Pneumatic actuating mechanism

Abstract

The utility model relates to the technical field of valves, in particular to a pneumatic executing mechanism. The pneumatic executing mechanism comprises an air cylinder assembly, a rotation assembly and a connecting base, the air cylinder assembly comprises an air cylinder piston and a connecting shaft, and the air cylinder piston is connected with the connecting shaft and drives the connecting shaft to do linear motion; the rotation assembly comprises a transmission shaft and a conversion shaft, the transmission shaft is connected with the connecting shaft, the connecting shaft drives the transmission shaft to do linear motion, the transmission shaft comprises a sliding part, the sliding part is arranged at the end, away from the connecting shaft, of the transmission shaft, a spiral sliding way is arranged on the conversion shaft, and the sliding part of the transmission shaft can move in the sliding way to enable the conversion shaft to rotate around the axis of the conversion shaft. The conversion shaft is connected with the valve; and one end of the connecting seat is connected with the air cylinder assembly, and the other end of the connecting seat is connected with the valve. According to the pneumatic actuating mechanism, the axial movement of the air cylinder piston is converted into the rotary movement of the conversion shaft, and the pneumatic actuating mechanism has the rapid reaction capacity and also has the large-torque output characteristic.

Description

Technical Field

[0001] This application relates to the technical field of valves, and particularly to a pneumatic actuator. Background Art

[0002] In recent years, with the continuous development of the modernization process, valve technology also needs to adapt to the development of new products. Especially for the valve control actuators applicable to pipeline transportation stations for special items such as natural gas and petroleum, they need to have the performance of withstanding harsh working conditions.

[0003] In the existing pneumatic actuator, the impact force of the actuator on the valve is relatively large during the process of opening and closing the valve, and a high-power power supply configuration is required to output a large amount of power. There is a lack of a valve actuator that has both the fast response ability of a pneumatic actuator and the output characteristic of a large torque. Therefore, there is an urgent need for a new type of power actuator in the industry. Summary of the Utility Model

[0004] In order to solve the above technical problems or at least partially solve the above technical problems, this application provides a pneumatic actuator.

[0005] This application provides a pneumatic actuator, including:

[0006] A cylinder assembly, the cylinder assembly includes a cylinder piston and a connecting shaft, the cylinder piston is connected to the connecting shaft and drives the connecting shaft to perform a linear motion;

[0007] A rotary assembly, the rotary assembly includes a transmission shaft and a conversion shaft, the transmission shaft is connected to the connecting shaft, the connecting shaft drives the transmission shaft to perform a linear motion, the transmission shaft includes a sliding portion, the sliding portion is arranged at one end of the transmission shaft far from the connecting shaft, a spiral-shaped slideway is arranged on the conversion shaft, and the sliding portion of the transmission shaft can move in the slideway to make the conversion shaft rotate around its axis, and the conversion shaft is connected to the valve;

[0008] A connecting seat, the connecting seat is arranged outside the rotary assembly, one end of the connecting seat is connected to the cylinder assembly, and the other end is connected to the valve.

[0009] Optionally, each sliding portion includes a pin shaft and a rolling sleeve, the pin shaft is arranged in the rolling sleeve, one end of the pin shaft is fixed to the shaft body of the transmission shaft, the other end is matched with the rolling sleeve, and the rolling sleeve can roll in the slideway.

[0010] Optionally, the spiral track of the slideway is an unequal pitch spiral curve.

[0011] Optionally, multiple slideways are arranged, the number of sliding portions is the same as the number of slideways, and each sliding portion moves in one of the slideways respectively.

[0012] Optionally, the plurality of the slideways are equally circumferentially arranged around the conversion shaft.

[0013] Optionally, the connecting shaft of the cylinder assembly, the transmission shaft of the rotary assembly and the conversion shaft are coaxially arranged.

[0014] Optionally, the cylinder assembly includes an upper end cover, a cylinder barrel and a lower end cover. The upper end cover, the cylinder barrel and the lower end cover enclose a housing structure for accommodating the cylinder piston and the connecting shaft. The lower end cover is provided with a perforation, and the transmission shaft passes through the perforation and is connected to the connecting shaft.

[0015] Optionally, the connecting shaft is in threaded connection with the transmission shaft.

[0016] Optionally, the cylinder assembly includes a shaft stop turntable, and the shaft stop turntable is installed between the lower end cover and the transmission shaft. The shaft stop turntable is used to limit the rotation of the transmission shaft.

[0017] Optionally, the rotary assembly includes a plurality of thrust bearings, and the plurality of thrust bearings are respectively arranged at the upper and lower end shoulders of the conversion shaft.

[0018] In the pneumatic actuator provided in this application, the cylinder piston is connected to the connecting shaft. When the cylinder piston moves linearly along its axis, it will drive the connecting shaft to move linearly synchronously. Also, because the transmission shaft is connected to the connecting shaft, the connecting shaft drives the transmission shaft to also move linearly. The sliding part of the transmission shaft can move in the slideway of the conversion shaft, and the slideway is spiral. Therefore, when the sliding part moves in the slideway, it will cause the conversion shaft to rotate, thereby realizing the conversion of the axial movement of the cylinder piston into the rotary movement of the conversion shaft. The conversion shaft is connected to the valve and can open and close the valve. In addition, one end of the connecting seat is connected to the cylinder assembly, and the other end is connected to the valve. While playing a connecting role, the connecting seat can also support the cylinder assembly. The pneumatic actuator in this embodiment has a fast response ability and also has the output characteristic of large torque. Description of the Drawings

[0019] The drawings here are incorporated into the specification and form a part of this specification, showing the embodiments consistent with this application and used together with the specification to explain the principles of this application.

[0020] In order to more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the following will briefly introduce the drawings required to be used in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0021] Figure 1Schematic diagram of the pneumatic actuator according to an embodiment of the present application;

[0022] Figure 2 Schematic structural diagram of the conversion shaft according to an embodiment of the present application.

[0023] The reference signs in the detailed implementation manners are as follows:

[0024] 10. Cylinder assembly; 11. Cylinder piston; 12. Connecting shaft; 13. Upper end cover; 14. Cylinder barrel; 15. Lower end cover; 16. Shaft stop turntable; 20. Rotary assembly; 21. Transmission shaft; 211. Sliding part; 211a. Pin shaft; 211b. Sleeve; 22. Conversion shaft; 221. Slideway; 23. Thrust bearing; 30. Connecting seat. Detailed implementation manners

[0025] In order to be able to more clearly understand the above-mentioned objects, features and advantages of the present application, the solution of the present application will be further described below. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0026] Many specific details are set forth in the following description in order to fully understand the present application, but the present application can also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only a part of the embodiments of the present application, rather than all the embodiments.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusion.

[0028] In the description of the embodiments of the present application, the meanings of "a plurality" and "several" are two or more (including two), unless otherwise specifically defined.

[0029] Referring to "embodiment" herein means that a specific feature, structure or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0030] According to some embodiments of the present application, referring to Figure 1 as shown, wherein, Figure 1Schematic diagram of the pneumatic actuator according to the embodiment of the present application. The pneumatic actuator according to the embodiment of the present application includes a cylinder assembly 10, a rotary assembly 20, and a connecting seat 30. The cylinder assembly 10 includes a cylinder piston 11 and a connecting shaft 12. The cylinder piston 11 is connected to the connecting shaft 12 and drives the connecting shaft 12 to perform a linear motion. The rotary assembly 20 includes a transmission shaft 21 and a conversion shaft 22. The transmission shaft 21 is connected to the connecting shaft 12. The connecting shaft 12 drives the transmission shaft 21 to perform a linear motion. The transmission shaft 21 includes a sliding portion 211. The sliding portion 211 is provided at one end of the transmission shaft 21 away from the connecting shaft 12. A spiral chute 221 is provided on the conversion shaft 22. The sliding portion 211 of the transmission shaft 21 can move within the chute 221, causing the conversion shaft 22 to rotate about its axis. The conversion shaft 22 is connected to the valve. The connecting seat 30 is provided outside the rotary assembly 20. One end of the connecting seat 30 is connected to the cylinder assembly 10, and the other end is connected to the valve. The connecting shaft 12 of the cylinder assembly 10, the transmission shaft 21 of the rotary assembly 20, and the conversion shaft 22 are coaxially arranged.

[0031] The cylinder piston 11 is connected to the connecting shaft 12. When the cylinder piston 11 performs a linear motion on its axis, it will drive the connecting shaft 12 to perform a synchronous linear motion. Also, because the transmission shaft 21 is connected to the connecting shaft 12, the connecting shaft 12 drives the transmission shaft 21 to perform a linear motion as well. The sliding portion 211 of the transmission shaft 21 can move within the chute 221 of the conversion shaft 22. The chute 221 is spiral. Therefore, when the sliding portion 211 moves within the chute 221, it will cause the conversion shaft 22 to rotate, thereby realizing the conversion of the axial motion of the cylinder piston 11 into the rotary motion of the conversion shaft 22. The conversion shaft 22 is connected to the valve, enabling the valve to be opened and closed. In addition, one end of the connecting seat 30 is connected to the cylinder assembly 10, and the other end is connected to the valve. The connecting seat 30 not only plays a connecting role but also can support the cylinder assembly 10. The pneumatic actuator in this embodiment has a fast response ability and also has the output characteristic of large torque. The connecting shaft 12, the transmission shaft 21, and the conversion shaft 22 are coaxially arranged, effectively utilizing the upper space of the valve, improving the overall compactness of the valve, and being able to improve the force conversion efficiency.

[0032] Reference Figure 1, in other embodiments, the cylinder assembly 10 includes an upper end cover 13, a cylinder barrel 14, and a lower end cover 15. The upper end cover 13, the cylinder barrel 14, and the lower end cover 15 enclose a housing structure for accommodating the cylinder piston 11 and the connecting shaft 12. The lower end cover 15 is provided with a perforation, and the transmission shaft 21 passes through the perforation and is connected to the connecting shaft 12. The housing structure enclosed by the upper end cover 13, the cylinder barrel 14, and the lower end cover 15 can protect the core components such as the cylinder piston 11 and the connecting shaft 12 inside it, preventing the cylinder piston 11 and the connecting shaft 12 from being damaged by external impacts, and at the same time can also play a role in dust and water protection. The connecting shaft 12 is threadedly connected to the transmission shaft 21. Specifically, a connecting groove is provided on the transmission shaft 21, a first connecting thread is provided in the connecting groove, a second connecting thread is provided on the connecting shaft 12, and the connecting shaft 12 is threadedly connected to the connecting groove of the transmission shaft 21. Refer to Figure 1 , each sliding part 211 includes a pin shaft 211a and a rolling sleeve 211b. The pin shaft 211a is arranged inside the rolling sleeve 211b. One end of the pin shaft 211a is fixed to the shaft body of the transmission shaft 21, and the other end is rotatably connected to the rolling sleeve 211b, and the rolling sleeve 211b can roll in the slideway 221.

[0033] Since the pin shaft 211a and the rolling sleeve 211b can rotate relative to each other, and the rolling sleeve 211b can roll in the slideway 221, the sliding friction generated when the rolling sleeve 211b slides in the slideway 221 is thus converted into rolling friction, so as to reduce the friction coefficient and improve the mechanical efficiency.

[0034] As Figure 2 shown, Figure 2 is a schematic structural diagram of the conversion shaft according to an embodiment of the present application. The spiral trajectory of the slideway 221 is a non-uniform pitch spiral curve. A plurality of slideways 221 are provided, and the number of sliding parts 211 is the same as the number of slideways 221. Each sliding part 211 moves in one slideway 221 respectively. The plurality of slideways 221 are equally divided in the circumferential direction of the conversion shaft 22.

[0035] Specifically, "the spiral trajectory of the slideway 221 is a non-uniform pitch spiral curve" means that the pitch at both ends of each slideway 221 is greater than the pitch at the middle section. The slideways 221 are preferably equally divided in the circumferential direction by four.

[0036] A plurality of slideways 221 are provided, which can achieve a larger torque with a smaller force, so as to have the output characteristic of large torque. The pitch at both ends of each slideway 221 is greater than the pitch at the position of the middle section. Preferably, the pitch at both ends of each slideway 221 is more than twice the pitch at the position of the middle section, and the pitch sizes at both ends of each slideway 221 are the same. During the process of opening and closing the valve, the rotational speed of the conversion shaft 22 starts from zero and accelerates, reducing the impact on the valve stem when starting to open the valve; then it rotates at a constant speed to ensure the efficiency of opening the valve; finally, it decelerates to reduce the impact on the valve stem when closing the valve. Similarly, when closing the valve, since the pitch change on the slideway 221 is symmetric, the process of closing the valve is the same as the process of opening the valve, which will not be elaborated here. Therefore, this process can realize the three action processes of acceleration, constant speed, and deceleration during the valve opening and closing process, reducing the impact of the actuator on the valve, and at the same time ensuring the large torque opening or closing moment required when the valve is in the closed position.

[0037] In some embodiments, referring to Figures 1 to 2 , the cylinder assembly 10 includes an axial stop turntable 16, and the axial stop turntable 16 is installed between the lower end cover 15 and the transmission shaft 21. The axial stop turntable 16 is used to limit the rotation of the transmission shaft 21. The slewing assembly 20 includes a plurality of thrust bearings 23, and the plurality of thrust bearings 23 are respectively arranged at the upper and lower end shoulders of the conversion shaft 22.

[0038] Since the rolling sleeve 211b rolls in the slideway 221 and the conversion shaft 22 rotates, a force will inevitably act on the transmission shaft 21. The axial stop turntable 16 is installed between the lower end cover 15 and the transmission shaft 21. The axial stop turntable 16 serves as a guiding mechanism, which can prevent the transmission shaft 21 from rotating, and at the same time, it is also used to ensure the movement of the transmission shaft 21 in its axial direction. The number of thrust bearings 23 is preferably two, and the two thrust bearings 23 are respectively arranged at the upper and lower end shoulders of the conversion shaft 22. The thrust is used to bear the axial load. The up and down movement of the conversion shaft 22 is restricted so that it can only rotate. Specifically, when the cylinder piston 11 moves downward, the thrust bearing 23 at the lower end shoulder of the conversion shaft 22 is stressed to prevent it from continuing to move downward; when the cylinder piston 11 moves upward, the thrust bearing 23 at the upper end shoulder of the conversion shaft 22 is stressed to prevent it from continuing to move upward.

[0039] The working principle of the pneumatic actuator will be introduced in detail below.

[0040] The cylinder piston 11 is connected to the connecting shaft 12. When the cylinder piston 11 moves linearly along its axis, it will drive the connecting shaft 12 to move linearly synchronously. Also, since the transmission shaft 21 is connected to the connecting shaft 12, the connecting shaft 12 drives the transmission shaft 21 to move linearly as well. The sliding part 211 of the transmission shaft 21 can move within the slideway 221 of the conversion shaft 22, and the slideway 221 is spiral. Therefore, when the sliding part 211 moves in the slideway 221, it will cause the conversion shaft 22 to rotate, thereby realizing the conversion of the axial movement of the cylinder piston 11 into the rotary movement of the conversion shaft 22. The conversion shaft 22 is connected to the valve, and the opening and closing of the valve can be realized. On this basis, the sliding part 211 includes a pin shaft 211a and a rolling sleeve 211b. Since the pin shaft 211a and the rolling sleeve 211b can rotate relative to each other, the rolling sleeve 211b can roll within the slideway 221, thereby realizing the conversion of the sliding friction force generated when the rolling sleeve 211b moves in the slideway 221 into a rolling friction force, reducing the friction coefficient and improving the mechanical efficiency. At the same time, the spiral trajectory of the slideway 221 is a non-uniform pitch spiral curve, and the pitch at both ends of each slideway 221 is greater than the pitch at the middle section. During the process of opening and closing the valve, the rotational speed of the conversion shaft 22 starts from zero and accelerates, reducing the impact on the valve stem when starting to open the valve; then it rotates at a constant speed to ensure the efficiency of opening the valve; finally, it decelerates to reduce the impact on the valve stem when closing the valve. Similarly, when closing the valve, since the change in pitch on the slideway 221 is symmetric, the process of closing the valve is the same as the process of opening the valve, which will not be elaborated here. Therefore, this process can realize the three action processes of acceleration, constant speed, and deceleration during the process of opening and closing the valve, reducing the impact of the actuator on the valve, and at the same time ensuring the large torque opening or closing moment required for the valve in the closed position.

[0041] The content of this application is not limited to the examples listed. Any equivalent transformation of the technical solution of this application by those of ordinary skill in the art through reading the specification of this application is covered by the claims of this application.

[0042] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of this application, not to limit them; although this application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and the specification of this application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. This application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions falling within the scope of the claims.

Claims

1. A pneumatic actuator, characterized in that, Comprising: A cylinder assembly (10), the cylinder assembly (10) including a cylinder piston (11) and a connecting shaft (12), the cylinder piston (11) being connected to the connecting shaft (12) and driving the connecting shaft (12) to perform a linear motion; A rotary assembly (20), the rotary assembly (20) including a transmission shaft (21) and a conversion shaft (22), the transmission shaft (21) being connected to the connecting shaft (12), the connecting shaft (12) driving the transmission shaft (21) to perform a linear motion, the transmission shaft (21) including a sliding portion (211), the sliding portion (211) being provided at one end of the transmission shaft (21) far from the connecting shaft (12), a spiral-shaped slideway (221) being provided on the conversion shaft (22), the sliding portion (211) of the transmission shaft (21) being capable of moving within the slideway (221) to cause the conversion shaft (22) to rotate about its axis, the conversion shaft (22) being connected to a valve; A connecting seat (30), the connecting seat (30) being provided outside the rotary assembly (20), one end of the connecting seat (30) being connected to the cylinder assembly (10) and the other end being connected to the valve.

2. The pneumatic actuator according to claim 1, wherein, Each of the sliding portions (211) includes a pin shaft (211a) and a rolling sleeve (211b), the pin shaft (211a) being disposed within the rolling sleeve (211b), one end of the pin shaft (211a) being fixed to the shaft body of the transmission shaft (21) and the other end being in cooperation with the rolling sleeve (211b), and the rolling sleeve (211b) being capable of rolling within the slideway (221).

3. The pneumatic actuator according to claim 1, characterized in that, The spiral-shaped track of the slideway (221) is a non-uniform pitch spiral curve.

4. The pneumatic actuator according to any one of claims 1-3, characterized in that, A plurality of the slideways (221) are provided, the number of the sliding portions (211) being the same as the number of the slideways (221), and each of the sliding portions (211) moves within one of the slideways (221) respectively.

5. The pneumatic actuator according to claim 4, wherein The plurality of the slideways (221) are equally circumferentially arranged on the conversion shaft (22).

6. The pneumatic actuator according to claim 1, characterized in that, The connecting shaft (12) of the cylinder assembly (10), the transmission shaft (21) of the rotary assembly (20), and the conversion shaft (22) are coaxially arranged.

7. The pneumatic actuator according to claim 1, characterized in that, The cylinder assembly (10) includes an upper end cover (13), a cylinder barrel (14), and a lower end cover (15), the upper end cover (13), the cylinder barrel (14), and the lower end cover (15) enclosing a housing structure for accommodating the cylinder piston (11) and the connecting shaft (12), the lower end cover (15) being provided with a perforation, and the transmission shaft (21) passing through the perforation to be connected to the connecting shaft (12).

8. The pneumatic actuator according to claim 7, characterized in that, The connecting shaft (12) is threadedly connected to the transmission shaft (21).

9. The pneumatic actuator according to claim 7, characterized in that, The cylinder assembly (10) includes an axial stop turntable (16), the axial stop turntable (16) being installed between the lower end cover (15) and the transmission shaft (21), and the axial stop turntable (16) being used for restricting the rotation of the transmission shaft (21).

10. The pneumatic actuator according to claim 1, characterized in that, The rotary assembly (20) includes a plurality of thrust bearings (23), and the plurality of thrust bearings (23) are respectively provided at the upper and lower end shoulders of the conversion shaft (22).

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