High-sealing-performance piston type pneumatic actuator

Abstract

The utility model discloses a high sealing piston type pneumatic actuator which comprises an actuator body and a butterfly valve, the actuator body is composed of a shell, a sealing cover, a first piston, a second piston, a gear, an angle adjusting block, an angle display assembly, a first rack, a second rack and a buffering assembly, and two rotating shafts are rotationally connected in the shell; the two rotating shafts are located on the two sides of the angle adjusting block respectively, and the outer wall, located in the cavity of the shell, of each rotating shaft is in threaded connection with a limiting block. Through threaded connection between the rotating shafts and the limiting blocks, when the rotating shafts rotate, the positions of the limiting blocks are changed, and therefore the purpose of limiting the rotating angle of the angle adjusting block is achieved; and through cooperation of the positioning shaft and the sealing ring, axial movement of the rotating shaft is limited, and on the premise that it is guaranteed that the positioning shaft and the rotating shaft can rotate, the sealing performance between the positioning shaft and the shell is improved, and the problem of air leakage in a cavity of the shell is solved.

Description

Technical Field

[0001] The utility model relates to the technical field of pneumatic actuators, in particular to a high-sealing piston-type pneumatic actuator. Background Art

[0002] Pneumatic actuators are devices that use air pressure to drive the opening, closing or regulating of valves. They are also called pneumatic actuators or pneumatic devices, but they are generally referred to as pneumatic heads. Pneumatic actuators are sometimes equipped with certain auxiliary devices, commonly used are valve positioners and handwheel mechanisms. The function of the valve positioner is to use the feedback principle to improve the performance of the actuator so that the actuator can achieve accurate positioning according to the control signal of the controller. The function of the handwheel mechanism is to directly manipulate the control valve when the control system fails due to power outages, gas outages, no controller output or actuator failure, so as to maintain normal production.

[0003] The piston pneumatic actuator uses gas to rush into the enclosed space between the two pistons, causing the two pistons to move away from each other, and driving the two connected racks to move away from each other, causing the gear meshing with the two gear sleeves to rotate, thereby driving the valve to rotate and realize the movement of the valve opening.

[0004] The existing piston pneumatic actuator limits the rotation angle of the internal gear by screwing and moving the bolt to adjust the valve opening and closing angle. However, a gap is easily generated at the threaded connection between the bolt and the pneumatic actuator housing, resulting in air leakage in the enclosed space between the two pistons. In addition, the connection between the pneumatic actuator and the valve is usually achieved by screwing the bolt through the flange on the valve and onto the bottom of the pneumatic actuator housing. In actual operation, the installation efficiency is low and it is not convenient for subsequent disassembly and maintenance. Therefore, a highly sealed piston pneumatic actuator is needed to meet the needs. Summary of the invention

[0005] The purpose of the utility model is to provide a piston-type pneumatic actuator with high sealing performance to solve the problems raised in the above-mentioned background technology.

[0006] To achieve the above object, the utility model provides the following technical solutions: a high-sealing piston-type pneumatic actuator, including an actuator body and a butterfly valve. The actuator body is composed of a housing, a cover, a first piston, a second piston, a gear, an angle adjustment block, an angle display component, a first rack, a second rack, and a buffer component. Two rotating shafts are rotatably connected in the housing, and the two rotating shafts are respectively located on both sides of the angle adjustment block. A limiting block is threadedly connected to the outer wall of each rotating shaft located in the housing chamber, and the two limiting blocks are both located at the same end of the angle adjustment block. Positioning shafts are provided at both ends of the two rotating shafts, and the positioning shafts are rotatably connected in the housing. A sealing ring is fitted inside the outer wall of each positioning shaft. The butterfly valve is composed of a flange, a valve body, a valve stem, and a butterfly plate. The valve stem is connected to the gear, the flange is connected to the housing, and a plurality of sliding rods are slidably connected to the bottom end of the housing. A spring piece is connected to one end of the sliding rod located inside the housing, and a compression spring is connected between the spring piece and the housing. The sliding rod penetrates through the bottom outer wall of the flange and is rotatably connected with a U-shaped stopper. The width of the U-shaped stopper is smaller than the diameter of the screw through-hole on the flange, and the length of the U-shaped stopper from the connection point to both ends is greater than the radius of the screw through-hole on the flange.

[0007] Preferably, a thread is provided on the outer wall of the rotating shaft, and a threaded hole is provided on the limiting block, and the specifications of the threaded hole and the thread are adapted to each other.

[0008] Preferably, a guide rod is connected between the inner walls of the housing chamber, the guide rod is parallel to the rotating shaft, and the limiting block is slidably connected to the guide rod.

[0009] Preferably, a knob is connected to each positioning shaft, and the knob is located outside the housing.

[0010] Preferably, a plurality of positioning protrusions are provided at the bottom of the housing, the positioning protrusions correspond to the positions of the screw through-holes on the flange, and the sliding rods are slidably connected in the positioning protrusions.

[0011] Preferably, a first sliding hole is provided in the positioning protrusion, the diameter of the first sliding hole is adapted to the diameter of the sliding rod, and second sliding holes are provided on both the positioning protrusion and the bottom of the housing, the diameter of the second sliding hole is adapted to the diameter of the spring piece, and the compression spring is connected in the second sliding hole and is located at the connection with the first sliding hole.

[0012] Preferably, the length of the open end of the U-shaped stopper slot from the connection point is smaller than the length of the other end of the U-shaped stopper from the connection point.

[0013] The beneficial effects of the utility model are:

[0014] In the present utility model, through the threaded connection between the rotating shaft and the limiting block, when the rotating shaft rotates, the position of the limiting block is changed, so as to limit the rotation angle of the angle adjusting block, and further achieve the angle adjustment effect of opening the valve. Moreover, through the cooperation of the positioning shaft and the sealing ring, the axial movement of the rotating shaft is restricted, and on the premise of ensuring that the positioning shaft and the rotating shaft can rotate, the sealing performance between the positioning shaft and the housing is improved, preventing air leakage in the housing chamber.

[0015] In the present utility model, through the cooperation between the sliding rod, the spring piece, the compression spring and the U-shaped stopper, the connection between the housing and the flange is realized, and relatively, the connection between the pneumatic actuator and the valve is realized, and the installation and disassembly between the pneumatic actuator and the valve are made more convenient, which is beneficial to later maintenance. Brief Description of the Drawings

[0016] Figure 1 is a schematic structural diagram of a highly sealed piston-type pneumatic actuator proposed by the present utility model;

[0017] Figure 2 is an exploded structural schematic diagram of the actuator body of a highly sealed piston-type pneumatic actuator proposed by the present utility model;

[0018] Figure 3 is a schematic top view sectional structural diagram of the rotating shaft of a highly sealed piston-type pneumatic actuator proposed by the present utility model;

[0019] Figure 4 is of a highly sealed piston-type pneumatic actuator proposed by the present utility model Figure 3 magnified structural schematic diagram at A;

[0020] Figure 5 is a schematic structural diagram of the butterfly valve of a highly sealed piston-type pneumatic actuator proposed by the present utility model;

[0021] Figure 6 is a schematic sectional structural diagram of the connection test between the housing and the flange of a highly sealed piston-type pneumatic actuator proposed by the present utility model;

[0022] Figure 7 is of a highly sealed piston-type pneumatic actuator proposed by the present utility model Figure 6 magnified structural schematic diagram at B.

[0023] In the figure:

[0024] 1. Actuator body; 101. Housing; 102. Sealing cover; 103. First piston; 104. Second piston; 105. Gear; 106. Angle adjusting block; 107. Angle display component; 108. First rack; 109. Second rack; 110. Buffer component;

[0025] 2. Butterfly valve; 201. Flange; 202. Valve body; 203. Valve stem; 204. Butterfly plate;

[0026] 3. Rotating shaft; 4. Limit block; 5. Positioning shaft; 6. Sealing ring; 7. Slide bar; 8. Spring piece; 9. Compression spring; 10. U-shaped stop block; 11. Thread; 12. Threaded hole; 13. Guide bar; 14. Knob; 15. Positioning convex block; 16. First sliding hole; 17. Second sliding hole. Detailed implementation manner

[0027] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0028] Refer to Figures 1-7 , a high-sealing piston-type pneumatic actuator, including an actuator body 1 and a butterfly valve 2. The actuator body 1 is composed of a housing 101, a cover 102, a first piston 103, a second piston 104, a gear 105, an angle adjustment block 106, an angle display component 107, a first rack 108, a second rack 109 and a buffer component 110. Two rotating shafts 3 are rotatably connected in the housing 101, and the two rotating shafts 3 are respectively located on both sides of the angle adjustment block 106. A limit block 4 is threadedly connected to the outer wall of each rotating shaft 3 located in the chamber of the housing 101. The two limit blocks 4 are both located at the same end of the angle adjustment block 106. Positioning shafts 5 are provided at both ends of the two rotating shafts 3. The positioning shafts 5 are rotatably connected in the housing 101. A sealing ring 6 is fitted inside the outer wall of each positioning shaft 5. The butterfly valve 2 is composed of a flange 201, a valve body 202, a valve stem 203 and a butterfly plate 204. The valve stem 203 is connected to the gear 105. The flange 201 is connected to the housing 101. A plurality of slide bars 7 are slidably connected inside the bottom end of the housing 101. A spring piece 8 is connected to the end of the slide bar 7 located inside the housing 101. A compression spring 9 is connected between the spring piece 8 and the housing 101. The slide bar 7 passes through the bottom end outer wall of the flange 201 and is rotatably connected with a U-shaped stop block 10. The width of the U-shaped stop block 10 is smaller than the diameter of the screw through hole on the flange 201. The length of the U-shaped stop block 10 from the connection point to both ends is greater than the radius of the screw through hole on the flange 201.

[0029] Through the threaded connection between the rotating shaft 3 and the limit block 4, when the rotating shaft 3 rotates, the position of the limit block 4 is changed, so as to achieve the purpose of limiting the rotation angle of the angle adjustment block 106, and further achieve the angle adjustment effect of opening the valve. And through the cooperation of the positioning shaft 5 and the sealing ring 6, the axial movement of the rotating shaft 3 is restricted, and on the premise of ensuring that the positioning shaft 5 and the rotating shaft 3 can rotate, the sealing performance between the positioning shaft 5 and the housing 101 is improved, preventing air leakage in the chamber of the housing 101;

[0030] Through the cooperation among the sliding rod 7, the spring piece 8, the compression spring 9 and the U-shaped stopper 10, the connection between the housing 101 and the flange 201 is realized. Relatively, the connection between the pneumatic actuator and the valve is realized, and the installation and disassembly between the pneumatic actuator and the valve are made more convenient, which is beneficial to the later maintenance. During installation, rotate the U-shaped stopper 10 to make the U-shaped stopper 10 coaxial with the sliding rod 7, pass the threaded through-hole of the flange 201 through the U-shaped stopper 10 and the sliding rod 7, pull the U-shaped stopper 10 to drive the sliding rod 7 to drive the spring piece 8 to move and drive the compression spring 9 to compress. When the U-shaped stopper 10 completely passes through the threaded through-hole to the lower end of the flange 201, rotate the U-shaped stopper 10 to make it perpendicular to the sliding rod 7. After loosening, the U-shaped stopper 10 perpendicular to the sliding rod 7 closely fits on the bottom end of the flange 201 under the rebounding effect of the compression spring 9, thus realizing the connection between the housing 101 and the flange 201. During disassembly, rotate the U-shaped stopper 10 to make it coaxial with the sliding rod 7, thereby realizing the disconnection of the connection between the housing 101 and the flange 201.

[0031] Specifically, in this embodiment, screw threads 11 are provided on the outer wall of the rotating shaft 3, and a threaded hole 12 is formed in the limiting block 4. The specification of the threaded hole 12 is adapted to that of the screw threads 11, so that the rotation of the rotating shaft 3 realizes the moving effect of the limiting block 4.

[0032] Specifically, in this embodiment, a guide rod 13 is connected between the inner walls of the chamber of the housing 101. The guide rod 13 is parallel to the rotating shaft 3, and the limiting block 4 is slidably connected to the guide rod 13. The guide rod 13 provides stability for the movement of the limiting block 4.

[0033] Specifically, in this embodiment, a knob 14 is connected to each positioning shaft 5. The knob 14 is located outside the housing 101, which is convenient for rotating the rotating shaft 3 from different positions.

[0034] Specifically, in this embodiment, a plurality of positioning bumps 15 are provided at the bottom of the housing 101. The positioning bumps 15 correspond to the positions of the screw through-holes on the flange 201. The sliding rod 7 is slidably connected in the positioning bumps 15, which provides a positioning effect for the installation between the housing 101 and the flange 201 and prevents shaking.

[0035] Specifically, in this embodiment, a first sliding hole 16 is formed in the positioning bump 15. The aperture of the first sliding hole 16 is adapted to the diameter of the sliding rod 7. Second sliding holes 17 are formed on both the positioning bump 15 and the bottom of the housing 101. The aperture of the second sliding hole 17 is adapted to the diameter of the spring piece 8. The compression spring 9 is connected in the second sliding hole 17 and is located at the connection with the first sliding hole 16, which provides a sliding space for the sliding rod 7 and the spring piece 8 and provides a supporting surface for the compression and rebounding of the compression spring 9.

[0036] Specifically, in this embodiment, the length of the open end of the U-shaped stopper 10 from the connection is less than the length of the other end of the U-shaped stopper 10 from the connection. When the U-shaped stopper 10 is perpendicular to the sliding rod 7, both ends can contact the flange 201. At the same time, the length of the open end of the U-shaped stopper 10 is reduced, the compression stroke of the compression spring 9 driven by the sliding rod 7 is reduced, and the operation is more labor-saving.

[0037] The above is only the preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A high-sealing piston pneumatic actuator, comprising an actuator body (1) and a butterfly valve (2), characterized in that: The actuator body (1) is composed of a housing (101), a cover (102), a first piston (103), a second piston (104), a gear (105), an angle adjustment block (106), an angle display assembly (107), a first rack (108), a second rack (109) and a buffer assembly (110). Two rotating shafts (3) are rotatably connected in the housing (101). The two rotating shafts (3) are respectively located on two sides of the angle adjustment block (106). Each rotating shaft (3) is threadedly connected to a limit block (4) on the outer wall of the housing (101). The two limit blocks (4) are located at the same end of the angle adjustment block (106). Positioning shafts (5) are provided at both ends of the two rotating shafts (3). The positioning shafts (5) are rotatably connected in the housing (101). A seal is embedded in the outer wall of each positioning shaft (5). The butterfly valve (2) is composed of a flange (201), a valve body (202), a valve stem (203) and a butterfly plate (204); the valve stem (203) and the gear (105) are connected to each other; the flange (201) and the housing (101) are connected to each other; a plurality of slide bars (7) are slidably connected inside the bottom end of the housing (101); a spring sheet (8) is connected to one end of the slide bar (7) located inside the housing (101); a compression spring (9) is connected between the spring sheet (8) and the housing (101); the slide bar (7) passes through the outer wall of the bottom end of the flange (201) and is rotatably connected to a U-shaped stopper (10); the width of the U-shaped stopper (10) is smaller than the diameter of the screw through hole on the flange (201); and the length of the U-shaped stopper (10) from the connection point to both ends is greater than the radius of the screw through hole on the flange (201).

2. The high-sealing piston pneumatic actuator according to claim 1, characterized in that: The outer wall of the rotating shaft (3) is provided with a screw thread (11), and the limit block (4) is provided with a screw hole (12), and the specifications of the screw hole (12) and the screw thread (11) are adapted.

3. The high-sealing piston pneumatic actuator according to claim 1, characterized in that: A guide rod (13) is connected between the inner walls of the chamber of the housing (101); the guide rod (13) and the rotating shaft (3) are parallel to each other; and the limit block (4) is slidably connected to the guide rod (13).

4. The high-sealing piston pneumatic actuator according to claim 1, characterized in that: Each positioning shaft (5) is connected to a knob (14), and the knob (14) is located outside the housing (101).

5. The high-sealing piston pneumatic actuator according to claim 1, characterized in that: A plurality of positioning protrusions (15) are provided at the bottom of the housing (101), the positioning protrusions (15) corresponding to the positions of the screw holes on the flange (201), and the sliding rods (7) are slidably connected in the positioning protrusions (15).

6. The high-sealing piston pneumatic actuator according to claim 5, characterized in that: A first sliding hole (16) is provided in the positioning protrusion (15), and the diameter of the first sliding hole (16) matches the diameter of the sliding rod (7). A second sliding hole (17) is provided on the bottom of the positioning protrusion (15) and the housing (101), and the diameter of the second sliding hole (17) matches the diameter of the spring sheet (8). The compression spring (9) is connected in the second sliding hole (17) and is located at a position connected to the first sliding hole (16).

7. The high-sealing piston pneumatic actuator according to claim 1, characterized in that: The distance between one end of the notch opening of the U-shaped stopper (10) and the connection is shorter than the distance between the other end of the U-shaped stopper (10) and the connection.

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