Multi-piston pneumatic actuator

Abstract

The multi-piston pneumatic actuator comprises a middle shell, an action shaft is movably connected between the middle ends of the two sides of the middle shell through bearings, and a gear is fixedly installed at the middle end of the action shaft. Through the arrangement of the middle shell, the piston cylinder and the action pistons, pressure energy of compressed air can be converted into mechanical energy, through the symmetrical linkage design of the gear, the double-set toothed plate and the double-set action pistons, the action shaft can be driven to rotate, and the valve is correspondingly controlled to be opened and closed; meanwhile, through the arrangement of an air guide groove, an air guide cavity, a movable column, an opposite penetrating locking rod and a locking hole, when the acting piston moves to the limiting position, the opposite penetrating locking rod can be automatically driven to be inserted into or retreat from the locking hole in the piston cylinder through the working air pressure in the pneumatic actuator, and therefore the working efficiency is improved. And mechanical locking and unlocking of the position of the acting piston are achieved.

Description

Technical Field

[0001] This invention relates to the field of pneumatic actuator technology, specifically a multi-piston pneumatic actuator. Background Technology

[0002] Pneumatic actuators, as core actuators in industrial automation control systems and fluid transport systems, are widely used in various industrial fields such as petroleum, chemical, metallurgy, and power. Their main function is to convert the pressure energy of compressed air into mechanical energy to drive valves and other actuators to open, close, or regulate. They are directly related to the continuity, stability, and safety of industrial production processes and are key equipment to ensure the normal operation of various industrial facilities. Among various pneumatic actuators, double-acting cylinder actuators have become one of the most widely used types in the industrial field due to their advantages such as simple structure, rapid response, and stable output force. This type of actuator relies entirely on the alternating action of compressed air on both sides of the piston to achieve reciprocating motion in both directions of extension and retraction, thereby driving the valve to complete the opening and closing action and meeting the control requirements for fluid flow in industrial production.

[0003] However, the operation of traditional double-acting cylinder actuators relies entirely on compressed air for power. In actual industrial applications, when a double-acting cylinder actuator drives a valve to maintain a stable open or closed state, it is often affected by factors such as external air pressure fluctuations and changes in fluid pressure within the pipeline. This causes the pressure balance on both sides of the cylinder piston to be disrupted, leading to unexpected malfunctions of the valve. Such malfunctions not only disrupt the stability of the industrial production process and affect production efficiency, but may also lead to safety hazards such as pipeline leaks and equipment damage in severe cases, causing great inconvenience and losses to industrial production. Summary of the Invention

[0004] The purpose of this invention is to provide a multi-piston pneumatic actuator with an automatic locking limit structure, which avoids fluctuations in valve opening and closing due to air pressure fluctuations, thereby improving the stability of valve components.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a multi-piston pneumatic actuator, comprising an intermediate shell, an actuating shaft movably connected between the middle ends of the two sides of the intermediate shell via bearings, a gear fixedly installed at the middle end of the actuating shaft, piston cylinders fixedly installed on both sides of the intermediate shell, locking holes provided on both sides of the inner cavity of the piston cylinder, an actuating piston slidably connected to the middle end of the inner cavity of the piston cylinder, a toothed plate fixedly installed on the side of the two actuating pistons that are close to each other, the toothed plate meshing with the gear, air guide grooves provided on both sides of the actuating piston, an air guide chamber provided at the middle end of the actuating piston, the air guide chamber communicating with the air guide groove, a movable column slidably connected between the two ends of the air guide chamber, and a through locking rod fixedly connected to the middle end of the movable column.

[0006] As a preferred embodiment, a receiving hole is provided at the middle of the side of the actuating piston. The receiving hole is connected to the air guide chamber. A threaded plug is threadedly connected to the surface of the receiving hole. A pressure spring is sleeved in the inner cavity of the threaded plug. A positioning pin is sleeved between the surface of the pressure spring and the surface of the receiving hole. The surface of the positioning pin is slidably connected to the surface of the movable column.

[0007] As a preferred embodiment, both ends of the movable column are provided with positioning pin grooves, the positioning pin grooves are annular in shape, and both ends of the movable column are fixedly installed with column sealing rings, the surface of the column sealing rings being slidably connected to the surface of the air guide cavity.

[0008] As a preferred embodiment, guide copper sleeves are fixedly connected to both sides of the actuating piston, the surface of the through-locking rod is slidably connected to the inner cavity of the guide copper sleeve, and guide balls are embedded on both sides of the through-locking rod, the surface of the guide balls being slidably connected to the inner cavity of the piston cylinder.

[0009] As a preferred embodiment, piston sealing rings are fixedly installed at both ends of the actuating piston, and the surface of the piston sealing rings is slidably connected to the inner cavity of the piston cylinder. A housing sealing gasket is fixedly installed on the side of the two piston cylinders that are close to each other, and the surface of the housing sealing gasket is in contact with the surface of the intermediate shell.

[0010] As a preferred embodiment, a sealing cover is fixedly installed on the side of the two piston cylinders that are far apart from each other, and a cover sealing gasket is fixedly installed on the side of the two sealing cover that are close to each other, with the surface of the cover sealing gasket contacting the surface of the piston cylinder.

[0011] As a preferred embodiment, limit rings are provided at both ends of the piston cylinder cavity.

[0012] As a preferred embodiment, guide holes are provided at both ends of the inner cavity of the intermediate shell, and guide rods are slidably connected to the surface of the guide holes, with the side of the guide rods fixedly installed on the surface of the actuating piston.

[0013] As a preferred embodiment, guide strips are fixedly connected to both sides of the inner cavity of the intermediate shell, and the number of guide strips is four. Guide grooves are provided at both ends of the two toothed plates on opposite sides. The surfaces of the guide grooves are slidably connected to the surfaces of the guide strips. Shaft seals are fixedly installed at the middle ends of both sides of the intermediate shell, and the surfaces of the shaft seals are sleeved on the surfaces of the actuating shafts.

[0014] As a preferred embodiment, an air supply interface is fixedly installed at the middle of the front surface of the intermediate shell, and an air supply pipe is fixedly installed between the front surfaces of the two piston cylinders.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention, through the arrangement of an intermediate shell, piston cylinder, and actuating piston, can convert the pressure energy of compressed air into mechanical energy. Through the symmetrical linkage design of gears, double-set toothed plates, and double-set actuating pistons, it can drive the actuating shaft to rotate and correspondingly control the valve to open and close, ensuring stable output torque and precise operation. Furthermore, through the arrangement of air guide grooves, air guide chambers, movable columns, through-locking rods, and locking holes, when the actuating piston moves to its limit position, the working air pressure inside the pneumatic actuator can automatically drive the through-locking rod to insert or exit the locking hole in the piston cylinder, achieving mechanical locking and unlocking of the actuating piston position. This prevents subsequent displacement of the actuating piston due to air pressure fluctuations or fluid pressure effects, ensuring the stability of the valve's opening and closing state and guaranteeing the continuity and safety of the industrial production process.

[0016] 2. By using a threaded plug, this invention can support the pressure spring and the positioning pin inside the receiving hole. Under the pre-compression of the pressure spring, the positioning pin can be pushed. When the movable column and the through-locking rod move and are inserted into the corresponding locking hole, the positioning pin groove at one end of the movable column corresponds to the position of the positioning pin. Under the push of the pressure spring, the positioning pin can be inserted into the positioning pin groove, which can generate a certain positioning resistance on the movable column and prevent the through-locking rod from disengaging from the locking hole in the case of air cut-off or non-pneumatic conditions. Attached Figure Description

[0017] Figure 1 This is a perspective view of the present invention; Figure 2 This is a schematic diagram of the cross-sectional structure on the left side of the present invention; Figure 3 This is a top view cross-sectional structural diagram of the present invention; Figure 4 For the present invention Figure 3 Enlarged view of section A in the image; Figure 5 This is a schematic diagram of the piston structure of the present invention; Figure 6 This is a top view cross-sectional structural diagram of the piston of the present invention; Figure 7 For the present invention Figure 6 A magnified view of section B in the image.

[0018] In the diagram: 1. Intermediate shell; 2. Piston cylinder; 3. Air supply interface; 4. Air supply pipe; 5. Sealing cover; 6. Actuating shaft; 7. Shaft seal ring; 8. Gear; 9. Gear plate; 10. Guide bar; 11. Guide groove; 12. Locking hole; 13. Guide hole; 14. Side cover sealing gasket; 15. Limiting protrusion ring; 16. Actuating piston; 17. Shell sealing gasket; 18. Guide rod; 19. Piston seal ring; 20. Through locking rod; 21. Guide copper sleeve; 22. Guide ball; 23. Air guide chamber; 24. Movable column; 25. Column seal ring; 26. Receiving hole; 27. Threaded plug; 28. Compression spring; 29. ​​Positioning pin; 30. Positioning pin groove; 31. Air guide groove. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0021] Example 1: Please refer to Figures 1-7 As shown, the present invention provides a multi-piston pneumatic actuator, including an intermediate shell 1. An actuating shaft 6 is movably connected between the middle ends of the two sides of the intermediate shell 1 via bearings. A gear 8 is fixedly installed at the middle end of the actuating shaft 6. Piston cylinders 2 are fixedly installed on both sides of the intermediate shell 1. Locking holes 12 are provided on both sides of the inner cavity of the piston cylinder 2. An actuating piston 16 is slidably connected to the middle end of the inner cavity of the piston cylinder 2. A toothed plate 9 is fixedly installed on the side of the two actuating pistons 16 that are close to each other. The toothed plate 9 meshes with the gear 8. Air guide grooves 31 are provided on both sides of the actuating piston 16. An air guide chamber 23 is provided at the middle end of the actuating piston 16. The air guide chamber 23 is connected to the air guide groove 31. A movable column 24 is slidably connected between the two ends of the air guide chamber 23. A through locking rod 20 is fixedly connected to the middle end of the movable column 24.

[0022] In this technical solution, during use, when high-pressure gas enters from the intermediate shell 1, the gas pressure continuously pushes the two sets of actuating pistons 16 to move away from each other along the interior of the piston cylinder 2. The movement of the actuating pistons 16 drives the toothed plate 9 to move, and drives the gear 8 and the actuating shaft 6 to rotate along the bearing on the intermediate shell 1, thereby driving the connected valve to rotate through the actuating shaft 6. When the actuating piston 16 moves to its limit position, it indicates that the valve is fully open. At this time, the through-locking rod 20 inside the actuating piston 16 can correspond to a set of locking holes 12 inside the piston cylinder 2. Influenced by the air pressure between the two sets of actuating pistons 16, the air can enter the air guide chamber 23 through the air guide groove 31 on one side of the actuating piston 16, and push the movable column 24 and the through-locking rod 20 to move, so that the through-locking rod 20 can be inserted into the corresponding locking hole 12, thereby locking the position between the actuating piston 16 and the piston cylinder 2, preventing subsequent action caused by air pressure fluctuations between the two sets of actuating pistons 16 and the valve being affected by fluid pressure, ensuring the stability of the operation of this pneumatic actuator and the valve opening state. When it is necessary to open the valve, exhaust gas is vented from the intermediate shell 1 and high-pressure gas is directed to... Input is made into the two sets of piston cylinders 2. During this process, under the action of high-pressure gas, the gas can enter the other side of the air guide chamber 23 through the air guide groove 31 on the other side of the actuating piston 16, and accordingly push the movable column 24 and the through-locking rod 20 to move, so that the through-locking rod 20 can disengage from the locking hole 12. At this time, the lock between the actuating piston 16 and the piston cylinder 2 is released. Then, under the push of high-pressure gas, the two sets of actuating pistons 16 can be pushed to move towards each other. The movement of the actuating piston 16 drives the toothed plate 9 to move, and drives the gear 8 and the actuating shaft 6 to rotate, so as to drive the connected valve to rotate through the actuating shaft 6. When the actuating piston 16 moves to its limit position, it indicates that the valve is in a fully closed state. At this time, the through-locking rod 20 inside the actuating piston 16 can correspond to another set of locking holes 12 inside the piston cylinder 2. At the same time, under the influence of the air pressure inside the piston cylinder 2, the movable column 24 can be pushed to move with the through-locking rod 20, so that the through-locking rod 20 can be inserted into the locking hole 12, thereby locking the position between the actuating piston 16 and the piston cylinder 2. This prevents subsequent action caused by air pressure fluctuations inside the piston cylinder 2 and the valve being affected by fluid pressure, ensuring the stability of the operation of this pneumatic actuator and the valve's closed state.

[0023] Example 2: Based on Example 1, the present invention as follows... Figure 7As shown, a receiving hole 26 is provided at the middle of the side of the actuating piston 16. The receiving hole 26 is connected to the air guide chamber 23. A threaded plug 27 is threadedly connected to the surface of the receiving hole 26. A pressure spring 28 is sleeved in the inner cavity of the threaded plug 27. A positioning pin 29 is sleeved between the surface of the pressure spring 28 and the surface of the receiving hole 26. The surface of the positioning pin 29 is slidably connected to the surface of the movable column 24. Positioning pin grooves 30 are provided at both ends of the movable column 24. The positioning pin grooves 30 are annular in shape. Column sealing rings 25 are fixedly installed at both ends of the movable column 24. The surface of the column sealing rings 25 is slidably connected to the surface of the air guide chamber 23.

[0024] In this technical solution, by setting the threaded plug 27, the pressure spring 28 and the positioning pin 29 can be supported inside the receiving hole 26. Under the pre-pressurized action of the pressure spring 28, the positioning pin 29 can be pushed. When the movable column 24 and the through locking rod 20 move and are inserted into the corresponding locking hole 12, the positioning pin groove 30 at one end of the movable column 24 can correspond to the position of the positioning pin 29. Under the push of the pressure spring 28, the positioning pin 29 can be inserted into the positioning pin groove 30, which can generate a certain positioning resistance on the movable column 24, preventing the through locking rod 20 from disengaging from the locking hole 12 in the case of air cut-off and non-pneumatic conditions. By setting the column sealing ring 25, the sealing performance between the movable column 24 and the air guide cavity 23 is effectively improved.

[0025] Example 3: Based on Example 1, the present invention as follows Figures 1-6 As shown, guide copper sleeves 21 are fixedly connected to both sides of the actuating piston 16. The surface of the through-locking rod 20 is slidably connected to the inner cavity of the guide copper sleeve 21. Guide balls 22 are embedded on both sides of the through-locking rod 20. The surface of the guide balls 22 is slidably connected to the inner cavity of the piston cylinder 2. Piston sealing rings 19 are fixedly installed at both ends of the actuating piston 16. The surface of the piston sealing rings 19 is slidably connected to the inner cavity of the piston cylinder 2. A housing sealing gasket 17 is fixedly installed on the side of the two piston cylinders 2 that is close to each other. The surface of the housing sealing gasket 17 contacts the surface of the intermediate shell 1. A sealing side cover 5 is fixedly installed on the side of the two piston cylinders 2 that is far from each other. A side cover sealing gasket 14 is fixedly installed on the side of the two sealing side covers 5 that is close to each other. The surface of the side cover sealing gasket 14 contacts the surface of the piston cylinder 2. Limiting protrusions 15 are provided at both ends of the inner cavity of the piston cylinder 2.

[0026] In this technical solution, the guide copper sleeve 21 is used to guide the through-locking rod 20 and prevent it from shifting. The guide ball 22 is used to effectively reduce the frictional resistance between the through-locking rod 20 and the piston cylinder 2. The piston sealing ring 19 is used to effectively improve the sealing performance between the two ends of the piston 16 and the piston cylinder 2. The housing sealing gasket 17 is used to effectively improve the sealing performance between the piston cylinder 2 and the intermediate shell 1. The sealing side cover 5 and the side cover sealing gasket 14 are used to seal the side of the piston cylinder 2 while facilitating maintenance of the inside of the piston cylinder 2. The limiting protrusion ring 15 is used to precisely limit the movement stroke of the piston 16 inside the piston cylinder 2.

[0027] Example 4: Based on Example 1, the present invention is as follows... Figure 1 , Figure 2 , Figure 3 and Figure 5 As shown, guide holes 13 are provided at both ends of the inner cavity of the intermediate shell 1. Guide rods 18 are slidably connected to the surface of the guide holes 13. The side of the guide rods 18 is fixedly installed on the surface of the actuating piston 16. Guide bars 10 are fixedly connected to both sides of the inner cavity of the intermediate shell 1. There are four guide bars 10. Guide grooves 11 are provided at both ends of the two toothed plates 9 on opposite sides. The surface of the guide grooves 11 is slidably connected to the surface of the guide bars 10. Shaft seal rings 7 are fixedly installed at the middle of both sides of the intermediate shell 1. The surface of the shaft seal rings 7 is sleeved on the surface of the actuating shaft 6. An air supply interface 3 is fixedly installed at the middle of the front surface of the intermediate shell 1. An air supply pipe 4 is fixedly installed between the front surfaces of the two piston cylinders 2.

[0028] In this technical solution, the guide hole 13 and guide rod 18 are used to guide the piston 16 and prevent it from rotating during movement. The guide bar 10 and guide groove 11 are used to guide the toothed plate 9 and prevent it from shifting during movement. The shaft seal ring 7 is used to effectively improve the sealing between the shaft 6 and the intermediate shell 1. The air supply interface 3 and air supply pipe 4 are used to facilitate connection with external pipelines.

[0029] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A multi-piston pneumatic actuator, comprising an intermediate housing (1), characterized in that: An actuating shaft (6) is movably connected between the middle ends of the two sides of the intermediate shell (1) via bearings. A gear (8) is fixedly installed at the middle end of the actuating shaft (6). Piston cylinders (2) are fixedly installed on both sides of the intermediate shell (1). Locking holes (12) are provided on both sides of the inner cavity of the piston cylinder (2). An actuating piston (16) is slidably connected to the middle end of the inner cavity of the piston cylinder (2). A toothed plate (9) is fixedly installed on the side of the two actuating pistons (16) that are close to each other. The toothed plate (9) meshes with the gear (8). Air guide grooves (31) are provided on both sides of the actuating piston (16). An air guide chamber (23) is provided at the middle end of the actuating piston (16). The air guide chamber (23) is connected to the air guide groove (31). A movable column (24) is slidably connected between the two ends of the air guide chamber (23). A through locking rod (20) is fixedly connected to the middle end of the movable column (24).

2. The multi-piston pneumatic actuator according to claim 1, characterized in that: The middle of the side of the actuating piston (16) is provided with a receiving hole (26), which is connected to the air guide chamber (23). A threaded plug (27) is threadedly connected to the surface of the receiving hole (26). A pressure spring (28) is sleeved in the inner cavity of the threaded plug (27). A positioning pin (29) is sleeved between the surface of the pressure spring (28) and the surface of the receiving hole (26). The surface of the positioning pin (29) is slidably connected to the surface of the movable column (24).

3. A multi-piston pneumatic actuator according to claim 1, characterized in that: Both ends of the movable column (24) are provided with positioning pin grooves (30), the positioning pin grooves (30) are annular in shape, and both ends of the movable column (24) are fixedly installed with column sealing rings (25), the surface of the column sealing rings (25) is slidably connected to the surface of the air guide cavity (23).

4. A multi-piston pneumatic actuator according to claim 1, characterized in that: The piston (16) is fixedly connected to both sides of the guide copper sleeve (21), the surface of the through locking rod (20) is slidably connected to the inner cavity of the guide copper sleeve (21), and both sides of the through locking rod (20) are embedded with guide balls (22), the surface of the guide balls (22) is slidably connected to the inner cavity of the piston cylinder (2).

5. A multi-piston pneumatic actuator according to claim 1, characterized in that: Both ends of the piston (16) are fixedly installed with piston seal rings (19). The surface of the piston seal rings (19) is slidably connected to the inner cavity of the piston cylinder (2). The two piston cylinders (2) are fixedly installed with a housing seal gasket (17) on the side that is close to each other. The surface of the housing seal gasket (17) is in contact with the surface of the intermediate shell (1).

6. A multi-piston pneumatic actuator according to claim 1, characterized in that: A sealing cover (5) is fixedly installed on the side of the two piston cylinders (2) that is far apart from each other, and a side cover sealing gasket (14) is fixedly installed on the side of the two sealing cover (5) that is close to each other, and the surface of the side cover sealing gasket (14) is in contact with the surface of the piston cylinder (2).

7. A multi-piston pneumatic actuator according to claim 1, characterized in that: Limiting rings (15) are provided at both ends of the inner cavity of the piston cylinder (2).

8. A multi-piston pneumatic actuator according to claim 1, characterized in that: Both ends of the inner cavity of the intermediate shell (1) are provided with guide holes (13), and guide rods (18) are slidably connected to the surface of the guide holes (13). The side of the guide rods (18) is fixedly installed on the surface of the action piston (16).

9. A multi-piston pneumatic actuator according to claim 1, characterized in that: Guide strips (10) are fixedly connected to both sides of the inner cavity of the intermediate shell (1). There are four guide strips (10). Guide grooves (11) are provided at both ends of the two toothed plates (9) on opposite sides. The surface of the guide grooves (11) is slidably connected to the surface of the guide strips (10). Shaft seals (7) are fixedly installed at the middle ends of both sides of the intermediate shell (1). The surface of the shaft seals (7) is sleeved on the surface of the actuating shaft (6).

10. A multi-piston pneumatic actuator according to claim 1, characterized in that: An air supply port (3) is fixedly installed at the middle of the front surface of the intermediate shell (1), and an air supply pipe (4) is fixedly installed between the front surfaces of the two piston cylinders (2).

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