CN114658861A

CN114658861A - Diaphragm valve

Info

Publication number: CN114658861A
Application number: CN202210354789.5A
Authority: CN
Inventors: 黄文博; 陆文军; 聂敏
Original assignee: Kunshan Kinglai Hygienic Materials Co Ltd
Current assignee: Kunshan Kinglai Hygienic Materials Co Ltd
Priority date: 2022-04-06
Filing date: 2022-04-06
Publication date: 2022-06-24
Anticipated expiration: 2042-04-06
Also published as: CN114658861B

Abstract

The invention relates to the technical field of diaphragms, in particular to a diaphragm valve. The diaphragm valve comprises a valve body, a valve core, a cover cap and a valve rod. An air inlet flow channel, an air outlet flow channel and a stepped groove are formed in the valve body, the stepped groove comprises a first cavity, a second cavity and a third cavity which are sequentially communicated, and a first stepped surface is arranged between the first cavity and the second cavity. The air inlet of the air inlet flow passage can be communicated with the air outlet flow passage through the first cavity. The valve core comprises a valve seat, a connecting piece and a diaphragm, the connecting piece is movably arranged in the stepped groove, the valve seat is arranged at the bottom of the connecting piece, and the diaphragm is fixedly sleeved on the connecting piece and always abuts against the first stepped surface. The cap is arranged in the third cavity in a sealing mode, the valve rod penetrates through the cap in a sealing mode and can move along the axial direction of the cap, the valve rod pushes the connecting piece to move towards the interior of the valve body, and the valve seat blocks the air inlet; or the connecting piece is pulled to move towards the outside of the valve body, and the valve seat opens the air inlet. The diaphragm valve can improve the pressure resistance and prolong the service life.

Description

Diaphragm valve

Technical Field

The invention relates to the technical field of diaphragms, in particular to a diaphragm valve.

Background

A commonly used vacuum diaphragm valve is a valve body that is used to shut off or connect a vacuum system by pressing a rubber diaphragm directly against a valve seat using a valve stem.

In the diaphragm valve, especially high pressure resistant diaphragm valve includes valve body, disk seat, diaphragm and valve rod, has inlet flow channel and outlet flow channel in the valve body, and the disk seat inlays to be fixed in the valve body and communicates with the air inlet of inlet flow channel. When the valve rod pushes the diaphragm to be plugged on the valve seat, the diaphragm and the valve seat form sealing and close the air inlet of the air inlet flow passage, so that the air inlet flow passage and the air outlet flow passage are isolated from each other. When the valve rod pushes the diaphragm to separate from the valve seat, the air inlet of the air inlet flow channel is opened, and the air inlet flow channel is communicated with the air outlet flow channel. In the long-term use process of the diaphragm valve, the valve seat is abraded due to frequent contact between the diaphragm and the valve seat, so that the sealing effect between the diaphragm and the valve seat is gradually weakened, the pressure resistance of the diaphragm valve is further influenced, and the service life of the diaphragm valve is shortened.

Therefore, a diaphragm valve is required to solve the above problems.

Disclosure of Invention

The invention aims to provide a diaphragm valve, which aims to improve the sealing effect and the pressure resistance of the diaphragm valve and prolong the service life of the diaphragm valve.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

a diaphragm valve, comprising:

the valve comprises a valve body, a valve body and a valve body, wherein an air inlet flow channel, an air outlet flow channel and a stepped groove are formed in the valve body, the stepped groove comprises a first cavity, a second cavity and a third cavity which are sequentially communicated, and a first stepped surface is arranged between the first cavity and the second cavity; the air inlet of the air inlet flow passage can be communicated with the air outlet flow passage through the first cavity, and the third cavity penetrates through the top end of the valve body;

the valve core comprises a valve seat, a connecting piece and a diaphragm, the connecting piece is movably arranged in the stepped groove, the valve seat is arranged at the bottom of the connecting piece, and the diaphragm is fixedly sleeved on the connecting piece and always abuts against the first stepped surface;

the cover cap is arranged in the third cavity in a sealing mode, the valve rod is arranged in the cover cap in a penetrating mode in a sealing mode and can move along the axial direction of the cover cap in a sealing mode, and the valve rod can push the connecting piece to move towards the interior of the valve body so that the valve seat blocks the air inlet; or the connecting piece is pulled to move towards the outside of the valve body, so that the valve seat opens the air inlet.

Preferably, the cap is provided with a guide hole, the valve rod is in threaded connection with the guide hole, and the bottom of the valve rod is provided with a first limit groove;

the valve core further comprises a valve head, the valve head is arranged in the cover cap in a sealing mode, the bottom of the valve head is fixedly connected with the connecting piece, the top of the valve head is clamped in the first limiting groove, and the valve rod can rotate around the axial direction of the valve rod relative to the valve head.

Preferably, the inner top wall of the first limiting groove is concave to form a second limiting groove, a ball is contained in the second limiting groove, and the ball protrudes out of the inner top wall of the first limiting groove;

spherical groove has been seted up to the top correspondence of valve head, works as the top of valve head with during first spacing groove joint cooperation, the ball rotationally set up in spherical groove.

Preferably, the connecting piece comprises a stop block and a connecting rod, the connecting rod is arranged at the upper end of the stop block, and the valve seat is arranged at the lower end of the stop block;

the bottom of the valve head is provided with a positioning hole, the connecting rod is in threaded connection with the positioning hole, and the valve head is abutted to the membrane.

Preferably, the number of the diaphragms is multiple, the diaphragms are sequentially stacked and sleeved on the connecting rod, and the diaphragms are welded with the connecting rod.

Preferably, the valve seat is annular, the stopper is correspondingly provided with an annular third limiting groove, and the valve seat is clamped in the third limiting groove and protrudes out of the bottom end of the stopper, so that the valve seat can block the air inlet.

Preferably, the inner bottom wall of the first cavity has a boss, the boss is provided with the air inlet, and the valve seat can be pressed against the boss and cover the air inlet.

Preferably, the diaphragm valve further includes:

the clamping ring is arranged in the second cavity, and the cap abuts against the upper end face of the clamping ring, so that the lower end face of the clamping ring abuts against the film.

Preferably, the lower end surface of the pressure ring extends downwards along the radial direction of the pressure ring from inside to outside in an inclined manner, so that the diaphragm deforms downwards along the radial direction of the pressure ring from inside to outside in an inclined manner; the first step surface is an inclined surface matched with the deformed membrane.

Preferably, the valve body further comprises:

the protective sheath, the valve body includes the main valve body and vice valve body, the one end of the main valve body has two along its radial outside extension vice valve body, two seted up respectively in the vice valve body the inlet channel with the runner of giving vent to anger, main valve is internal to be seted up along its axial extension the ladder groove, protective sheath cover is located the top of the main valve body.

The invention has the beneficial effects that:

according to the diaphragm valve provided by the invention, when the valve rod pushes the connecting piece to move towards the interior of the valve body, the valve seat and the connecting piece move synchronously, so that the valve seat is abutted against the inner wall of the first cavity, and the valve seat blocks the air inlet of the air inlet flow passage, so that the air inlet flow passage is disconnected with the air outlet flow passage. When the valve rod pushes the connecting piece to move towards the outside of the valve body, the valve seat and the connecting piece move synchronously, so that the valve seat is separated from the inner wall of the first cavity, the valve seat opens the air inlet of the air inlet channel, and the air inlet channel is communicated with the air outlet channel through the first cavity. Elastic deformation can take place for the diaphragm at the reciprocating motion in-process of connecting piece for the diaphragm can support all the time and press in first step face, thereby separates first cavity and second cavity, has guaranteed the inside sealed effect of valve body. The valve seat, the connecting piece and the diaphragm form a whole, so that the mutual abrasion between the diaphragm and the valve seat is avoided, the good sealing effect between the valve seat and the valve body and between the diaphragm and the valve body is ensured, the pressure resistance of the diaphragm valve is improved, and the service life of the diaphragm valve is prolonged.

Drawings

FIG. 1 is a cross-sectional view of a diaphragm valve provided by an embodiment of the present invention;

FIG. 2 is an enlarged view of a portion of FIG. 1 at A;

FIG. 3 is a cross-sectional view of a valve body provided by an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a valve head provided by an embodiment of the invention.

The component names and designations in the drawings are as follows:

1. a valve body; 11. a main valve body; 111. a first cavity; 1110. a boss; 112. a second cavity; 113. a third cavity; 110. a first step surface; 12. a sub-valve body; 121. an air inlet channel; 1210. an air inlet; 122. an air outlet flow channel; 13. a protective sleeve; 2. a valve seat; 3. a connecting member; 31. a stopper; 311. a third limiting groove; 32. a connecting rod; 4. a membrane; 5. a valve head; 51. a spherical groove; 52. positioning holes; 53. a head portion; 54. a sealing part; 55. a rod portion; 6. capping; 61. a guide hole; 7. a valve stem; 71. a first limit groove; 72. a second limit groove; 8. a ball bearing; 9. pressing a ring; 10. and (5) sealing rings.

Detailed Description

In order to make the technical problems solved, the technical solutions adopted and the technical effects achieved by the present invention clearer, the technical solutions of the present invention are further described below by way of specific embodiments with reference to the accompanying drawings. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some but not all of the elements associated with the present invention are shown in the drawings.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in a specific case to those of ordinary skill in the art.

In the present invention, unless expressly stated or limited otherwise, the recitation of a first feature "on" or "under" a second feature may include the recitation of the first and second features being in direct contact, and may also include the recitation that the first and second features are not in direct contact, but are in contact via another feature between them. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "right", etc. are used in an orientation or positional relationship based on that shown in the drawings only for convenience of description and simplicity of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.

The technical scheme of the invention is further explained by the specific implementation mode in combination with the attached drawings.

In the long-term use process of the existing high-pressure diaphragm valve, the valve seat is abraded due to frequent contact between the diaphragm and the valve seat, so that the sealing effect between the diaphragm and the valve seat is gradually weakened, the pressure resistance of the diaphragm valve is further influenced, and the service life of the diaphragm valve is shortened.

To solve the above problem, as shown in fig. 1 to 3, the present embodiment discloses a diaphragm valve, which may be a high-pressure diaphragm valve, having good pressure resistance.

Specifically, the diaphragm valve includes a valve body 1, a valve spool, a cap 6, and a valve stem 7. An inlet flow channel 121, an outlet flow channel 122 and a stepped groove are formed in the valve body 1, the stepped groove comprises a first cavity 111, a second cavity 112 and a third cavity 113 which are sequentially communicated, and a first stepped surface 110 is arranged between the first cavity 111 and the second cavity 112. The inlet 1210 of the inlet flow channel 121 can communicate with the outlet flow channel 122 through the first cavity 111, and the third cavity 113 penetrates through the top end of the valve body 1. The valve core comprises a valve seat 2, a connecting piece 3 and a diaphragm 4, the connecting piece 3 is movably arranged in the stepped groove, the valve seat 2 is arranged at the bottom of the connecting piece 3, and the diaphragm 4 is fixedly sleeved on the connecting piece 3 and always abuts against the first stepped surface 110. The cap 6 is installed in the third cavity 113 in a sealing mode, the valve rod 7 penetrates through the cap 6 in a sealing mode and can move along the axial direction of the cap 6, and the valve rod 7 can push the connecting piece 3 to move towards the inside of the valve body 1, so that the valve seat 2 blocks the air inlet 1210. Alternatively, the valve stem 7 pulls the connecting member 3 to move toward the outside of the valve body 1, so that the valve seat 2 opens the air inlet 1210.

In this embodiment, when the valve rod 7 pushes the connecting member 3 to move towards the inside of the valve body 1, the valve seat 2 and the connecting member 3 move synchronously, so that the valve seat 2 abuts against the inner wall of the first cavity 111, and the valve seat 2 blocks the air inlet 1210 of the inlet flow channel 121, so that the inlet flow channel 121 is disconnected from the outlet flow channel 122. When the valve rod 7 pushes the connecting piece 3 to move towards the outside of the valve body 1, the valve seat 2 and the connecting piece 3 move synchronously, so that the valve seat 2 is separated from contact with the inner wall of the first cavity 111, and the valve seat 2 opens the air inlet 1210 of the inlet flow channel 121, so that the inlet flow channel 121 is communicated with the outlet flow channel 122 through the first cavity 111. Elastic deformation can take place for diaphragm 4 in the reciprocating motion in-process of connecting piece 3 for diaphragm 4 supports all the time and presses in first step face 110, thereby separates first cavity 111 and second cavity 112, has guaranteed the inside sealed effect of valve body 1. The valve seat 2, the connecting piece 3 and the membrane 4 of this embodiment form a whole, avoid taking place wearing and tearing each other between membrane 4 and the valve seat 2, guaranteed to have good sealed effect between valve seat 2 and the valve body 1 and between membrane 4 and the valve body 1, improved the pressure resistance of diaphragm valve, prolonged the life of diaphragm valve simultaneously.

As shown in fig. 2 and 3, the valve body 1 includes a main valve body 11 and an auxiliary valve body 12, two auxiliary valve bodies 12 are extended from one end of the main valve body 11 along the radial direction, an inlet flow passage 121 and an outlet flow passage 122 are respectively disposed in the two auxiliary valve bodies 12, and a stepped groove extending along the axial direction is disposed in the main valve body 11. The first cavity 111, the second cavity 112, and the third cavity 113 are sequentially arranged from bottom to top along the axial direction of the main valve body 11, and the third cavity 113 penetrates through the top end of the main valve body 11, so that the valve core, the cap 6, and the valve rod 7 are conveniently mounted.

Specifically, as shown in fig. 1, the cap 6 has a U-shaped structure, and the outer periphery of the cap 6 is screwed to the inner wall of the third cavity 113. Meanwhile, the cap 6 is provided with a guide hole 61, and the valve rod 7 is in threaded connection with the guide hole 61. Can make in valve rod 7 can stretch out or stretch into block 6 along its axial through manual rotatory valve rod 7, when valve rod 7 stretched into block 6, can promote connecting piece 3 and move to valve body 1 inside, when valve rod 7 stretched out block 6, can pull connecting piece 3 and move to valve body 1 outside.

The screwing operation of the valve rod 7 of the present embodiment may be performed manually or by an actuator such as a pneumatic robot arm. As shown in fig. 1 and 3, the diaphragm valve further includes a protective sleeve 13, and the protective sleeve 13 is sleeved on the top end of the main valve body 11. Specifically, the top outer periphery of the main valve body 11 has an external thread, and when the valve stem 7 is screwed by hand, the protective sleeve 13 is screwed with the main valve body 11 to protect the integrity of the external thread of the main valve body 11. When it is desired that the actuator automatically screw the valve stem 7, the protective sleeve 13 is removed and the actuator is screwed to the main valve body 11.

As shown in fig. 1 and 4, the bottom of the valve rod 7 is provided with a first limit groove 71, the valve core further comprises a valve head 5, the valve head 5 is hermetically installed in the cap 6, the bottom of the valve head 5 is fixedly connected with the connecting piece 3, the top of the valve head 5 is clamped in the first limit groove 71, and the valve rod 7 can rotate around the axial direction of the valve head 5.

Specifically, the valve head 5 includes a head portion 53, a sealing portion 54 and a rod portion 55 which are connected in sequence, the head portion 53 is a columnar structure and has a conical head, the first limiting groove 71 is a T-shaped groove, and the head portion 53 of the valve head 5 is in clamping fit with the T-shaped groove. When the valve rod 7 is screwed, the valve head 5 can drive the connecting piece 3 to move along the axial direction of the valve rod 7, but the connecting piece cannot rotate along with the valve rod 7.

In the present embodiment, the cap 6 and the valve rod 7, the cap 6 and the main valve body 11, and the valve head 5 and the cap 6 are all mounted in a sealing manner, so as to improve the sealing performance of the diaphragm valve. As shown in fig. 1, the outer periphery of the cap 6, the inner ring of the guide hole 61, and the outer periphery of the sealing portion 54 of the valve head 5 are all provided with annular grooves, and a sealing ring 10 is disposed in each groove, so that the cap 6 can maintain good sealing with the main valve body 11, the valve rod 7, and the valve head 5.

In the embodiment, the inlet flow channel 121 and the outlet flow channel 122 are both communicated with the first cavity 111, the inner bottom wall of the first cavity 111 has a boss 1110, and the boss 1110 is provided with an inlet 1210 of the inlet flow channel 121. When the valve seat 2 is pressed against the boss 1110 and covers the inlet 1210, the inlet 1210 is blocked by the valve seat 2, and the inlet flow passage 121 is disconnected from the outlet flow passage 122. When the valve seat 2 is out of contact with the boss 1110, the inlet 1210 is opened and the inlet flow passage 121 remains in communication with the outlet flow passage 122.

As shown in fig. 1 and 4, the inner top wall of the first limiting groove 71 is concave to form a second limiting groove 72, the ball 8 is accommodated in the second limiting groove 72, and the ball 8 protrudes out of the inner top wall of the first limiting groove 71. The top of the valve head 5 is correspondingly provided with a spherical groove 51. When the top of the valve head 5 is snap-fitted into the first stopper groove 71, the ball 8 is rotatably disposed in the spherical groove 51. When screwing the valve rod 7 and stretching into the cap 6 and making the connecting piece 3 move towards the inside of the valve body 1, the valve head 5 can be twisted for 360 degrees along the horizontal direction in the first limiting groove 71, so as to finely adjust the installation angle of the valve head 5 and the connecting piece 3, improve the parallelism of the valve seat 2 and the boss 1110, and enhance the attaching degree of the valve seat 2 and the boss 1110 and the plugging effect of the air inlet 1210.

As shown in fig. 1 and 2, the connecting member 3 includes a stopper 31 and a link 32, the link 32 is provided at an upper end of the stopper 31, and the valve seat 2 is provided at a lower end of the stopper 31. The bottom of the valve head 5 is provided with a positioning hole 52, the connecting rod 32 is in threaded connection with the positioning hole 52, and the valve head 5 abuts against the diaphragm 4. Specifically, the rod part 55 of the valve head 5 is provided with a positioning hole 52, and the connecting rod 32 can extend into the positioning hole 52 and be in threaded connection with the positioning hole 52, so as to realize quick installation of the connector 3 and the valve head 5. When the valve seat 2 needs to be replaced after being used for a long time, the connecting piece 3 and the valve head 5 can be installed in a separable mode, and therefore the connecting piece 3 can be rapidly assembled, disassembled and replaced.

In addition, when the valve head 5 is in threaded connection with the connecting piece 3, the rod part 55 of the valve head 5 can press the membrane 4 against the stop block 31, so that the membrane 4 and the connecting rod 32 are prevented from being welded, and the connecting strength of the membrane 4 and the connecting piece 3 is further improved.

The number of the diaphragms 4 is multiple, the plurality of diaphragms 4 are sequentially overlapped and sleeved on the connecting rod 32, and the plurality of diaphragms 4 can improve the pressure resistance strength of the valve core. Meanwhile, the diaphragm 4 is welded with the connecting rod 32, so that the connection strength of the diaphragm 4 and the connecting piece 3 is improved, and good sealing between the diaphragm 4 and the connecting piece 3 can be ensured.

Specifically, the number of the diaphragms 4 of the present embodiment is four, and four diaphragms 4 are stacked together. The diaphragm 4 is provided with a central hole, the connecting rod 32 sequentially penetrates through the central holes of the four diaphragms 4, and the diaphragms 4 are abutted against the stop block 31 and are connected with the connecting rod 32 in a welding manner along the inner edge of the central hole. It will be appreciated that the specific number of diaphragms 4 may also be adapted according to design requirements.

As shown in fig. 1 and 2, the valve seat 2 is annular, the stopper 31 is correspondingly provided with an annular third limiting groove 311, and the valve seat 2 is clamped in the third limiting groove 311 and protrudes out of the bottom end of the stopper 31, so that the valve seat 2 can block the air inlet 1210. Specifically, the diaphragm 4 is welded on the connecting rod 32, and the valve seat 2 is clamped and fixed in the third limiting groove 311 of the stopper 31, so that the valve seat 2, the connecting piece 3 and the diaphragm 4 are connected into a whole, and the valve body 1 is matched for sealing, thereby improving the pressure resistance of the diaphragm valve.

It should be noted that, the diaphragm 4 has elasticity, and when the valve stem 7 drives the connecting piece 3 to move towards the inside or the outside of the valve body 1 through the valve head 5, the diaphragm 4 can elastically deform, so that the edge portion of the diaphragm 4 always abuts against the first step surface 110, thereby ensuring the sealing isolation between the first cavity 111 and the second cavity 112, and preventing external air or impurities from entering the inlet flow channel 121 or the outlet flow channel 122.

In order to ensure that the edge portion of the diaphragm 4 can always abut against the first step surface 110, as shown in fig. 1, the diaphragm valve further includes a pressing ring 9, the pressing ring 9 is disposed in the second cavity 112, and the cap 6 abuts against the upper end surface of the pressing ring 9, so that the lower end surface of the pressing ring 9 abuts against the diaphragm 4. After the diaphragm valve assembly is completed, the pressure ring 9 can be clamped in the first cavity 111, and the rod part 55 of the valve head 5 penetrates through the inner ring of the pressure ring 9 and is in threaded connection with the connecting rod 32 of the connecting piece 3, so that the valve body 1 is more compactly mounted, the rod part 55 of the valve head 5 is prevented from shaking greatly, and the moving stability of the connecting piece 3 is improved.

Preferably, as shown in fig. 2, the lower end surface of the pressing ring 9 extends obliquely downward from inside to outside in the radial direction thereof, so that the diaphragm 4 is deformed obliquely downward from inside to outside in the radial direction thereof. The first step surface 110 is an inclined surface adapted to the deformed diaphragm 4. Under the effect of the pressure force of the pressure ring 9, the outer edge part of the diaphragm 4 is curved in an arc shape, so that the edge of the diaphragm 4 is tightly attached to the first step surface 110, the sealing effect of the diaphragm 4 is enhanced, the first cavity 111 and the second cavity 112 are separated, and the good sealing effect in the first cavity 111 is ensured.

The foregoing embodiments are merely illustrative of the principles and features of this invention, which is not limited to the above-described embodiments, but rather is susceptible to various changes and modifications without departing from the spirit and scope of the invention, which changes and modifications are within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims

1. A diaphragm valve, comprising:

the valve comprises a valve body (1), wherein an air inlet flow channel (121), an air outlet flow channel (122) and a stepped groove are formed in the valve body, the stepped groove comprises a first cavity (111), a second cavity (112) and a third cavity (113) which are sequentially communicated, and a first stepped surface (110) is arranged between the first cavity (111) and the second cavity (112); the air inlet (1210) of the air inlet runner (121) can be communicated with the air outlet runner (122) through the first cavity (111), and the third cavity (113) penetrates through the top end of the valve body (1);

the valve core comprises a valve seat (2), a connecting piece (3) and a diaphragm (4), the connecting piece (3) is movably arranged in the stepped groove, the valve seat (2) is arranged at the bottom of the connecting piece (3), and the diaphragm (4) is fixedly sleeved on the connecting piece (3) and always abuts against the first stepped surface (110);

a cover cap (6) and a valve rod (7), wherein the cover cap (6) is installed in the third cavity (113) in a sealing mode, the valve rod (7) is arranged in the cover cap (6) in a sealing mode and can move axially, and the valve rod (7) is configured to push the connecting piece (3) to move towards the interior of the valve body, so that the valve seat (2) blocks the air inlet (1210); or pulling the connecting piece (3) to move towards the outside of the valve body so that the valve seat (2) opens the air inlet (1210).

2. The diaphragm valve of claim 1, wherein the cap (6) is provided with a guide hole (61), the valve rod (7) is in threaded connection with the guide hole (61), and the bottom of the valve rod (7) is provided with a first limit groove (71);

the valve core further comprises a valve head (5), the valve head (5) is installed in the cover cap (6) in a sealing mode, the bottom of the valve head (5) is fixedly connected with the connecting piece (3), the top of the valve head (5) is clamped in the first limiting groove (71), and the valve rod (7) can rotate around the axial direction of the valve head (5).

3. The diaphragm valve of claim 2, wherein the inner top wall of the first retainer groove (71) is recessed to form a second retainer groove (72), a ball (8) is accommodated in the second retainer groove (72), and the ball (8) protrudes out of the inner top wall of the first retainer groove (71);

spherical groove (51) have been seted up to the top correspondence of valve head (5), when the top of valve head (5) with first spacing groove (71) joint cooperation, ball (8) rotationally set up in spherical groove (51).

4. A diaphragm valve according to claim 2, wherein the connector (3) comprises a stop (31) and a link (32), the upper end of the stop (31) being provided with the link (32), the lower end of the stop (31) being provided with the valve seat (2);

the bottom of the valve head (5) is provided with a positioning hole (52), the connecting rod (32) is in threaded connection with the positioning hole (52), and the valve head (5) abuts against the diaphragm (4).

5. The diaphragm valve of claim 4, wherein the number of the diaphragms (4) is multiple, a plurality of the diaphragms (4) are sequentially stacked and sleeved on the connecting rod (32), and the diaphragms (4) are welded and connected with the connecting rod (32).

6. The diaphragm valve of claim 4, wherein the valve seat (2) is annular, the stopper (31) is correspondingly provided with an annular third limiting groove (311), and the valve seat (2) is clamped in the third limiting groove (311) and protrudes out of the bottom end of the stopper (31) so that the valve seat (2) can block the air inlet (1210).

7. The diaphragm valve of claim 6, wherein the inner bottom wall of the first cavity (111) is provided with a boss (1110), the boss (1110) is provided with the air inlet (1210), and the valve seat (2) can be pressed against the boss (1110) and is covered on the air inlet (1210).

8. The diaphragm valve of claim 1, further comprising:

clamping ring (10), set up in second cavity (112), cap (6) support press in the up end of clamping ring (10), so that the lower terminal surface of clamping ring (10) support press in on diaphragm (4).

9. The diaphragm valve of claim 8, wherein the lower end face of the pressure ring (10) extends obliquely downward from inside to outside in the radial direction thereof to deform the diaphragm (4) obliquely downward from inside to outside in the radial direction thereof; the first step surface (110) is an inclined surface adapted to the deformed diaphragm (4).

10. The diaphragm valve of claim 1 where the valve body further comprises:

protective sheath (9), valve body (1) is including the main valve body (11) and vice valve body (12), the one end of the main valve body (11) has two along its radial outside extension vice valve body (12), two seted up respectively in vice valve body (12) intake runner (121) with flow channel (122) of giving vent to anger, set up in the main valve body (11) along its axial extension the ladder groove, protective sheath (9) cover is located the top of the main valve body (11).