Variable aperture adjusting device for new energy charging port cover

By designing a variable aperture adjustment device, the combination of threaded adjustment rod and guide support block is used to solve the problem that the traditional charging port cover cannot be applied to different apertures, and the versatile installation of the charging port cover is achieved.

CN120422945APending Publication Date: 2025-08-05YANCHENG GUANGSHUO PRECISION ELECTRONICS CO LTD
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Patent Information

Application Number
CN202510748789.7
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2025-06-06
Publication Date
2025-08-05

AI Technical Summary

Technical Problem

Due to the fixed structure of the traditional new energy charging port cover, it cannot be effectively applied to charging interfaces with different aperture structures, resulting in reduced installation versatility and practicality.

Method used

A new energy charging port cover variable aperture adjustment device is designed. Through the combination of a threaded adjustment rod, a guide support block and a return spring, the charging port cover device clamps and installs the inner support of charging sockets of different sizes and sizes. The adjustment bolts and threaded adjustment rods drive the synchronous movement of the guide support block and the slider to ensure that the inner support bar can fit into the inner wall of the charging socket.

Benefits of technology

The installation versatility of the charging port cover to the charging socket is improved, and the fixed plug structure of the traditional charging port cover is abandoned, so as to realize the suitability of the sockets of different apertures.

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Abstract

The invention provides a new energy charging port cover variable aperture adjusting device, and relates to the technical field of new energy charging, and the new energy charging port cover variable aperture adjusting device comprises a threaded adjusting rod, an adjusting bolt, a guide supporting block and a return spring; a rotary button is installed on the upper side face of the threaded adjusting rod, and a supporting sleeve is rotationally connected to the outer side face of the threaded adjusting rod. The inner side face of the supporting sleeve is slidably connected with a pressing plate, and the outer side face of the supporting sleeve is screwed with a cover seat. The guide supporting block is welded with the return spring; a sliding plate is welded on the lower side surface of the guide supporting block; the outer side face of the adjusting bolt is in meshed connection with a sliding block, and an inner supporting rod is welded to the bottom end of the sliding block. By arranging an adjusting bolt, a sliding block, a threaded adjusting rod and a pressing plate, the charging port cover can be used for internally supporting, clamping and installing charging sockets with different apertures, and the charging port cover can be used for installing the charging sockets more universally; the problem that a traditional new energy charging port cover cannot be effectively suitable for being installed on charging interfaces of different aperture structures due to the fact that the structure of the traditional new energy charging port cover is fixed is solved.
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Description

Technical Field

[0001] The present invention belongs to the field of new energy charging technology, and more specifically, relates to a variable aperture adjustment device for a new energy charging port cover. Background Art

[0002] The new energy charging port cover is a cover installed on the charging structure of new energy vehicles. It is mainly used to cover and protect the charging interface, preventing external dust, air moisture and other pollutants from entering the inside of the charging interface, thereby ensuring the normal use of the charging interface and the structural safety of the connector. At present, new energy charging ports are usually divided into DC fast charging interfaces and AC slow charging interfaces. Due to the differences in the interface structure design of automobile manufacturers and the different number of internal terminal placement of fast charging interfaces and slow charging interfaces, the diameters of the circular socket slots of the charging ports are different. Therefore, the charging ports of new energy vehicles produced by different manufacturers need to be prefabricated with charging port covers of corresponding aperture sizes for adaptive plug-in installation. It can be seen that the plug-in closure structure of the traditional new energy vehicle charging port cover is rigidly fixed, and the new energy charging port cover cannot be adapted for plug-in installation according to the circular socket aperture of different automobile manufacturers, which reduces the practicality and installation versatility of the new energy charging port cover. Summary of the Invention

[0003] In order to solve the above technical problems, the present invention provides a variable aperture adjustment device for a new energy charging port cover to solve the problem that the traditional new energy charging port cover cannot be effectively installed on charging interfaces with different aperture structures due to its fixed structure.

[0004] The present invention provides a device for adjusting the variable aperture of a new energy charging port cover, comprising a charging port mounting panel; a through hole is provided on the upper side of the charging port mounting panel, a charging socket is mounted in the through hole of the charging port mounting panel, and a connecting belt is rotatably connected to the upper side of the charging port mounting panel; the device also comprises a charging port cover plug-in device; the charging port cover plug-in device comprises a support sleeve, a threaded adjustment rod and a pressure plate; the inner side of the support sleeve is slidably connected to the pressure plate, the upper side of the support sleeve is connected to the top cover by bolts, the outer side of the support sleeve is screwed to the cover seat, and the lower side of the cover seat is bonded to an annular rubber gasket, the upper end of the threaded adjustment rod is equipped with a rotary knob, the bottom end is welded with a limit plate, and the threaded adjustment rod passes through the support sleeve and is threadedly connected to the pressure plate; A plurality of guide support blocks are provided around the limit plate, a return spring is provided between the side of the guide support block away from the limit plate and the support sleeve, a slide is welded on the lower side of the guide support block, a support frame is provided on the lower side of the slide, a clamping bolt is provided between the slide and the support frame, a slider is provided on the support frame which is radially slidable along the support sleeve, an adjusting bolt which is threadedly connected to the slider is rotatably connected to the support frame, an inner support rod is welded on the bottom end of the slider, and a rubber sleeve is bonded to the outer side of the inner support rod.

[0005] In at least some embodiments, the number of the guide support blocks is four groups, and the guide support blocks are distributed in a circular array around the central axis of the support sleeve. The left and right sides of each group of guide support blocks are provided with long convex strips, and the upper end of the guide support block is a slope.

[0006] In at least some embodiments, the support sleeve is a disc-shaped structure, and a through hole is provided at the center of the disc-shaped structure of the support sleeve, which passes through the vertical direction. The inner wall of the central through hole of the support sleeve is provided with two groups of small sliding grooves that pass through the vertical direction. The inner wall of the central through hole of the support sleeve is provided with four groups of open grooves that pass through the vertical direction. The opening grooves of the support sleeve are distributed in a circular array around the vertical center axis of the support sleeve, and the groove wall of each group of opening grooves is provided with a long groove, and the convex strips of the guide support block are embedded in the long grooves of the groove wall of the opening groove of the support sleeve.

[0007] In at least some embodiments, the pressure plate is a disc-shaped structure, and two groups of protrusions are provided on the outer side of the pressure plate. The protrusions of the pressure plate are embedded in the small slide groove of the support sleeve. A threaded through hole is provided at the center position of the upper side of the pressure plate, and the outer side of the threaded adjustment rod is threadedly engaged with the threaded through hole of the pressure plate.

[0008] In at least some embodiments, the number of the return springs is four groups, one end of the return spring is welded with a guide support block, and the other end of the return spring is welded to the bottom of the opening groove of the support sleeve.

[0009] In at least some embodiments, the number of the sliders is four groups, each group of sliders is provided with a threaded through hole, the outer side of the adjusting bolt is threadedly engaged in the threaded through hole of the slider, and the upper side of the slider is attached to the lower side of the support frame.

[0010] In at least some embodiments, the number of the support frames is four groups, and each group of support frames is provided with a fan-shaped protrusion on the upper side, and a threaded hole is provided at the center position of the upper side of the fan-shaped protrusion of the support frame, and a clamping bolt is screwed into the threaded hole of the support frame.

[0011] In at least some embodiments, the number of the skateboards is four groups, each group of skateboards is a fan-shaped structure, and the four groups of skateboards are distributed in a circular array around the vertical center axis of the limit plate. The lower side of the skateboard is provided with an arc-shaped groove, and the bottom of the arc-shaped groove is provided with an arc-shaped through groove that passes through the upper and lower parts. The fan-shaped protrusion on the upper side of the support frame is embedded in the arc-shaped groove of the skateboard, and the clamping bolts are inserted into the arc-shaped through groove of the skateboard.

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. In the present invention, on the one hand, the threaded engagement transmission structure formed by the adjusting bolt in the threaded through hole of the slider operates, so that the slider drives the inner support rod to move and adjust the insertion position of the inner support rod according to the aperture of the charging socket. On the other hand, the threaded adjustment rod is used to drive the pressure plate to push the inclined structure of the four groups of guide support blocks, so that the guide support blocks drive the four groups of inner support rods to move synchronously centrifugally through the slide plate and the support frame. The rubber sleeves bonded to the outer sides of the four groups of inner support rods are bonded to the inner wall of the charging socket, thereby realizing the inner support clamping and adaptation installation work of the charging port cover device for charging sockets of different apertures, abandoning the fixed plug-in structure of the traditional charging port cover, and improving the versatility of the charging port cover for charging socket installation. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of the present invention.

[0014] Figure 2 It is a schematic structural diagram of the charging socket in the open state of the present invention.

[0015] Figure 3 It is a structural schematic diagram of the charging port cover device of the present invention.

[0016] Figure 4 It is a schematic diagram of the charging port cover device of the present invention when viewed from above and side.

[0017] Figure 5 It is a bottom view structural diagram of the charging port cover device of the present invention.

[0018] Figure 6 It is a front view structural schematic diagram of the charging port cover device of the present invention.

[0019] Figure 7 It is a schematic diagram of the cross-sectional structure of the charging port cover device of the present invention from top and side views.

[0020] Figure 8 The present invention Figure 7 Schematic diagram of the enlarged structure of part A in the middle.

[0021] Figure 9 It is a schematic diagram of the cross-sectional structure of the charging port cover device of the present invention when viewed from above and side.

[0022] Figure 10 It is a schematic diagram of the exploded structure of the charging port cover device of the present invention.

[0023] Figure 11 The present invention Figure 10 Schematic diagram of the enlarged structure of part B in the middle.

[0024] Reference numerals: 1. Install the charging port panel; 2. Connecting belt; 3. Charging port cover assembly; 301. Knob; 302. Top cover; 303. Support sleeve; 304. Cover seat; 305. Annular rubber gasket; 306. Threaded adjustment rod; 307. Rubber sleeve; 308. Slider; 309. Adjusting bolt; 310. Slide plate; 311. Limiting plate; 312. Support frame; 313. Guide support block; 314. Pressure plate; 315. Return spring; 316. Clamping bolt; 317. Inner support rod; 4. Charging port. DETAILED DESCRIPTION

[0025] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0026] like Figures 1-11 As shown, the present invention provides a new energy charging port cover variable aperture adjustment device, including a charging port mounting panel 1; a through hole is provided on the upper side of the charging port mounting panel 1, a charging socket 4 is installed in the through hole of the charging port mounting panel 1, and a connecting belt 2 is rotatably connected to the upper side of the charging port mounting panel 1; it also includes a charging port cover device 3; the charging port cover device 3 includes a support sleeve 303, a threaded adjustment rod 306 and a pressure plate 314; the inner side of the support sleeve 303 is slidably connected to the pressure plate 314, the upper side of the support sleeve 303 is connected to the top cover 302 by bolts, the outer side of the support sleeve 303 is screwed with the cover seat 304, and the lower side of the cover seat 304 is bonded with an annular rubber gasket 305, the upper end of the threaded adjustment rod 306 is installed with a knob 301, and the bottom end is welded with a limit plate 311, and the threaded adjustment rod 306 passes through the support sleeve 303 and is threadedly connected to the pressure plate 314; A plurality of guide support blocks 313 are circumferentially provided with the limit plate 311, and a return spring 315 is provided between the side of the guide support block 313 away from the limit plate 311 and the support sleeve 303, a slide plate 310 is welded to the lower side of the guide support block 313, a support frame 312 is provided on the lower side of the slide plate 310, a clamping bolt 316 is provided between the slide plate 310 and the support frame 312, a slider 308 is provided on the support frame 312 and is radially slidable along the support sleeve 303, an adjusting bolt 309 is rotatably connected to the support frame 312 and is threadedly connected to the slider 308, an inner support rod 317 is welded to the bottom end of the slider 308, and a rubber sleeve 307 is bonded to the outer side of the inner support rod 317.

[0027] In the embodiment of the present disclosure, there are four groups of guide support blocks 313, which are distributed in a circular array around the central axis of the support sleeve 303. The left and right sides of each group of guide support blocks 313 are provided with long convex strips, the upper side of the guide support block 313 has an inclined structure, and the edge position of the lower side of the pressure plate 314 contacts and squeezes the inclined structure of the guide support block 313, so that the four groups of guide support blocks 313 synchronously drive the slide plate 310 welded to the lower side to move centrifugally, and the four groups of slide plates 310 respectively drive the four groups of inner support rods 317 to move synchronously, so that the inner support rods 317 contact the slot wall of the charging socket 4, completing the inner support clamping and fixed installation of the charging port cover device 3 in the charging socket 4.

[0028] In the embodiment of the present disclosure, the support sleeve 303 is a disc-shaped structure, and a through hole is provided at the center of the disc-shaped structure of the support sleeve 303, and two groups of small sliding grooves are provided on the inner wall of the central through hole of the support sleeve 303, and four groups of open grooves are provided on the inner wall of the central through hole of the support sleeve 303. The opening grooves of the support sleeve 303 are distributed in a circular array around the vertical center axis of the support sleeve 303, and each group of opening grooves is provided with a long groove on the groove wall. The convex strips of the guide support block 313 are embedded in the long grooves of the groove wall of the opening groove of the support sleeve 303. The long grooves of the support sleeve 303 support the four groups of guide support blocks 313 to slide horizontally along the groove wall of the opening groove, ensuring that the four groups of inner support rods 317 stably contact the inner wall of the charging socket 4.

[0029] In the embodiment of the present disclosure, the pressure plate 314 is a disc-shaped structure, and two groups of protrusions are provided on the outer side of the pressure plate 314. The protrusions of the pressure plate 314 are embedded in the small slide groove of the support sleeve 303. A threaded through hole is provided at the center position of the upper side of the pressure plate 314, and the outer side of the threaded adjustment rod 306 is threadedly engaged with the threaded through hole of the pressure plate 314. During the process of the threaded adjustment rod 306 driven by the knob 301 to rotate, the threaded adjustment rod 306 drives the pressure plate 314 to move vertically up and down along the small slide groove of the support sleeve 303, so that the edge of the lower side of the disc-shaped structure of the pressure plate 314 can simultaneously contact and squeeze the four groups of guide support blocks 313, allowing the four groups of guide support blocks 313 to perform synchronous centrifugal motion.

[0030] In the disclosed embodiment, there are four groups of return springs 315. A guide support block 313 is welded to one end of the return spring 315, and the other end of the return spring 315 is welded to the bottom of the opening groove of the support sleeve 303. During the upward movement of the pressure plate 314, the return spring 315 drives the guide support block 313 to move synchronously and centripetally through its own elastic force, so that the inner support rod 317 automatically detaches from the inner wall of the charging socket 4 for loosening and pulling out.

[0031] In the embodiment of the present disclosure, there are four groups of sliders 308, and each group of sliders 308 is provided with a threaded through hole. The outer side surface of the adjusting bolt 309 is threadedly engaged with the threaded through hole of the slider 308, and the upper side surface of the slider 308 is attached to the lower side surface of the support frame 312. During the rotation of the four groups of adjusting bolts 309, the four groups of sliders 308 are driven to move horizontally centripetally or horizontally centrifugally along the lower side surface of the support frame 312. The distance between the slider 308 and the vertical center axis of the support sleeve 303 is changed according to the aperture size of the charging socket 4, so that the charging port cover device 3 can adapt to charging sockets 4 with different aperture sizes.

[0032] In the embodiment of the present disclosure, there are four groups of support frames 312, and each group of support frames 312 is provided with a fan-shaped protrusion on the upper side. A threaded hole is provided at the center position of the upper side of the fan-shaped protrusion of the support frame 312, and a clamping bolt 316 is screwed into the threaded hole of the support frame 312. The nut of the clamping bolt 316 cooperates with the upper side of the fan-shaped protrusion of the support frame 312 to clamp the skateboard 310 up and down, so that the support frame 312 can be clamped and fixed at any position of the arc groove of the skateboard 310.

[0033] In the embodiment of the present disclosure, there are four groups of skateboards 310, and each group of skateboards 310 is a fan-shaped structure. The four groups of skateboards 310 are distributed in a circular array around the vertical center axis of the limit plate 311. The lower side of the skateboard 310 is provided with an arc-shaped groove, and the bottom of the arc-shaped groove is provided with an upper and lower through-arc-shaped groove. The fan-shaped protrusion on the upper side of the support frame 312 is embedded in the arc-shaped groove of the skateboard 310, and the clamping bolt 316 is inserted into the arc-shaped groove of the skateboard 310. The support frame 312 rotates and moves along the arc-shaped groove of the skateboard 310 around the vertical center axis of the limit plate 311 through the fan-shaped protrusion, so that the support frame 312 drives the inner support rod 317 to adjust the insertion position of the inner support rod 317 into the charging socket 4 according to the different internal structures of the charging socket 4.

[0034] The specific usage and function of this embodiment are as follows: When the charging port cover device 3 is adjusted and installed to suit the charging socket 4, a screwdriver is first used to rotate the four sets of adjustment bolts 309. Since the outer side of the adjustment bolts 309 is threadedly engaged with the threaded through hole of the slider 308, the four sets of adjustment bolts 309 respectively drive the slider 308 to move horizontally centripetally or horizontally centrifugally in accordance with the lower side of the support frame 312, so that the slider 308 drives the inner support rod 317 to move synchronously. The insertion position of the inner support rod 317 in the charging socket 4 is changed according to the aperture size of the charging socket 4, and then the annular rubber bonded to the lower side of the cover seat 304 is adjusted. The gasket 305 covers and fits on the upper side of the charging port mounting panel 1, and then the knob 301 is manually turned, and the knob 301 drives the threaded adjustment rod 306 to rotate. Since the outer side of the threaded adjustment rod 306 is threadedly engaged with the threaded through hole of the pressure plate 314, the threaded adjustment rod 306 drives the pressure plate 314 to move downward along the small slide groove of the support sleeve 303. The edge position of the lower side of the pressure plate 314 pushes the inclined structure of the four groups of guide support blocks 313. The guide support blocks 313 slide along the long groove on the inner wall of the opening groove of the support sleeve 303, and the guide support blocks 313 drive the slide plate 3 welded on the lower side. 10 slide synchronously, the four sets of slides 310 respectively drive the four sets of support frames 312 to move horizontally centrifugally, and the four sets of support frames 312 respectively drive the four sets of inner support rods 317 welded to the lower side of the sliders 308 to move synchronously centrifugally until the rubber sleeve 307 bonded to the outer side of the inner support rod 317 is tightly fitted in contact with the inner side wall of the charging socket 4, and the inner support clamping installation work of the charging port cover device 3 at the charging socket 4 is completed. If the charging port cover device 3 needs to be removed from the charging socket 4, the knob 301 is rotated in the opposite direction, and the knob 301 drives the threaded adjustment rod 306 to rotate in the opposite direction. The threaded adjustment rod 306 drives the pressure plate 314 to move upward along the small slide groove of the support sleeve 303, and the edge of the lower side of the pressure plate 314 detaches from the inclined structure of the four groups of guide support blocks 313. At this time, the four groups of return springs 315 push the four groups of guide support blocks 313 to slide centripetally along the long groove on the inner wall of the opening groove of the support sleeve 303. At this time, the inner support rod 317 moves synchronously with the guide support block 313, and the rubber sleeve 307 bonded to the outer side of the inner support rod 317 detaches from the inner wall of the charging socket 4, and then pulls the charging port cover device 3 upward, thereby completing the removal of the charging port cover device 3 at the charging socket 4.

[0035] All of the above components are installed, connected, or configured using common mechanical methods, such as welding, threaded connections, and screw connections. The specific structures, models, and coefficients of all components are proprietary technologies and can be implemented as long as they can achieve the desired effect. The annular rubber gasket 305 and charging socket 4 are both commonly available components. Upon purchase, they can be connected and used according to the included instruction manual, so further details will not be provided here.

[0036] The technical solutions of the present invention are not limited to the scope of the embodiments of the present invention, and the technical contents not described in detail in the present invention are all well-known technologies.

Claims

1. A new energy charging port cover variable aperture adjustment device, comprising a charging port mounting panel (1); a through hole is provided on the upper side of the charging port mounting panel (1), a charging socket (4) is installed in the through hole of the charging port mounting panel (1), and a connecting belt (2) is rotatably connected to the upper side of the charging port mounting panel (1); the characteristics are: The charging port cover device (3) is also included; the charging port cover device (3) includes a support sleeve (303), a threaded adjustment rod (306) and a pressure plate (314); the inner side of the support sleeve (303) is slidably connected to the pressure plate (314), the upper side of the support sleeve (303) is connected to the top cover (302) by bolts, the outer side of the support sleeve (303) is screwed to the cover seat (304), and the lower side of the cover seat (304) is bonded with an annular rubber gasket (305), the upper end of the threaded adjustment rod (306) is installed with a knob (301), and the bottom end is welded with a limit plate (311), and the threaded adjustment rod (306) passes through the support sleeve (303) and is threadedly connected to the pressure plate (314); The limiting plate (311) is provided with a plurality of guide support blocks (313) in the circumferential direction. A return spring (315) is provided between the side of the guiding support block (313) away from the limiting plate (311) and the support sleeve (303). A slide plate (310) is welded to the lower side of the guiding support block (313). A support frame (312) is provided on the lower side of the slide plate (310). A clamping bolt (316) is provided between the slide plate (310) and the support frame (312). A slider (308) is provided on the support frame (312) and is radially slidable along the support sleeve (303). An adjusting bolt (309) is rotatably connected to the support frame (312) and is threadedly connected to the slider (308). An inner support rod (317) is welded to the bottom end of the slider (308), and a rubber sleeve (307) is bonded to the outer side of the inner support rod (317).

2. A new energy charging port cover variable aperture adjustment device as claimed in claim 1, characterized in that: The number of the guide support blocks (313) is four groups, and the guide support blocks (313) are distributed in a circular array around the central axis of the support sleeve (303). The left and right sides of each group of guide support blocks (313) are provided with long convex strips, and the upper end of the guide support block (313) is an inclined surface.

3. The variable aperture adjustment device for a new energy charging port cover according to claim 2, characterized in that: The support sleeve (303) is a disc-shaped structure. A through hole extending vertically is provided at the center of the disc-shaped structure of the support sleeve (303). Two groups of small sliding grooves extending vertically are provided on the inner side wall of the central through hole of the support sleeve (303). Four groups of opening grooves extending vertically are provided on the inner side wall of the central through hole of the support sleeve (303). The opening grooves of the support sleeve (303) are distributed in a circular array around the vertical center axis of the support sleeve (303). A long groove is provided on the groove wall of each group of opening grooves. The convex strips of the guide support block (313) are embedded in the long grooves of the groove wall of the opening groove of the support sleeve (303).

4. The variable aperture adjustment device for a new energy charging port cover according to claim 1, characterized in that: The pressing plate (314) is a disc-shaped structure. Two groups of protrusions are provided on the outer side of the pressing plate (314). The protrusions of the pressing plate (314) are embedded in the small chute of the support sleeve (303). A threaded through hole is provided at the center of the pressing plate (314) and is threadedly engaged with the outer side of the threaded adjustment rod (306) in the threaded through hole of the pressing plate (314).

5. The variable aperture adjustment device for a new energy charging port cover according to claim 1, characterized in that: The number of the return springs (315) is four groups. One end of the return spring (315) is welded to a guide support block (313), and the other end of the return spring (315) is welded to the bottom of the opening groove of the support sleeve (303).

6. The variable aperture adjustment device for a new energy charging port cover according to claim 1, characterized in that: The number of the sliders (308) is four groups, and each group of sliders (308) is provided with a threaded through hole. The outer side surface of the adjusting bolt (309) is threadedly engaged with the threaded through hole of the slider (308), and the upper side surface of the slider (308) is attached to the lower side surface of the support frame (312).

7. The variable aperture adjustment device for a new energy charging port cover according to claim 1, characterized in that: The number of the support frames (312) is four groups, and a fan-shaped protrusion is provided on the upper side of each group of support frames (312). A threaded hole is provided at the center position of the upper side of the fan-shaped protrusion of the support frame (312), and a clamping bolt (316) is screwed into the threaded hole of the support frame (312).

8. The variable aperture adjustment device for a new energy charging port cover according to claim 1, characterized in that: The number of the slides (310) is four groups, and each group of slides (310) is a fan-shaped structure. The four groups of slides (310) are distributed in a circular array around the vertical center axis of the limit plate (311). The lower side of the slide (310) is provided with an arc-shaped groove, and the bottom of the arc-shaped groove is provided with an upper and lower through-arc-shaped groove. The fan-shaped protrusion on the upper side of the support frame (312) is embedded in the arc-shaped groove of the slide (310), and the clamping bolt (316) is inserted into the arc-shaped groove of the slide (310).