Rail-guided pneumatic actuator

Abstract

This invention relates to the field of valve control structure technology and discloses a pneumatic actuator with a guide rail, comprising a cylinder body with end caps installed at both ends, a piston disc inside the cylinder body, a fixed disc inside the cylinder body, multiple guide rods on the fixed disc, the piston disc slidably mounted on the guide rods, a guide rail body at the bottom of the guide rods, a slide rod mounted on the guide rail body, a connecting disc for mounting a connector rotatably mounted inside the cylinder body, a guide rail post on the connecting disc, an inclined groove on the guide rail post, the slide rod slidably mounted in the inclined groove, a bearing on the fixed disc, the inner ring of the bearing being fixedly connected to the connecting disc, a limit block on the inner wall of the guide rail body, and a limit ring on the feedback rod for abutting against the limit block. Rollers on both sides of the guide rail body abut against the inner wall of the inclined groove, ensuring balanced force on both sides of the guide rail body, preventing lateral force from causing one-sided wear of the piston disc, and effectively extending the maintenance cycle of the mechanism.

Description

Technical Field

[0001] This invention relates to the field of valve control structure technology, and more specifically, to a pneumatic actuator with a guide rail. Background Technology

[0002] Pneumatic actuators primarily use compressed air as their power source. Their core structure includes a cylinder, piston or diaphragm, piston rod, spring return assembly, end caps, and seals. Some also include auxiliary components such as solenoid valves, positioners, and limit switches. By using air pressure to drive the diaphragm or piston, the pneumatic energy is converted into linear or rotary mechanical displacement, enabling the opening and closing or regulation of valves and other equipment. Pneumatic actuators are simple in structure, reliable in operation, and respond quickly. They possess explosion-proof and flame-retardant properties, are easy to maintain, and have low costs. They are widely used in industrial automation systems in petroleum, chemical, power, and metallurgical industries. They are mainly used to drive pipeline valves such as regulating valves, ball valves, and butterfly valves to complete the opening and closing of media and flow regulation. They can also be used in automated production lines to perform clamping and pushing actions.

[0003] For example, Chinese patent application CN121429674A discloses a pneumatic drive component and a pneumatic valve. The pneumatic drive component includes a front cover, a rear cover, a cavity, and a piston component. The first end of the cavity is connected to the front cover, and the second end of the cavity is connected to the rear cover. The piston component is disposed in the cavity. The cavity is divided into a first inner cavity corresponding to the front cover and a second inner cavity corresponding to the rear cover based on the piston head of the piston component. The piston component is used to move based on the pressure difference between the first inner cavity and the second inner cavity. The front cover is provided with a first one-way seal, which is used to buffer the movement end of the piston component in a first direction. The rear cover is provided with a second one-way seal, which is used to buffer the movement end of the piston component in a second direction. The first direction is the direction from the rear cover to the front cover, and the second direction is the direction from the front cover to the rear cover. This can buffer the movement end of the piston component in different directions and effectively reduce the impact caused by inertia.

[0004] The normal function of a pneumatic actuator depends heavily on the sealing between the piston and the rigid body. In the aforementioned patents and existing technologies, the piston is guided only by the cylinder, which can easily lead to uneven wear of the piston and one-sided wear of the sealing ring due to lateral forces. After long-term operation, the device requires regular manual maintenance. Therefore, we propose a pneumatic actuator with a guide rail. Summary of the Invention

[0005] This invention provides a pneumatic actuator with a guide rail. This pneumatic actuator can solve the problem mentioned in the background art that the normal function of the pneumatic actuator is highly dependent on the sealing between the piston and the rigid body. In the prior art, the piston is only guided by the cylinder, which easily leads to lateral force causing uneven wear of the piston and one-sided wear of the sealing ring. After long-term operation, the device requires regular manual maintenance.

[0006] To achieve the above objectives, this solution provides a pneumatic actuator with a guide rail, including a cylinder body, end caps installed at both ends of the cylinder body, a piston disc installed inside the cylinder body, a fixed disc installed inside the cylinder body, a plurality of guide rods installed on the fixed disc, the piston disc being slidably mounted on the guide rods, a guide rail body being provided at the bottom of the guide rods, and a sliding rod being installed on the guide rail body; A connecting plate for installing a connector is rotatably mounted inside the cylinder. The connecting plate is provided with a guide rail post, and an inclined groove is opened on the guide rail post. The slide rod is slidably installed in the inclined groove.

[0007] Optionally, a bearing is provided on the fixed disk, and the inner ring of the bearing is fixedly connected to the connecting disk.

[0008] Optionally, a pair of inclined grooves are provided, and the pair of inclined grooves are symmetrically arranged on both sides of the guide rail column. The inclined grooves are configured as spiral grooves, and a roller is rotatably mounted on the slide rod. The roller is rolled in the inclined groove.

[0009] Optionally, a feedback rod is coaxially mounted on the connecting plate, the feedback rod passes through the end cover, and a disc cap is mounted on the top of the feedback rod.

[0010] Optionally, the end cap is provided with a scale, and the cap of the scale is provided with an indicator groove, which is set to correspond to the scale on the scale.

[0011] Optionally, the guide rail body is configured as a sleeve, the inner wall of the guide rail body is provided with a limit block, and a limit ring is installed on the feedback rod for abutting against the limit block. When the feedback rod reaches its maximum stroke, the limit ring abuts against the limit block.

[0012] Optionally, a folded cloth is sealed and installed on the piston disc, a connecting block is provided at the top of the feedback rod, the other end of the folded cloth is sealed and connected to the connecting block, and the natural length of the folded cloth is greater than the one-way stroke of the piston disc; As the piston disc moves downward, the folded fabric unfolds.

[0013] Optionally, the folded fabric has two layers, with the outer layer being a windproof fabric and the inner layer being an elastic fabric. Before the piston disc reaches its maximum stroke, the inner folded fabric is gradually stretched.

[0014] Optionally, the feedback rod is slidably inserted into the connecting block, and a buffer spring is provided at the bottom of the end cap, with the other end of the buffer spring connected to the connecting block.

[0015] Optionally, the folded fabric is detachably connected to the piston disc by screws, and a sealing gasket is provided between the folded fabric and the piston disc, the sealing gasket being a rubber gasket.

[0016] Through the above technical solution, the guide rail-type pneumatic actuator provided by this solution is used as follows: 1. The rollers on both sides of the guide rail body abut against the inner wall of the inclined groove, ensuring that the force on both sides of the guide rail body is balanced, preventing the piston disc from wearing on one side due to lateral force, and effectively extending the maintenance cycle of the mechanism; 2. This mechanism uses folded cloth installed on the piston disc to insulate the feedback rod. When the piston disc moves down, the folded cloth unfolds, and a closed conical space is formed inside the folded cloth, which reduces the impact of the low temperature inside the cylinder on the connection between the piston disc and the feedback rod, and further improves the sealing performance of the piston disc. 3. At the same time, before the piston disc reaches its maximum stroke, the inner folded cloth is gradually stretched, which slows down the piston disc, prevents the impact force between the limit ring and the limit block from being too large, and extends the service life of the limit ring and the limit block.

[0017] Other features and advantages of this solution will be described in detail in the following detailed implementation section. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the following detailed description to explain the present invention, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the internal structure of the cylinder block of the present invention.

[0019] Figure 2 This is a cross-sectional structural diagram of the guide rail post and the guide rail body of the present invention.

[0020] Figure 3 Appendix to this invention Figure 2 A magnified structural diagram of point A in the middle.

[0021] Figure 4 This is an exploded structural diagram of the end cap, fixing plate, guide rail post and guide rail body of the present invention.

[0022] Figure 5 Appendix to this invention Figure 4 A magnified structural diagram at point B in the middle.

[0023] Figure 6 This is a schematic diagram of the installation structure of the feedback rod and connecting plate of the present invention.

[0024] Figure 7 This is a schematic diagram of the structure of the indicator groove and the dial of the present invention.

[0025] Figure 8 This is a schematic diagram of the structure of the buffer spring and folded fabric of the present invention.

[0026] Figure 9 Appendix to this invention Figure 8 A magnified structural diagram at point C.

[0027] Explanation of reference numerals in the attached drawings: 101, cylinder body; 102, end cap; 103, dial; 104, fixed plate; 105, bearing; 201, piston plate; 202, guide rod; 203, guide rail body; 204, roller; 205, limiting block; 206, slide rod; 301, guide rail post; 302, inclined groove; 303, disc cap; 304, indicator groove; 305, feedback rod; 306, connecting plate; 307, limiting ring; 401, folded cloth; 402, sealing gasket; 403, connecting block; 404, buffer spring. Detailed Implementation

[0028] To make the aforementioned objectives, features, and advantages of this solution more apparent and understandable, the specific embodiments of this solution are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this solution. However, this solution can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this solution. Therefore, this solution is not limited to the specific embodiments disclosed below.

[0029] In the description of this solution, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential," etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this solution and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this solution. The terms "first" and "second" are used to distinguish one element from another and do not have sequential or importance. Furthermore, in the following description, when referring to the accompanying drawings, the same reference numerals in different drawings indicate the same or similar elements, which will not be repeated here.

[0030] In this solution, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this solution based on the specific circumstances.

[0031] According to some embodiments of this solution, a guide rail-type pneumatic actuator is provided, as shown in the reference. Figures 1 to 9 As shown, the guide rail type pneumatic actuator includes a cylinder body 101, with end caps 102 installed at both ends of the cylinder body 101. A piston disc 201 is disposed inside the cylinder body 101, and a rubber ring for sealing is disposed around the piston disc 201. A pair of air holes are disposed on the outer wall of the cylinder body 101, and the pair of air holes are respectively located on both sides of the piston disc 201. A fixed disc 104 is installed inside the cylinder body 101, and multiple guide rods 202 are disposed on the fixed disc 104. The piston disc 201 is slidably mounted on the guide rods 202. A guide rail body 203 is disposed at the bottom of the guide rod 202, and a slide rod 206 is mounted on the guide rail body 203. A connecting disc 306 for installing a connector is rotatably mounted inside the cylinder body 101. A guide rail post 301 is disposed on the connecting disc 306, and an inclined groove 302 is opened on the guide rail post 301. The slide rod 206 is slidably mounted in the inclined groove 302.

[0032] Thus, when this mechanism is in use, the connector at the bottom of the piston disc 201 engages and is fixed with the switch block of the ball valve, butterfly valve, and various 90° actuating products. Compressed gas enters the cylinder 101 from one of the air holes (taking the upper air hole as an example), causing the pressure above the piston disc 201 to increase. The piston disc 201 moves along multiple guide rods 202. The piston disc 201 drives the guide rail body 203 and slide rod 206 to move down synchronously. When the slide rod 206 slides in the inclined groove 302, the guide rail column 301 drives the connecting disc 306 to rotate, thereby realizing the opening and closing of the valve and various 90° actuating products.

[0033] For details, please refer to Figure 2 A bearing 105 is provided on the fixed plate 104, and the inner ring of the bearing 105 is fixedly connected to the connecting plate 306.

[0034] The inclined groove 302 is provided in a pair and is symmetrically arranged on both sides of the guide rail post 301. The inclined groove 302 is a spiral groove. A roller 204 is rotatably installed on the slide rod 206. The roller 204 is rolled in the inclined groove 302. The rollers 204 on both sides of the guide rail body 203 abut against the inner wall of the inclined groove 302 respectively to ensure that the force on both sides of the guide rail body 203 is balanced and to prevent the piston disc 201 above the guide rail body 203 from wearing out due to uneven force.

[0035] In addition, a feedback rod 305 is coaxially mounted on the connecting plate 306. The feedback rod 305 passes through the end cover 102, and a disc cap 303 is installed on the top of the feedback rod 305. Therefore, the feedback rod 305 can rotate synchronously with the connecting plate 306. By observing the deflection of the disc cap 303 at the top of the feedback rod 305, it is possible to further determine whether the rotation of the connecting plate 306 is normal, which is beneficial for subsequent maintenance.

[0036] For further details, please refer to... Figure 6 , Figure 7 The end cap 102 is provided with a dial 103, and the dial cap 303 is provided with an indicator groove 304, which is set to correspond to the scale on the dial 103.

[0037] Additionally, please refer to Figure 2 The guide rail body 203 is configured as a sleeve, and a limit block 205 is provided on the inner wall of the guide rail body 203. A limit ring 307 is installed on the feedback rod 305 for abutting against the limit block 205. When the feedback rod 305 reaches its maximum stroke, the limit ring 307 abuts against the limit block 205.

[0038] Through the above technical solution, the pneumatic actuator with guide rail provided by this solution, when in use, compressed gas enters the cylinder 101 from one of the air holes, causing an increase in pressure on one side of the piston disc 201. The piston disc 201 moves along multiple guide rods 202, and the piston disc 201 drives the guide rail body 203, slide rod 206, and roller 204 to move downwards synchronously. When the roller 204 slides in the inclined groove 302, the guide rail column 301 drives the connecting plate 306 to rotate, and the rollers 204 on both sides of the guide rail body 203 respectively... The contact with the inner wall of the inclined groove 302 ensures that the force on both sides of the guide rail body 203 is balanced, preventing the piston disc 201 from wearing on one side due to lateral force. This effectively extends the maintenance cycle of the mechanism and solves the problem mentioned in the background technology that the normal function of the pneumatic actuator is highly dependent on the sealing between the piston and the rigid body. In the prior art, the piston disc 201 is only guided by the cylinder body 101, which easily leads to uneven wear of the piston and one-sided wear of the sealing ring due to lateral force. After long-term operation, the device requires regular manual maintenance.

[0039] It should be noted that in the existing technology, the compressed gas used in pneumatic actuators mainly comes from a centralized compressed air supply system. The core system consists of an air compressor, an air tank, a drying and purification device, and a pipeline transportation network. Atmosphere is drawn in by the air compressor and compressed to form compressed air. It then enters the air tank for buffering and stabilizing, while separating moisture and impurities. To ensure the stable operation of the actuator, the compressed air also needs to be purified by filters and dryers to remove oil, dust, and liquid water, so as to avoid corrosion of internal parts or blockage of the air passage. The purified and dry clean gas is transported to each air-using point through the plant pipeline network. After being adjusted to a suitable working pressure by a pressure reducing valve, it is connected to the air inlet of the pneumatic actuator. Among them, the cylinder 101 has two types of air intake methods: single-acting air intake and double-acting air intake. In the single-acting air intake method, the cylinder 101 has only one air intake port. Compressed air enters the cylinder 101 through the single air intake port, pushing the piston disc 201 to move and realize valve opening or adjustment. When the air is cut off, the piston disc 201 inside the cylinder 101 automatically returns to the initial safe position by relying on the elastic force of the return spring. It is suitable for scenarios where safety reset is required. In addition, in the dual-acting intake mode, the cylinder block 101 is equipped with two intake ports and has no return spring. The core structure is the bidirectional piston disc 201. The working principle is to alternately intake and exhaust through the two intake ports. When one side is intake, the other side is exhaust, which pushes the piston disc 201 to move in both directions, thereby driving the actuator to complete forward and reverse actions. When the air supply is cut off, the piston disc 201 remains in its current position. Its output force and action speed are better, making it suitable for scenarios with high power and response requirements. In this embodiment, the cylinder 101 adopts a double-acting intake method. In specific implementation, if a single-acting intake method is required, a return spring can be sleeved on the feedback rod 305. One end of the return spring is connected to the piston disc 201, and the other end of the return spring is connected to the end cover 102 or the fixed disc 104. Additionally, in this embodiment, please refer to Figure 2 The bottom of the connecting plate 306 is equipped with an internal hexagonal adapter, which is engaged and fixed with the valve switch block. In specific implementation, the connecting plate 306 and the valve switch can also be connected by a flange. Specifically, flanges are provided at the bottom of the connecting plate 306 and on the valve switch, and the two flanges are fixedly connected by bolts to realize the transmission between the connecting plate 306 and the valve switch.

[0040] In some implementations of this solution, reference is made to Figure 2 , Figure 3As shown, a folded cloth 401 is sealed and installed on the piston disc 201, and a connecting block 403 is provided on the top of the feedback rod 305. The other end of the folded cloth 401 is sealed and connected to the connecting block 403. The natural length of the folded cloth 401 is greater than the one-way stroke of the piston disc 201. When the piston disc 201 moves down, the folded cloth 401 unfolds.

[0041] It should be noted that after the compressed gas enters the cylinder 101 through the air inlet, it expands and absorbs heat, causing the internal temperature of the cylinder 101 to drop. If the gas inside the cylinder 101 cannot exchange heat with the outside air in time through the cylinder 101, the internal structure temperature of the cylinder 101 will decrease and contract to varying degrees, affecting the sealing performance between the piston disc 201 and the feedback rod 305. Therefore, this mechanism uses a folded cloth 401 installed on the piston disc 201 to insulate the feedback rod 305. When the piston disc 201 moves down, the folded cloth 401 unfolds, and a closed conical space is formed inside the folded cloth 401, reducing the impact of the low temperature inside the cylinder 101 on the connection between the piston disc 201 and the feedback rod 305.

[0042] Specifically, during the unfolding of the folded cloth 401, the low-temperature gas inside the cylinder 101 exchanges heat with the outside air through the cylinder 101. The low-temperature gas inside the cylinder 101 does not come into direct contact with the feedback rod 305, preventing the feedback rod 305 from contracting due to a sudden drop in temperature. This ensures the sealing performance of the connection between the piston disc 201 and the feedback rod 305, further making the downward movement of the piston disc 201 and the rotation of the connecting disc 306 more precise.

[0043] Specifically, the folded cloth 401 has two layers. The outer folded cloth 401 is a windproof cloth (nylon cloth, polyester cloth, etc.), and the inner folded cloth 401 is an elastic cloth (thermoplastic polyurethane, etc.). Before the piston disc 201 reaches its maximum stroke, the inner folded cloth 401 is gradually stretched.

[0044] It should be noted that in this embodiment, the piston disc 201 is braked by the impact and contact between the limiting ring 307 and the limiting block 205. After long-term operation, the limiting ring 307 and the limiting block 205 will experience varying degrees of wear, which will affect their mechanical properties. Therefore, before the piston disc 201 reaches its maximum stroke, the inner folded cloth 401 is gradually stretched to decelerate the piston disc 201, prevent the impact force between the limiting ring 307 and the limiting block 205 from being too large, and extend the service life of the limiting ring 307 and the limiting block 205.

[0045] Furthermore, the feedback rod 305 is slidably inserted into the connecting block 403, and a buffer spring 404 is provided at the bottom of the end cover 102, with the other end of the buffer spring 404 connected to the connecting block 403.

[0046] Specifically, the folded cloth 401 is detachably connected to the piston disc 201 by screws, and a sealing gasket 402 is provided between the folded cloth 401 and the piston disc 201. The sealing gasket 402 is a rubber gasket.

[0047] It should be noted that in this mechanism, the folded cloth 401 is used to insulate the feedback rod 305. Similarly, in specific implementation, the same folded cloth 401 can also be set around the slide rod 206.

[0048] The preferred embodiments of this solution have been described in detail above with reference to the accompanying drawings. However, this solution is not limited to the specific details in the above embodiments. Within the scope of the technical concept of this solution, various simple modifications can be made to the technical solution, and these simple modifications all fall within the protection scope of this solution.

[0049] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable way without contradiction. In order to avoid unnecessary repetition, this solution will not describe the various possible combinations separately.

[0050] Furthermore, various implementations of this solution can be combined in any way, as long as they do not violate the spirit of this solution, they should also be regarded as the content disclosed in this solution.

Claims

1. A pneumatic actuator with guide rail, comprising a cylinder body (101), wherein end caps (102) are respectively installed at both ends of the cylinder body (101), and a piston disc (201) is disposed inside the cylinder body (101), characterized in that: The cylinder body (101) is equipped with a fixed plate (104), and a plurality of guide rods (202) are provided on the fixed plate (104). The piston plate (201) is slidably mounted on the guide rods (202). A guide rail body (203) is provided at the bottom of the guide rod (202), and a slide rod (206) is installed on the guide rail body (203). The cylinder body (101) is rotatably mounted with a connecting plate (306) for installing a connector. The connecting plate (306) is provided with a guide post (301). The guide post (301) is provided with an inclined groove (302). The slide rod (206) is slidably installed in the inclined groove (302).

2. The pneumatic actuator with guide rail according to claim 1, characterized in that: A bearing (105) is provided on the fixed disk (104), and the inner ring of the bearing (105) is fixedly connected to the connecting disk (306).

3. The pneumatic actuator with guide rail according to claim 1, characterized in that: A pair of inclined grooves (302) are provided, and the pair of inclined grooves (302) are symmetrically arranged on both sides of the guide rail column (301). The inclined grooves (302) are spiral grooves. A roller (204) is rotatably installed on the slide rod (206). The roller (204) is rolled in the inclined groove (302).

4. A pneumatic actuator with guide rail according to claim 1, characterized in that: A feedback rod (305) is coaxially mounted on the connecting plate (306), the feedback rod (305) passes through the end cover (102), and a disc cap (303) is mounted on the top of the feedback rod (305).

5. A pneumatic actuator with guide rail according to claim 4, characterized in that: The end cap (102) is provided with a dial (103), and the dial cap (303) is provided with an indicator groove (304), which is set to correspond to the scale on the dial (103).

6. A pneumatic actuator with guide rail according to claim 4, characterized in that: The guide rail body (203) is configured as a sleeve, and a limit block (205) is provided on the inner wall of the guide rail body (203). A limit ring (307) is installed on the feedback rod (305) for abutting against the limit block (205). When the feedback rod (305) reaches its maximum stroke, the limit ring (307) abuts against the limit block (205).

7. A pneumatic actuator with guide rail according to claim 4, characterized in that: A folded cloth (401) is sealed and installed on the piston disc (201), and a connecting block (403) is provided on the top of the feedback rod (305). The other end of the folded cloth (401) is sealed and connected to the connecting block (403). The natural length of the folded cloth (401) is greater than the one-way stroke of the piston disc (201). When the piston disc (201) moves downward, the folded cloth (401) unfolds.

8. A pneumatic actuator with guide rail according to claim 7, characterized in that: The folded fabric (401) has two layers, with the outer layer being a windproof fabric and the inner layer being an elastic fabric. Before the piston disc (201) reaches its maximum stroke, the inner folded fabric (401) is gradually stretched.

9. A pneumatic actuator with guide rail according to claim 7, characterized in that: The feedback rod (305) is slidably inserted into the connecting block (403), and a buffer spring (404) is provided at the bottom of the end cap (102), with the other end of the buffer spring (404) connected to the connecting block (403).

10. A pneumatic actuator with guide rail according to claim 7, characterized in that: The folded cloth (401) is detachably connected to the piston disc (201) by screws, and a sealing gasket (402) is provided between the folded cloth (401) and the piston disc (201), and the sealing gasket (402) is a rubber gasket.

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