Double-acting pneumatic actuator

Abstract

The invention relates to a double-acting pneumatic actuator which comprises an air cylinder module comprising a cylinder body assembly and a piston assembly, and the piston assembly is sequentially provided with a sealing component and a wear-resistant belt in the radial direction of the cylinder body assembly; the box body module is provided with a first end and a second end, the first end and the second end are each provided with an air cylinder module, a guide assembly and a shifting fork assembly are arranged in the box body module, and the guide assembly is used for guiding the piston assembly to move in the axial direction of the cylinder body assembly; the shifting fork assembly is used for being connected with a valve rotating shaft and converting linear motion of the piston assembly into rotating motion of the valve rotating shaft. The sealing mode of the sealing component and the wear-resistant belt is adopted on the piston assembly, the sealing component is in contact sealing with the wear-resistant belt, and the wear-resistant belt is in friction contact with the inner wall of the air cylinder for sealing, so that the service life of the sealing component can be effectively prolonged. The piston assembly operates more stably through the guide assembly, linear motion of the piston assembly is converted into rotation motion of the valve rotating shaft through the shifting fork assembly, and therefore opening and closing control over the valve is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of pneumatic actuators, in particular to a double-acting pneumatic actuator. Background Art

[0002] Pneumatic actuators are control actuators for opening and closing valves. Their structure generally includes an actuator housing and cylinders arranged on both sides of the actuator housing. The cylinders are provided with air inlets and exhaust ports. The pistons in the two cylinders are connected by a piston rod that passes through the actuator housing. When the piston and the actuator block in the piston rod slide to make the fork and output shaft in the actuator housing rotate forward and reverse, the valve opens or closes accordingly. At present, the existing pneumatic actuators mostly use rubber O-rings for dynamic sealing, which are more worn after long-term operation, resulting in failure of sealing performance and troublesome maintenance operations. Summary of the invention

[0003] In view of the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a double-acting pneumatic actuator to solve the problem that the existing pneumatic actuators mostly use rubber O-rings for dynamic sealing, which are greatly worn after long-term operation, resulting in failure of sealing performance and troublesome maintenance operations.

[0004] To achieve the above objectives and other related objectives, the present invention provides a double-acting pneumatic actuator, comprising:

[0005] The cylinder module comprises a cylinder assembly and a piston assembly, wherein the piston assembly is slidably connected to the cylinder assembly, and the piston assembly is provided with a sealing component and a wear-resistant belt in sequence along the radial direction of the cylinder assembly, wherein the sealing component contacts and seals with the wear-resistant belt, and the wear-resistant belt contacts and seals with the cylinder assembly;

[0006] A box module, wherein the box module has a first end and a second end along the length direction, the first end and the second end are both provided with a cylinder module, a guide assembly and a fork assembly are provided inside the box module, the guide assembly is used to guide the axial movement of the piston assembly along the cylinder assembly, the fork assembly is connected to the guide assembly, and the fork assembly is used to connect the valve rotating shaft and convert the linear motion of the piston assembly into the rotational motion of the valve rotating shaft.

[0007] Optionally, the cylinder assembly includes a cylinder body, a front cover and a rear cover, the front cover and the rear cover are respectively connected to two ends of the cylinder body along the axial direction, and the front cover and the rear cover are connected by a single-head screw.

[0008] Optionally, the rear cover has a plurality of through holes distributed along the circumferential direction, the through holes are opened along the thickness direction of the rear cover, and threaded holes are opened on the front cover corresponding to the through holes, the through holes are used to penetrate a single-head screw, the single-head screw is threadedly connected to the threaded hole, the single-head screw abuts against the rear cover, and the front cover and the rear cover are fixed to the cylinder body through the single-head screw.

[0009] Optionally, a sealing plate is provided on the rear cover, and the sealing plate is connected to the rear cover via a locking member. A limiting stud is provided on the sealing plate located at the first end of the box module, and the limiting stud is threadedly connected to the sealing plate. The limiting stud is used to limit the axial position of the piston assembly along the cylinder body.

[0010] Optionally, a locking nut is threadedly connected to the limiting stud, and the locking nut is used to abut against the sealing plate.

[0011] Optionally, a manual hydraulic device is provided on the sealing plate located at the second end of the box module, and the manual hydraulic device is used to drive the piston assembly to move axially along the cylinder body.

[0012] Optionally, the front cover and the rear cover are both provided with air source interfaces, and the air source interfaces are connected to the front cover and the rear cover by bolts.

[0013] Optionally, the guide assembly includes a guide rod and a guide block, two guide rods are provided in the box module, the guide rods extend along the axial direction of the cylinder body, the guide blocks are slidably arranged on the guide rods, and the piston assembly is connected to the guide blocks.

[0014] Optionally, the fork assembly includes a fork and a slider, the slider is connected to the guide block via a pin, the fork is connected to the valve rotating shaft, and a strip groove is provided on the fork, and the slider is slidably connected to the strip groove.

[0015] Optionally, a limiting sleeve is further provided on the sealing plate, the locking nut is arranged on the limiting sleeve, a sealing groove is provided on the locking nut, the sealing groove is used to install a sealing ring, and the limiting stud is located in the limiting sleeve.

[0016] As described above, the present invention has the following beneficial effects: the present application provides a cylinder module at both the first and second ends of the box module, thereby making the box module have a greater output torque; by sequentially providing a sealing method of a sealing component and a wear-resistant belt on the piston assembly along the radial direction of the cylinder assembly, the sealing component is in direct contact with the wear-resistant belt for sealing, and the wear-resistant belt is in frictional contact with the inner wall of the cylinder for sealing, effectively avoiding direct wear of the sealing component, ensuring the sealing performance of the cylinder assembly, and effectively extending the service life of the sealing component. The box module guides the axial movement of the piston assembly along the cylinder assembly by providing a guide assembly, so that the operation of the piston assembly is smoother, and by connecting a fork assembly to the guide assembly, and the fork assembly is connected to the valve rotating shaft, the linear motion of the piston assembly is converted into the rotational motion of the valve rotating shaft through the fork assembly, thereby realizing the opening and closing control of the valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Shown is a schematic structural diagram of a double-acting pneumatic actuator shown in an embodiment of the present application;

[0018] Figure 2 Shown is a schematic cross-sectional structure diagram of a double-acting pneumatic actuator shown in an embodiment of the present application;

[0019] Figure 3 Display as Figure 2 A magnified schematic diagram of the structure of the middle A section;

[0020] Figure 4 Display as Figure 1 Schematic diagram of the structure of the middle front cover;

[0021] Figure 5 Display as Figure 1 Schematic diagram of the structure of the middle and rear cover;

[0022] Figure 6 Shown is a schematic diagram of the structure of a limiting sleeve and a locking nut in an embodiment of the present application;

[0023] Figure 7 Shown as an exploded view of the enclosure module.

[0024] Description of Reference Numerals

[0025] Cylinder body 1011, front cover 1012, threaded hole 1012a, rear cover 1013, through hole 1013a, single-head screw 1014, sealing plate 1015, limiting sleeve 1015a, limiting stud 1016, locking nut 1017, sealing groove 1017a, piston assembly 102, piston head 1021, piston connecting rod 1022, sealing component 2, wear-resistant belt 3, box module 4, guide assembly 401, guide rod 4011, guide block 4012, fork assembly 402, fork 4021, strip groove 4021a, lower bushing 4021b, upper bushing 4021c, slider 4022, pin 4023, bottom shell 4024, box cover 4025, manual hydraulic device 5, air source interface 6, positioning step 7. DETAILED DESCRIPTION

[0026] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0027] See also Figures 1 to 7 It should be noted that the diagrams provided in the present embodiment only illustrate the basic concept of the present invention in a schematic manner, so the diagrams only show the components related to the present invention rather than drawing according to the number, shape and size of the components in actual implementation. The type, quantity and proportion of each component in actual implementation can be changed at will, and the component layout type may also be more complicated. The structure, proportion, size, etc. shown in the drawings attached to this specification are only used to match the content disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions that the present invention can be implemented, so they have no technical substantive significance. Any modification of the structure, change of the proportional relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effect and purpose that the present invention can produce. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. The change or adjustment of the relative relationship should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0028] Before describing the embodiments of the present invention in detail, the application environment of the present invention is described first. The technology of the present invention is mainly applied to the field of pneumatic actuator technology. The present invention is used to solve the problem that the existing pneumatic actuator dynamic sealing method mostly uses rubber O-rings, which wears out after long-term operation, resulting in failure of sealing performance and troublesome maintenance operations.

[0029] Please combine Figures 1 to 7 As shown, the present invention provides a double-acting pneumatic actuator.

[0030] In an exemplary embodiment of the present application, a double-acting pneumatic actuator includes: a cylinder module, including a cylinder assembly and a piston assembly 102, the piston assembly 102 is slidably connected to the cylinder assembly, the piston assembly 102 is sequentially provided with a sealing component 2 and a wear-resistant belt 3 along the radial direction of the cylinder assembly, the sealing component 2 is in contact and sealed with the wear-resistant belt 3, and the wear-resistant belt 3 is in contact and sealed with the cylinder assembly; a box module 4, the box module 4 has a first end and a second end along the length direction, the first end and the second end are both provided with a cylinder module, a guide assembly 401 and a fork assembly 402 are provided in the box module 4, the guide assembly 401 is used to guide the axial movement of the piston assembly 102 along the cylinder assembly, the fork assembly 402 is connected to the guide assembly 401, and the fork assembly 402 is used to connect the valve rotating shaft and convert the linear motion of the piston assembly 102 into the rotational motion of the valve rotating shaft.

[0031] In this embodiment, the present application provides a cylinder module at both the first and second ends of the box module, so that the box module 4 has a greater output torque; by sequentially providing a sealing method of a sealing component 2 plus a wear-resistant belt 3 on the piston assembly 102 along the radial direction of the cylinder assembly, the sealing component 2 is in direct contact with the wear-resistant belt 3 for sealing, and the wear-resistant belt 3 is in friction contact with the inner wall of the cylinder for sealing, which effectively avoids direct wear of the sealing component 2, ensures the sealing performance of the cylinder assembly, and can effectively extend the service life of the sealing component 2. The box module 4 guides the axial movement of the piston assembly 102 along the cylinder assembly by providing a guide assembly 401, so that the operation of the piston assembly 102 is smoother, and the fork assembly 402 is connected to the guide assembly 401, and the fork assembly 402 is connected to the valve rotating shaft, and the linear motion of the piston assembly 102 is converted into the rotational motion of the valve rotating shaft by the fork assembly 402, thereby realizing the opening and closing control of the valve.

[0032] It is worth noting that the piston assembly 102 includes a piston head 1021 and a piston connecting rod 1022. The sealing component 2 and the wear-resistant belt 3 are both arranged on the piston head 1021. The sealing component 2 is in direct contact with the wear-resistant belt 3 for sealing. The wear-resistant belt 3 is in friction contact with the inner wall of the cylinder assembly for sealing to avoid direct wear of the sealing component 2. The sealing component 2 is an O-ring.

[0033] In an exemplary embodiment of the present application, the cylinder assembly includes a cylinder body 1011, a front cover 1012 and a rear cover 1013, the front cover 1012 and the rear cover 1013 are respectively connected to the two ends of the cylinder body 1011 along the axial direction, and the front cover 1012 and the rear cover 1013 are connected by a single-head screw 1014.

[0034] In this embodiment, the front cover 1012 and the rear cover 1013 are used to seal the cylinder body 1011. Both the front cover 1012 and the rear cover 1013 are provided with positioning steps 7. The positioning steps 7 are used for quick positioning and assembly with the cylinder body 1011. After the positioning and assembly are completed, the front cover 1012, the rear cover 1013 and the cylinder body 1011 are fixedly connected by the single-head screw 1014, which effectively improves the assembly efficiency of the front cover 1012, the rear cover 1013 and the cylinder body 1011.

[0035] It is worth noting that the single-head screw 1014 has a hexagonal bolt head at one end along the length direction, and a thread is processed at the other end.

[0036] In an exemplary embodiment of the present application, the rear cover 1013 has a plurality of through holes 1013a distributed along the circumferential direction, the through holes 1013a are opened along the thickness direction of the rear cover 1013, and the front cover 1012 is provided with threaded holes 1012a corresponding to the through holes 1013a, the through holes 1013a are used to penetrate a single-head screw 1014, the single-head screw 1014 is threadedly connected to the threaded hole 1012a, the single-head screw 1014 is abutted against the rear cover 1013, and the front cover 1012 and the rear cover 1013 are fixed to the cylinder body 1011 through the single-head screw 1014.

[0037] In this embodiment, the diameters of the front cover 1012 and the rear cover 1013 are both larger than the diameter of the cylinder body 1011, the positioning step 7 is matched with the inner wall clearance of the cylinder body 1011, and the single-head screw 1014 passes through the through hole 1013a of the rear cover 1013 and is threadedly connected with the bolt hole of the front cover 1012, thereby fixing the front cover 1012 and the rear cover 1013 to the cylinder body 1011; the front cover 1012 and the rear cover 1013 are both provided with sealing rings around the positioning step 7, and the single-head screw 1014 can apply a pre-tightening force to the sealing ring during the process of fastening the front cover 1012, the rear cover 1013 and the cylinder body 1011, thereby achieving sealing at the connection position between the front cover 1012, the rear cover 1013 and the cylinder body 1011.

[0038] In an exemplary embodiment of the present application, a sealing plate 1015 is provided on the rear cover 1013, and the sealing plate 1015 is connected to the rear cover 1013 through a locking member. A limiting stud 1016 is provided on the sealing plate 1015 located at the first end of the box module 4, and the limiting stud 1016 is threadedly connected to the sealing plate 1015. The limiting stud 1016 is used to limit the axial position of the piston assembly 102 along the cylinder body 1011.

[0039] In this embodiment, the limiting stud 1016 is used to limit the axial movement of the piston assembly 102 along the cylinder body 1011, thereby controlling the opening and closing size of the valve.

[0040] In an exemplary embodiment of the present application, a locking nut 1017 is threadedly connected to the limiting stud 1016 , and the locking nut 1017 is used to abut against the sealing plate 1015 .

[0041] In this embodiment, the locking nut threadedly connected on the limit stud 1016 abuts against the sealing plate 1015, so that the limit stud 1016 can be fixed at the current position. The position of the limit stud 1016 can be adjusted by loosening the locking nut, thereby adjusting the movement stroke of the piston assembly 102 and further adjusting the opening and closing degree of the valve.

[0042] In an exemplary embodiment of the present application, a manual hydraulic device 5 is provided on the sealing plate 1015 located at the second end of the box module 4 , and the manual hydraulic device 5 is used to drive the piston assembly 102 to move axially along the cylinder body 1011 .

[0043] In this embodiment, the manual hydraulic device 5 is a hydraulic oil cylinder, and the oil cylinder shaft is connected to the piston head 1021 located in the cylinder body 1011 at the second end of the box module 4. The oil pump is manually operated to make the oil cylinder shaft extend and retract, and the piston assembly 102 is pushed to move along the axial direction of the cylinder body 1011, thereby driving the fork assembly 402 to rotate, and then driving the valve rotating shaft to rotate, so as to realize the opening and closing of the valve. By setting up the manual hydraulic device 5, the operator can realize the opening and closing of the valve through the manual hydraulic device 5 when there is no gas source or the production is stopped.

[0044] In an exemplary embodiment of the present application, both the front cover 1012 and the rear cover 1013 are provided with an air source interface 6 , and the air source interface 6 is connected to the front cover 1012 and the rear cover 1013 by bolts.

[0045] In this embodiment, the air source interface 6 is connected to the cylinder assembly by bolts, so that the air source interface 6 can be easily replaced according to different connection specification requirements.

[0046] In an exemplary embodiment of the present application, the guide assembly 401 includes a guide rod 4011 and a guide block 4012. Two guide rods 4011 are provided in the box module 4. The guide rods 4011 extend axially along the cylinder body 1011. The guide block 4012 is slidably set on the guide rod 4011, and the piston assembly 102 is connected to the guide block 4012.

[0047] In this embodiment, two guide rods 4011 are arranged in the box module 4, so that the axial movement of the guide block 4012 along the cylinder body 1011 is smoother. Since the piston assembly 102 is connected to the guide block 4012, the axial movement of the piston assembly 102 along the cylinder body 1011 is smoother.

[0048] In an exemplary embodiment of the present application, the fork assembly 402 includes a fork 4021 and a slider 4022, the slider 4022 is connected to the guide block 4012 through a pin 4023, the fork 4021 is connected to the valve rotating shaft, and a strip groove 4021a is provided on the fork 4021, and the slider 4022 is slidably connected to the strip groove 4021a.

[0049] In this embodiment, the slider 4022 is a square slider 4022, which is rotatably connected to the guide block 4012 through a pin shaft 4023. The fork 4021 is provided with a rectangular strip groove 4021a for cooperating with the slider 4022. The box module 4 also includes a bottom shell 4024 and a box cover 4025. The fork 4021 is connected to the bottom shell 4024 through a lower bushing 4021b, and the fork 4021 is connected to the box cover 4025 through an upper bushing 4021c. The fork 4021 is rotatably set on the box module 4 through the lower bushing 4021b and the upper bushing 4021c. The upper bushing 4021c and the lower bushing 4021b are both made of wear-resistant materials, including but not limited to metal materials such as copper, aluminum, and steel, or plastic materials with good self-lubrication and wear resistance. Air is introduced into the cylinder body 1011 through the air source connector, and the piston assembly 102 is pushed to move axially along the cylinder body 1011, and the guide block 4012 is driven to move axially along the guide rod 4011 through the piston assembly 102. Since the slider 4022 is rotatably set on the guide block 4012, the slider 4022 is slidably connected to the strip groove 4021a of the fork 4021, and the fork 4021 is rotatably connected to the box module 4, so that the fork assembly 402 can convert the linear movement of the guide block 4012 into the rotational movement of the fork 4021, thereby driving the valve rotation axis to rotate, and then realizing the opening and closing of the valve.

[0050] In an exemplary embodiment of the present application, a limiting sleeve 1015a is further provided on the sealing plate 1015, a locking nut 1017 is arranged on the limiting sleeve 1015a, a sealing groove 1017a is provided on the locking nut 1017, the sealing groove 1017a is used to install a sealing ring, and the limiting stud 1016 is located in the limiting sleeve 1015a.

[0051] In this embodiment, the limit stud 1016 is located in the limit sleeve 1015a, so as to prevent the limit stud 1016 from being directly exposed to the external environment, reduce the risk of rust on the limit stud 1016, and thus avoid the failure of the limit stud 1016 to limit the stroke of the piston assembly 102; by setting a sealing ring in the sealing groove 1017a of the locking nut 1017, the cylinder body 1011 is sealed at the connection position between the limit stud 1016 and the sealing plate 1015.

[0052] Working principle: the present application provides a cylinder module at both the first and second ends of the box module, so that the box module 4 has a greater output torque; the sealing method of the sealing component 2 plus the wear-resistant belt 3 is sequentially provided on the piston assembly 102 along the radial direction of the cylinder assembly, so that the sealing component 2 is in direct contact with the wear-resistant belt 3 for sealing, and the wear-resistant belt 3 is in friction contact with the inner wall of the cylinder for sealing, which effectively avoids direct wear of the sealing component 2, ensures the sealing performance of the cylinder assembly, and can effectively extend the service life of the sealing component 2. The box module 4 guides the axial movement of the piston assembly 102 along the cylinder assembly by providing a guide assembly 401, so that the operation of the piston assembly 102 is smoother, and the fork assembly 402 is connected to the guide assembly 401, and the fork assembly 402 is connected to the valve rotating shaft, and the linear motion of the piston assembly 102 is converted into the rotational motion of the valve rotating shaft by the fork assembly 402, thereby realizing the opening and closing control of the valve.

[0053] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A double-acting pneumatic actuator, characterized in that: include: The cylinder module comprises a cylinder assembly and a piston assembly, wherein the piston assembly is slidably connected to the cylinder assembly, and the piston assembly is provided with a sealing component and a wear-resistant belt in sequence along the radial direction of the cylinder assembly, wherein the sealing component contacts and seals with the wear-resistant belt, and the wear-resistant belt contacts and seals with the cylinder assembly; A box module, wherein the box module has a first end and a second end along the length direction, the first end and the second end are both provided with a cylinder module, a guide assembly and a fork assembly are provided inside the box module, the guide assembly is used to guide the axial movement of the piston assembly along the cylinder assembly, the fork assembly is connected to the guide assembly, and the fork assembly is used to connect the valve rotating shaft and convert the linear motion of the piston assembly into the rotational motion of the valve rotating shaft.

2. The double-acting pneumatic actuator according to claim 1, characterized in that: The cylinder assembly comprises a cylinder body, a front cover and a rear cover. The front cover and the rear cover are respectively connected to two ends of the cylinder body along the axial direction. The front cover and the rear cover are connected by a single-head screw.

3. The double-acting pneumatic actuator according to claim 2, characterized in that: The rear cover has a plurality of through holes distributed along the circumferential direction, and the through holes are opened along the thickness direction of the rear cover. The front cover has threaded holes corresponding to the through holes, and the through holes are used to pass a single-head screw, which is threadedly connected to the threaded holes, and the single-head screw abuts against the rear cover, and the front cover and the rear cover are fixed to the cylinder body through the single-head screw.

4. The double-acting pneumatic actuator according to claim 3, characterized in that: A sealing plate is provided on the rear cover, and the sealing plate is connected to the rear cover via a locking piece. A limiting stud is provided on the sealing plate at the first end of the box module, and the limiting stud is threadedly connected to the sealing plate. The limiting stud is used to limit the axial position of the piston assembly along the cylinder body.

5. The double-acting pneumatic actuator according to claim 4, characterized in that: A locking nut is threadedly connected to the limiting stud, and the locking nut is used to abut against the sealing plate.

6. The double-acting pneumatic actuator according to claim 5, characterized in that: A manual hydraulic device is provided on the sealing plate at the second end of the box module, and the manual hydraulic device is used to drive the piston assembly to move along the axial direction of the cylinder body.

7. The double-acting pneumatic actuator according to claim 2, characterized in that: The front cover and the rear cover are both provided with air source interfaces, and the air source interfaces are connected to the front cover and the rear cover by bolts.

8. The double-acting pneumatic actuator according to claim 7, characterized in that: The guide assembly includes a guide rod and a guide block. Two guide rods are arranged in the box module. The guide rods extend along the axial direction of the cylinder body. The guide blocks are slidably arranged on the guide rods. The piston assembly is connected to the guide blocks.

9. The double-acting pneumatic actuator according to claim 8, characterized in that: The shift fork assembly comprises a shift fork and a slider, the slider is connected to the guide block via a pin, the shift fork is connected to the valve rotating shaft, and a strip groove is provided on the shift fork, and the slider is slidably connected to the strip groove.

10. The double-acting pneumatic actuator according to claim 5, characterized in that: The sealing plate is also provided with a limiting sleeve, the locking nut is arranged on the limiting sleeve, the locking nut is provided with a sealing groove, the sealing groove is used to install a sealing ring, and the limiting stud is located in the limiting sleeve.

Images