outer end of valve rod (3), baffle (7) have and be the tube-shape and extend to supporting seat (10) in the epicoele, supporting seat (10) have the air vent that radially runs through, the top of supporting seat (10) linked firmly metal sheet (11), the bottom of plunger (4) linked firmly sealed pad (12), the top of plunger (4) is worn out metal sheet (11) and is linked firmly magnet (13), its characterized in that, valve body (1) on be equipped with the on-off valve of control gas outlet (6) switch, valve body (1) on linked firmly with communicating pressure measurement joint (14) in gas outlet (6), pressure measurement joint (14) the outer end threaded connection who exposes valve body (1) have stifled cap (15), stifled cap (15) in be equipped with sealed rubber pad (16) in pressure measurement joint (14) tip, pressure measurement joint (14) in be equipped with uide bushing (17) that is the tube-shape, uide bushing (17) and pressure measurement joint (14) between be equipped with seal structure, uide bushing (17) axial wear to be equipped with and measure pressure pole (18), the top that pressure measuring pole (18) stretched out uide bushing (17) upper end cover be equipped with spring (19) and pressure measuring pole (18) has the pier nose of radial evagination, pressure measuring pole (18) stretch out uide bushing (17) lower extreme bottom and inlay and be equipped with sealing ring (20), spring (19) conflict pier nose and provide elasticity and make sealing ring (20) keep sealing in the trend of uide bushing (17) lower extreme, have between uide bushing (17) and pressure measuring pole (18) and cross the gas clearance, the top of uide bushing (17) is radially link up there is gas passing hole (21) that communicate in gas passing clearance.

2. The gas self-closing valve as claimed in claim 1, characterized in that a snap spring (22) is embedded in the outer wall of the guide sleeve (17), and the inner wall of the pressure measuring joint (14) is provided with an annular groove for the snap spring (22) to be clamped in.

3. The gas self-closing valve according to claim 1 or 2, characterized in that the sealing structure comprises a first rubber sleeve (23) and a second rubber sleeve (24) which are sleeved outside the guide sleeve (17), and the outer walls of the first rubber sleeve (23) and the second rubber sleeve (24) are sealed on the inner wall of the pressure measuring joint (14).

4. The gas self-closing valve according to claim 3, characterized in that the middle part of the outer wall of the guide sleeve (17) is provided with a conical surface section (25) which is radially outwards convex, the outer wall of the conical surface section (25) is a conical surface, the outer diameter of the lower end of the conical surface section (25) is smaller than the outer diameter of the upper end of the conical surface section (25), and the inner wall of the pressure measuring joint (14) is provided with an inner conical surface for the conical surface section (25) to be attached.

5. The gas self-closing valve according to claim 4, characterized in that the opening and closing valve is a ball valve, the ball valve comprises a ball core (26), a rod body (27) and a hand wheel (28), the ball core (26) is positioned in the gas outlet (6), sealing gaskets (29) are arranged on two sides of the ball valve, the gas outlet (6) is connected with a joint for compressing the outer sealing gasket (29) through internal threads, the inner end of the rod body (27) is fixedly connected with the ball core (26), the outer end of the rod body (27) extends out of the valve body (1) and is fixedly connected with the hand wheel (28), the valve body (1) is provided with a radially convex limiting protrusion (30), two convex limiting blocks (31) are arranged on the lower portion of the hand wheel (28), an included angle between the two limiting blocks (31) is 90 degrees, and the limiting protrusion (30) is positioned between the two limiting blocks (31).

6. The gas self-closing valve according to claim 5, characterized in that the valve body (1) is fixedly connected with an identification plate (32) at the position where the rod body (27) penetrates out, the identification plate (32) is provided with characters of opening and closing, the hand wheel (28) covers the identification plate (32), and the hand wheel (28) is provided with a window (33) which penetrates through the hand wheel (28) and displays opening or closing.

7. The gas self-closing valve according to claim 6, characterized in that an overflowing valve core is arranged in the gas inlet (5), the overflowing valve core comprises a valve core body (34), a first connecting seat (35) and a second connecting seat (36), the first connecting seat (35) and the second connecting seat (36) are both cylindrical, the first connecting seat (35) is sleeved on the second connecting seat (36), the gas inlet (5) is connected with a joint for compressing the first connecting seat (35) through internal threads, the inner wall of the first connecting seat (35) is connected with a first guide sleeve (37) through ribs which are uniformly distributed in the circumferential direction, the inner wall of the second connecting seat (36) is connected with a second guide sleeve (38) through ribs which are uniformly distributed in the circumferential direction, the outer end of the valve core body (34) is arranged in the first guide sleeve (37) in a penetrating manner, the inner end of the valve core body (34) is arranged in the second guide sleeve (38) in a penetrating manner, and the valve core body (34) is provided with a blocking part which protrudes in the radial direction, the valve core body (34) is sleeved with a pressure spring (39) positioned between the blocking part and the second guide sleeve (38).