CN212080302U

CN212080302U - Single-action shifting fork type pneumatic actuator

Info

Publication number: CN212080302U
Application number: CN202020498633.0U
Authority: CN
Inventors: 付斌斌
Original assignee: Shaanxi Improvement Fluid Control Equipment Manufacturing Co ltd
Current assignee: Shaanxi Improvement Fluid Control Equipment Manufacturing Co ltd
Priority date: 2020-04-08
Filing date: 2020-04-08
Publication date: 2020-12-04
Anticipated expiration: 2030-04-08

Abstract

The single-action shifting fork type pneumatic actuator comprises a cylinder, a box body, a spring cylinder, a piston rod and a spring seat; the left end of the piston rod is connected with the right end of the right spring seat of the spring cylinder in a pushing and coaxial manner; the left end of the compression spring is coaxially sleeved and connected with the right end of the left spring seat; an adjusting bolt is coaxially screwed in the axial center of the left spring seat to adjust the left limit; the middle part of the rod body of the piston rod pushes a shifting fork with an axisymmetric structure to rotate through a pin shaft; and the torque is output through a transmission shaft fixedly connected with the upper end of the shifting fork through a positioning pin; two ends of the transmission shaft are rotatably supported and installed in the box body through axisymmetric shaft sleeves; and the inner side wall of the cylinder body is provided with a PTFE coating. The utility model has simple structure, compact design and small volume; the assembly is modularized, the processing is simple and convenient, and the operation is convenient; the response is quick, and the transmission is stable, reliable and efficient; can realize large torque output and has the comprehensive advantages of economy, practicability and optimal cost performance.

Description

Single-action shifting fork type pneumatic actuator

Technical Field

The utility model belongs to the technical field of the valve, concretely relates to single-action shifting fork type pneumatic actuator.

Background

At present, a single-action shifting fork type pneumatic actuator is generally composed of a single-action cylinder, a shifting fork box body and a spring cylinder reset mechanism. Chinese patent No. CN206419533U discloses a novel single-acting pneumatic actuator. However, the actuator has the disadvantages that: firstly, a spring cylinder reset mechanism adopts an extension spring to realize reset; in the case of an extension spring, the extension spring is a coil spring subjected to an axial tensile force; are generally made of only cross-section round materials; the selection of the section form of the spring has certain limitation; limiting the possibilities of actuator modifications to the spring in special circumstances. Moreover, the two ends of the extension spring are reliably and fixedly connected with the force bearing part to realize the effective transmission of the extension torque, and the technical scheme adopts a bolt fastening mode to realize the fixed connection; the installation convenience and the anti-loosening durability of the fastener are improved; secondly, the actuator adopts a plunger cylinder and plunger design, the complexity of the structural design of the actuator is increased by plunger adjustment, the requirement on the manufacturing process is higher, and the cost of the actuator is increased; in addition, the complexity of the actuator structure is also a problem in the fork mechanism. The following improvement is proposed.

SUMMERY OF THE UTILITY MODEL

The utility model provides a technical problem: the single-action shifting fork type pneumatic actuator is provided, and the problem that the universality application field of the actuator is limited due to the limitation of the spring structure design in a spring cylinder reset mechanism in the prior art is solved; the technical problem that the cost of the actuator is too high due to the fact that the structural design of the limit position adjusting mechanism and the torque output mechanism of the actuator is too complex is solved.

The utility model adopts the technical proposal that: the single-action shifting fork type pneumatic actuator comprises a cylinder, a box body, a spring cylinder, a piston rod and a spring seat; the piston is arranged in the cylinder, and the right end of the piston rod extends into the cylinder body of the cylinder and is coaxially and fixedly connected with the piston; the method is characterized in that: the left end of the piston rod penetrates through the box body and then extends into the spring cylinder body to be connected with the right end of the right spring seat in a pushing and coaxial mode; the left end of the right spring seat is coaxially sleeved and fixedly connected with the right end of the compression spring; the left end of the compression spring is coaxially sleeved and connected with the right end of the left spring seat; the outer side of the left spring seat body is coaxially and fixedly connected with the left end of the spring cylinder body into a whole in a sealing manner; a horizontal axial threaded through hole is formed in the axial center of the left spring seat; the threaded through hole is coaxially screwed with an adaptive adjusting bolt; the adjusting bolt and the adjusting nut are arranged outside the cylinder body, and the screw rod extends into the cylinder body to axially adjust and limit the left limit of the piston rod and the right spring seat; the middle part of the piston rod body is hinged with the middle part of the pin shaft body; two ends of the pin shaft are hinged with the lower ends of the shifting forks of the axial symmetry structure; the upper end of the shifting fork is fixedly connected with the middle part of the shaft body of the transmission shaft through a positioning pin, and the torque is output through the transmission shaft; two ends of the transmission shaft are rotatably supported and mounted in the box body through shaft sleeves which are arranged in an axisymmetric manner; and the inner side wall of the cylinder body is provided with a PTFE coating.

Among the above-mentioned technical scheme, in order to realize the executor to the deformation user demand of compression spring shape under different environment, further: the compression spring comprises a cylindrical, conical compression spring; the section of the compression spring body is circular or rectangular.

In the technical scheme, the axial resetting elastic function of the compression spring is not influenced when the compression spring is installed in order to simplify the installation of the compression spring; further: the longitudinal sections of the left spring seat and the right spring seat are T-shaped; the left horizontal shaft and the right horizontal shaft of the left T-shaped horizontal bulge part and the right T-shaped horizontal bulge part of the left spring seat and the right spring seat are symmetrically and oppositely arranged; the left end and the right end of the ring of the compression spring are respectively sleeved and connected with the horizontal convex parts of the left spring seat and the right spring seat in a coaxial clearance fit manner.

Among the above-mentioned technical scheme, when adjusting bolt realized spacing regulation through the rotating, for guaranteeing that it has more reliable spacing stopping function, preferably: the thread through hole and the thread profile of the adjusting bolt are rectangular or trapezoidal.

Among the above-mentioned technical scheme, for adopting the self-lubricating function that comparatively simple structure realized the axle sleeve, preferably: the shaft sleeve is a copper shaft sleeve with a self-lubricating function; and the longitudinal section of the shaft sleeve is of a T-shaped structure.

Among the above-mentioned technical scheme, for realizing that shift fork lower extreme open end is connected with the simple reliable ground at round pin axle both ends, furtherly: the two ends of the pin shaft are blocked by axial limiting clamps of a shaft end clamp spring on the two ends of the pin shaft in a clearance fit and rotating manner, and the clamp sleeves are arranged in a circular ring structure; the upper end surface and the lower end surface of the outer cylindrical surface of the clamping sleeve body are respectively provided with an axisymmetric limiting clamping groove, and the section of the clamping sleeve after the limiting clamping groove is longitudinally cut is in an I-shaped structure; the upper limiting clamping groove and the lower limiting clamping groove are axially symmetrical and are arranged in parallel up and down; the limiting clamping groove of the clamping sleeve is in adaptive insertion with the gap of the lower end opening of the shifting fork body so as to pull the lower end opening of the shifting fork and the pin shaft to be hinged into a whole.

In the above-mentioned technical scheme, in order to improve the reliability of the big moment of torsion output of transmission shaft, further: an annular groove I is formed at the fixed matching position of the outer cylindrical surface of the shaft sleeve body and the box body, and a rectangular section sealing ring is arranged in the annular groove I; an annular groove II is formed at the rotating matching position of the outer cylindrical surface of the shaft end of the transmission shaft and the shaft sleeve; and a rectangular section sealing ring is arranged in the annular groove II.

Among the above-mentioned technical scheme, for adopting simple compact structure to realize the output of big moment of torsion, further: the shifting fork is of a U-shaped axisymmetric double-fork-head shifting fork structure, the U-shaped closed end of the shifting fork is of a solid block structure with a certain thickness, and the axisymmetric center of the solid block is provided with a jack; the jack is in adaptive insertion connection with one end of the positioning pin; the other end of the positioning pin is matched and inserted with a through hole formed in the middle of the shaft body of the transmission shaft; the shifting fork prizes the transmission shaft to rotate through the positioning pin so as to output torque; the depth of the positioning pin inserted into the insertion hole is larger than that of the positioning pin inserted into the transmission shaft, and the depth of the insertion hole is larger than one half of the axial length of the positioning pin.

Compared with the prior art, the utility model have following advantage:

1. the scheme adopts the reset elasticity of the compression spring to realize the reset of the piston rod of the pneumatic actuating mechanism; compared with an extension spring, the transmission structure is simpler, the assembly of the spring and the spring seat is more convenient, the spring and the spring seat are not required to be fastened and connected into a whole, and the efficient transmission and resetting of the axial torque can be realized only by adjacent contact; the difficulty of the processing and assembling process is greatly reduced; moreover, the structure of the compression spring is more varied, and proper modification design is more possible according to the change of the environment; the universality is more ideal;

2. according to the scheme, the spring seat is provided with the adjusting bolt after the hole is formed through the threads, so that the limit position of the piston rod can be adjusted; compared with a plunger type design, the structure is simpler, the process precision requirement is lower, the realization is easier, and the limit position adjusting operation is simple and convenient; therefore, the method is more economical and practical; the adjusting bolt adopts rectangular or trapezoidal teeth, so that the adjusting bolt has a more reliable limiting and retaining function;

3. the shifting fork actuating mechanism adopts an axisymmetric structure and combines a lever type prying principle to realize torque transmission; the structure is compact, and the volume is small; but also has the advantages of more labor-saving, reliable, rapid and efficient transmission;

4. the inner wall of the cylinder is designed by adopting a PTFE (polytetrafluoroethylene) coating; can be continuously used at 260 ℃, has the highest use temperature of 290 ℃ and 300 ℃, has extremely low friction coefficient, good wear resistance and excellent chemical stability; the surface smoothness of the movement of the cylinder piston is increased, the friction force is greatly reduced, and the corrosion resistance is realized; the transmission of the miniature shifting fork is cooperated; the torque of the actuator is increased, the reaction speed of the actuator is improved, and the 90-degree opening and closing are efficient, reliable and rapid;

5. according to the scheme, the shaft sleeve of the copper T-shaped structure cooperates with the sealing ring to realize the self-lubricating function of the transmission shaft; meanwhile, the more reliable and stable output of the torque at the shaft end of the transmission shaft is realized; a U-shaped axisymmetric double-fork-head shifting fork structure; the structure is compact, and the volume is small; the transmission is efficient and stable, and the response is rapid; the torque output of the transmission shaft is realized by adopting a prying mode; the matched connection between the positioning pin and the transmission shaft and between the positioning pin and the shifting fork is realized by adopting a plug-in mounting mode; the requirement on the dimensional matching precision is low; the structure is simple, the processing is easy, the assembly is convenient, and the device is economical and practical;

6. the scheme has the advantages of simple structure, compact design, small volume, modular assembly, convenient assembly and convenient operation; the response is quick, the transmission is stable, reliable and efficient, the large torque output can be realized, and the device is economical and practical.

Drawings

FIG. 1 is a schematic view of the external three-dimensional structure of the present invention;

FIG. 2 is an exploded view of the transmission principle of the present invention;

FIG. 3 is a perspective view of the transmission principle of the torque output of the shifting fork in the box body of the present invention;

FIG. 4 is a cross-sectional view of the transmission principle of the torque output of the shifting fork in the box body of the utility model;

FIG. 5 is a cross-sectional view of the clamping sleeve for tightly fitting the pin shaft end of the present invention;

fig. 6 is a perspective view of the ferrule of fig. 5;

fig. 7 is a front view of the pin.

Detailed Description

Specific embodiments of the present invention will be described below with reference to fig. 1 to 6. It is to be understood that the following description of the embodiments is merely exemplary and not intended to limit the invention in any way.

The following examples are provided to facilitate a better understanding of the present invention, but are not intended to limit the present invention. The pneumatic execution methods of the cylinder, the piston and the piston rod in the following embodiments are all conventional methods. The materials for the members used in the following examples are commercially available unless otherwise specified.

In the present invention, without the contrary explanation, it is understood that: the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are merely for convenience of description of the present invention, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that unless otherwise explicitly stated or limited, the terms "mounted," "connected," "disposed," and "provided" are to be construed broadly and may, for example, be fixedly connected, disposed, detachably connected, disposed, or integrally connected and disposed. For example, they may be directly connected to each other or indirectly connected to each other through other intermediate members. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The single-acting shifting fork type pneumatic actuator (shown in figures 1 and 2) comprises a cylinder 1, a box body 2, a spring cylinder 3, a piston 4, a piston rod 5 and a spring seat; the piston 4 is installed in the cylinder 1, and the matching mode of the piston and the cylinder 1 belongs to the prior art and is not described in detail. The cylinder is used for executing the translation pushing action of the piston rod; the spring steel is used for the resetting action of the piston rod; the box body is used for power transmission of the shifting fork for converting linear motion into torque output.

It should be noted that: the following description uses terms of orientation, all in accordance with the orientation shown in FIG. 2: the right end of the piston rod 5 extends into the cylinder body of the air cylinder 1, and the piston rod 5 and the piston 4 are coaxially and fixedly connected into a whole in the prior mode such as clamping limiting adaptation and coaxial screwing fastening. The utility model discloses characterized in that after the improvement: (as shown in fig. 2) the left end of the piston rod 5 passes through the box body 2 and then extends into the cylinder body of the spring cylinder 3 to be coaxially connected with the right end of the right spring seat 6 in an adjacent pushing manner. Namely, the piston rod 5 is not required to be fixedly connected with the right spring seat 6 into a whole by adopting an intermediate member, so that a wearing part is not needed, the processing of a connecting member can be omitted, and the number of parts is less. The structure is adopted, the assembly is simple and convenient, the requirement on the fit precision of the machining process size is low, the machining is easy, and the resetting transmission force of the axial moment of the compression spring is also reliable and practical while the structure is economical.

In addition, the left end of the right spring seat 6 is coaxially sleeved and fixedly connected with the right end of the compression spring 7; namely, the right end of the compression spring 7 is not required to be connected with the right spring seat 6 in a tight fit manner, and only the compression spring 7 needs to be sleeved in a clearance fit manner, so that the right end of the compression spring 7 can be sleeved with enough depth. By adopting the structure, the structure has the advantages of simple assembly and processing, economy and convenience.

In the same way: the left end of the compression spring 7 is coaxially sleeved and connected with the right end of the left spring seat 8, and the left end of the compression spring 7 is still ensured to have enough sleeving depth in the coaxial clearance fit sleeved mode on the right end of the left spring seat 8, so that the compression spring can be effectively prevented from losing efficacy. And further: the longitudinal sections of the left spring seat 8 and the right spring seat 6 are T-shaped; the T-shaped convex parts of the left spring seat 6 and the right spring seat 8 are arranged symmetrically and oppositely in the horizontal direction; the left end and the right end of the ring of the compression spring 7 are respectively sleeved and connected with the horizontal convex parts of the left spring seat 6 and the right spring seat 8 in a coaxial clearance fit manner. By adopting the structure, the structure has the advantages that the installation of the compression spring is simplified, and the exertion and the use of the axial resetting elastic function of the compression spring are not influenced.

In addition, the outer side of the seat body of the left spring seat 8 can be coaxially fastened and hermetically connected with the left shaft end of the cylinder body of the spring cylinder 3 by using a fastening assembly, and the installation of a fastening piece is not shown in the figure. Further: the compression spring 7 comprises a cylindrical, conical compression spring; the section of the spring body of the compression spring 7 is circular or rectangular so as to meet the deformation use requirements of the actuator on the shape of the compression spring in different environments.

For realizing the adaptability adjustment of the left limit of the piston rod: a horizontal axial threaded through hole 9 is formed in the axial center of the left spring seat 8; the threaded through hole 9 is coaxially screwed and matched with an adjusting bolt 101 in a matching way; the adjusting bolt 101 nut is arranged outside the cylinder body, and the screw rod extends into the cylinder body to axially adjust and limit the left limit of the piston rod 5 and the right spring seat 6. Compared with the hydraulic adjusting mode of the plunger cylinder plunger pump, the hydraulic adjusting device has the advantages of simple structure, simplicity in processing, convenience in adjustment, economy and practicability. Preferably: the thread through hole 9 and the thread profile of the adjusting bolt 101 are rectangular or trapezoidal. By adopting the tooth-shaped structure, when the adjusting bolt realizes the limiting adjustment through rotating, the adjusting bolt has the advantage of ensuring that the adjusting bolt has a more reliable limiting and retaining function.

To achieve power transfer from linear motion to torque power output: and the miniaturization design of power transmission is realized: the middle part of the rod body of the piston rod 5 is rotatably connected with the middle part of the rod body of the pin shaft 10 through a through hole; after the rod body of the pin shaft 10 vertically penetrates through the piston rod 5, the two ends of the pin shaft 10 are hinged with the lower end of a shifting fork 11 with an axisymmetric structure into a whole so as to realize the conversion and transmission of power through the rotation of the shifting fork. In the above embodiment, in order to realize the simple and reliable connection between the lower end opening end of the shift fork 11 and the two ends of the pin 10, (as shown in fig. 3), further: the pin shaft 10 is a cylindrical pin shaft; the end of the pin shaft is provided with an annular limiting groove 10-1 (see figure 7); a clamp spring 16 is fixedly sleeved in the annular limiting groove 10-1; before the clamp spring 16 is installed, the clamping sleeve 15 is sleeved at the shaft end of the pin shaft 10 in a clearance fit mode, then the clamping sleeve 15 is limited to be installed in an anti-falling mode at the shaft end of the pin shaft 10 through the clamp spring 16, and the rotation function of the clamping sleeve 15 relative to the pin shaft 10 is guaranteed. In addition, for realizing the reliable connection of cutting ferrule 15 and the lower extreme opening part of shift fork 11: the upper end face and the lower end face of the outer cylindrical surface of the sleeve body of the cutting sleeve 15 are respectively provided with an axisymmetric limiting clamping groove 15-1 (shown in figures 5 and 6), and the longitudinal section of the cutting sleeve 15 after being longitudinally cut at the position of the limiting clamping groove 15-1 is in an I-shaped structure (see figure 5); the upper limiting clamping groove 15-1 and the lower limiting clamping groove are axially symmetrical and arranged in parallel up and down; the limiting clamping groove 15-1 of the clamping sleeve 15 is inserted in a gap fit with the opening at the lower end of the fork body of the shifting fork 11 (see fig. 3), so that the opening at the lower end of the shifting fork 11 is connected with the pin shaft 10 in a wrenching and hinged mode into a whole. It should be understood that the cutting ferrule 15 is adapted to the insertion depth of the lower end opening end of the shifting fork 11, and it should be ensured that the lower end of the shifting fork 11 does not fall off when swinging clockwise and anticlockwise to the left and right extreme limit positions.

In addition, the upper end of the shifting fork 11 is fixedly connected with the middle part of the shaft body of the transmission shaft 13 through a positioning pin 12 (as shown in fig. 4) so as to pry the transmission shaft 13 to rotate through the rotation of the upper end of the shifting fork, thereby outputting torque. Further: for compact miniaturized transmission structure: the shifting fork 11 is a U-shaped axisymmetric double-fork-head shifting fork structure (see fig. 3), and the U-shaped closed end of the shifting fork is a solid block structure with a certain thickness so as to ensure structural rigidity. And the body block of the solid body is provided with a jack 11-1 at the axial symmetry center (see figure 2); the jack 11-1 is in clearance fit with one end of the plug-in positioning pin 12, but enough insertion depth is ensured; the other end of the positioning pin 12 can also be inserted into a through hole formed in the middle of the shaft body of the transmission shaft 13 in a clearance fit manner (see fig. 4); to ensure large torque output: the depth of the positioning pin 12 inserted into the insertion hole 11-1 is greater than the depth of the positioning pin 12 inserted into the transmission shaft 13, and the depth of the insertion hole 11-1 is greater than one half of the axial length of the positioning pin 12, namely, the lever principle is utilized to realize the high-torque prying transmission output of the positioning pin 12 to the transmission shaft 13. Namely, the shift fork 11 pries the transmission shaft 13 to rotate through the positioning pin 12 to output torque. The prying type transmission structure of the axisymmetric shifting fork has the advantages of simple and compact structure, contribution to miniaturization design and realization of large torque output; simple and compact structure but high transmission speed and efficiency.

In addition, two ends of the transmission shaft 13 are supported by shaft sleeves 14 which are arranged in an axisymmetric manner and are rotatably supported and installed on the box body 2; preferably: the shaft sleeve 14 is a copper shaft sleeve with a self-lubricating function; and the boss 14 has a T-shaped configuration in longitudinal section (see fig. 4). The structure and the material have the advantages of simple structure and capability of realizing the self-lubricating function of the shaft sleeve. In the above embodiment, to improve the reliability of the large torque output of the propeller shaft, further: an annular groove I14-1 is formed at the fixed matching position of the outer cylindrical surface of the sleeve body of the shaft sleeve 14 and the box body 2, and a rectangular section sealing ring is arranged in the annular groove I14-1; an annular groove II 13-1 is formed at the rotating matching position of the outer cylindrical surface of the shaft end of the transmission shaft 13 and the shaft sleeve 14; and a rectangular section sealing ring is arranged in the annular groove II 13-1.

Furthermore, the utility model discloses a 1 cylinder body inside wall of cylinder is equipped with the PTFE coating. The inner wall of the cylinder 1 of the utility model adopts the PTFE (polytetrafluoroethylene) coating design; the PTFE (polytetrafluoroethylene) coating can be continuously used at 260 ℃, and has the highest use temperature of 290 ℃ and 300 ℃, extremely low friction coefficient, good wear resistance and excellent chemical stability; the surface smoothness of the movement of the cylinder piston is increased, the friction force is greatly reduced, and the corrosion resistance is realized; the transmission of the miniature shifting fork is cooperated; the high-efficiency output capacity of the torque of the actuator is improved, the reaction speed of the actuator is improved, and the 90-degree opening and closing are efficient, reliable and rapid.

The working principle is as follows: as shown in fig. 2, after the cylinder 1 is inflated, the piston 4 pushes the piston rod 5 coaxially and fixedly connected with the piston 4 to move horizontally leftwards; when the piston rod 5 moves leftwards, the shaft end of the left end of the piston rod 5 is adjacent to a right spring seat 6 which is pushed to a T-shaped structure and moves leftwards; the left end of the right spring seat 6 is compressed by a compression spring 7 which is in clearance fit with the T-shaped bulge and is coaxially sleeved and installed; in the process, the shifting fork 11 hinged to the middle part of the piston rod 5 through the pin shaft 10 pushes the shifting fork 11 to rotate clockwise (in the direction shown in fig. 3); when the shifting fork 11 rotates clockwise, like a spanner with a symmetrical structure, the positioning pin 12 fixedly connected with the upper end of the shifting fork 11 in an inserted manner pries the transmission shaft 13 fixedly connected with the other end of the positioning pin 12 to output a 90-degree rotation torque; the aim that the linear motion of the piston rod of the air cylinder is converted into the 90-degree torque output of the transmission shaft by the pneumatic actuator is achieved. Otherwise; when the cylinder 1 stops performing the action; the piston rod 5 is urged to move to the right (in the direction shown in fig. 2) by the return spring force of the compression spring 7. At the same time; the 90-degree torque output limit of the actuator transmission shaft 13 is adjusted by directly rotating an adjusting bolt 101 coaxially screwed in the center of the left spring seat 8. Namely, by turning the adjusting bolt 101, the adjusting bolt 101 realizes the axial left-right displacement adjustment, so as to limit the left end limit position of the piston rod 5, and accordingly: the limiting adjustment of the rotation limit position of the shifting fork and the torque output limit position of the transmission shaft 13 is realized. The structure is simple and compact, the volume is small, the transmission is high-efficiency, the installation is convenient, the assembly and the adjustment are convenient, and the device is economical and practical.

Compared with the prior art: the utility model discloses a no matter torque output mechanism, still torque output limit position adjustment mechanism, the pneumatic actuator of single-action shift fork that all is more simple. The actuator can realize convenient installation of the shifting fork, reduce the transmission cost of the shifting fork and miniaturize the space volume occupied by the shifting fork transmission structure; the friction resistance can be greatly reduced by cooperating with the design of the cylinder PTFE coating; the high-efficiency miniaturized shifting fork transmission structure not only improves the reaction speed of the actuator; the actuator design of realizing large torque power output by low thrust and being more economical, practical and efficient is further realized; therefore, the product has the advantages of excellent universality, economy, practicability, cost performance advantage and market competitiveness.

From the above description it can be found that: the utility model adopts the reset elasticity of the compression spring to realize the reset of the piston rod of the pneumatic actuating mechanism; compared with an extension spring, the transmission structure is simpler, the assembly of the spring and the spring seat is more convenient, and the high-efficiency transmission of axial torque can be realized without fastening and connecting the spring and the spring seat into a whole; the processing of the connecting parts is omitted, and the processing difficulty of the parts is greatly reduced; moreover, the structure of the compression spring is more varied, and the compression spring can be more possibly subjected to appropriate modification design according to the change of the environment; the universality is more ideal.

Secondly, the spring seat of the utility model is provided with an adjusting bolt after the screw thread is drilled to realize the adaptability adjustment of the extreme position of the piston rod; compared with a plunger type design structure, the structure is simpler, the process precision requirement is lower, the structure is simplified, and the realization is easier; the adjustment operation of the limit position is simple and convenient, so that the device is more economical and practical; the lower rectangular or trapezoidal teeth have more reliable limit and backstop functions; the device has the advantages of economical and practical structural design, stability and reliability.

Furthermore, the shifting fork actuating mechanism of the utility model adopts an axisymmetric structure and combines a lever type prying principle to realize torque transmission; the structure is compact, and the volume is small; but also has the advantages of more labor-saving, reliable and efficient transmission; the large-torque 90-degree power output can be realized.

Moreover, the shaft sleeve 14 with the copper T-shaped structure of the utility model, in cooperation with the sealing ring, realizes the self-lubricating function of the transmission shaft; and simultaneously, the torque is reliably and stably output. Moreover, the U-shaped axisymmetric double-fork structure; the structure is compact, and the volume is small; the transmission is efficient, stable and rapid; the torque output of the transmission shaft is realized by adopting a lever type prying mode; the positioning pin 12 is inserted and installed to realize prying type torque output transmission connection between the positioning pin 12 and the top end of the shifting fork 11 and the middle part of the transmission shaft 13; the requirement on the dimensional matching precision is low; simple structure, convenient assembly, economy, practicality, small size and high efficiency.

In summary, the utility model has the advantages of simple structure, compact design, small volume, modular assembly, simple and convenient assembly and processing, and convenient operation; the transmission has the advantages of quick response, stable, reliable and efficient transmission, capability of realizing large-torque output and comprehensive advantage of economical efficiency, practicability and optimal cost performance.

It is obvious to a person skilled in the art that the invention is not restricted to details of the above-described exemplary embodiments, but that it can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

The above-mentioned embodiments are merely preferred embodiments of the present invention, and not intended to limit the scope of the present invention, so that all equivalent changes made by the contents of the claims of the present invention should be included in the scope of the claims of the present invention.

Claims

1. The single-action shifting fork type pneumatic actuator comprises a cylinder (1), a box body (2), a spring cylinder (3), a piston (4), a piston rod (5) and a spring seat; the piston (4) is installed in the cylinder (1), and the right end of the piston rod (5) extends into the cylinder body of the cylinder (1) and is coaxially and fixedly connected with the piston (4); the method is characterized in that: the left end of the piston rod (5) penetrates through the box body (2) and then extends into the cylinder body of the spring cylinder (3) to be coaxially connected with the right end of the right spring seat (6) in a pushing mode; the left end of the right spring seat (6) is coaxially sleeved and fixedly connected with the right end of the compression spring (7); the left end of the compression spring (7) is coaxially sleeved and connected with the right end of the left spring seat (8); the outer side of the seat body of the left spring seat (8) is coaxially and hermetically fixedly connected with the left end of the cylinder body of the spring cylinder (3) into a whole; a horizontal axial threaded through hole (9) is formed in the axial center of the left spring seat (8); the threaded through hole (9) is coaxially screwed with an adjusting bolt (101) in a matching manner; the adjusting bolt (101) is arranged outside the cylinder body, and the screw rod extends into the cylinder body to axially adjust and limit the left limit of the piston rod (5) and the right spring seat (6); the middle part of the rod body of the piston rod (5) is hinged with the middle part of the rod body of the pin shaft (10); two ends of the pin shaft (10) are hinged with the lower ends of the shifting forks (11) with the axisymmetric structures; the upper end of the shifting fork (11) is fixedly connected with the middle part of a shaft body of the transmission shaft (13) through a positioning pin (12), and torque is output through the transmission shaft (13); two ends of the transmission shaft (13) are rotatably supported and installed on the box body (2) through shaft sleeves (14) which are arranged in an axisymmetric manner; and the inner side wall of the cylinder body of the cylinder (1) is provided with a PTFE coating.

2. The single-acting fork pneumatic actuator of claim 1, wherein: the compression spring (7) comprises a cylindrical, conical compression spring; the cross section of the spring body of the compression spring (7) is circular or rectangular.

3. The single-acting fork pneumatic actuator of claim 1, wherein: the longitudinal sections of the left spring seat (8) and the right spring seat (6) are T-shaped; the left and right horizontal shafts of the left and right T-shaped horizontal convex parts of the left and right spring seats (6, 8) are symmetrically and oppositely arranged; the left end and the right end of the ring of the compression spring (7) are respectively sleeved and connected with the horizontal convex parts of the left spring seat (6) and the right spring seat (8) in a coaxial clearance fit manner.

4. The single-acting fork pneumatic actuator of claim 1, wherein: the thread through hole (9) and the thread profile of the adjusting bolt (101) are rectangular or trapezoidal.

5. The single-acting fork pneumatic actuator of claim 1, wherein: the shaft sleeve (14) is a copper shaft sleeve with a self-lubricating function; and the longitudinal section of the shaft sleeve (14) is of a T-shaped structure.

6. The single-acting fork pneumatic actuator of claim 1, wherein: two ends of the pin shaft (10) are axially limited and blocked by shaft end clamp springs (16) on two ends of the pin shaft (10), and clamp sleeves (15) which are in a circular ring structure and are in clearance fit and rotating installation are arranged on the two ends of the pin shaft (10); the upper end face and the lower end face of the outer cylindrical surface of the sleeve body of the cutting sleeve (15) are respectively provided with an axisymmetric limiting clamping groove (15-1), and the section of the cutting sleeve (15) after being longitudinally cut at the position of the limiting clamping groove (15-1) is in an I-shaped structure; the upper limiting clamping groove and the lower limiting clamping groove (15-1) are axially symmetrical and arranged in parallel up and down; the limiting clamping groove (15-1) of the clamping sleeve (15) is in adaptive insertion connection with the gap of the lower end opening of the fork body of the shifting fork (11) so as to pull and hinge the lower end opening of the shifting fork (11) and the pin shaft (10) into a whole.

7. The single-acting fork pneumatic actuator of claim 1, wherein: an annular groove I (14-1) is formed at the fixed matching position of the outer cylindrical surface of the sleeve body of the shaft sleeve (14) and the box body (2), and a rectangular section sealing ring is arranged in the annular groove I (14-1); an annular groove II (13-1) is formed at the rotating fit position of the outer cylindrical surface of the shaft end of the transmission shaft (13) and the shaft sleeve (14); and a rectangular section sealing ring is arranged in the annular groove II (13-1).

8. The single-acting fork pneumatic actuator of claim 1, wherein: the shifting fork (11) is of a U-shaped axisymmetric double-fork-head shifting fork structure, the U-shaped closed end of the shifting fork is of a solid block structure with a certain thickness, and the axisymmetric center of the solid block is provided with a jack (11-1); the jack (11-1) is in adaptive insertion connection with one end of the positioning pin (12); the other end of the positioning pin (12) is matched with a through hole formed in the middle of the shaft body of the plug-in transmission shaft (13); the shifting fork (11) prizes the transmission shaft (13) to rotate through the positioning pin (12) so as to output torque; the depth of the positioning pin (12) inserted into the insertion hole (11-1) is larger than that of the positioning pin (12) inserted into the transmission shaft (13), and the depth of the insertion hole (11-1) is larger than one half of the axial length of the positioning pin (12).