CN216382781U

CN216382781U - Piston type single-action pneumatic actuator

Info

Publication number: CN216382781U
Application number: CN202123160243.6U
Authority: CN
Inventors: 杜伟荣
Original assignee: Fitok Inc
Current assignee: Fitok Inc
Priority date: 2021-12-15
Filing date: 2021-12-15
Publication date: 2022-04-26
Anticipated expiration: 2031-12-15

Abstract

The utility model relates to a piston type single-action pneumatic actuator which comprises a cylinder body, an end cover, an energy storage cylinder body, an energy storage piston, a rack piston and a rotating shaft, wherein the rotating shaft is vertically arranged in the middle of the cylinder body, the rack piston is arranged on two sides of the rotating shaft and is in gear rack transmission with the rotating shaft, the energy storage cylinder body is arranged at the end part of the cylinder body, the end cover is arranged on the outer side of the energy storage cylinder body, the energy storage piston is arranged on the energy storage cylinder body, the front end of the energy storage piston is connected with the rack piston, and the energy storage piston can axially move relative to the energy storage cylinder body. The utility model adopts compressed gas to store energy to push the piston to drive the actuator to reset, so that the torque output by the actuator is changed less, the structure of the actuator is smaller, and the manufacturing cost is reduced.

Description

Piston type single-action pneumatic actuator

Technical Field

The utility model relates to the field of valves, in particular to a piston type single-action pneumatic actuator.

Background

The pneumatic actuator is an actuating device for opening and closing or adjusting a valve by air pressure drive, and can be divided into a single-acting type and a double-acting type. At the key process control part, a single-action actuator is usually used to form interlocking control with the electromagnetic valve, and when the equipment is abnormal or the gas path is out of gas, the pipeline is cut off in time, so that the safety of production equipment is ensured.

The traditional piston type single-action pneumatic actuator is generally composed of a cylinder body, a piston, a gear shaft, a reset metal spring, a cylinder cover and the like, and the actuator is also called as a spring reset single-action pneumatic actuator. The principle of the spring-return single-action pneumatic actuator is that after compressed air enters the pneumatic actuator, the piston is pushed to move towards one direction and the return metal spring is compressed, and at the moment, the gear rack on the piston drives the gear shaft to rotate towards one direction. When the compressed air is discharged, the piston moves towards the other direction under the action of the return metal spring, and the gear shaft also rotates towards the other direction.

However, since the piston of the spring return single-acting pneumatic actuator also needs to overcome the force of the spring when pushed by air pressure, and the more the spring is compressed, the greater the force that needs to be overcome, resulting in a smaller force that can ultimately be transmitted to the gear shaft and a smaller torque output by the actuator. Therefore, spring return single-acting pneumatic actuators typically vary in output torque from zero to full opening and decrease. In fact the greater the spring rate used, the greater the torque variation. Due to the characteristics of metal materials, the stiffness of the spring cannot be made very small, so the output torque of the spring-return single-action pneumatic actuator usually has 50% variation. To ensure that the minimum torque is required, only actuators with larger cylinder diameters can be selected.

SUMMERY OF THE UTILITY MODEL

In order to solve the defects of the prior art, the utility model provides a piston type single-action pneumatic actuator which comprises a cylinder body, an end cover, an energy storage cylinder body, an energy storage piston, a rack piston and a rotating shaft, wherein the rotating shaft is vertically arranged in the middle of the cylinder body, the rack piston is arranged on two sides of the rotating shaft and is in gear rack transmission with the rotating shaft, the energy storage cylinder body is arranged at the end part of the cylinder body, the end cover is arranged on the outer side of the energy storage cylinder body, the energy storage piston is arranged on the energy storage cylinder body, the front end of the energy storage piston is connected with the rack piston, and the energy storage piston can axially move relative to the energy storage cylinder body.

Furthermore, an inflation valve core is arranged on the energy storage cylinder body, and a spring is arranged on the inflation valve core.

The utility model has the advantages that the compressed gas is adopted to store energy to push the piston to drive the actuator to reset, so that the change of the torque output by the actuator is smaller, the structure of the actuator is smaller, and the manufacturing cost is reduced.

Drawings

FIG. 1 is an exploded perspective view of the present invention;

FIG. 2 is a schematic structural view of the present invention, showing the state after the cavity b is inflated;

FIG. 3 is a schematic structural view of the present invention, showing the state after the cavity b is de-aerated;

Detailed Description

To facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

The utility model comprises a cylinder body 1, an end cover 2, an energy storage cylinder body 3, an energy storage piston 6, a rack piston 7 and a rotating shaft 8. The cylinder body 1 is square and has a through cavity along the long axis direction. The shaft 8 is cylindrical and has teeth 28 in the middle. The rotating shaft 8 is vertically arranged in the cylinder body 1, the bottom of the rotating shaft is embedded in a lower step hole 22 in the middle of the cylinder body 1, an upper step hole 20 extends from the upper end of the rotating shaft, and

sealing elements

17 and 18 are respectively arranged between the rotating shaft 8 and the upper step hole 20 as well as between the rotating shaft and the lower step hole 22. The cylinder body 1 is also provided with an indicator 11, and the indicator 11 is connected to the upper end of the rotating shaft 8 through a screw 19. The rack piston 7 is arranged on two sides of the rotating shaft 8, the rack piston 7 comprises a rack front end 23 and a round cake rear end 25, the rack front end 23 is in gear-rack transmission with teeth 28 in the middle of the rotating shaft 8, and the round cake rear end 25 is attached to the cavity wall 10 of the cylinder body 1. To ensure sealing, the rear end 25 of the disk is provided with an annular groove 26, in which annular groove 26 a seal 16 is provided. The energy storage cylinder bodies 3 are arranged at two ends of the cylinder body 1, the end covers 2 are arranged on the outer sides of the energy storage cylinder bodies 3, the energy storage cylinder bodies 3 are connected with the end covers 2 through screws 35, and the end covers 2 are fixed at the end portions of the cylinder body 1 through screws 37. And a sealing element 15 is arranged on the connecting end surface of the energy storage cylinder 3 and the end cover 2. The energy storage piston 6 is cylindrical and is arranged in a central hole 30 of the energy storage cylinder 3, a groove is further arranged on the central hole 30, a sealing element 14 is arranged in the groove, and the energy storage piston 6 can axially extend and retract in the central hole 30. The energy accumulating piston 6 is supported by the front end against the back end 25 of the circular cake of the rack piston 7, and the back end is provided with a projection 62 for limiting the stroke.

When compressed air is introduced into the rack piston 7 to form a cavity b with the cylinder body 1, the rack piston 7 moves towards two ends, the rotating shaft 8 rotates anticlockwise, and the rack piston 7 simultaneously pushes the energy storage piston 6 to move towards two sides. The pressure in the cavity a formed by the end cover 2 and the energy storage cylinder 3 slightly rises at the same time. When the compressed air in the cavity b loses air, the rack piston 7 moves towards the rotating shaft 8 under the pushing of the energy storage piston 6, and meanwhile, the rotating shaft 8 is driven to rotate clockwise. When the rack piston 7 needs the same thrust, the diameter of the energy storage piston 6 can be reduced by increasing the air pressure of the cavity a. Compared with the traditional spring return single-action pneumatic actuator, the utility model has the advantages that the thrust change provided by the energy storage piston 6 can be reduced to below 10% under the same installation height.

The energy storage cylinder body 3 can also be provided with an inflation valve core 4, the inflation valve core 4 is positioned in the cavity a, the pointed front end of the inflation valve core 4 is inserted into an inflation hole 32 on the energy storage cylinder body 3, the smooth rear end is provided with a spring 5, and the tail end of the spring 5 abuts against the inner end face of the end cover 2. When the air pressure of the cavity a is too low and needs to be inflated, the air pressure is used for jacking the inflation valve core 4, and when the air pressure of the cavity a reaches, the inflation valve core 4 resets under the action of the air pressure and the spring 5, and inflation is completed. Further, a sealing member 13 is arranged between the charging valve core 4 and the energy storage cylinder 3.

The utility model has been described with reference to a preferred embodiment, to which the above mentioned examples do not limit the utility model, and from reading the present description a person skilled in the art will be able to conceive of numerous modifications and variations to the structure, any obvious alternative being within the scope of protection of the utility model without departing from the inventive concept.

Claims

1. The utility model provides a piston single-action pneumatic actuator, its characterized in that includes cylinder body (1), end cover (2), energy storage cylinder body (3), energy storage piston (6), rack piston (7), pivot (8) set up perpendicularly the middle part of cylinder body (1), rack piston (7) set up pivot (8) both sides, and with pivot (8) rack and pinion transmission, energy storage cylinder body (3) set up the tip of cylinder body (1), end cover (2) set up the outside of energy storage cylinder body (3), energy storage piston (6) set up on energy storage cylinder body (3), the front end of energy storage piston (6) with rack piston (7) are connected, energy storage piston (6) can be relative energy storage cylinder body (3) axial motion.

2. A piston-type single-acting pneumatic actuator as claimed in claim 1, characterized in that said energy-accumulating cylinder (3) is provided with an inflating valve spool (4), said inflating valve spool (4) being provided with a spring (5).