CN210830490U

CN210830490U - Speed control valve

Info

Publication number: CN210830490U
Application number: CN201921456213.XU
Authority: CN
Inventors: 林南翔
Original assignee: Wenzhou Jinye Pneumatic Technology Co ltd
Current assignee: Wenzhou Jinye Pneumatic Technology Co ltd
Priority date: 2019-09-03
Filing date: 2019-09-03
Publication date: 2020-06-23
Anticipated expiration: 2029-09-03

Abstract

The utility model discloses a speed control valve, which relates to the technical field of valves, and the key points of the technical proposal of the speed control valve comprise an air inlet valve body, an air outlet valve body and an adjusting valve body, wherein the air inlet valve body is connected with the adjusting valve body, the adjusting valve body is connected with the air outlet valve body, the adjusting valve body is provided with a movable hole and a fixed hole, the adjusting valve body is fixedly connected with an insertion pipe, one end of the insertion pipe is provided with a second air inlet hole, an adjusting component for adjusting the flow of fluid is arranged in the fixed hole, the adjusting component comprises a fixed shaft arranged in the fixed hole, and the fixed shaft is detachably connected; the outer surface of the regulating valve body is provided with a tapered hole communicated with the fixing hole, and the regulating valve body is externally provided with an operation ring groove; the locking assembly comprises a ball, a fixing ring and a clamp spring, a limiting spring and a locking pipe are sleeved outside the adjusting valve body, and a locking ring groove for the ball to be embedded in is formed in the fixing shaft; the utility model discloses have the convenience and change or maintain adjusting part's part with adjusting part and adjusting valve body's separation.

Description

Speed control valve

Technical Field

The utility model relates to a technical field of valve, more specifically say that it relates to a speed control valve.

Background

The speed control valve plays an indispensable role in the whole production system of pneumatic element products, and the flow rate and the speed of media such as air and fluid entering and exiting the exhaust hole are controlled and operated by the speed control valve.

At present, the regulating mechanism and the valve body which are used for regulating the flowing speed of fluid on the existing speed control valve are generally clamped, when the internal parts of the regulating mechanism need to be replaced, the clamping position is easily damaged, and when the regulating mechanism is reconnected with the valve body, the sealing performance of the speed control valve is greatly reduced, so that the speed control valve which is convenient to disassemble is needed.

SUMMERY OF THE UTILITY MODEL

The utility model provides a speed control valve, have the separation of convenient with adjusting part and adjusting valve body, change or maintain adjusting part's part to prior art exists not enough.

In order to achieve the above purpose, the utility model provides a following technical scheme: a speed control valve comprises an air inlet valve body, an air outlet valve body and an adjusting valve body, wherein the air inlet valve body is connected with the adjusting valve body, the adjusting valve body is connected with the air outlet valve body, a movable hole is formed in the upper end of the adjusting valve body, a fixed hole communicated with the movable hole is formed in the right end of the adjusting valve body, an insertion pipe is fixedly connected to the outer surface of the adjusting valve body, a second air inlet hole communicated with the fixed hole is formed in one end, away from the fixed hole, of the insertion pipe, an adjusting assembly for adjusting the flow of fluid is arranged in the fixed hole, the adjusting assembly comprises a fixed shaft arranged in the fixed hole, and the fixed shaft is detachably connected with; the outer surface of the adjusting valve body is provided with a tapered hole communicated with the fixing hole, the inner diameter of the tapered hole is sequentially reduced from one end far away from the axis of the fixing hole to one end close to the axis of the fixing hole, and the adjusting valve body is externally provided with an operation ring groove; the locking assembly comprises a ball arranged in the tapered hole, a fixing ring fixedly connected to the outer surface of the adjusting valve body and a clamp spring arranged in the operation ring groove, a limiting spring and a locking pipe are sleeved outside the adjusting valve body and positioned between the fixing ring and the clamp spring, two ends of the limiting spring are respectively abutted against the fixing ring and the locking pipe, and the fixing shaft is provided with a locking ring groove for the ball to be embedded in; when one end of the locking pipe, which is far away from the fixing ring, is abutted against the clamp spring, the inner surface of the locking pipe is abutted against the outer surfaces of the ball bearing and the adjusting valve body respectively; when the regulating valve body is connected with the fixed shaft, the ball is embedded into the locking ring groove.

By adopting the technical scheme, the fluid enters the air inlet valve body, passes through the adjusting valve body and is discharged from the air outlet valve body, so that the fluid is conveyed from one end of the speed control valve to the other end of the speed control valve; the flow of the fluid entering the regulating valve body is regulated through the regulating assembly, so that the flow of the fluid entering the gas outlet valve body is controlled, and the effect of regulating the flow speed of the fluid is achieved; when the adjusting assembly is disassembled, the locking tube moves towards the fixing ring, so that the adjusting assembly is pulled out from the fixing hole, the adjusting assembly is separated from the adjusting valve body, and the adjusting assembly is convenient for workers to replace or maintain parts of the adjusting assembly.

The utility model discloses further set up to: the taper hole is provided with a plurality of and sets up along adjusting valve body circumference array.

Through adopting above-mentioned technical scheme, through a plurality of bell mouths and set up the ball in the bell mouth for the fixed axle is more stable with being connected of adjusting valve body.

The utility model discloses further set up to: and a chamfer is formed at the joint of one end of the fixed shaft facing the movable hole and the outer circumferential surface of the fixed shaft.

Through adopting above-mentioned technical scheme, conveniently insert the fixed axle in the fixed orifices.

The utility model discloses further set up to: the one end fixedly connected with holding ring that the activity hole was kept away from to the fixed axle, works as when ball embedding locking ring groove, the holding ring butt regulating valve body.

Through adopting above-mentioned technical scheme, when the holding ring with adjust the valve body butt, can prevent that the fixed axle from continuing to move towards the activity hole.

The utility model discloses further set up to: the adjusting part further comprises a fixed rod fixedly connected to one end, close to the movable hole, of the fixed shaft, an operation hole penetrating through the fixed rod is formed in one end, far away from the movable hole, of the fixed shaft, a third air inlet hole communicated with the operation hole is formed in the outer surface of the fixed rod, and an operation rod is detachably connected to the operation hole.

Through adopting above-mentioned technical scheme, the action bars removes for the dead lever for fixed orifices, third air inlet and operation hole intercommunication, and the flow of regulation fluid

The utility model discloses further set up to: and one end of the operating rod, which is far away from the movable hole, is fixedly connected with a hand wheel.

Through adopting above-mentioned technical scheme, can conveniently drive the action bars through the hand wheel and rotate.

The utility model discloses further set up to: the air inlet valve body is provided with a first air inlet hole, one end of the air inlet valve body, facing the adjusting valve body, is provided with a first air outlet hole communicated with the first air inlet hole, and the insertion pipe is inserted into the first air outlet hole.

Through adopting above-mentioned technical scheme, through inserting the intubate in first outlet port, the intake valve body is connected with the adjusting valve body.

The utility model discloses further set up to: the gas outlet valve body penetrates through the movable hole, a closed groove is formed in the bottom of the gas outlet valve body, a driving groove is formed in the upper end of the gas outlet valve body, a through hole communicated with the driving groove is formed in one end, far away from the opening, of the closed groove, the closed groove is provided with a sealing assembly for sealing the through hole, and a driving assembly for driving the sealing assembly to move is arranged in the driving groove.

By adopting the technical scheme, the through hole can be sealed by the sealing component, so that the fluid is prevented from flowing out of the air outlet valve body; the driving assembly can drive the closing assembly to move, the through hole can be opened, and the fluid hole is conveyed from one end of the speed control valve to the other end of the speed control valve.

The utility model discloses further set up to: the outer surface of the air outlet valve body is provided with a fourth air inlet hole communicated with the through hole, the sealing assembly comprises a sealing disc and a sealing block, the sealing disc and the sealing block are arranged in a sealing groove, a guide groove is formed in the bottom of the sealing block, a guide hole communicated with the sealing groove is formed in the outer surface of the sealing block, the sealing disc is abutted to the sealing groove and is far away from the end face of the opening, a sealing rod penetrating the sealing block is fixedly connected to the bottom of the sealing disc, a sealing spring is sleeved outside the sealing rod, and two ends of the sealing spring are respectively abutted to the sealing disc and.

By adopting the technical scheme, the sealing disc seals the through hole through the acting force of the sealing spring; in addition, after the driving assembly drives the closed disk surface to descend, the through hole, the closed groove, the guide hole and the guide groove are communicated, the sealing spring is compressed, and when the driving assembly mechanism does not drive the closed disk, the sealing spring resets to drive the closed disk to re-seal the through hole.

The utility model discloses further set up to: the outer surface of the gas outlet valve body is provided with a ventilation hole communicated with the driving groove, the driving assembly comprises a driving cover arranged in the driving groove and a piston disc abutted against the bottom of the driving cover, the driving cover seals the driving groove, the upper end of the driving cover is provided with a gas filling hole communicated with the driving groove, the outer diameter of the piston disc is the same as the inner diameter of the driving groove, the bottom of the piston disc is fixedly connected with a piston rod inserted into the through hole, the inner diameter of the through hole is the same as the outer diameter of the piston rod, the bottom of the piston rod is fixedly connected with a piston shaft, the outer diameter of the piston shaft is smaller than the inner diameter of the through hole, the bottom of the piston shaft is abutted against the sealing disc, a driving spring is sleeved outside the piston rod, and.

By adopting the technical scheme, the piston disc and the piston shaft descend together by conveying gas into the gas filling hole, the driving spring is compressed and deformed at the same time, the gas in the driving groove is discharged out of the speed control valve through the scavenging hole, and the piston shaft drives the sealing disc to descend so as to open the through hole; the gas is prevented from being conveyed into the gas filling process, the driving spring pushes the sealing disc to reset, and the air outside the speed control valve enters the driving groove again.

To sum up, the utility model discloses following beneficial effect has:

1. the fluid is conveyed from one end of the speed control valve to the other end of the speed control valve; the fluid entering the regulating valve body is regulated through the regulating assembly, so that the flow of the fluid entering the gas outlet valve body is controlled, and the effect of regulating the flow speed of the fluid is achieved;

2. when the adjusting assembly is disassembled, the locking tube is moved towards the fixing ring, so that the adjusting assembly is pulled out from the fixing hole, and the adjusting assembly is separated from the adjusting valve body; otherwise, the adjusting component is connected with the adjusting valve body; the adjusting component has the effect of facilitating the disassembly and assembly of the adjusting component, and facilitates the replacement or maintenance of the parts of the adjusting component by workers.

Drawings

FIG. 1 is a schematic view of the overall structure of the present embodiment;

FIG. 2 is a cross-sectional view of the salient intake valve structure of the present embodiment;

FIG. 3 is a sectional view showing the structure of the relief regulator valve body according to the present embodiment;

FIG. 4 is an enlarged view of the portion A of FIG. 3 according to the present embodiment;

fig. 5 is a sectional view showing the structure of the air valve body highlighted in the present embodiment.

Reference numerals: 1. an intake valve body; 11. a first air intake hole; 12. a first air outlet hole; 2. an air outlet valve body; 22. closing the groove; 23. a drive slot; 24. a through hole; 25. a fourth air intake hole; 26. a ventilation hole; 3. a regulating valve body; 31. a movable hole; 32. a fixing hole; 33. inserting a tube; 34. a second air intake hole; 35. a tapered hole; 36. operating the ring groove; 4. an adjustment assembly; 41. a fixed shaft; 411. chamfering; 412. a locking ring groove; 42. a positioning ring; 43. fixing the rod; 44. an operation hole; 45. a third air inlet hole; 46. an operating lever; 47. a hand wheel; 5. a locking assembly; 51. a ball bearing; 52. a fixing ring; 53. a clamp spring; 54. a limiting spring; 55. locking the tube; 6. A closure assembly; 61. a sealing block; 62. a guide groove; 63. a guide hole; 64. a closing disk; 641. a closing rod; 65. a seal spring; 7. a drive assembly; 71. a drive cap; 711. air holes are added; 72. a piston disc; 73. a piston rod; 74. a piston shaft; 75. a drive spring.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

The embodiment discloses a speed control valve, as shown in fig. 1 and 3, including air inlet valve body 1, air outlet valve body 2 and adjusting valve body 3, air inlet valve body 1 is connected with adjusting valve body 3, and adjusting valve body 3 is connected with air outlet valve body 2. The upper end of the adjusting valve body 3 is provided with a movable hole 31, the right end of the adjusting valve body 3 is provided with a fixed hole 32 communicated with the movable hole 31, the outer surface of the adjusting valve body 3 is fixedly connected with an insertion pipe 33, and one end of the insertion pipe 33 far away from the fixed hole 32 is provided with a second air inlet 34 communicated with the fixed hole 32.

As shown in fig. 3 and 5, an adjusting assembly 4 for adjusting the flow of the fluid is disposed in the fixing hole 32, the adjusting assembly 4 includes a fixing shaft 41 disposed in the fixing hole 32, and the fixing shaft 41 is detachably connected to the adjusting valve body 3 through a locking assembly 5. The outer surface of the regulating valve body 3 is provided with a plurality of tapered holes 35 communicated with the fixing holes 32, and the tapered holes 35 are arranged along the circumferential array of the regulating valve body 3. The inner diameter of the taper hole 35 decreases from the end far away from the axis of the fixing hole 32 to the end near the axis of the fixing hole 32, and an operation ring groove 36 is formed outside the regulating valve body 3.

As shown in fig. 3 and 4, the locking assembly 5 includes a ball 51 disposed in the tapered hole 35, a fixing ring 52 fixedly connected to the outer surface of the adjustment valve body 3, and a snap spring 53 disposed in the operation ring groove 36, the adjustment valve body 3 is sleeved with a limiting spring 54 and a locking pipe 55 between the fixing ring 52 and the snap spring 53, two ends of the limiting spring 54 are respectively abutted against the fixing ring 52 and the locking pipe 55, and the fixing shaft 41 is provided with a locking ring groove 412 for the ball 51 to be inserted into. When the regulator valve body 3 is coupled with the fixed shaft 41, the ball 51 is inserted into the locking ring groove 412. When the end of the lock pipe 55 remote from the fixed ring 52 abuts against the snap spring 53, the inner surface of the lock pipe 55 abuts against the ball 51 and the outer surface of the regulator valve body 3, respectively.

As shown in fig. 3 and 4, a chamfer 411 is formed at a connection portion between one end of the fixed shaft 41 facing the movable hole 31 and the outer circumferential surface of the fixed shaft 41. The end of the fixed shaft 41 away from the movable hole 31 is fixedly connected with a positioning ring 42, and when the ball 51 is inserted into the locking ring groove 412, the positioning ring 42 abuts against the regulating valve body 3. When the positioning ring 42 abuts against the regulator valve body 3, the fixed shaft 41 is prevented from continuing to move toward the movable hole 31.

As shown in fig. 3 and 4, the adjusting assembly 4 further includes a fixing rod 43 fixedly connected to one end of the fixing shaft 41 close to the movable hole 31, an operation hole 44 penetrating through the fixing rod 43 is formed at one end of the fixing shaft 41 far from the movable hole 31, and a third air inlet 45 communicated with the operation hole 44 is formed on an outer surface of the fixing rod 43. An operating rod 46 is connected to the inner thread of the operating hole 44, and a hand wheel 47 is fixedly connected to one end, far away from the movable hole 31, of the operating rod 46. The rotating hand wheel 47 drives the operating rod 46 to rotate, so that the operating rod 46 moves relative to the fixed rod 43, the second air inlet hole 34, the fixed hole 32, the third air inlet hole 45 and the operating hole 44 are communicated, and the flow rate of the fluid is regulated.

As shown in fig. 1 and fig. 2, the air intake valve body 1 has a first air intake hole 11, one end of the air intake valve body 1 facing the regulating valve body 3 is provided with a first air outlet hole 12 communicated with the first air intake hole 11, and the insertion tube 33 is inserted into the first air outlet hole 12, so that the regulating valve body 3 is connected with the air intake valve body 1.

As shown in fig. 1 and 5, the air outlet valve body 2 is inserted into the movable hole 31, the bottom of the air outlet valve body 2 is provided with a closed groove 22, the upper end of the air outlet valve body 2 is provided with a driving groove 23, one end of the closed groove 22, which is far away from the opening, is provided with a through hole 24 communicated with the driving groove 23, the closed groove 22 is provided with a sealing component 6 for sealing the through hole 24, and a driving component 7 for driving the sealing component 6 to move is arranged in the driving groove 23.

As shown in fig. 1 and 5, the outer surface of the air outlet valve body 2 is provided with a fourth air inlet 25 communicating the movable hole 31 and the through hole 24, the sealing assembly 6 comprises a sealing disc 64 arranged in the sealing groove 22 and a sealing block 61 in threaded connection with the sealing groove 22, the bottom of the sealing block 61 is provided with a guide groove 62, and the outer surface of the sealing block 61 is provided with a guide hole 63 communicating with the sealing groove 22. The closing disk 64 abuts against the end face, far away from the opening, of the closing groove 22, the closing rod 641 penetrating the closing block 61 is fixedly connected to the bottom of the closing disk 64, the sealing spring 65 is sleeved outside the closing rod 641, and two ends of the sealing spring 65 respectively abut against the closing disk 64 and the closing block 61.

As shown in fig. 3 and 4, the outer surface of the outlet valve body 2 is provided with a ventilation hole 26 communicating with the driving groove 23, the driving unit 7 includes a driving cover 71 disposed in the driving groove 23 and a piston disc 72 abutting against the bottom of the driving cover 71, the driving cover 71 seals the driving groove 23, and the upper end of the driving cover 71 is provided with a gas filling hole 711 communicating with the driving groove 23. The outer diameter of the piston disc 72 is the same as the inner diameter of the drive groove 23. A piston rod 73 inserted into the through hole 24 is fixedly connected to the bottom of the piston disc 72, and the inner diameter of the through hole 24 is the same as the outer diameter of the piston rod 73. The bottom of the piston rod 73 is fixedly connected with a piston shaft 74, the outer diameter of the piston shaft 74 is smaller than the inner diameter of the through hole 24, and the bottom of the piston shaft 74 abuts against the closing disc 64. The piston rod 73 is externally sleeved with a driving spring 75, and two ends of the driving spring 75 respectively abut against the piston disc 72 and one end of the driving groove 23 far away from the opening.

The working principle is as follows: first, the air is supplied to the intake hole, the air drives the piston plate 72 and the piston shaft 74 to descend together through the intake hole 711, the driving spring 75 is compressed and deformed, the air in the driving groove 23 is discharged to the outside of the speed control valve through the scavenging hole 26, and the piston shaft 74 drives the closing plate 64 to descend, so that the guide groove 62, the guide hole 63, the through hole 24, the fourth intake port, the movable hole 31, and the fixed hole 32 communicate with each other.

Then, the hand wheel 47 is turned to move the operation lever 46 relative to the fixing lever 43, so that the second air intake hole 34, the fixing hole 32, the third air intake hole 45 and the operation hole 44 are communicated, and the flow rate of the fluid passing through the adjustment assembly 4 is adjusted. Fluid is delivered to the first air inlet hole 11, so that the fluid passes through the air inlet valve body 1, the regulating valve body 3 and the regulating assembly 4 in sequence and flows out of the air outlet valve body 2.

The above description is only the preferred embodiment of the present invention, and is not intended to limit the present invention, any modification, equivalent replacement, or improvement made within the design concept of the present invention should be included within the protection scope of the present invention.

Claims

1. The utility model provides a speed control valve, includes air inlet valve body (1), air outlet valve body (2) and adjusting valve body (3), air inlet valve body (1) is connected with adjusting valve body (3), adjusting valve body (3) are connected with air outlet valve body (2), movable hole (31) have been seted up to adjusting valve body (3) upper end, fixed orifices (32) of intercommunication movable hole (31) are seted up to adjusting valve body (3) right-hand member, fixedly connected with intubate (33) on adjusting valve body (3) surface, second inlet port (34) of intercommunication fixed orifices (32) are seted up to the one end that fixed orifices (32) were kept away from in intubate (33), its characterized in that: an adjusting assembly (4) for adjusting the flow of fluid is arranged in the fixed hole (32), the adjusting assembly (4) comprises a fixed shaft (41) arranged in the fixed hole (32), and the fixed shaft (41) is detachably connected with the adjusting valve body (3) through a locking assembly (5); the outer surface of the adjusting valve body (3) is provided with a tapered hole (35) communicated with the fixing hole (32), the inner diameter of the tapered hole (35) is sequentially reduced from one end far away from the axis of the fixing hole (32) to one end close to the axis of the fixing hole (32), and an operation ring groove (36) is formed outside the adjusting valve body (3); the locking assembly (5) comprises a ball (51) arranged in the tapered hole (35), a fixing ring (52) fixedly connected to the outer surface of the adjusting valve body (3) and a clamp spring (53) arranged in the operation ring groove (36), a limiting spring (54) and a locking pipe (55) which are positioned between the fixing ring (52) and the clamp spring (53) are sleeved outside the adjusting valve body (3), two ends of the limiting spring (54) are respectively abutted against the fixing ring (52) and the locking pipe (55), and the fixing shaft (41) is provided with a locking ring groove (412) for the ball (51) to be embedded in; when one end of the locking tube (55) far away from the fixing ring (52) is abutted against the clamp spring (53), the inner surface of the locking tube (55) is respectively abutted against the ball (51) and the outer surface of the adjusting valve body (3); when the adjusting valve body (3) is connected with the fixed shaft (41), the ball (51) is embedded into the locking ring groove (412).

2. A speed control valve according to claim 1, wherein: the taper holes (35) are arranged in a plurality of circumferential arrays along the adjusting valve body (3).

3. A speed control valve according to claim 1, wherein: a chamfer (411) is formed at the joint of one end, facing the movable hole (31), of the fixed shaft (41) and the outer circumferential surface of the fixed shaft (41).

4. A speed control valve according to claim 1, wherein: one end, far away from the movable hole (31), of the fixed shaft (41) is fixedly connected with a positioning ring (42), and when the ball (51) is embedded into the locking ring groove (412), the positioning ring (42) is abutted to the adjusting valve body (3).

5. A speed control valve according to claim 1, wherein: adjusting part (4) still include fixed connection in fixed axle (41) be close to dead lever (43) of activity hole (31) one end, dead lever (41) are kept away from the one end of activity hole (31) and are seted up operation hole (44) that run through dead lever (43), third air inlet hole (45) of intercommunication operation hole (44) are seted up to dead lever (43) surface, can dismantle in operation hole (44) and be connected with action bars (46).

6. A speed control valve according to claim 5, wherein: and a hand wheel (47) is fixedly connected to one end, far away from the movable hole (31), of the operating rod (46).

7. A speed control valve according to claim 1, wherein: the air inlet valve body (1) is provided with a first air inlet hole (11), one end of the air inlet valve body (1) facing the adjusting valve body (3) is provided with a first air outlet hole (12) communicated with the first air inlet hole (11), and the insertion pipe (33) is inserted into the first air outlet hole (12).

8. A speed control valve according to claim 1, wherein: go out gas valve body (2) and wear to locate movable hole (31), closed groove (22) have been seted up to gas valve body (2) bottom, drive groove (23) have been seted up to gas valve body (2) upper end, closed groove (22) are kept away from open-ended one end and are seted up through hole (24) that communicate drive groove (23), closed groove (22) are provided with seal assembly (6) of sealed through hole (24), be provided with drive assembly (7) that drive seal assembly (6) removed in drive groove (23).

9. A speed control valve according to claim 8, wherein: go out the fourth inlet port (25) that the through hole (24) was seted up to air valve body (2) surface, seal subassembly (6) including set up closed dish (64) and closed piece (61) in closed groove (22), guide slot (62) have been seted up to closed piece (61) bottom, guide hole (63) of intercommunication closed groove (22) are seted up to closed piece (61) surface, open-ended terminal surface is kept away from in closed dish (64) butt closed groove (22), closed dish (64) bottom fixedly connected with wears to establish closed pole (641) of closed piece (61), closed pole (641) overcoat is equipped with sealing spring (65), sealing spring (65) both ends respectively with closed dish (64) and closed piece (61) butt.

10. A speed control valve according to claim 9, wherein: the outer surface of the air outlet valve body (2) is provided with a ventilation hole (26) communicated with the driving groove (23), the driving assembly (7) comprises a driving cover (71) arranged in the driving groove (23) and a piston disc (72) abutted against the bottom of the driving cover (71), the driving cover (71) seals the driving groove (23), the upper end of the driving cover (71) is provided with a gas adding hole (711) communicated with the driving groove (23), the outer diameter of the piston disc (72) is the same as the inner diameter of the driving groove (23), the bottom of the piston disc (72) is fixedly connected with a piston rod (73) inserted into the through hole (24), the inner diameter of the through hole (24) is the same as the outer diameter of the piston rod (73), the bottom of the piston rod (73) is fixedly connected with a piston shaft (74), the outer diameter of the piston shaft (74) is smaller than the inner diameter of the through hole (24), and the bottom of the piston shaft (, and a drive spring (75) is sleeved outside the piston rod (73), and two ends of the drive spring (75) are respectively abutted to one end, far away from the opening, of the piston disc (72) and the drive groove (23).