CN116146730B

CN116146730B - Pneumatic film regulating valve

Info

Publication number: CN116146730B
Application number: CN202310048776.XA
Authority: CN
Inventors: 李国军; 蔡水祥; 李益峰; 陈子达
Original assignee: Zhejiang Sansheng Instrument Co ltd
Current assignee: Zhejiang Sansheng Instrument Co ltd
Priority date: 2023-02-01
Filing date: 2023-02-01
Publication date: 2023-06-27
Anticipated expiration: 2043-02-01
Also published as: CN116146730A

Abstract

The invention belongs to the field of regulating valves, and particularly relates to a pneumatic film regulating valve which comprises a valve body, a leakage-proof cavity, a valve plug, a hole plug and a driving mechanism, wherein the leakage-proof cavity is arranged at a slot of the wall surface of a circular tubular valve body, and the valve plug which is used for opening and closing the valve body by sealing and matching with the slot is moved in the leakage-proof cavity along an inclined direction with an included angle smaller than 90 degrees with the center axis of the valve body. The weight arranged on the film A through the round rod A and the fluid sealed between the film A and the film B replace a spring structure in the existing regulating valve, and the small-mass weight generates larger acting force on the valve plug through the fluid sealed in the cone shell A and the cone shell B, so that the valve plug is easier to reset after high-pressure air or vacuum is eliminated, the accuracy of the opening of the valve body under specific air is ensured, and the accuracy of the invention on controlling the fluid flow is improved.

Description

Pneumatic film regulating valve

Technical Field

The invention belongs to the field of regulating valves, and particularly relates to a pneumatic film regulating valve.

Background

The pneumatic film regulating valve is called as regulating valve for short and consists of pneumatic executing mechanism and valve body. In many systems, the operating conditions, such as temperature, pressure, corrosion and contamination, experienced by the pneumatic diaphragm regulator valve are more severe than other components, so the pneumatic diaphragm regulator valve must have satisfactory operational stability and minimal maintenance when controlling the flow of process fluid.

In the use, the seal structure between the valve core and the valve seat and between the valve rod and the valve seat of the pneumatic film regulating valve is easy to leak, so that fluid leaks, and adverse effects are generated on the environment.

In addition, the air pressure for controlling the opening of the pneumatic film regulating valve can be changed along with the change of the fluid pressure, the deformation of the pneumatic film and the failure of the spring, so that the accuracy of the regulating valve on the fluid flow control is affected.

The invention designs a pneumatic film regulating valve to solve the problems.

Disclosure of Invention

In order to solve the defects in the prior art, the invention discloses a pneumatic film regulating valve which is realized by adopting the following technical scheme.

A pneumatic film regulating valve comprises a valve body, a leakage-proof cavity, a valve plug, a hole plug and a driving mechanism, wherein the leakage-proof cavity is arranged at a slot of the wall surface of a circular tubular valve body, and the valve plug which is in sealing fit with the slot to open and close the valve body is arranged in the leakage-proof cavity along an inclined direction with an included angle smaller than 90 degrees with the axis of the center of the valve body; the leakage-proof cavity is provided with a driving mechanism which drives the valve plug to accurately adjust the opening of the valve body in a pneumatic mode and replaces an easy-to-lose spring in the existing regulating valve by the gravity of which the weight with small mass is constantly multiplied to accurately drive the valve plug to completely open the valve body; the valve body is provided with an auxiliary hole communicated with the leakage-proof cavity on the wall surface positioned on one side of the slot low-pressure fluid, and the valve plug is provided with a hole plug for opening and closing the auxiliary hole from the outer side of the valve body.

As a further improvement of the technology, the valve plug is wedge-shaped which is inserted and assembled into the slot and provided with pressing inclined planes at two sides, and sealing rings matched with the corresponding side inclined planes on the valve plug are arranged on two end walls of the slot; the rubber pad that avoids the valve plug to form the striking to the valve body through the cooperation of valve plug lower extreme is installed to the arc surface of slot bottom, guarantees that the valve plug can form effective extrusion to two sealing washer of its both sides when inserting the slot and closing the valve body completely, and then reaches effective sealed purpose.

As a further improvement of the technology, both ends of the valve body are provided with flanges connected with the pipeline through bolts.

As a further improvement of the technology, the driving mechanism comprises a cone shell A, a cone shell B, a cylinder A, a cylinder B, a weight, a round rod A, a film B, a round rod B, a rack A, a gear B, a rotating shaft, a rack B and a slide bar, wherein the wall surface of the cone shell A fixedly connected with the leakage-proof cavity through two connecting rods is provided with an air charging port; a cone shell B is arranged on the cone shell A through a bolt, a film B is clamped between the cone shell A and the cone shell B in a sealing way, a film A is arranged in a cylinder A in the middle of the cone shell B in a sealing way, and a small-mass weight connected with the film A through a round rod A vertically slides in the cylinder B, the upper end of the cylinder A is communicated with the atmosphere; the space between the film A and the film B is filled with liquid; a round rod B connected with the film B is hermetically and slidably arranged in the round groove in the middle of the conical shell A; a rotating shaft is arranged between the two connecting rods, and a gear A and a gear B are arranged on the rotating shaft; the gear A is meshed with a rack A on the round rod B; the sliding rod arranged on the valve plug slides in the sliding groove at the upper end of the leakage-proof cavity in a sealing way, and the rack B fixedly connected with the sliding rod is meshed with the gear B.

As a further improvement of the technology, the driving mechanism comprises a cone shell A, a cone shell B, a cylinder A, a weight, a round rod A, a film B, a round rod B, a rack A, a gear B, a rotating shaft, a rack B and a sliding rod, wherein the cone shell B is fixedly connected with a leakage-proof cavity through two connecting rods, the film A is hermetically arranged in the cylinder A, which is communicated with the atmosphere, in the middle of the cone shell B, two small-mass weights vertically moving on the two connecting rods are connected with the film A through the round rod A, and a trapezoid guide block arranged on the weight slides in a trapezoid guide groove on the connecting rod; the conical shell A is arranged on the conical shell B through a bolt, and an extraction opening is formed in the wall surface of the conical shell A; a film B is clamped between the cone shell A and the cone shell B in a sealing way, and liquid is filled between the film B and the film A; a round rod B connected with the film B is hermetically and slidably arranged in the round groove in the middle of the conical shell A; a rotating shaft is arranged between the two connecting rods, and a gear A and a gear B are arranged on the rotating shaft; the gear A is meshed with a rack A connected with a round rod B through two synchronous rods; the sliding rod arranged on the valve plug slides in the sliding groove at the upper end of the leakage-proof cavity in a sealing way, and the rack B fixedly connected with the sliding rod is meshed with the gear B.

As a further improvement of the technology, the transmission ratio of the gear A to the rack B is larger than 1, and the purpose of enabling the valve plug to rapidly and effectively switch the valve body can be achieved when the valve plug, the film A and the film B generate small movement deformation.

As a further improvement of the technology, a sealing structure A is matched between the round rod B and the round groove in the middle of the conical shell A, and a sealing structure B is matched between the sliding rod and the sliding groove on the leakage-proof cavity.

Compared with the traditional pneumatic film regulating valve, the compression inclined plane on the valve plug can squeeze the sealing ring on the high-pressure fluid side of the inserting groove to form good sealing when the valve plug closes the valve body, liquid can be filled in the leakage-proof cavity in the closing process of the valve plug, and when the sealing ring on the high-pressure fluid side of the inserting groove leaks due to corrosion, the liquid on the high-pressure fluid side of the valve body can be effectively prevented from entering the leakage-proof cavity to leak, and the liquid in the leakage-proof cavity is discharged through the auxiliary hole after the valve plug is opened next time and is replaced after the valve plug is closed again, so that the deterioration of the liquid stored in the leakage-proof cavity is avoided.

The weight arranged on the film A through the round rod A and the fluid sealed between the film A and the film B replace a spring structure in the existing regulating valve, and the small-mass weight generates larger acting force on the valve plug through the fluid sealed in the cone shell A and the cone shell B, so that the valve plug is easier to reset after high-pressure air or vacuum is eliminated, the valve plug can be completely reset and opened after the high-pressure air or vacuum is eliminated without considering whether the spring is invalid after long-time use, and the air pressure value generated by the high-pressure air or the negative pressure value generated by the vacuum is always matched with the opening of the valve plug on the valve body in a one-to-one correspondence manner without change, thereby ensuring the accuracy of the opening of the valve body under specific air pressure and improving the accuracy of the fluid flow control.

The invention has simple structure and better use effect.

Drawings

Fig. 1 is a schematic cross-sectional view of a first embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of a valve plug, a bore plug, and a valve body mated.

Fig. 3 is a schematic diagram of the drive connection of the rack a and the rack B.

Fig. 4 is a schematic cross-sectional view of the inner structure of the conical shell a and the conical shell B according to the first embodiment of the present invention.

Fig. 5 is a schematic cross-sectional view of a second embodiment of the present invention.

Fig. 6 is a schematic diagram of a driving connection between a rack a and a rack B in a second embodiment of the present invention.

Fig. 7 is a schematic cross-sectional view of the inner structure of the conical shell a and the conical shell B in the second embodiment of the present invention.

FIG. 8 is a schematic cross-sectional view of the valve body mated with the leak-proof chamber.

Reference numerals in the figures: 1. a valve body; 2. a flange; 3. a slot; 4. a T-shaped groove; 5. an auxiliary hole; 6. a leak-proof cavity; 7. a chute; 8. a connecting rod; 9. a trapezoidal guide groove; 10. a cone shell A; 11. an inflation inlet; 12. a bolt; 13. a cone shell B; 14. a cylinder A; 15. a cylinder B; 16. a round hole; 17. a weight block; 18. round bar A; 19. a ring plate A; 20. a nut A; 21. a film A; 22. a film B; 23. a round rod B; 24. a ring plate B; 25. a nut B; 26. a sealing structure A; 27. a rack A; 28. a gear A; 29. a gear B; 30. a rotating shaft; 31. a rack B; 32. a slide bar; 33. a sealing structure B; 34. a valve plug; 35. compacting the inclined plane; 36. a seal ring; 37. a T-ring; 38. a rubber pad; 39. a mounting sleeve; 40. a hole plug; 41. a driving mechanism; 42. an extraction opening; 43. a synchronizing lever; 44. a trapezoidal guide block.

Description of the embodiments

The drawings are schematic representations of the practice of the invention to facilitate understanding of the principles of operation of the structure. The specific product structure and the proportional size are determined according to the use environment and the conventional technology.

As shown in fig. 1 and 5, the valve comprises a valve body 1, a leakage preventing cavity 6, a valve plug 34, a hole plug 40 and a driving mechanism 41, wherein as shown in fig. 2 and 8, the leakage preventing cavity 6 is arranged at a slot 3 of the wall surface of the circular tubular valve body 1, and the valve plug 34 which is used for switching the valve body 1 through sealing fit with the slot 3 is moved in the leakage preventing cavity 6 along an inclined direction with an included angle smaller than 90 degrees with the center axis of the valve body 1; as shown in fig. 1 and 5, a driving mechanism 41 which drives the valve plug 34 in a pneumatic manner to accurately adjust the opening of the valve body 1 and replaces a failure-prone spring in the existing regulating valve by the gravity which is constantly multiplied by the small-mass weight 17 to accurately drive the valve plug 34 to completely open the valve body 1 is arranged on the leakage-proof cavity 6; as shown in fig. 2 and 8, the valve body 1 has an auxiliary hole 5 communicating with the leakage preventing chamber 6 on a wall surface of the insertion groove 3 on the low pressure fluid side, and the valve plug 34 is provided with a plug 40 for opening and closing the auxiliary hole 5 from the outside of the valve body 1.

As shown in fig. 1, 2 and 5, the valve plug 34 is wedge-shaped, which is inserted into the slot 3, and has pressing inclined planes 35 at two sides, and sealing rings 36 matched with corresponding side inclined planes on the valve plug 34 are installed on two end walls of the slot 3; the rubber pad 38 which can prevent the valve plug 34 from impacting the valve body 1 by being matched with the lower end of the valve plug 34 is arranged on the circular arc surface at the bottom of the slot 3, so that the valve plug 34 can effectively extrude two sealing rings 36 on two sides of the valve body 1 when the valve plug 34 is inserted into the slot 3 to be completely closed, and the purpose of effective sealing is achieved.

As shown in fig. 8, both ends of the valve body 1 are provided with flanges 2 connected to a pipeline by bolts 12.

As shown in fig. 1, 3 and 4, the driving mechanism 41 includes a cone shell a10, a cone shell B13, a cylinder a14, a cylinder B15, a weight 17, a round rod a18, a thin film a21, a thin film B22, a round rod B23, a rack a27, a gear a28, a gear B29, a rotating shaft 30, a rack B31 and a sliding rod 32, wherein an air charging port 11 is formed on the wall surface of the cone shell a10 fixedly connected with the leakage-proof cavity 6 through two connecting rods 8; a cone shell B13 is arranged on the cone shell A10 through a bolt 12, a film B22 is clamped between the cone shell A10 and the cone shell B13 in a sealing way, a film A21 is arranged in a cylinder A14 in the middle of the cone shell B13 in a sealing way, and a small-mass weight 17 connected with the film A21 through a round rod A18 is vertically slid in a cylinder B15, the upper end of the cylinder A14 is communicated with the atmosphere; the space between the film A21 and the film B22 is filled with liquid; a round rod B23 connected with the film B22 is hermetically and slidably arranged in the round groove in the middle of the cone shell A10; a rotating shaft 30 is arranged between the two connecting rods 8, and a gear A28 and a gear B29 are arranged on the rotating shaft 30; the gear A28 is meshed with a rack A27 on the round rod B23; the sliding rod 32 arranged on the valve plug 34 is hermetically slid in the sliding groove 7 at the upper end of the leakage-proof cavity 6, and the rack B31 fixedly connected with the sliding rod 32 is meshed with the gear B29.

As shown in fig. 5, 6 and 7, the driving mechanism 41 includes a cone shell a10, a cone shell B13, a cylinder a14, a weight 17, a round bar a18, a film a21, a film B22, a round bar B23, a rack a27, a gear a28, a gear B29, a rotating shaft 30, a rack B31 and a slide bar 32, wherein the cone shell B13 is fixedly connected with the leakage-proof cavity 6 through two connecting rods 8, the film a21 is hermetically installed in the cylinder a14 which is communicated with the atmosphere in the middle of the cone shell B13, two small-mass weights 17 vertically moving on the two connecting rods 8 are connected with the film a21 through the round bar a18, and a trapezoidal guide block 44 installed on the weight 17 slides in a trapezoidal guide groove 9 on the connecting rod 8; the conical shell A10 is arranged on the conical shell B13 through a bolt 12, and an extraction opening 42 is formed in the wall surface of the conical shell A10; a film B22 is clamped between the cone shell A10 and the cone shell B13 in a sealing way, and liquid is filled between the film B22 and the film A21; a round rod B23 connected with the film B22 is hermetically and slidably arranged in the round groove in the middle of the cone shell A10; a rotating shaft 30 is arranged between the two connecting rods 8, and a gear A28 and a gear B29 are arranged on the rotating shaft 30; the gear A28 is meshed with a rack A27 connected with a round rod B23 through two synchronous rods 43; the sliding rod 32 arranged on the valve plug 34 is hermetically slid in the sliding groove 7 at the upper end of the leakage-proof cavity 6, and the rack B31 fixedly connected with the sliding rod 32 is meshed with the gear B29.

As shown in fig. 3 and 6, the transmission ratio of the gear a28 to the rack B31 is greater than 1, so that the valve plug 34 can be opened and closed quickly and effectively to the valve body 1 when the valve plug 34, the film a21 and the film B22 are deformed in a small movement.

As shown in fig. 1, 4 and 7, a sealing structure a26 is matched between the round rod B23 and the round groove in the middle of the conical shell a10, and a sealing structure B33 is matched between the sliding rod 32 and the sliding groove 7 on the leakage-proof cavity 6.

As shown in fig. 2 and 8, the sealing ring 36 is fixed to the end wall of the slot 3 by the engagement of a T-ring 37 thereon with a T-groove 4 on the end wall of the slot 3.

As shown in fig. 1, the top and side walls of the cylinder B15 are provided with circular holes 16 communicating with the atmosphere, ensuring that the movement of the weight 17 is not affected.

As shown in fig. 4 and 7, the round rod a18 is in threaded fit with a nut a20 for sealing and pressing the film a21 against the annular plate a19 on the round rod a 18; the circular plate B is screwed with a nut B25 for sealing and pressing the film B22 against the annular plate B24 on the circular rod B23.

As shown in fig. 2, the plug 40 is mounted within a mounting sleeve 39 that is fixedly attached to the plug 34, ensuring that the plug 40 can be replaced.

The working flow of the invention is as follows: in the initial state, the weight 17 in the first embodiment is located at the lowest end of the movement amplitude, the film a21 and the film B22 are concave, the valve plug 34 is in a completely opened state to the valve body 1, and the hole plug 40 is in an opened state to the auxiliary hole 5. The weight 17 in the second embodiment is located at the lowest end of the movement amplitude, the film a21 and the film B22 are concave, the valve plug 34 is in a completely opened state to the valve body 1, and the hole plug 40 is in an opened state to the auxiliary hole 5.

When it is necessary to control the flow rate of the high-pressure fluid flowing through the valve body 1, it is necessary to adjust the opening degree of the valve body 1 by adjusting the valve plug 34.

The operation flow of the first scheme is as follows: the high-pressure air is filled into the space between the film B22 and the wall of the cone shell A10 through the air filling opening 11 on the cone shell A10, and the inlet amount of the high-pressure air is matched with the opening of the valve plug 34 to the valve body 1.

When high-pressure air enters a space between the film B22 and the shell wall of the cone shell A10, the upper top of the high-pressure air which is entered by the film B22 is convexly changed, the film B22 pushes the film A21 to convexly deform through liquid which is stored between the film B22 and the film A21, and the film A21 drives the counterweight to vertically move upwards in the cylinder B15 by a certain amplitude through the round rod A18.

Meanwhile, the film B22 drives the rack A27 to move upwards through the round rod B23, and the rack A27 drives the valve plug 34 to move in the slot 3 in a certain amplitude in a rapid oblique way through the gear A28, the rotating shaft 30, the gear B29, the rack B31 and the sliding rod 32, so that the opening of the valve body 1 is adjusted.

If the valve body 1 needs to be completely closed, high-pressure air is continuously filled into the conical shell A10 through the air filling opening 11, so that the deformation of the film B22 and the deformation of the film A21 are continuously increased, and the valve plug 34 is completely inserted into the slot 3 on the inner wall of the valve body 1 and is completely closed on the valve body 1. After the valve plug 34 completely closes the valve body 1, the two pressing inclined planes 35 at two sides of the valve plug 34 respectively squeeze the corresponding side sealing rings 36, so that the tightness of the valve body 1 in the closed state is ensured.

In the process that the valve plug 34 is completely closed to the valve body 1, the valve body 1 can drive the hole plug 40 to close the auxiliary hole 5, fluid can be accumulated in the leakage-proof cavity 6, the fluid accumulated in the leakage-proof cavity 6 can effectively prevent the fluid on one side of the high-pressure fluid in the valve body 1 from leaking due to corrosion failure of the corresponding side sealing ring 36, meanwhile, the resistance of the valve plug 34, which is almost perpendicular to the movement direction of the fluid, to the fluid is minimum in the process that the valve plug 34 closes the valve body 1, and the accuracy of opening adjustment of the valve body 1 is further improved.

When the valve body 1 needs to be fully opened, the high-pressure gas is stopped from being filled into the conical shell A10, the conical shell A10 is communicated with the outside through the charging port 11, and the air pressure in the conical shell A10 is reduced to the atmospheric pressure. The weight 17 drives the round rod B23 to vertically move downwards through the round rod a18, the membrane a21, the liquid stored between the membrane a21 and the membrane B22, and the round rod B23 drives the valve plug 34 to be separated from the slot 3 through a series of transmission and is completely opened for the valve body 1. Simultaneously, the valve plug 34 drives the hole plug 40 to open the auxiliary hole 5, and the fluid stored in the leakage-proof cavity 6 is discharged through the opened auxiliary hole 5, so that the fluid stored in the leakage-proof cavity 6 is prevented from deteriorating.

The operation flow of the first scheme is as follows: air is pumped out from the space between the film B22 and the shell wall of the cone shell A10 through the pumping hole 42 on the cone shell A10, so that negative pressure is generated in the space between the film B22 and the shell wall of the cone shell A10, and the generated negative pressure is matched with the opening degree of the valve plug 34 to the valve body 1.

When negative pressure is generated between the film B22 and the shell wall of the cone shell A10, the film B22 is convexly deformed upwards under the action of the negative pressure, the film B22 pulls the film A21 to convexly deform through liquid stored between the film B22 and the film A21, and the film A21 drives two small-mass counterweights to vertically move upwards by a certain amplitude through the round rod A18.

Meanwhile, the film B22 drives the rack A27 to move upwards through the round rod B23 and the two synchronous rods 43, and the rack A27 drives the valve plug 34 to move in the slot 3 in a certain amplitude in a rapid oblique way through the gear A28, the rotating shaft 30, the gear B29, the rack B31 and the sliding rod 32, so that the opening degree of the valve body 1 is adjusted.

If the valve body 1 needs to be completely closed, the air is continuously pumped out of the conical shell A10 through the air pumping hole 42 so that larger negative pressure is generated in the conical shell A10, the upward convex variables of the film B22 and the film A21 are continuously increased, and therefore the valve plug 34 is completely inserted into the slot 3 of the inner wall of the valve body 1 and the valve body 1 is completely closed. After the valve plug 34 completely closes the valve body 1, the two pressing inclined planes 35 at two sides of the valve plug 34 respectively squeeze the corresponding side sealing rings 36, so that the tightness of the valve body 1 in the closed state is ensured.

When the valve body 1 needs to be fully opened, the air suction from the inside of the cone shell a10 is stopped and the cone shell a10 is communicated with the outside through the air suction opening 42, so that the air pressure in the cone shell a10 is instantaneously increased to the atmospheric pressure. The two small-mass weights 17 drive the round rod B23 to vertically move downwards through the round rod A18, the membrane A21, the liquid stored between the membrane A21 and the membrane B22, and the round rod B23 drives the valve plug 34 to be separated from the slot 3 through a series of transmission and is completely opened for the valve body 1. Simultaneously, the valve plug 34 drives the hole plug 40 to open the auxiliary hole 5, and the fluid stored in the leakage-proof cavity 6 is discharged through the opened auxiliary hole 5, so that the fluid stored in the leakage-proof cavity 6 is prevented from deteriorating.

In either the first or the second scheme, the small-mass weight 17, the film a21 and the liquid and film B22 sealed between the film a21 and the film B22 replace the spring in the traditional regulating valve, and the volume of the liquid between the film a21 and the film B22 is not changed and the mass of the middle weight 17 is constant, so that the structure formed by the small-mass weight 17, the film a21, the liquid sealed between the film a21 and the film B22 for resetting the valve body 1 has high stability, the problem of failure caused by long-time use does not exist, and compared with the failure problem of the traditional spring resetting, the transmission structure formed by the small-mass weight 17, the film a21, the liquid sealed between the film a21 and the film B22 can improve the control precision of the opening degree regulation of the valve body 1, the high pressure or the negative pressure cannot be matched and regulated again after the film a21, the film B22 and the spring are deformed, and the service life and the opening degree regulation efficiency of the regulating valve are improved.

In summary, the beneficial effects of the invention are as follows: according to the invention, the pressing inclined surface 35 on the valve plug 34 can squeeze the sealing ring 36 on the high-pressure fluid side of the insertion groove 3 to form good sealing when the valve plug 34 closes the valve body 1, in the closing process of the valve plug 34, the leakage preventing cavity 6 can be filled with liquid, and when the sealing ring 36 on the high-pressure fluid side of the insertion groove 3 leaks due to corrosion, the liquid on the high-pressure fluid side of the valve body 1 can be effectively prevented from entering the leakage preventing cavity 6 to leak, and the liquid in the leakage preventing cavity 6 is discharged through the auxiliary hole 5 after the valve plug 34 is opened next time and is replaced after the valve plug 34 is closed again, so that the deterioration of the liquid stored in the leakage preventing cavity 6 is avoided.

According to the invention, the weight 17 arranged on the film A21 through the round rod A18 and the fluid sealed between the film A21 and the film B22 replace the spring structure in the existing regulating valve, the small-mass weight 17 generates larger acting force on the valve plug 34 through the fluid sealed in the cone shell A10 and the cone shell B13, so that the valve plug 34 is easier to reset after high-pressure air or vacuum is eliminated, the valve plug 34 can be completely reset and opened after the high-pressure air or vacuum is eliminated without considering whether the spring is invalid after long-time use, and the air pressure value generated by the high-pressure air or the negative pressure value generated by vacuum is always matched with the opening of the valve plug 34 on the valve body 1 one by one without change, thereby ensuring the accuracy of the opening of the valve body 1 under specific air pressure, and improving the accuracy of the fluid flow control.

Claims

1. A pneumatic membrane regulating valve, characterized in that: the valve comprises a valve body, a leakage-proof cavity, a valve plug, a hole plug and a driving mechanism, wherein the leakage-proof cavity is arranged at a slot of the wall surface of the circular tubular valve body, and the valve plug which is in sealing fit with the slot to open and close the valve body is arranged in the leakage-proof cavity along an inclined direction with an included angle smaller than 90 degrees with the axis of the center of the valve body; the leakage-proof cavity is provided with a driving mechanism which drives the valve plug to accurately adjust the opening of the valve body in a pneumatic mode and replaces an easy-to-lose spring in the existing regulating valve by the gravity of which the weight with small mass is constantly multiplied to accurately drive the valve plug to completely open the valve body; an auxiliary hole communicated with the leakage-proof cavity is formed in the wall surface of the valve body, which is positioned on one side of the slot low-pressure fluid, and a hole plug for opening and closing the auxiliary hole from the outer side of the valve body is arranged on the valve plug;

the valve plug is wedge-shaped which is inserted into the slot and is assembled with a pressing inclined plane at two sides, and sealing rings matched with corresponding side inclined planes on the valve plug are arranged on two end walls of the slot; a rubber pad which is matched with the lower end of the valve plug to prevent the valve plug from impacting the valve body is arranged on the arc surface at the bottom of the slot;

the driving mechanism comprises a cone shell A, a cone shell B, a cylinder A, a cylinder B, a weight, a round rod A, a film B, a round rod B, a rack A, a gear B, a rotating shaft, a rack B and a sliding rod, wherein an inflation inlet is formed in the wall surface of the cone shell A fixedly connected with the leakage-proof cavity through two connecting rods; a cone shell B is arranged on the cone shell A through a bolt, a film B is clamped between the cone shell A and the cone shell B in a sealing way, a film A is arranged in a cylinder A in the middle of the cone shell B in a sealing way, and a small-mass weight connected with the film A through a round rod A vertically slides in the cylinder B, the upper end of the cylinder A is communicated with the atmosphere; the space between the film A and the film B is filled with liquid; a round rod B connected with the film B is hermetically and slidably arranged in the round groove in the middle of the conical shell A; a rotating shaft is arranged between the two connecting rods, and a gear A and a gear B are arranged on the rotating shaft; the gear A is meshed with a rack A on the round rod B; a sliding rod arranged on the valve plug slides in a sliding groove at the upper end of the leakage-proof cavity in a sealing way, and a rack B fixedly connected with the sliding rod is meshed with the gear B;

or the driving mechanism comprises a cone shell A, a cone shell B, a cylinder A, a weight, a round rod A, a film B, a round rod B, a rack A, a gear B, a rotating shaft, a rack B and a sliding rod, wherein the cone shell B is fixedly connected with a leakage-proof cavity through two connecting rods, the film A is hermetically arranged in the cylinder A, which is communicated with the atmosphere, in the middle of the cone shell B, two small-mass weights vertically moving on the two connecting rods are connected with the film A through the round rod A, and a trapezoid guide block arranged on the weight slides in a trapezoid guide groove on the connecting rod; the conical shell A is arranged on the conical shell B through a bolt, and an extraction opening is formed in the wall surface of the conical shell A; a film B is clamped between the cone shell A and the cone shell B in a sealing way, and liquid is filled between the film B and the film A; a round rod B connected with the film B is hermetically and slidably arranged in the round groove in the middle of the conical shell A; a rotating shaft is arranged between the two connecting rods, and a gear A and a gear B are arranged on the rotating shaft; the gear A is meshed with a rack A connected with a round rod B through two synchronous rods; the sliding rod arranged on the valve plug slides in the sliding groove at the upper end of the leakage-proof cavity in a sealing way, and the rack B fixedly connected with the sliding rod is meshed with the gear B.

2. A pneumatic diaphragm regulator valve according to claim 1, wherein: the two ends of the valve body are provided with flanges connected with the pipeline through bolts.

3. A pneumatic diaphragm regulator valve according to claim 1, wherein: the transmission ratio of the gear A to the rack B is greater than 1.

4. A pneumatic diaphragm regulator valve according to claim 1, wherein: a sealing structure A is matched between the round rod B and the round groove in the middle of the conical shell A, and a sealing structure B is matched between the sliding rod and the sliding groove on the leakage-proof cavity.