Pneumatic execution device

Abstract

The utility model discloses a pneumatic execution device which is internally provided with a first limiting protection assembly and a second limiting protection assembly, when a piston body in the pneumatic execution device runs to an opening limiting position and a closing limiting position, elastic buffering elements are introduced respectively, rigid collision is converted into a controllable elastic buffering process, and therefore the peak value of impact force is remarkably reduced, and the service life of the pneumatic execution device is prolonged. Precise parts in the pneumatic execution device and an end cover connected with the precise parts are prevented from being damaged, and finally the reliability and the service life of the system are improved.

Description

Technical Field

[0001] This utility model relates to the field of pneumatic actuator technology, and in particular to a pneumatic actuator device suitable for valve control scenarios that require rapid opening and closing. Background Technology

[0002] In the field of modern industrial automation control, especially in situations requiring rapid response and emergency shut-off, the demands on the switching speed of valve actuators are increasing. Many critical applications require valves to achieve full-stroke action in extremely short times, such as opening or closing within 3 seconds or even less than 1 second. This high-speed action is crucial for ensuring process safety, reducing process fluctuations, or meeting specific process requirements.

[0003] However, the high-speed operation of valve actuators also presents significant challenges. When a valve rapidly moves to its fully open or fully closed extreme position, the piston and its rigidly connected push shaft carry enormous kinetic energy and impact the end cover of the actuator. This rigid impact at high speed generates a strong instantaneous impact force, which not only damages critical components inside the pneumatic actuator, such as the piston, push shaft, end cover, and seals (causing deformation, wear, or even breakage), but also transmits the impact force to the valve body through the push shaft, leading to damage to precision components such as the valve core, valve seat, and valve stem. Long-term operation under such high impact loads will significantly shorten the service life of the actuator, increase maintenance costs and downtime risks, and more seriously, may cause safety hazards due to sudden failure of critical components, affecting the safe and reliable operation of the entire system.

[0004] Current common solutions often focus on increasing the rigidity and strength of the actuator itself to withstand impacts, or on installing buffer structures at the valve end. However, this often increases the complexity and cost of the system, and has limited protection for the moving parts inside the actuator, especially in effectively dispersing and absorbing the huge impact energy generated at the high-speed moving end.

[0005] In view of the problems existing in the above-mentioned technologies, especially the component damage and safety hazards caused by the impact at the end of the high-speed actuator, there is an urgent need for a protective device that can be directly integrated into the actuator and effectively absorb the impact energy at the end of the high-speed motion. Utility Model Content

[0006] The purpose of this utility model is to provide a pneumatic actuator with built-in first and second limit protection components. By introducing elastic buffer elements when the piston inside the pneumatic actuator runs to the two extreme positions of opening and closing, the rigid collision is transformed into a controllable elastic buffering process, thereby significantly reducing the peak impact force and protecting the precision components inside the pneumatic actuator and the end caps connected to them from damage, ultimately improving the reliability and service life of the system.

[0007] To achieve the above objective, a pneumatic actuator includes:

[0008] The cylinder body includes a first end cap and a second end cap, wherein a first through hole is provided in the middle of the first end cap;

[0009] A piston body is disposed inside the cylinder and is sealed to the inner wall of the cylinder, and the piston body is axially movable along the inner wall of the cylinder.

[0010] A push shaft, one end of which is connected to the middle of the piston body, and the other end of which extends out of the cylinder body through the first through hole. The push shaft is sealed to the inner wall of the first through hole, and the piston body can drive the push shaft to move along the axial direction of the cylinder body.

[0011] A first limiting protection component is provided with a second through hole in the middle for the push shaft to pass through; the first limiting protection component is disposed in the middle of the inner wall of the first end cover, and a part of the push shaft passes through the second through hole;

[0012] The first limiting protection component includes a first connecting seat, a receiving ring, and an elastic ring. The interior of the first connecting seat is hollow to form a receiving cavity. The receiving ring and the elastic ring are stacked in the receiving cavity. One end of the push shaft protrudes from the end near the piston body and is provided with an abutting part. The abutting part can pass through the second through hole and abut against the receiving ring.

[0013] The second limiting protection component is disposed in the middle of the inner wall of the second end cover. The second limiting protection component includes an elastic contact end, which corresponds to the end of the push shaft near the second end cover, so that when the end of the push shaft moves to the elastic contact end, the elastic contact end can be abutted by the end of the push shaft and elastically contract when abutted.

[0014] Furthermore, as a more preferred embodiment of this utility model, the second limiting protection component includes:

[0015] The second connecting seat is hollow inside, and a through groove is provided at the end of the second connecting seat. The through groove can accommodate the end of the push shaft to be inserted into the interior of the second connecting seat; a limiting ring portion protruding inward is provided at the port of the through groove.

[0016] A pressure-bearing plate is disposed within the second connecting seat and is capable of sliding along the inner wall of the second connecting seat;

[0017] An elastic element is disposed within the second connecting seat, and the elastic force of the elastic element can push the pressure plate toward the through groove, so that the outer wall of the pressure plate abuts against the limiting ring.

[0018] Furthermore, as a more preferred embodiment of the present invention, a first magnetic ring is provided at the end of the first connecting seat, and a second magnetic ring is provided at the end of the piston body opposite to the first connecting seat. The first magnetic ring and the second magnetic ring are adapted to each other, and the magnetic properties of the first magnetic ring and the second magnetic ring are repulsive.

[0019] Furthermore, as a more preferred embodiment of the present invention, a third magnetic ring is provided at the end of the second connecting seat, and a fourth magnetic ring is provided at the end of the piston body opposite to the second connecting seat, wherein the third magnetic ring and the fourth magnetic ring are adapted to each other.

[0020] Furthermore, as a more preferred embodiment of the present invention, a third through hole is provided in the middle of the piston body for the push shaft to pass through, one end of the push shaft passes through the third through hole, the abutting part abuts against one end of the third through hole, and the end of the push shaft is pre-tightened and fixed to the piston body by a nut, so that the piston body is clamped between the abutting part and the nut.

[0021] Furthermore, as a more preferred embodiment of this utility model, the cylinder body includes:

[0022] A cylinder barrel, wherein the two ends of the cylinder barrel are respectively sealed to a first end cap and a second end cap, and the outer diameters of the first end cap and the second end cap are larger than the outer diameter of the cylinder barrel;

[0023] A plurality of screws are provided, and the first end cap and the second end cap are connected by the plurality of screws, such that the first end cap and the second end cap clamp the cylinder, and the plurality of screws are located on the outer periphery of the cylinder.

[0024] Furthermore, as a more preferred embodiment of the present invention, at least one first air nozzle is provided on the first end cap, and at least one second air nozzle is provided on the second end cap. The first air nozzle and the second air nozzle are respectively used to connect to the air pressure output device.

[0025] Furthermore, as a more preferred embodiment of this utility model, the inner ring of the first through hole is provided with at least one first annular groove, and a first sealing ring is installed in the at least one first annular groove. The first sealing ring is used to achieve a sealed connection with the push shaft; the inner ring of the third through hole is provided with at least one second annular groove, and a second sealing ring is installed in the at least one second annular groove. The second sealing ring is used to achieve a sealed connection with the piston body.

[0026] Furthermore, as a more preferred embodiment of this utility model, the accommodating cavity is recessed in a stepped shape in the middle of the first through hole, so that the elastic force of the elastic ring can press the outer periphery of the receiving ring against the stepped inner wall of the accommodating cavity near the first through hole, thereby preventing the receiving ring from falling out.

[0027] Furthermore, as a more preferred embodiment of this utility model, the outer ring of the first connecting seat is provided with a stepped portion, and the stepped portion is detachably connected to the first end cover by a plurality of screws.

[0028] The beneficial effects of this utility model are: at the two extreme positions of the pneumatic actuator, the impact energy is absorbed by the elastic ring and elastic element respectively, reducing the peak impact force and effectively preventing component damage. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below.

[0030] Figure 1 This is a half-section structural diagram of the pneumatic actuator in this embodiment.

[0031] Figure 2 This is a three-dimensional structural diagram of the pneumatic actuator in this embodiment.

[0032] Figure 3 This is an exploded view of the pneumatic actuator in this embodiment.

[0033] Figure label:

[0034] 100-Cylinder block; 110-First end cap; 111-First through hole; 112-First valve stem; 120-Second end cap; 121-Second valve stem; 130-Cylinder barrel; 140-Screw;

[0035] 200 - Piston body; 210 - Third through hole; 220 - Second magnetic ring; 230 - Fourth magnetic ring;

[0036] 300 - Push shaft; 310 - Abutment part; 320 - Nut;

[0037] 400 - First limit protection component; 410 - First connecting seat; 411 - Receiving cavity; 420 - Receiving ring; 430 - Elastic ring body; 440 - First magnetic ring;

[0038] 500 - Second limit protection component; 510 - Second connecting seat; 511 - Through groove; 512 - Limiting ring; 520 - Pressure plate; 530 - Elastic element; 540 - Third magnetic ring. Detailed Implementation

[0039] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0040] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly set on the other component; when a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to the other component.

[0041] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0042] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" or "several" means two or more, unless otherwise explicitly specified.

[0043] It should be noted that the structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size should still fall within the scope of the technical content disclosed in this application, provided that they do not affect the effects and purposes that this application can produce.

[0044] Example

[0045] This embodiment aims to address the significant impact forces generated by pneumatic actuators at their open and closed extreme positions in existing technologies, particularly the impact at the end of high-speed actuators, which leads to component damage and safety hazards. Therefore, referring to... Figure 1-3As shown, this embodiment provides a pneumatic actuator with built-in first and second limit protection components 500. By introducing elastic buffer elements when the piston body 200 inside the pneumatic actuator runs to the two extreme positions of opening and closing, the rigid collision is transformed into a controllable elastic buffering process, thereby significantly reducing the peak impact force. The precision components inside the pneumatic actuator and the end cap connected thereto are protected from damage, ultimately improving the reliability and service life of the system.

[0046] Reference Figure 1-3 As shown, a pneumatic actuator includes a cylinder body 100, a piston body 200, a push shaft 300, a first limit protection component 400, and a second limit protection component 500. The cylinder body 100 includes a first end cap 110 and a second end cap 120, with a first through hole 111 located in the center of the first end cap 110.

[0047] The piston body 200 is disposed inside the cylinder body 100 and is sealed to the inner wall of the cylinder body 100, and the piston body 200 is axially movable along the inner wall of the cylinder body 100. For example, the piston body 200 may be a circular plate with a groove on its outer periphery for assembling a double-lip sealing ring, and then installed inside the cylinder 130.

[0048] One end of the push shaft 300 is connected to the middle of the piston body 200, and the other end of the push shaft 300 extends out of the cylinder body 100 through the first through hole 111. The push shaft 300 is sealed to the inner wall of the first through hole 111, and the piston body 200 can drive the push shaft 300 to move along the axial direction of the cylinder body 100.

[0049] The first limiting protection component 400 has a second through hole in its middle for the push shaft 300 to pass through; the first limiting protection component 400 is disposed in the middle of the inner wall of the first end cover 110, and a part of the push shaft 300 passes through the second through hole; the first limiting protection component 400 includes a first connecting seat 410, a receiving ring 420, and an elastic ring 430. The interior of the first connecting seat 410 is hollow to form a receiving cavity 411. The receiving ring 420 and the elastic ring 430 are stacked in the receiving cavity 411. One end of the push shaft 300, near the piston body 200, protrudes and has an abutment portion 310. The abutment portion 310 can pass through the second through hole and abut against the receiving ring 420. The elastic ring 430 can be a disc spring ring or a spring.

[0050] The second limiting protection component 500 is disposed in the middle of the inner wall of the second end cover 120. The second limiting protection component 500 includes an elastic contact end, which corresponds to the end position of the push shaft 300 near the second end cover 120, so that when the end of the push shaft 300 moves to the elastic contact end, the elastic contact end can be abutted by the end of the push shaft 300 and elastically contract when abutting.

[0051] Reference Figure 1-3 As shown, in some embodiments, the second limiting protection component 500 includes: a second connecting seat 510, a pressure-bearing plate 520, and an elastic member 530. The second connecting seat 510 is hollow inside, and its end is provided with a through groove 511, which can accommodate the end of the push shaft 300 inserted into the interior of the second connecting seat 510; the port of the through groove 511 is provided with a limiting ring portion 512 protruding inwards.

[0052] The pressure plate 520 is disposed within the second connecting seat 510 and is capable of sliding along the inner wall of the second connecting seat 510.

[0053] The elastic element 530 is disposed within the second connecting seat 510, and the elastic force of the elastic element 530 can push the pressure plate 520 toward the through groove 511, so that the outer wall of the pressure plate 520 abuts against the limiting ring portion 512. For example, the elastic element 530 can be a disc spring or a spring.

[0054] Reference Figure 1-3 As shown, in some embodiments, a first magnetic ring 440 is provided at the end of the first connecting seat 410, and a second magnetic ring is provided at the end of the piston body 200 opposite to the first connecting seat 410. The first magnetic ring 440 and the second magnetic ring are adapted to each other, and the magnetic properties of the first magnetic ring 440 and the second magnetic ring are repulsive.

[0055] Reference Figure 1-3 As shown, in some embodiments, a third magnetic ring 540 is provided at the end of the second connecting seat 510, and a fourth magnetic ring 230 is provided at the end of the piston body 200 opposite to the second connecting seat 510, and the third magnetic ring 540 and the fourth magnetic ring 230 are adapted to each other.

[0056] In some embodiments, a third through hole 210 is provided in the middle of the piston body 200 for the push shaft 300 to pass through. One end of the push shaft 300 passes through the third through hole 210, and the abutting part 310 abuts against one end of the third through hole 210. The end of the push shaft 300 is pre-tightened and fixed to the piston body 200 by a nut 320, so that the piston body 200 is clamped between the abutting part 310 and the nut 320.

[0057] Reference Figure 1-3As shown, in some embodiments, the cylinder body 100 includes a cylinder barrel 130 and a plurality of screws 140. The two ends of the cylinder barrel 130 are respectively sealed to a first end cap 110 and a second end cap 120, and the outer diameters of the first end cap 110 and the second end cap 120 are larger than the outer diameter of the cylinder barrel 130. The first end cap 110 and the second end cap 120 are connected by a plurality of screws 140, so that the first end cap 110 and the second end cap 120 clamp the cylinder barrel 130, and the plurality of screws 140 are located on the outer periphery of the cylinder barrel 130. It should be added that both the first end cap 110 and the second end cap 120 are provided with bosses adapted to the cylinder body 100. The bosses are inserted into the cylinder body 100 to achieve positioning and limited movement. The outer edge of the boss is recessed to accommodate a sealing ring. The sealing ring is used to seal the gap between the first end cap 110 and the second end cap 120 and the cylinder barrel 130, thus providing a sealing function.

[0058] Reference Figure 1-3 As shown, in some embodiments, at least one first air nozzle 112 is provided on the first end cap 110, and at least one second air nozzle 121 is provided on the second end cap 120. The first air nozzle 112 and the second air nozzle 121 are respectively used to connect to the air pressure output device.

[0059] In some embodiments, the inner ring of the first through hole 111 is provided with at least one first annular groove, and a first sealing ring is installed in the at least one first annular groove. The first sealing ring is used to achieve a sealing connection with the push shaft 300; the inner ring of the third through hole 210 is provided with at least one second annular groove, and a second sealing ring is installed in the at least one second annular groove. The second sealing ring is used to achieve a sealing connection with the piston body 200.

[0060] Reference Figure 1-3 As shown, in some embodiments, the receiving cavity 411 is recessed in the middle of the first through hole 111 in a stepped shape, so that the elastic force of the elastic ring 430 can press the outer periphery of the receiving ring 420 against the stepped inner wall of the receiving cavity 411 near the first through hole 111, thereby preventing the receiving ring 420 from falling out.

[0061] Reference Figure 1-3 As shown, in some embodiments, the outer ring of the first connecting seat 410 is provided with a stepped portion, which is detachably connected to the first end cover 110 by a plurality of screws 140.

[0062] Reference Figure 1-3As shown, it should be noted that during the extension process of the push shaft 300, high-pressure gas pushes the piston body 200 downward through the second air nozzle 121, that is, towards the first end cover 110. When the piston body 200 approaches the first end cover 110: the first magnetic ring 440 and the second magnetic ring 220 generate a repulsive force, slowing down the speed of the piston body 200; the abutment part 310 passes through the second through hole and impacts the receiving ring 420; the elastic ring 430 is compressed and deformed, absorbing the remaining kinetic energy. It should be noted that when the elastic ring 430 is compressed and deformed to its end point, the piston body 200 stops at a limit. At this time, there is still a certain gap between the first magnetic ring 440 and the second magnetic ring 220 to avoid collision between them.

[0063] During the retraction process of the push shaft 300, high-pressure gas pushes the piston body 200 upward through the first air nozzle 112, i.e., towards the second end cover 120. When it approaches the second end cover 120: the third magnetic ring 540 and the fourth magnetic ring 230 generate a repulsive force, slowing down the piston body 200 and reducing the impact. The end of the push shaft impacts the pressure plate 520; the elastic element 530 is compressed. If the elastic element 530 can be a disc-shaped double spring assembly, it absorbs the remaining kinetic energy.

[0064] This embodiment employs a bidirectional elastic buffer: at the two extreme positions of opening and closing, the impact energy is absorbed by the elastic ring 430 and the elastic element 530 respectively, reducing the peak impact force and effectively preventing component damage.

[0065] This embodiment employs magnetically assisted buffering: the repulsive force of the magnetic rings slows down the approach speed of the piston body 200; modular integrated design: the buffer assembly is built-in and detachably connected to the end cap, without increasing the complexity of the external structure, making maintenance convenient; high reliability: the stepped accommodating cavity, limiting ring, and other designs prevent the buffer components from shifting and failing, adapting to high-frequency, rapid opening and closing conditions. Significant safety benefits: if this embodiment is applied to the pneumatic actuator of an emergency shut-off valve in a chemical plant, it extends the life of the actuator and the valve, reducing the risk of failure in the emergency shut-off system.

[0066] The device provided in the embodiments of this application has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only for the purpose of helping to understand this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A pneumatic actuator, characterized in that, include: The cylinder body includes a first end cap and a second end cap, wherein a first through hole is provided in the middle of the first end cap; A piston body is disposed inside the cylinder and is sealed to the inner wall of the cylinder, and the piston body is axially movable along the inner wall of the cylinder. A push shaft, one end of which is connected to the middle of the piston body, and the other end of which extends out of the cylinder body through the first through hole. The push shaft is sealed to the inner wall of the first through hole, and the piston body can drive the push shaft to move along the axial direction of the cylinder body. A first limiting protection component is provided with a second through hole in the middle for the push shaft to pass through; the first limiting protection component is disposed in the middle of the inner wall of the first end cover, and a part of the push shaft passes through the second through hole; The first limiting protection component includes a first connecting seat, a receiving ring, and an elastic ring. The interior of the first connecting seat is hollow to form a receiving cavity. The receiving ring and the elastic ring are stacked in the receiving cavity. One end of the push shaft protrudes from the end near the piston body and is provided with an abutting part. The abutting part can pass through the second through hole and abut against the receiving ring. The second limiting protection component is disposed in the middle of the inner wall of the second end cover. The second limiting protection component includes an elastic contact end, which corresponds to the end of the push shaft near the second end cover, so that when the end of the push shaft moves to the elastic contact end, the elastic contact end can be abutted by the end of the push shaft and elastically contract when abutted.

2. The pneumatic actuator according to claim 1, characterized in that, The second limit protection component includes: The second connecting seat is hollow inside, and a through groove is provided at the end of the second connecting seat. The through groove can accommodate the end of the push shaft to be inserted into the interior of the second connecting seat; a limiting ring portion protruding inward is provided at the port of the through groove. A pressure-bearing plate is disposed within the second connecting seat and is capable of sliding along the inner wall of the second connecting seat; An elastic element is disposed within the second connecting seat, and the elastic force of the elastic element can push the pressure plate toward the through groove, so that the outer wall of the pressure plate abuts against the limiting ring.

3. The pneumatic actuator according to claim 1, characterized in that, The first connecting seat is provided with a first magnetic ring at one end, and the piston body is provided with a second magnetic ring at the end opposite to the first connecting seat. The first magnetic ring and the second magnetic ring are adapted to each other, and the magnetic properties of the first magnetic ring and the second magnetic ring are repulsive.

4. The pneumatic actuator according to claim 2, characterized in that, The end of the second connecting seat is provided with a third magnetic ring, and the end of the piston body opposite to the second connecting seat is provided with a fourth magnetic ring, the third magnetic ring and the fourth magnetic ring being adapted to each other.

5. The pneumatic actuator according to claim 1, characterized in that, The piston body has a third through hole in the middle for the push shaft to pass through. One end of the push shaft passes through the third through hole. The abutting part abuts against one end of the third through hole. The end of the push shaft is pre-tightened to the piston body by a nut so that the piston body is clamped between the abutting part and the nut.

6. The pneumatic actuator according to claim 1, characterized in that, The cylinder body includes: A cylinder barrel, wherein the two ends of the cylinder barrel are respectively sealed to a first end cap and a second end cap, and the outer diameters of the first end cap and the second end cap are larger than the outer diameter of the cylinder barrel; A plurality of screws are provided, and the first end cap and the second end cap are connected by the plurality of screws, such that the first end cap and the second end cap clamp the cylinder, and the plurality of screws are located on the outer periphery of the cylinder.

7. The pneumatic actuator according to claim 6, characterized in that, The first end cap has at least one first air nozzle, and the second end cap has at least one second air nozzle. The first air nozzle and the second air nozzle are respectively used to connect to the air pressure output device.

8. The pneumatic actuator according to claim 5, characterized in that, The inner ring of the first through hole is provided with at least one first annular groove, and a first sealing ring is installed in the at least one first annular groove. The first sealing ring is used to achieve a sealing connection with the push shaft. The inner ring of the third through hole is provided with at least one second annular groove, and a second sealing ring is installed in the at least one second annular groove. The second sealing ring is used to achieve a sealing connection with the piston body.

9. The pneumatic actuator according to claim 1, characterized in that, The accommodating cavity is recessed in a stepped shape in the middle of the first through hole, so that the elastic force of the elastic ring can press the outer periphery of the receiving ring against the stepped inner wall of the accommodating cavity near the first through hole, thereby preventing the receiving ring from falling out.

10. The pneumatic actuator according to claim 1, characterized in that, The outer ring of the first connecting seat is provided with a stepped portion, which is detachably connected to the first end cover by a plurality of screws.

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