Shifting fork type executing mechanism

Abstract

The invention relates to a shifting fork type executing mechanism which comprises a cylinder body, end covers are further arranged at the two ends of the cylinder body, a piston and a shifting fork disc are arranged in the cylinder body, and the piston and the shifting fork disc are connected through a locking assembly. The surface of the shifting fork disc is further provided with a centrosymmetric U-shaped groove. The U-shaped groove in the shifting fork disc is eccentric and inclined relative to the center shaft of the shifting fork disc after being tested, in the process that the shifting fork disc moves back and forth along with the piston, the U-shaped groove opening of the pulling and inserting disc can make contact with the pin shaft and the shaft sleeve to generate torque, and the pin shaft and the shaft sleeve are inserted into the U-shaped groove opening at the end of the movement stroke of the piston. And the difference between the generated maximum torque and the generated minimum torque is effectively reduced while parts of an executing mechanism do not interfere with the movement of the piston, so that the service life of the shifting fork disc is prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of actuators, and in particular to a scotch fork type actuator. Background Art

[0002] Actuators, as a device that can generate linear or rotary motion, are used to control or drive other mechanical parts. The technical field to which they belong is relatively broad. In particular, fork-type actuators, their working principle is mainly to push the piston to perform linear motion. The piston is connected to the slot of the fork through the piston pin, converting the linear motion of the piston into the rotary motion of the fork. The rotation of the fork further drives the rotation of the output shaft, thereby achieving precise control of industrial equipment.

[0003] However, the traditional scotch fork actuator still has the following problems in actual use: (1) In traditional actuators, when the fork plate moves back and forth with the piston, the slot of the pull-out plate will generate torque, especially at the end points of the piston's movement. If the torque generated at the end points is too large, the service life of the fork plate will be reduced.

[0004] (ii) In traditional actuators, the connection between the piston and the plug-in plate is a threaded connection through a pin shaft. After long-term use, this connection method will inevitably cause the threaded connection to loosen, affecting the operation of the mechanism and even causing the pin shaft to fall off, resulting in damage to the mechanism. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, an object of the present invention is to provide a scotch fork actuator to solve one or more problems in the prior art.

[0006] To achieve the above object, the technical solution of the present invention is as follows: A fork-type actuator comprises a cylinder body, end covers are arranged at both ends of the cylinder body, a piston and a fork disc are arranged in the cylinder body, the piston and the fork disc are connected by a locking assembly; a centrally symmetrical U-shaped groove is also arranged on the surface of the fork disc.

[0007] Furthermore, compared with being symmetrically arranged with respect to the central axis of the fork disc, the U-shaped groove is offset from the central axis of the fork disc by 2 mm and is arranged obliquely with respect to the direction of the central axis of the fork disc.

[0008] Furthermore, the central axis of the U-shaped groove and the central axis of the fork plate form an angle of 12° in the same plane.

[0009] Furthermore, a clamping rod is arranged on a side of the piston close to the fork plate, and the fork plate is arranged between the clamping rods.

[0010] Furthermore, the locking assembly includes a pin shaft, a first hole is opened on the surface of the clamping rod, and the pin shaft is arranged in the U-shaped groove through the first hole.

[0011] Furthermore, the pin shaft is interference fit in the first hole.

[0012] Furthermore, the locking assembly also includes a sleeve, which is sleeved on the portion of the pin located between the clamping rods.

[0013] Furthermore, the shaft sleeve can be movably matched with the groove surface of the U-shaped groove.

[0014] Furthermore, the fork plate is also provided with a second hole, and protrusions are evenly arranged along the second hole.

[0015] Furthermore, a driving shaft is also arranged in the cylinder body, and recessed parts are evenly arranged on the surface of the driving shaft, and the recessed parts are matched with the protruding parts.

[0016] Compared with the prior art, the beneficial technical effects of the present invention are as follows: (I) After testing, the U-shaped groove on the fork plate of the present invention is eccentric and oblique compared to the central axis of the fork plate. When the fork plate moves back and forth with the piston, the U-shaped groove of the plug-in plate will contact the pin shaft and the sleeve to generate torque. At the end of the piston movement stroke, while ensuring that the actuator parts do not interfere with the piston movement, the difference between the maximum torque and the minimum torque generated is effectively reduced, thereby increasing the service life of the fork plate.

[0017] (ii) In the present invention, the connection between the piston and the plug-in disk is achieved by an interference fit. When subjected to heavy loads or impact loads, the interference fit can provide a more stable connection. This connection method avoids, to a certain extent, the loosening of the traditional threaded connection, which affects the operation of the mechanism and even causes the pin shaft to fall off, resulting in damage to the mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 The overall structural diagram of a scotch fork type actuator according to an embodiment of the present invention is shown.

[0019] Figure 2 The structure diagram of a fork plate of a fork-type actuator according to an embodiment of the present invention is shown. Figure Ⅰ .

[0020] Figure 3 The structure diagram of a fork plate of a fork-type actuator according to an embodiment of the present invention is shown. Figure II .

[0021] Figure 4 A schematic structural diagram of a piston of a scotch fork type actuator according to an embodiment of the present invention is shown.

[0022] Figure 5 A schematic diagram of the structure inside a cylinder of a scotch fork type actuator according to an embodiment of the present invention is shown.

[0023] Figure 6 An enlarged structural diagram of a locking assembly of a scotch fork type actuator according to an embodiment of the present invention is shown.

[0024] Markings in the accompanying drawings: 1, cylinder body; 2, end cover; 3, piston; 301, clamping rod; 3011, first hole; 4, fork plate; 401, U-shaped groove; 402, second hole; 4021, protrusion; 5, locking assembly; 501, pin shaft; 502, bushing; 6, driving shaft; 601, recessed portion. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the present invention clearer, a fork-type actuator proposed by the present invention is further described in detail below in combination with the accompanying drawings and specific implementation methods. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the accompanying drawings are in a very simplified form and use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the implementation method of the present invention. In order to make the purpose, features and advantages of the present invention more obvious and easy to understand, please refer to the accompanying drawings. It should be noted that the structure, proportion, size, etc. illustrated in the drawings of 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 for the implementation of the present invention, so they have no technical substantive significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effect that the present invention can produce and the purpose that can be achieved, should still fall within the scope of the technical content disclosed by the present invention.

[0026] See also Figures 1 to 6 The fork-type actuator of this embodiment includes a cylinder body 1, end covers 2 are also provided at both ends of the cylinder body 1, a piston 3 and a fork plate 4 are provided in the cylinder body 1, two pistons 3 are provided in this embodiment, the piston 3 and the fork plate 4 are connected by a locking assembly 5, and a centrally symmetrical U-shaped groove 401 is also provided on the surface of the fork plate 4. In this embodiment, two U-shaped grooves 401 are provided on the surface of the fork plate 4.

[0027] Furthermore, the U-shaped groove 401 is offset from the central axis of the fork plate 4 by 2 mm and is obliquely arranged relative to the central axis of the fork plate 4, compared to being symmetrically arranged with respect to the central axis of the fork plate 4. The central axis of the U-shaped groove 401 forms an angle of 12° with the central axis of the fork plate 4 in the same plane. The offset distance and the oblique angle are obtained by testing different stages of the movement of the pin 501 and the sleeve 502 by the piston 3 in the U-shaped groove 401. Considering the interference between the piston 3 and the sleeve 502 and the difference in the extreme values ​​of the torque at the end points of the movement, for the embodiment of the present invention, it is required that the torque difference between 0° and 90° of the rotational movement of the fork plate 4 relative to the driving shaft 6 is ≥15%.

[0028] Specifically, it is shown in the following Table 1: Table 1

[0029] According to the above Table 1, the U-shaped groove 401 is tested at different angles relative to the driving shaft 6 by trial and error under the condition of constant offset and offset angle. Finally, the scheme of offsetting 2 mm and deflecting 12° in this embodiment is selected according to the interference amount and torque difference. Specifically, the analysis and judgment are as follows: Solution 1: The torque difference between 0° and 90° is too large, and the interference at 0° is too large, so it is not considered.

[0030] Solution 2: The torque difference between 0° and 90° is small and does not meet the 15% difference required by the present invention, so it is not considered.

[0031] Option 3: The torque difference between 0° and 90° is relatively large, but the interference at the 0° position is too large and is not considered.

[0032] Solution 4: The torque difference between 0° and 90° is too large, and the interference at 0° is too large, so it is not considered.

[0033] Solution 5: The torque difference between 0° and 90° is too large. Although there is no interference, it is easy to affect the accuracy and service life, so it is not considered as the preferred solution.

[0034] Solution 6: If the torque difference between 0° and 90° is ≥15% and there is no interference, consider this method.

[0035] Furthermore, the piston 3 is provided with a clamping rod 301 on a side close to the fork plate 4 . In the present embodiment, each of the pistons 3 has two clamping rods 301 , and the fork plate 4 is provided between the clamping rods 301 .

[0036] Furthermore, the locking assembly 5 includes a pin 501, a first hole 3011 is provided on the surface of the clamping rod 301, and the pin 501 is arranged in the U-shaped groove 401 through the first hole 3011, so that the clamping rod 301 can push the fork plate 4 to move. The pin 501 is interference-fitted in the first hole 3011, thereby improving the connection between the clamping rod 301 and the fork plate 4, and reducing the risk of loosening caused by the traditional threaded connection after long-term use. The effectiveness of the connection between the pin 501 and the clamping rod 301 can also be further ensured by adding auxiliary components such as a retaining spring.

[0037] Furthermore, the locking assembly 5 also includes a sleeve 502, and the sleeve 502 is sleeved on the portion of the pin 501 between the clamping rods 301. The sleeve 502 can be movably matched with the groove surface of the U-shaped groove 401. As the piston 3 drives the clamping rod 301 to move, the sleeve 502 moves on the groove surface of the U-shaped groove 401 along with the pin 501 under the action of the clamping rod 301. Based on the arrangement of the U-shaped groove 401 on the surface of the fork plate 4, it can be ensured that under the movement path of the piston 3, the pin 501 and the sleeve 502 will never be separated from the U-shaped groove 401 within a certain service life, and will not interfere with the piston 3.

[0038] Furthermore, the fork plate 4 is also provided with a second hole 402, and protrusions 4021 are evenly arranged along the second hole 402. A driving shaft 6 is also arranged in the cylinder body 1, and a recessed portion 601 is evenly arranged on the surface of the driving shaft 6. The recessed portion 601 cooperates with the protrusion 4021. When the piston 3 pushes the fork plate 4 to rotate, the driving shaft 6 rotates with the rotation of the fork plate 4 to achieve the output of the movement. Through the cooperation between the protrusion 4021 and the recessed portion 601, the phenomenon of the driving shaft 6 and the fork plate 4 being unable to bite due to wear during long-term movement is effectively avoided.

[0039] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0040] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A scotch fork actuator, comprising a cylinder body, end covers are provided at both ends of the cylinder body, and is characterized in that: A piston and a fork plate are arranged in the cylinder body, and the piston and the fork plate are connected via a locking assembly; a centrally symmetrical U-shaped groove is also arranged on the surface of the fork plate.

2. A scotch fork actuator according to claim 1, characterized in that: Compared with the U-shaped groove being symmetrically arranged with respect to the central axis of the fork disc, the U-shaped groove is offset from the central axis of the fork disc by 2 mm and is arranged obliquely with respect to the direction of the central axis of the fork disc.

3. A scotch fork actuator as claimed in claim 2, characterized in that: The central axis of the U-shaped groove and the central axis of the fork plate form an angle of 12° in the same plane.

4. A scotch fork actuator as claimed in claim 3, characterized in that: The piston is provided with a clamping rod on one side close to the fork disc, and the fork disc is arranged between the clamping rods.

5. A scotch fork actuator as claimed in claim 4, characterized in that: The locking assembly includes a pin shaft, a first hole is provided on the surface of the clamping rod, and the pin shaft is arranged in the U-shaped groove through the first hole.

6. A scotch fork actuator as claimed in claim 5, characterized in that: The pin shaft is interference fit in the first hole.

7. A scotch fork actuator according to claim 6, characterized in that: The locking assembly also includes a sleeve, which is externally mounted on the portion of the pin located between the clamping rods.

8. A scotch fork actuator according to claim 7, characterized in that: The shaft sleeve can be movably matched with the groove surface of the U-shaped groove.

9. A scotch fork actuator according to claim 8, characterized in that: The fork plate is also provided with a second hole, and protrusions are evenly arranged along the second hole.

10. A scotch fork actuator according to claim 9, characterized in that: A driving shaft is also arranged in the cylinder body, and recessed parts are evenly arranged on the surface of the driving shaft, and the recessed parts are matched with the protruding parts.

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