CN119860446A

CN119860446A - Duplex valve

Info

Publication number: CN119860446A
Application number: CN202510355824.9A
Authority: CN
Inventors: 余庭辉; 张良; 陈江顺; 王中明; 周建锋; 卢少义; 何俊毅; 王伟智
Original assignee: ZHEJIANG FANGDUN INSTRUMENT VALVE CO Ltd
Current assignee: ZHEJIANG FANGDUN INSTRUMENT VALVE CO Ltd
Priority date: 2025-03-25
Filing date: 2025-03-25
Publication date: 2025-04-22

Abstract

The present invention discloses a double valve, and specifically relates to the technical field of double valves, including a valve body, an upper valve cap, a lower valve cap, a valve core assembly and a valve seat assembly, the valve core assembly includes a lower valve stem arranged inside the lower valve cap, one end of the lower valve stem is provided with a sliding block, and the end of the lower valve stem close to the sliding block is provided with a valve core, a sliding groove is provided inside the valve core, and the sliding block can slide inside the sliding groove to make the valve core move in the direction of the center line of the lower valve stem. When the valve is opened, the valve core is first separated from a first sealing member and then moves in a direction away from the valve body. When the valve is closed, the valve core first contacts the valve body and then moves toward the first sealing member to squeeze the first sealing member, thereby reducing friction between the valve core and the first sealing member, thereby reducing wear between the valve core and the first sealing member when the valve body is switched, further increasing the service life of the valve, reducing the risk of leakage due to wear of the sealing member, and at the same time being able to give a prompt to the staff when the valve leaks.

Description

Duplex valve

Technical Field

The invention relates to the technical field of duplex valves, in particular to a duplex valve.

Background

In the application field of instrument valves or process valves, double valves play a critical role in double safety. Duplex valves are typically composed of two identical or similar valves that are cooperatively designed and connected in a manner that allows for the cooperative operation. When one valve fails or leaks, the other valve can immediately take over the work, so that the normal operation of the system is ensured, and safety accidents such as system shutdown and leakage caused by single valve failure are effectively avoided. The double-insurance design greatly improves the reliability and stability of the system, and is particularly suitable for industries such as chemical industry, petroleum, natural gas and the like with extremely high requirements on safety and continuity.

However, in the prior art, when the valve body is opened and closed, the valve rod drives the valve core to synchronously rotate, so that certain abrasion is caused to the sealing element of the valve, and when the valve core is about to leave and clamp the sealing element, the sealing element and the valve core are in close contact with each other, so that the abrasion degree of the sealing element is greatly increased, the service life is influenced, and meanwhile, the rotating resistance of the handle when the valve is opened is increased.

In addition, although the double-connected valve effectively prevents safety accidents caused by leakage of a single valve through double insurance, when one valve core of the double-connected valve is leaked, if the whole double-connected valve is possibly leaked due to untimely maintenance, the existing double-connected valve cannot prompt staff, and meanwhile, no emergency remedy measures exist when the single valve core of the double-connected valve is leaked, so that the double-connected valve is provided for solving the problems.

Disclosure of Invention

In order to overcome the above-mentioned drawbacks of the prior art, embodiments of the present invention provide a duplex valve to solve the problems set forth in the background art.

The double-valve comprises a valve body, an upper valve cap, a lower valve cap, a valve core assembly and a valve seat assembly, wherein the valve core assembly comprises a lower valve rod arranged in the lower valve cap, a sliding block is arranged at one end of the lower valve rod, a valve core is arranged at one end of the lower valve rod, which is close to the sliding block, the inner part of the valve core is provided with a sliding groove, the sliding block can slide in the sliding groove to enable the valve core to move towards the central line direction of the valve rod, the valve seat assembly comprises a first sealing element arranged in the valve body, the first sealing element can be matched with the valve core to seal the valve body, and the valve seat assembly also comprises a detecting element arranged in the valve body, when the valve body leaks, the detecting element can float due to medium pressure, and further the pressure in the first sealing element is increased to squeeze the valve core.

Preferably, one end of the lower valve rod, which is close to the valve body, is fixedly connected with a wedge block, the wedge block is fixedly connected with the sliding block, and the valve cores are at least two and are symmetrically distributed along the central axis of the lower valve rod.

Preferably, one end of the lower valve rod, which is close to the wedge block, is fixedly connected with a first piston plate, the first piston plate is in sliding connection with the inner wall of the lower valve cap, when the valve is opened, the first piston plate can extrude gas in the lower valve cap, and the inner wall of the lower valve cap is provided with a third exhaust hole.

Preferably, an energy storage groove is formed in the valve body, a first air inlet hole is formed in the energy storage groove, a one-way valve and an overflow valve are arranged at the first air inlet hole, and a first air outlet hole is formed in the energy storage groove.

Preferably, the valve core assembly further comprises an upper valve rod arranged in the upper valve cap, one end of the upper valve rod is fixedly connected with a connecting column, a connecting groove is formed in the connecting column, one end of the lower valve rod, which is far away from the wedge block, is fixedly connected with a connecting disc, the connecting disc is in sliding connection with the connecting groove, the connecting column is in sliding connection with the inner wall of the upper valve cap, and one end of the upper valve rod, which is far away from the lower valve rod, penetrates through the upper valve cap and is in threaded connection with the upper valve cap.

Preferably, one end of the connecting column far away from the lower valve rod is fixedly connected with a second piston plate, the second piston plate is in sliding connection with the upper valve cap, a second air inlet hole and a second air outlet hole are formed in the inner wall of the upper valve cap, and the second air outlet hole is communicated with the first air inlet hole of the energy storage groove.

Preferably, the valve body is internally provided with a detection groove, the bottom of the detection groove is provided with a detection hole, the detection piece can seal the detection hole, a third piston plate is slidably connected in the detection groove, one end of the third piston plate, which is far away from the detection piece, is fixedly connected with a warning column, a first elastic piece is arranged in the detection groove, one end of the first elastic piece is fixedly connected with the inner wall of the detection groove, and the other end of the first elastic piece is fixedly connected with one end of the third piston plate, which is close to the warning column.

Preferably, a limit groove is formed in the valve body, a limit column is slidably connected in the limit groove, the limit groove is communicated with the third exhaust hole, the limit groove is communicated with the detection groove, and the limit column can limit the third piston plate through sliding.

Preferably, a sealing groove is formed in the valve body, a second sealing piece is connected in the sealing groove in a sliding mode, the sealing groove is communicated with the detection groove through a pipeline, a through hole is formed in one end of the second sealing piece, and the second sealing piece can enable the first exhaust hole to be communicated with the first sealing piece through the through hole through sliding.

Preferably, the valve body is provided with two lower valve caps, the two lower valve caps are respectively and fixedly connected to two ends of the same side face of the valve body, the two upper valve caps are respectively, and one end of each upper valve cap is fixedly connected with one end, away from the valve body, of the corresponding lower valve cap.

The invention has the technical effects and advantages that:

1. According to the invention, the lower valve rod only moves linearly along with the upper valve rod, so that abrasion caused by relative rotation between the valve core and the first sealing element is reduced, the service life of the duplex valve is prolonged, and meanwhile, the resistance when the valve is opened and closed is reduced, so that the valve is smoother when the valve is opened and closed.

2. According to the invention, when the valve is opened, the valve core is separated from the first sealing element and moves in a direction away from the valve body, and when the valve is closed, the valve core is contacted with the valve body and then moves towards the first sealing element to squeeze the first sealing element, so that friction between the valve core and the first sealing element is reduced, abrasion between the valve core and the first sealing element when the valve body is opened and closed is reduced, the service life of the valve is further prolonged, and the risk of leakage caused by abrasion of the sealing element is reduced.

3. According to the valve, the warning column extends out of the valve body to prompt a worker, and meanwhile, the sealing performance between the first sealing element and the valve core is enhanced by increasing the internal pressure of the first sealing element, so that the situation that the worker cannot be timely prompted when one valve core of the valve is leaked due to abrasion is prevented, and meanwhile, serious safety accidents or larger losses caused by the fact that the valve is not provided with emergency measures are avoided.

Drawings

Fig. 1 is a schematic diagram of the overall structure of the present invention.

Fig. 2 is a cross-sectional view of the overall structure of the present invention in a closed state.

Fig. 3 is an enlarged view of the structure of the portion a of fig. 2 according to the present invention.

Fig. 4 is an enlarged view of the B-section structure of fig. 2 according to the present invention.

Figure 5 is a cross-sectional view of the accumulator tank and seal groove configuration of the present invention.

Fig. 6 is a cross-sectional view of a first seal configuration of the present invention.

FIG. 7 is a cross-sectional view of the overall structure of the upper stem of the present invention.

FIG. 8 is a schematic view of the overall structure of the lower stem of the present invention.

Fig. 9 is a schematic diagram of the overall structure of the valve core of the present invention.

Fig. 10 is a cross-sectional view of the overall structure of the open state of the present invention.

The valve comprises the following components of 1, a valve body, 11, an energy storage groove, 111, a first air inlet hole, 112, a first air outlet hole, 12, a limit groove, 121, a limit column, 2, an upper valve cap, 21, a second air inlet hole, 22, a second air outlet hole, 3, a lower valve cap, 31, a third air outlet hole, 4, a valve core assembly, 41, a lower valve rod, 411, a wedge block, 412, a first piston plate, 413, a connecting disc, 42, a sliding block, 43, a valve core, 431, a sliding groove, 44, an upper valve rod, 441, a connecting column, 442, a connecting groove, 443, a second piston plate, 5, a valve seat assembly, 51, a first sealing element, 52, a detecting element, 53, a detecting groove, 531, a detecting hole, 532, a first elastic element, 54, a third piston plate, 541, a warning column, 55, a sealing groove, 551 and a second sealing element.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

Example 1

In the actual production process, as the valve body 1 is opened and closed, the valve rod drives the valve core to synchronously rotate, a certain abrasion is caused on a sealing element of the valve, the service life is influenced, and meanwhile, the resistance of the handle to rotate is increased.

Referring to fig. 1 to 10, the duplex valve according to an embodiment of the invention includes a valve body 1, an upper bonnet 2, a lower bonnet 3, a valve core assembly 4 and a valve seat assembly 5, wherein the valve core assembly 4 includes a lower valve rod 41 disposed inside the lower bonnet 3, a slider 42 is disposed at one end of the lower valve rod 41, a valve core 43 is disposed at one end of the lower valve rod 41 near the slider 42, a sliding groove 431 is disposed inside the valve core 43, the slider 42 is capable of sliding inside the sliding groove 431 to move the valve core 43 toward a center line of the lower valve rod 41, the valve seat assembly 5 includes a first sealing member 51 disposed inside the valve body 1, the first sealing member 51 can cooperate with the valve core 43 to seal the valve body 1, the valve seat assembly 5 further includes a detecting member 52 disposed inside the valve body 1, and when the valve body 1 leaks, the detecting member 52 can float due to a medium pressure, so that the pressure inside the first sealing member 51 is increased to squeeze the valve core 43, wherein an outer wall of the first sealing member 51 is made of an elastic material.

Referring to fig. 2 and 3, one end of the lower valve rod 41, which is close to the valve body 1, is fixedly connected with a wedge block 411, the wedge block 411 is fixedly connected with a slider 42, at least two valve cores 43 are symmetrically distributed along the central axis of the lower valve rod 41, one end of the lower valve rod 41, which is close to the wedge block 411, is fixedly connected with a first piston plate 412, the first piston plate 412 is slidably connected with the inner wall of the lower valve cap 3, when the valve is opened, the first piston plate 412 can squeeze gas inside the lower valve cap 3, and the inner wall of the lower valve cap 3 is provided with a third exhaust hole 31.

Referring to fig. 5, an energy storage tank 11 is provided in the valve body 1, a first air inlet 111 is provided in the energy storage tank 11, a check valve and an overflow valve are provided at the first air inlet 111, and a first air outlet 112 is provided in the energy storage tank 11.

Referring to fig. 2 and 7, the valve core assembly 4 further includes an upper valve rod 44 disposed inside the upper bonnet 2, one end of the upper valve rod 44 is fixedly connected with a connection post 441, a connection slot 442 is formed inside the connection post 441, one end of the lower valve rod 41 away from the wedge 411 is fixedly connected with a connection disc 413, the connection disc 413 is slidably connected with the connection slot 442, the connection post 441 is slidably connected with an inner wall of the upper bonnet 2, one end of the upper valve rod 44 away from the lower valve rod 41 penetrates through the upper bonnet 2 and is in threaded connection with the upper bonnet 2, one end of the connection post 441 away from the lower valve rod 41 is fixedly connected with a second piston plate 443, the second piston plate 443 is slidably connected with the upper bonnet 2, a second air inlet hole 21 and a second air outlet hole 22 are formed in an inner wall of the upper bonnet 2, the second air outlet hole 22 is communicated with the first air inlet hole 111 of the energy storage slot 11, and one end of the upper valve rod 44 away from the connection post 441 is fixedly connected with a handle.

Referring to fig. 2 and 4, a detection groove 53 is formed in the valve body 1, a detection hole 531 is formed in the bottom of the detection groove 53, a detection member 52 is capable of sealing the detection hole 531, a third piston plate 54 is slidably connected in the detection groove 53, an alarm column 541 is fixedly connected to one end of the third piston plate 54 away from the detection member 52, a first elastic member 532 is disposed in the detection groove 53, one end of the first elastic member 532 is fixedly connected to an inner wall of the detection groove 53, and the other end of the first elastic member 532 is fixedly connected to one end of the third piston plate 54 close to the alarm column 541.

Referring to fig. 4, a limiting groove 12 is formed in the valve body 1, a limiting post 121 is slidably connected in the limiting groove 12, the limiting groove 12 is communicated with the third exhaust hole 31, the limiting groove 12 is communicated with the detecting groove 53, and the limiting post 121 can limit the third piston plate 54 through sliding.

Referring to fig. 5, a sealing groove 55 is formed in the valve body 1, a second sealing member 551 is slidably connected in the sealing groove 55, the sealing groove 55 is communicated with the detecting groove 53 through a pipeline, a through hole is formed at one end of the second sealing member 551, and the second sealing member 551 can enable the first exhaust hole 112 to be communicated with the first sealing member 51 through the through hole through sliding.

Referring to fig. 10, the number of the lower valve caps 3 is two, and the two ends of the same side of the valve body 1 are respectively fixedly connected, the number of the upper valve caps 2 is two, one end of each upper valve cap 2 is fixedly connected with one end of the corresponding lower valve cap 3, which is far away from the valve body 1, the sealing gasket is arranged between the upper valve cap 2 and the lower valve cap 3, one end of the lower valve cap 3, which is far away from the valve body 1, is provided with a locking nut, and the locking nut is in threaded connection with the upper valve cap 2 for locking the upper valve cap 2.

When the valve is opened from the closed state, the rotating handle drives the upper valve rod 44 to rotate in the upper valve cap 2, so that the upper valve rod 44 moves in a direction away from the valve body 1, the lower valve rod 41 drives the valve core 43 to move in a direction away from the valve body 1, the valve core 43 does not press the first sealing piece 51 any more, and the valve is opened, otherwise, when the valve is closed from the opened state, the rotating handle rotates the handle in the opposite direction, so that the upper valve rod 44 drives the lower valve rod 41 to move in a direction close to the valve body 1, the valve core 43 moves downwards, the first sealing piece 51 is pressed, the valve is closed, and the upper valve rod 44 and the lower valve rod 41 are connected in a rotating mode through the connecting groove 442 and the connecting disc 413, so that the lower valve rod 41 only moves linearly along with the upper valve rod 44, and abrasion caused by relative rotation between the valve core 43 and the first sealing piece 51 is reduced.

Example two

In practical use, it is found that when the valve core 43 leaves and presses the first sealing member 51, the valve core 43 still causes great abrasion to the first sealing member 51 due to the close contact between the valve core 43 and the first sealing member 51, and further improvement is made on the basis of the above embodiment.

On the basis of the above embodiment, when the valve is opened from the closed state, the upper valve rod 44 is driven by the rotating handle to move the lower valve rod 41 in a direction away from the valve body 1 by rotating the handle, so that the lower valve rod 41 is driven by the lower valve rod 41 to move in a direction away from the valve body 1, the sliding block 42 is driven to slide in the sliding groove 431 of the valve core 43 by the movement of the wedge block 411, so that the valve core 43 moves in the center line direction of the lower valve rod 41, so that the valve core 43 is not contacted with the first sealing member 51 any more, when the sliding block 42 moves to the limit position, the sliding block 42 is driven by continuing to rotate the handle, so that the valve core 42 drives the valve core 43 to move in a direction away from the valve body 1, so that the valve is opened, otherwise, when the valve is closed from the open state, the upper valve rod 44 drives the lower valve rod 41 to move in a direction close to the valve body 1, so that the valve core 43 moves in a direction close to the valve body 1, and when the valve core 43 moves to be contacted with the valve body 1, the sliding block 411 is driven by continuing to slide in the sliding groove 431 in the valve core 43, so that the valve core 43 moves in the direction away from the first sealing member 431, so that the valve core 43 moves in the direction away from the valve rod, so that the first sealing member 51 is pressed in a direction away from the valve core 51, and the first sealing member is pressed against the first sealing member 51, and the first sealing member 51 is pressed against the first sealing member and the first sealing member 51 when the first sealing member is opened, and then the first sealing member is opened.

Example III

In practical use, it was found that when one of the valve spools 43 leaks due to wear of the first seal 51, no prompt can be given to the operator, and no emergency treatment can be performed on the sealing portion, which is prone to further leakage, and further improvements are made on the basis of the above embodiments.

In use, when the valve is opened from the closed state, the handle is turned to enable the upper valve rod 44 to move in a direction away from the valve body 1, so that the second piston plate 443 presses the gas inside the upper valve cap 2, so that the gas inside the upper valve cap 2 enters the energy storage tank 11 through the second exhaust hole 22 via the first air inlet hole 111, the upper valve rod 44 moves in a direction away from the valve body 1 and simultaneously drives the lower valve rod 41 to move upwards, so that the first piston plate 412 presses the gas inside the lower valve cap 3, so that the gas inside the lower valve cap 3 enters the limit tank 12, so that the limit column 121 moves inwards the detection tank 53, so that the limit column 121 limits the third piston plate 54, so that when the valve is opened, the valve body 1 increases in pressure to enable the detection member 52 to drive the third piston plate 54 to slide upwards, when the valve is closed from the open state, rotating the handle causes the upper valve rod 44 to drive the lower valve rod 41 to move in a direction approaching the valve body 1, so that the first piston plate 412 moves in the opposite direction inside the lower valve cap 3, so that the gas inside the limit groove 12 enters the inside of the lower valve cap 3, so that the limit post 121 moves in a direction away from the detection groove 53, when one of the valve cores 43 leaks, the medium enters the inside of the valve body 1, so that the pressure inside the valve body 1 is continuously increased, and the limit post 121 does not limit the third piston plate 54 because the valve is in a closed state, at this time, the medium in the pipe inside of the valve body 1 gradually increases to cause the detection piece 52 to float upwards, the third piston plate 54 is driven to move inside the detection groove 53 by the upward floating of the detection piece 52, so that the gas inside the detection groove 53 enters the inside of the seal groove 55, so that the second seal 551 moves inside the seal groove 55, therefore, the second sealing piece 551 does not seal the first exhaust hole 112 any more, so that gas in the energy storage tank 11 enters the first sealing piece 51, the internal pressure of the first sealing piece 51 is increased, the first sealing piece 51 further presses the valve core 43, the tightness of the valve body 1 is improved, the third piston plate 54 moves upwards and drives the warning column 541 to move upwards, the warning column 541 extends out of the valve body 1, when one valve core 43 of the valve leaks, the warning column 541 extends out of the valve body 1 to prompt a worker, and meanwhile, the tightness between the first sealing piece 51 and the valve core 43 is increased to prevent the valve from further leaking.

The foregoing is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art, who is within the scope of the present invention, should make equivalent substitutions or modifications according to the technical scheme of the present invention and the inventive concept thereof, and should be covered by the scope of the present invention.

Claims

1. The utility model provides a duplex valve, includes valve body (1), goes up bonnet (2) and lower bonnet (3), its characterized in that still includes:

The valve core assembly (4), the valve core assembly (4) comprises a lower valve rod (41) arranged in a lower valve cap (3), a sliding block (42) is arranged at one end of the lower valve rod (41), a valve core (43) is arranged at one end, close to the sliding block (42), of the lower valve rod (41), a sliding groove (431) is formed in the valve core (43), and the sliding block (42) can enable the valve core (43) to move towards the central line direction of the lower valve rod (41) through sliding in the sliding groove (431);

the valve seat assembly (5), valve seat assembly (5) are including setting up at the inside first sealing member (51) of valve body (1), first sealing member (51) can cooperate with case (43) to seal valve body (1), valve seat assembly (5) are still including setting up at inside detecting piece (52) of valve body (1), when leakage takes place for valve body (1), detecting piece (52) can float because of medium pressure produces, and then makes the inside pressure increase extrusion case (43) of first sealing member (51).

2. The duplex valve according to claim 1, wherein one end of the lower valve rod (41) close to the valve body (1) is fixedly connected with a wedge block (411), the wedge block (411) is fixedly connected with the sliding block (42), and the valve cores (43) are at least two and symmetrically distributed along the central axis of the lower valve rod (41).

3. The duplex valve according to claim 2, wherein one end of the lower valve rod (41) close to the wedge-shaped block (411) is fixedly connected with a first piston plate (412), the first piston plate (412) is slidably connected with the inner wall of the lower valve cap (3), when the valve is opened, the first piston plate (412) can squeeze gas in the lower valve cap (3), and a third exhaust hole (31) is formed in the inner wall of the lower valve cap (3).

4. The duplex valve according to claim 3, wherein the valve body (1) is internally provided with an energy storage groove (11), a first air inlet hole (111) is formed in the energy storage groove (11), a one-way valve and an overflow valve are arranged at the first air inlet hole (111), and a first air outlet hole (112) is formed in the energy storage groove (11).

5. The duplex valve of claim 4, wherein the valve core assembly (4) further comprises an upper valve rod (44) arranged in the upper valve cap (2), one end of the upper valve rod (44) is fixedly connected with a connecting column (441), a connecting groove (442) is formed in the connecting column (441), one end, far away from the wedge-shaped block (411), of the lower valve rod (41) is fixedly connected with a connecting disc (413), the connecting disc (413) is in sliding connection with the connecting groove (442), the connecting column (441) is in sliding connection with the inner wall of the upper valve cap (2), and one end, far away from the lower valve rod (41), of the upper valve rod (44) penetrates through the upper valve cap (2) and is in threaded connection with the upper valve cap (2).

6. The double valve according to claim 5, wherein a second piston plate (443) is fixedly connected to one end of the connecting column (441) far away from the lower valve rod (41), the second piston plate (443) is slidably connected with the upper valve cap (2), a second air inlet hole (21) and a second air outlet hole (22) are formed in the inner wall of the upper valve cap (2), and the second air outlet hole (22) is communicated with the first air inlet hole (111) of the energy storage groove (11).

7. The duplex valve of claim 6, wherein the valve body (1) is internally provided with a detection groove (53), the bottom of the detection groove (53) is provided with a detection hole (531), the detection piece (52) can seal the detection hole (531), a third piston plate (54) is slidably connected in the detection groove (53), one end, far away from the detection piece (52), of the third piston plate (54) is fixedly connected with a warning column (541), a first elastic piece (532) is arranged in the detection groove (53), one end of the first elastic piece (532) is fixedly connected with the inner wall of the detection groove (53), and the other end of the first elastic piece (532) is fixedly connected with one end, close to the warning column (541), of the third piston plate (54).

8. The duplex valve according to claim 7, wherein a limiting groove (12) is formed in the valve body (1), a limiting post (121) is slidably connected in the limiting groove (12), the limiting groove (12) is communicated with the third exhaust hole (31), the limiting groove (12) is communicated with the detection groove (53), and the limiting post (121) can limit the third piston plate (54) through sliding.

9. The duplex valve according to claim 8, wherein a sealing groove (55) is formed in the valve body (1), a second sealing piece (551) is connected in the sealing groove (55) in a sliding mode, the sealing groove (55) is communicated with the detection groove (53) through a pipeline, a through hole is formed in one end of the second sealing piece (551), and the second sealing piece (551) can enable the first exhaust hole (112) to be communicated with the first sealing piece (51) through the through hole through sliding.

10. The duplex valve according to claim 9, wherein the number of the lower valve caps (3) is two, the lower valve caps (3) are respectively and fixedly connected to two ends of the same side face of the valve body (1), the number of the upper valve caps (2) is two, and one end of each upper valve cap (2) is fixedly connected with one end, away from the valve body (1), of the corresponding lower valve cap (3).