Transmission mechanism for linkage of valve body mechanism

Abstract

The utility model provides a transmission mechanism for linkage of a valve body mechanism, and relates to the technical field of valve pneumatic actuators. The two connecting rods are connected through a connecting assembly to form a flexible connection state; the connecting rod adopting conventional rigid connection is prevented from being damaged due to the fact that the pneumatic actuator acts quickly and the instant impact of the initial action is very large, and the risk of breakage of the connecting rod is avoided; according to the structure, the endurance capacity of the equipment is improved, real-time feedback is provided for transmission of the positioner and the limiting switch, and the problem that the use experience of a user is affected due to the hysteresis phenomenon of synchronization of the limiting switch and the positioner in the front half section of transmission is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of valve pneumatic actuators, in particular to a transmission mechanism used for the linkage of a valve body mechanism. Background Art

[0002] Pneumatic control valves are widely used in chemical, petroleum and other industries. Under normal operating conditions, the control valve only uses one positioner, and the valve opening is controlled by adjusting the size of the positioner's electrical signal.

[0003] At present, some users have proposed that in addition to the valve opening adjustment function, the switch position synchronous feedback function is also required. Therefore, in the prior art, the quarter-turn valve often uses a synchronous action mechanism of the positioner and the limit switch to realize the linkage between the two. Most of the structures adopt the fork type. The above mechanism realizes control through the cooperation of the fork and the slide. During operation, the fork method is easy to disengage from the slide, causing the entire actuator to fail to work; and the linkage between the limit switch and the positioner in the first half of the mechanism action is not synchronized, and there is a hysteresis phenomenon, which seriously affects the user's use needs; and the above transmission method generates a large impact force on the valve body, which easily causes the risk of valve body damage.

[0004] In view of this, a structure that meets the above requirements is needed to meet the needs of users. Utility Model Content

[0005] The purpose of the utility model is to provide a transmission mechanism for valve body mechanism linkage, which can solve the problems raised by the above-mentioned background technology in view of the shortcomings of the prior art.

[0006] The technical solution of the utility model is achieved in this way:

[0007] The utility model provides a transmission mechanism for valve body mechanism linkage, comprising two connecting rods detachably connected to a positioner and a limit switch respectively, and a connecting assembly for flexibly connecting the positioner and the limit switch is arranged between the two connecting rods.

[0008] In some technical solutions of the utility model, the connecting assembly includes a box body, a buffer spring is arranged in the box body, and the two connecting rods are slidably arranged in the box body and abut against the buffer spring.

[0009] In some technical solutions of the utility model, the box body includes an upper box body and a lower box body, and the upper box body and the lower box body are detachably connected.

[0010] In some technical solutions of the utility model, both ends of the box body are provided with a first sliding bearing slidably connected to the connecting rod.

[0011] In some technical solutions of the utility model, a top plate is provided at one end of the connecting rod abutting against the buffer spring.

[0012] In some technical schemes of the utility model, two connecting rod heads are further included which are detachably connected to the two connecting rods respectively, and the connecting rod heads are provided with locking nuts which are threadedly connected to the connecting rods. A first fixing component is provided between one of the connecting rod heads and the locator; and a second fixing component is provided between the other connecting rod head and the limit switch.

[0013] In some technical schemes of the utility model, the first fixing component includes a square hole rocker arm rotatably connected to the connecting rod head, the output end of the positioner is inserted into the square hole of the square hole rocker arm, an installation hole is opened on the outer side wall of the square hole rocker arm, and a screw threadedly connected to the output end of the positioner is provided in the installation hole.

[0014] In some technical schemes of the utility model, the second fixed component includes a clamping block rocker arm connected to the connecting rod head pin, a feedback rod and a fastener. The feedback rod is inserted in the clamping area of ​​the clamping block rocker arm and fixed by the fastener. A bearing seat is provided on the feedback rod. A second sliding bearing is provided between the bearing seat and the feedback rod. The bearing seat is fixed on the bracket of the limit switch, and the feedback rod is transmission connected to the input end of the limit switch.

[0015] Compared with the prior art, the embodiments of the present invention have at least the following advantages or beneficial effects:

[0016] The two connecting rods are connected by a connecting assembly to form a flexible connection state; this can avoid the rapid action of the pneumatic actuator and the great impact at the moment of the initial action, which may damage the connecting rod with a conventional rigid connection and avoid the risk of connecting rod breakage; the above structure improves the tolerance of the equipment, provides real-time feedback for the positioner and limit switch transmission, and avoids the hysteresis phenomenon in the synchronization of the limit switch and the positioner in the first half of the transmission, which affects the user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 This is the structural intention of the general assembly front view of the utility model;

[0019] Figure 2 It is a schematic diagram of the general assembly side structure of the utility model;

[0020] Figure 3 It is a three-dimensional structural schematic diagram of the connecting rod and the connecting assembly in the utility model;

[0021] Figure 4 for Figure 1 Schematic diagram of the cross-sectional structure along the AA direction;

[0022] Figure 5 for Figure 4 Schematic diagram of the cross-sectional structure along the middle BB direction;

[0023] Figure 6 for Figure 4 Schematic diagram of the cross-sectional structure in the CC direction;

[0024] Figure 7 for Figure 5 Schematic diagram of the cross-sectional structure along the DD direction.

[0025] Icons: 1. Pneumatic head; 2. Pneumatic head bracket; 3. Positioner bracket; 4. Positioner; 5. Limit switch; 6. Limit switch bracket; 7. Screw; 8. Square hole rocker arm; 9. Clamp rocker arm; 10. Fastener; 11. Cotter pin; 12. Pin shaft; 13. Connecting rod head; 14. Locking nut; 15. Connecting rod; 16. First sliding bearing; 17. Buffer spring; 18. Lower housing; 19. Second sliding bearing; 20. Upper housing; 21. Bearing seat; 23. Feedback lever; 24. Hexagon screw. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Example 1

[0029] Please refer to Figure 1-Figure 7 shown.

[0030] The utility model provides a transmission mechanism for valve body mechanism linkage, such as Figure 1 , Figure 2As shown, the utility model provides a transmission mechanism for the linkage of the valve body mechanism, including two connecting rods 15 detachably connected to the positioner 4 and the limit switch 5, respectively, and a connecting assembly for flexibly connecting the positioner 4 and the limit switch 5 is provided between the two connecting rods 15. The two connecting rods 15 are connected by a connecting assembly to form a flexible connection state; it can avoid the damage to the connecting rod 15 with conventional rigid connection caused by the rapid action of the pneumatic actuator and the great impact at the moment of the initial action, and avoid the risk of the connecting rod 15 breaking; the above structure improves the tolerance of the device, provides real-time feedback for the transmission of the positioner 4 and the limit switch 5, and avoids the hysteresis phenomenon of the synchronization of the limit switch 5 and the positioner 4 in the first half of the transmission, which affects the user's experience.

[0031] Preferably, the positioner 4 and the limit switch 5 are both installed on the pneumatic head 1 through the pneumatic head bracket 2.

[0032] In some technical solutions of the utility model, the connecting assembly includes a box body, a buffer spring 17 is arranged in the box body, and the two connecting rods 15 are slidably arranged in the box body and abut against the buffer spring 17. The buffer spring 17 is arranged in the box body, and when the two connecting rods 15 are subjected to force transmission, the buffer spring 17 disposed between the two connecting rods 15 is squeezed, which can effectively offset the instantaneous impact force of the cylinder, improve the force condition of the connecting rod 15, and reduce the risk of the connecting rod 15 being damaged; and through the above structure, the transmission of the cylinder is continuous, and the limit switch 5 and the positioner 4 are synchronously moved.

[0033] In some technical solutions of the utility model, the box body includes an upper box body and a lower box body, and the upper box body and the lower box body are detachably connected. The box body is divided into an upper box body and a lower box body, which is convenient for installing the buffer spring 17, convenient for disassembly and convenient for later maintenance.

[0034] Preferably, the upper box body and the lower box body are fastened by four countersunk screws 7 .

[0035] In some technical solutions of the utility model, both ends of the box body are provided with a first sliding bearing 16 which is slidably connected to the connecting rod 15. This prevents the friction between the box body and the connecting rod 15 from increasing when they are in contact, hindering the speed at which the connecting rod 15 releases the instantaneous impact force of the cylinder by squeezing during transmission, causing the connecting rod 15 to be subjected to a greater force after being subjected to the instantaneous impact force of the cylinder, resulting in the risk of the connecting rod 15 being broken after fatigue.

[0036] In some technical solutions of the utility model, a top plate is provided at one end of the connecting rod 15 that abuts against the buffer spring 17. The top plate is integrally formed with the connecting rod 15 through a turning process, which can increase the contact area between the connecting rod 15 and the buffer spring 17 and better release the instantaneous impact force applied by the cylinder thereto; and when the top plate moves in the slideway in the box body, it can also play a limiting role to prevent the connecting rod 15 from falling off from the box body and affecting the service life of the contact.

[0037] In some technical schemes of the utility model, two connecting rod heads 13 are detachably connected to two connecting rods 15 respectively, and locking nuts 14 are provided on the connecting rod heads 13 and are threadedly connected to the connecting rods 15. A first fixing assembly is provided between one connecting rod head 13 and the positioner 4; and a second fixing assembly is provided between the other connecting rod head 13 and the limit switch 5. By setting a U-shaped connecting rod head 13 to connect with the connecting rod 15, and the connecting rod 15 is threadedly connected with the internal threaded hole provided at the bottom of the connecting rod head 13, the length of the connecting rod 15 is adjustable, and the connecting rod 15 can be installed according to the actual working conditions; the locking nut 14 is a hexagonal nut, which is screwed in from the external thread section on the connecting rod 15 toward the direction close to the connecting head until the locking nut 14 abuts against the connecting rod head 13, so as to lock the connecting rod head 13 and the connecting rod 15 and prevent the two from loosening. By setting the second fixing assembly and the first fixing assembly, the corresponding connecting head and the positioner 4 and the limit switch 5 can be quickly assembled, and it is also convenient to disassemble and maintain the above structure at a later time.

[0038] In some technical solutions of the utility model, the first fixing assembly includes a square hole rocker arm 8 rotatably connected to the connecting rod head 13, the output end of the positioner 4 is inserted into the square hole of the square hole rocker arm 8 and adapted thereto, a mounting hole is provided on the outer side wall of the square hole rocker arm 8, and a screw 7 threadedly connected to the output end of the positioner 4 is provided in the mounting hole. The screw 7 is a statically set screw 7, and the connection between the square hole rocker arm 8 and the output end of the positioner 4 through the above structure can prevent the square hole rocker arm 8 from moving, and avoid its movement affecting the transmission accuracy of the cylinder.

[0039] In some technical solutions of the utility model, the second fixing assembly includes a clamping block rocker arm 9 connected to the connecting rod head 13 by a pin, a feedback rod 23 and a fastener 10. The feedback rod 23 is inserted in the clamping area of ​​the clamping block rocker arm 9 and fixed by the fastener 10. The fastener 10 is a hexagon socket screw 24. A bearing seat 21 is provided on the feedback rod 23. A second sliding bearing 19 is provided between the bearing seat 21 and the feedback rod 23. The bearing seat 21 is fixed to the bracket of the limit switch 5. The feedback rod 23 is connected to the input end of the limit switch 5 by transmission. The clamping block rocker arm 9 is fastened by the hexagon socket screw 24. The feedback rod 23 is clamped by the friction force generated by the clamping force of the clamping block rocker arm 9 on the feedback rod 23 to achieve a fixing effect. The clamping block structure has a high tolerance to assembly errors, which is conducive to improving assembly efficiency and reducing labor intensity.

[0040] The feedback rod 23 is connected to the limit switch 5 through the bearing seat 21, and the bearing seat 21 is fixed to the limit switch bracket 6 by screws 7 to avoid deformation caused by welding and facilitate replacement. A sliding bearing is installed in the bearing seat 21 to reduce the friction of the feedback rod 23, prevent strain, and extend the service life.

[0041] Preferably, the connecting rod head 13 is connected to the square hole rocker arm 8 and the clamping block rocker arm 9 through a pin shaft 12, and a sliding bearing is provided at the connection point to reduce the friction coefficient, prevent rotation jamming, and improve the movement performance of the structure. A cotter pin 11 is provided at the tail of the pin shaft 12 to prevent the pin shaft 12 from falling off.

[0042] Preferably, it also includes a locator bracket 3 adapted to the locator 4 and a limit switch bracket 6 adapted to the limit switch 5. Long holes are arranged on the sides between the locator bracket 3 and the limit switch 5. This allows the installation of locators 4 and limit switches 5 of different heights, thereby improving the adaptability of the present structure.

[0043] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A transmission mechanism for valve body linkage, characterized in that: The utility model comprises two connecting rods which are detachably connected to the positioner and the limit switch respectively, and a connecting component which enables the positioner and the limit switch to be flexibly connected is arranged between the two connecting rods.

2. A transmission mechanism for valve body mechanism linkage according to claim 1, characterized in that: The connecting assembly comprises a box body, a buffer spring is arranged in the box body, and the two connecting rods are both slidably arranged in the box body and abut against the buffer spring.

3. A transmission mechanism for valve body mechanism linkage according to claim 2, characterized in that: The box body comprises an upper box body and a lower box body, and the upper box body and the lower box body are detachably connected.

4. A transmission mechanism for valve body mechanism linkage according to claim 2, characterized in that: Both ends of the box body are provided with first sliding bearings which are slidably connected with the connecting rod.

5. The transmission mechanism for valve body linkage according to claim 2, characterized in that: A top plate is provided at one end of the connecting rod abutting against the buffer spring.

6. A transmission mechanism for valve body mechanism linkage according to any one of claims 1 to 5, characterized in that: It also includes two connecting rod heads which are detachably connected to the two connecting rods respectively, and the connecting rod heads are provided with locking nuts which are threadedly connected to the connecting rods. A first fixing component is provided between one of the connecting rod heads and the positioner; and a second fixing component is provided between the other connecting rod head and the limit switch.

7. A transmission mechanism for valve body mechanism linkage according to claim 6, characterized in that: The first fixing component includes a square hole rocker arm rotatably connected to the connecting rod head, the output end of the positioner is inserted into the square hole of the square hole rocker arm, and a mounting hole is opened on the outer side wall of the square hole rocker arm. A screw threadedly connected to the output end of the positioner is provided in the mounting hole.

8. The transmission mechanism for valve body linkage according to claim 6, characterized in that: The second fixing assembly includes a clamping block rocker arm, a feedback rod and a fastener connected to the connecting rod head pin, the feedback rod is inserted in the clamping area of ​​the clamping block rocker arm and fixed by a fastener, a bearing seat is provided on the feedback rod, a second sliding bearing is provided between the bearing seat and the feedback rod, the bearing seat is fixed on the bracket of the limit switch, and the feedback rod is transmission connected to the input end of the limit switch.

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