Sucking disc

Abstract

The utility model discloses a suction cup which is good in sealing effect, firm in adsorption and long in service life and comprises a suction cup seat, a support is arranged on the suction cup seat in a penetrating mode, and a suction cup frame is arranged at the lower end of the support. A matching hole is formed in the bottom of the suction disc, the suction disc frame is arranged in the matching hole to support the suction disc, and the support upwards penetrates out of the suction disc and is connected with the control mechanism on the suction disc seat; the control mechanism controls the support and the suction cup frame to ascend, the linkage suction cup ascends, the edge of the suction cup abuts against the blocking part, the center position of the suction cup deforms upwards and is folded, and the inner wall of the matching hole is tightly attached to the suction cup frame to form sealing. The control mechanism controls the support and the sucker frame to descend, the adsorption disc is linked to descend, the center position of the adsorption disc deforms downwards and is unfolded, and a gap is formed between the inner wall of the matching hole and the sucker frame. The utility model relates to the technical field of suckers.

Description

Technical Field

[0001] The utility model relates to the technical field of suction cups, and more specifically to a suction cup. Background Art

[0002] In daily life, suction cups are often used to connect substrates and objects, where the substrate can be a flat surface such as a desktop or a mirror.

[0003] A suction cup is a connector that uses the difference in atmospheric pressure between inside and outside to adhere to a smooth object. It is usually used as a pendant or to fix an object.

[0004] The existing suction cup is usually an integral structure (i.e., the suction cup frame and the suction cup are fixedly connected, or the structure is designed as an integrated structure). When the suction cup and the substrate are released from adsorption, the deformation of the suction cup is restored by the operating mechanism.

[0005] Eliminate the vacuum space created by the deformation of the suction plate during adsorption. However, after the suction plate ages, the vacuum space cannot be completely eliminated when the adsorption is released, but can only be reduced, making it difficult to remove the suction cup.

[0006] The adsorption between the adsorption plate and the substrate cannot be released quickly and effectively, and needs to be operated through the operating mechanism multiple times, which is not conducive to one-handed operation;

[0007] In addition, the adsorption disk made of soft material is prone to aging and hardening during long-term use, and the adsorption disk is not easy to deform, resulting in poor sealing effect with the pull plate, and the service life cannot meet the requirements. Utility Model Content

[0008] In view of the shortcomings and defects of the prior art, a suction cup is provided which has good sealing effect, firm adsorption, long service life and can quickly release adsorption of the adsorption cup.

[0009] A suction cup, comprising:

[0010] A suction cup seat, wherein a bracket is provided on the suction cup seat, and a suction cup frame is provided at the lower end of the bracket;

[0011] An elastic adsorption plate, wherein a matching hole is provided at the bottom of the adsorption plate, and the adsorption plate frame is installed into the matching hole to support the adsorption plate, and the bracket passes through the adsorption plate upward and is connected to the operating mechanism on the adsorption plate seat;

[0012] The operating mechanism operates the bracket and the suction cup frame to rise, and the suction cup is linked to rise, the edge of the suction cup abuts against the blocking part, the center of the suction cup is deformed upward and folded, the inner wall of the matching hole is tightly attached to the suction cup frame to form a seal, and the suction cup is adsorbed on the substrate;

[0013] The operating mechanism operates the bracket and the suction cup frame to descend, and a gap is formed between the suction cup frame and the inner wall of the matching hole to allow air to enter between the adsorption plate and the substrate;

[0014] An elastic member, one end of which is stopped, and the other end is abutted against the upper end of the adsorption plate. When the adsorption plate rises, the elastic member is pre-tightened and pressed against the adsorption plate, so that the adsorption plate is in close contact with the suction cup frame.

[0015] After adopting the above structure, the suction cup of the utility model has the following advantages compared with the prior art: after the above improvement, the suction cup and the suction cup frame are separately arranged, and when the suction cup frame descends, a gap is formed between the suction cup frame and the inner wall of the matching hole for air to enter, and the center position of the suction cup is deformed downward and unfolded to break away from the adsorption with the substrate. Since there is no adsorption connection between the suction cup frame and the matching hole and the substrate, the gap exists for a long time, and air can continuously enter the area between the suction cup and the substrate, so that the adsorption of the substrate by the suction cup can be quickly and effectively released;

[0016] When the suction cup frame is linked with the adsorption plate to rise, the spring is pre-tightened, and a downward pre-tightening force is applied to the adsorption plate, driving the adsorption plate and the suction cup frame to be in closer contact, thereby improving the sealing effect between the inner wall of the matching hole and the suction cup frame, and the adsorption plate is more firmly adsorbed to the substrate;

[0017] In addition, the suction cup made of soft material will easily become hard and have poor flexibility after long-term use. During adsorption, the suction cup is not easy to deform, and a gap is easily formed between the suction cup frame, resulting in poor sealing effect. After using the spring, the suction cup is pressed against the suction cup frame after pre-tightening the spring, which can obtain a better sealing effect and increase the service life of the device.

[0018] As an improvement of the utility model, the elastic member is a coil spring, which is sleeved on the outside of the bracket, and the upper end of the coil spring abuts against the suction cup seat, and the lower end of the coil spring abuts against the adsorption plate.

[0019] As an improvement of the present invention, the suction cup frame is integrally formed with the bracket, and the suction cup frame is extended radially outwardly along the bracket.

[0020] As an improvement of the present invention, the inner diameter of the matching hole and the outer diameter of the suction cup frame are both gradually increased from top to bottom, and the inner diameter of the matching hole is larger than the outer diameter of the suction cup frame.

[0021] As an improvement of the utility model, a first annular flange is provided on the upper end surface of the suction cup frame near the edge, and a second annular flange is provided on the upper end surface of the suction cup frame inside the first annular flange, a first fitting groove is formed between the first annular flange and the second annular flange, and a second fitting groove is formed between the second annular flange and the bracket;

[0022] A first annular fitting block and a second annular fitting block are provided at the bottom of the matching hole. The first annular fitting block is loosely matched with the first fitting groove, and the second annular fitting block is loosely matched with the second fitting groove.

[0023] As an improvement of the present invention, the bottom of the second mating groove, the top of the first annular flange and the top of the second annular flange are respectively provided with recesses along the same radial direction, a gap is formed between the recess and the surface of the suction cup at the bottom of the matching hole, and the gap between the inner circumferential wall of the matching hole and the outer circumferential wall of the suction cup frame is connected to the recess on the second annular flange.

[0024] As an improvement of the present utility model, the bottom of the second engaging groove is provided with a pin body protruding upward, and the second annular engaging block is provided with a connecting hole for the pin body to penetrate.

[0025] As an improvement of the present invention, the cross sections of the first annular fitting block and the second annular fitting block are both configured to be wide at the top and narrow at the bottom.

[0026] As an improvement of the present invention, the adsorption plate is provided with an assembly space, the elastic member, the suction cup frame and the adsorption plate are arranged in the assembly space, and the annular flange arranged at the edge position of the bottom opening of the assembly space is the blocking part.

[0027] As an improvement of the utility model, the operating mechanism comprises:

[0028] A rotating frame, wherein the rotating frame is rotatably arranged on the suction cup seat, the upper end of the bracket passes through the inner side of the rotating frame, the upper end of the bracket is provided with a transmission pin, the rotating frame is provided with an inclined driving surface with a height gradually decreasing from high to low, the transmission pin is in contact with the driving surface, and the driving surface is coaxially arranged with the rotating frame;

[0029] Rotate the rotating frame to switch to a higher driving surface to contact the transmission pin, so as to drive the bracket to rise;

[0030] The rotating frame is rotated to switch to a driving surface with a lower height to cooperate with the transmission pin to drive the bracket to descend. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a structural schematic diagram of the utility model.

[0032] Figure 2 It is a schematic diagram of the structure of the utility model after the handle and the rotating frame are separated.

[0033] Figure 3 It is a schematic diagram of the structure of the parts of the utility model in the exploded state.

[0034] Figure 4It is a structural schematic diagram of the bracket and the suction cup frame of the utility model.

[0035] Figure 5 It is a cross-sectional schematic diagram of the adsorption disk of the utility model after the adsorption is released.

[0036] Figure 6 It is a cross-sectional schematic diagram of the adsorption disk of the utility model during adsorption.

[0037] As shown in the figure: 1. Suction cup seat; 1.1. Blocking part; 1.2. Assembly space; 2. Bracket; 2.1. Suction cup frame; 3. Adsorption disc; 3.1. Matching hole; 3.2. First annular fitting block; 3.3. Second annular fitting block; 4. Operating mechanism; 4.1. Rotating frame; 4.11. Driving surface; 4.111. Positioning groove; 4.2. Transmission pin; 5. Elastic member; 6. First annular flange; 7. Second annular flange; 8. First fitting groove; 9. Second fitting groove; 9.1. Pin body; 10. Notch; 11. Handle. DETAILED DESCRIPTION

[0038] The utility model is further described below in conjunction with the accompanying drawings and specific embodiments.

[0039] See also Figure 1-6 As shown, a suction cup comprises:

[0040] A suction cup seat 1, a bracket 2 is provided on the suction cup seat 1, and a suction cup frame 2.1 is provided at the lower end of the bracket 2;

[0041] An elastic adsorption plate 3, wherein a matching hole 3.1 is provided at the bottom of the adsorption plate 3, and the adsorption plate frame 2.1 is inserted into the matching hole 3.1 to support the adsorption plate 3, and the bracket 2 passes through the adsorption plate 3 upward and is connected to the operating mechanism 4 on the adsorption plate seat 1;

[0042] The operating mechanism 4 operates the bracket 2 and the suction cup frame 2.1 to rise, and the suction cup 3 is linked to rise, the edge of the suction cup 3 abuts against the blocking part 1.1, the center of the suction cup 3 is deformed upward and folded, the inner wall of the matching hole 3.1 is tightly attached to the suction cup frame 2.1 to form a seal, and the suction cup 3 is adsorbed on the substrate;

[0043] The operating mechanism 4 operates the bracket 2 and the suction cup frame 2.1 to descend, and a gap is formed between the suction cup frame 2.1 and the inner wall of the matching hole 3.1 for air to enter between the adsorption plate 3 and the substrate to release the adsorption;

[0044] The elastic member 5 has one end that is stopped and the other end that is pressed against the upper end of the adsorption plate 3. When the adsorption plate 3 rises, the elastic member 5 is pre-tightened and pressed against the adsorption plate 3, so that the adsorption plate 3 is in close contact with the suction cup frame 2.1.

[0045] After adopting the above structure, a suction cup of the utility model has the following advantages compared with the prior art: after the above improvement, the suction cup 3 and the suction cup frame 2.1 are separately arranged, and when the suction cup frame 2.1 descends, a gap is formed between the suction cup frame 2.1 and the inner wall 3.1 of the matching hole for air to enter, and the center position of the suction cup 3 loses the supporting effect of the suction cup frame 2.1 and deforms downward and unfolds to break away from the adsorption with the substrate. Since there is no adsorption connection between the suction cup frame 2.1 and the matching hole 3.1 and the substrate, the gap exists for a long time, and air can continuously enter the area between the suction cup 3 and the substrate, which can quickly and effectively release the adsorption of the suction cup 3 on the substrate.

[0046] When the suction cup frame 2.1 is linked with the suction cup 3 to rise, the spring is pre-tightened, and a downward pre-tightening force is applied to the suction cup 3, driving the suction cup 3 and the suction cup frame 2.1 to be in closer contact, thereby improving the sealing effect between the inner wall of the matching hole 3.1 and the suction cup frame 2.1, and the suction cup 3 and the substrate are more firmly adsorbed;

[0047] In addition, when the adsorption plate 3 made of soft material is used for a long time, the adsorption plate 3 is easy to harden and has poor flexibility. When adsorption is performed, the adsorption plate 3 is not easy to deform, and a gap is easily formed between the adsorption plate 3 and the suction cup frame 2.1, resulting in poor sealing effect. After using the spring, the adsorption plate 3 is pressed against the suction cup frame 2.1 after pre-tightening the spring, which can obtain a better sealing effect and improve the service life of the device.

[0048] As an improvement of the present invention, the elastic member 5 is a coil spring, which is sleeved on the outside of the bracket 2, and the upper end of the coil spring abuts against the suction cup seat 1, and the lower end abuts against the suction cup 3. The use of the coil spring as the elastic member 5 has the characteristics of simple and compact structure, stable and reliable operation, and long service life;

[0049] The lower end of the spring is preferably stopped at the upper end surface of the suction cup 3 at the upper end of the suction cup frame 2.1. The position of the suction cup frame 2.1 is opposite to the bottom end of the coil spring, which can more efficiently and tightly press the suction cup 3 and the suction cup frame 2.1.

[0050] As an improvement of the present invention, the suction cup frame 2.1 is integrally formed with the bracket 2, and the suction cup frame 2.1 is radially extended outwardly along the bracket 2. After the above improvement, it is convenient for production and processing. In addition, a larger suction cup frame 2.1 is selected, which has a better support for the suction plate 3 and a stable connection with the suction plate 3.

[0051] As an improvement of the present invention, the inner diameter of the matching hole 3.1 and the outer diameter of the suction cup frame 2.1 are both gradually increasing from top to bottom, and the inner diameter of the matching hole 3.1 is larger than the outer diameter of the suction cup frame 2.1. After the above improvement, the circumference of the matching hole 3.1 and the suction cup frame 2.1 are both gradually expanding from top to bottom. When the bracket 2 and the suction cup frame 2.1 move upward, the middle position of the adsorption plate 3 is driven to deform upward and gather inward. The inclined circumference of the matching hole 3.1 can fit the circumference of the suction cup frame 2.1 more quickly and tightly, and the sealing effect of the sealed cavity formed between the bottom of the adsorption plate 3 and the substrate is better, and the adsorption plate 3 firmly adsorbs the substrate.

[0052] Of course, when the bracket 2 and the suction cup frame 2.1 move downward, the middle position of the suction cup 3 is deformed downward and expanded to the outside, and the peripheral surface of the matching hole 3.1 and the peripheral surface of the suction cup frame 2.1 are effectively separated, which can quickly release the adsorption of the substrate by the suction cup 3.

[0053] As an improvement of the present utility model, a first annular flange 6 is provided on the upper end surface of the suction cup frame 2.1 near the edge, and a second annular flange 7 is provided on the upper end surface of the suction cup frame 2.1 inside the first annular flange 6, a first fitting groove 8 is formed between the first annular flange 6 and the second annular flange 7, and a second fitting groove 9 is formed between the second annular flange 7 and the bracket 2;

[0054] The bottom of the matching hole 3.1 is provided with a first annular fitting block 3.2 and a second annular fitting block 3.3, the first annular fitting block 3.2 is loosely fitted with the first fitting groove 8, and the second annular fitting block 3.3 is loosely fitted with the second fitting groove 9. After the above improvement, the bottom of the matching hole 3.1 and the upper end face of the suction cup frame 2.1 are matched through a plurality of fitting blocks and fitting grooves of keyway structure, and during adsorption, the bottom of the matching hole 3.1 and the upper end face of the suction cup frame 2.1 are in better close contact, and the sealing effect is better.

[0055] As an improvement of the present invention, the bottom of the second fitting groove 9, the top of the first annular flange 6 and the top of the second annular flange 7 are respectively provided with notches 10 along the same radial direction, a gap is formed between the notch 10 and the surface of the adsorption disk 3 at the bottom of the matching hole 3.1, and the gap between the inner peripheral wall of the matching hole 3.1 and the outer peripheral wall of the suction cup frame 2.1 is connected to the notch 10 on the second annular flange 7. A gap for air to enter is pre-set between the peripheral side of the bracket 2 and the adsorption disk 3. When it is necessary to release the adsorption of the adsorption disk 3 on the substrate, the air can quickly enter the gap between the peripheral surface of the matching hole 3.1 and the peripheral surface of the adsorption disk 3 from the notch 10, and then enter the cavity between the bottom of the adsorption disk 3 and the substrate, which can effectively release the adsorption of the adsorption disk 3 on the substrate.

[0056] As an improvement of the present invention, the bottom of the second engagement groove 9 is provided with a pin body 9.1 protruding upward, and the second annular engagement block 3.3 is provided with a connection hole for the pin body 9.1 to pass through. After the above improvement, after the pin body 9.1 is connected with the connection hole, it can limit the rotation of the suction plate 3, so that the connection between the suction plate 3 and the suction cup frame 2.1 is more stable.

[0057] As an improvement of the present invention, the cross-sections of the first annular fitting block 3.2 and the second annular fitting block 3.3 are both wide at the top and narrow at the bottom. After the above improvement, the peripheral surfaces of the first annular fitting block 3.2 and the second annular fitting block 3.3, the first fitting groove 8 and the second fitting groove 9 also form an inclined surface that gradually expands outward from top to bottom. The inclined surface is similar to the inclined peripheral surface of the suction cup frame 2.1 and the matching hole 3.1. When the suction cup 3 is deformed upward and folded, the combination of the inclined surfaces can improve the sealing effect.

[0058] As an improvement of the present invention, the suction plate 3 is provided with an assembly space 1.2, the elastic member 5, the suction plate frame 2.1 and the suction plate 3 are arranged in the assembly space 1.2, and the annular flange arranged at the edge of the bottom opening of the assembly space 1.2 is the blocking portion 1.1. After the above improvement, the structure layout is reasonable and compact, and the device occupies a small space; wherein the elastic member 5 is a coil spring.

[0059] As an improvement of the present utility model, the operating mechanism 4 comprises:

[0060] A rotating frame 4.1, the rotating frame 4.1 is rotatably arranged on the suction cup seat 1, the upper end of the bracket 2 passes through the inner side of the rotating frame 4.1, the upper end of the bracket 2 is provided with a driving pin 4.2, the rotating frame 4.1 is provided with an inclined driving surface 4.11 with a height gradually decreasing from high to low, the driving pin 4.2 is in contact with the driving surface 4.11, and the driving surface 4.11 is coaxially arranged with the rotating frame 4.1;

[0061] Rotate the rotating frame 4.1 to switch to a higher driving surface 4.11 in contact with the driving pin 4.2 to drive the bracket 2 to rise;

[0062] The rotating frame 4.1 is rotated to switch to a driving surface 4.11 with a lower height to cooperate with the driving pin 4.2 to drive the bracket 2 to descend.

[0063] When the transmission pin 4.2 is at a lower height of the driving surface 4.11, the bracket 2 moves downward to the limit position. At this time, the adsorption plate 3 is flatly unfolded and is in an unlocked state, that is, the adsorption plate 3 is detached from the base;

[0064] At this time, if the rotating frame 4.1 is rotated, the driving surface 4.11 contacted by the transmission pin 4.2 gradually changes from the lower side to the higher side, the bracket 2 is driven to gradually move upward, the center position of the adsorption plate 3 is deformed upward and contracted, the matching hole 3.1 is reduced, and a seal is formed between the surrounding wall of the matching hole 3.1 and the surrounding wall of the suction cup frame 2.1, and a sealed cavity is formed between the bottom of the adsorption plate 3 and the surface of the substrate, so that the adsorption plate 3 can be adsorbed on the surface of the substrate.

[0065] After the above improvements, the operating mechanism 4 in the present application also has the characteristics of fewer parts, less space occupation, and compact structure;

[0066] In addition, the contact and cooperation mode between the driving surface 4.11 and the driving pin 4.2 is achieved by rotating the rotating frame 4.1 and changing the height of the driving pin 4.2 by the driving unit to realize the adsorption and desorption of the adsorption plate 3, which has the characteristics of simple operation, convenient use, stable and reliable operation.

[0067] Positioning grooves 4.111 are respectively provided at the highest and lowest ends of the driving surface 4.11. The transmission pin 4.2 moves into the positioning groove 4.111 and is fixed to the rotating frame 4.1, and the bracket 2 cannot move upward or downward. Of course, when external force intervenes and the rotating frame 4.1 is rotated by the handle, the transmission pin 4.2 can be moved out of the positioning groove 4.111.

[0068] The rotating frame 4.1 is connected with a handle. After the above improvement, the user rotates the rotating frame 4.1 through the handle, which is convenient to operate and has a good user experience.

[0069] The above are only preferred implementations of the utility model. The protection scope of the utility model is not limited to the above embodiments. All technical solutions under the idea of ​​the utility model belong to the protection scope of the utility model. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the utility model should also be regarded as the protection scope of the utility model.

Claims

1. A suction cup, characterized in that: include: A suction cup seat (1), wherein a bracket (2) is provided on the suction cup seat (1), and a suction cup frame (2.1) is provided at the lower end of the bracket (2); An elastic adsorption disc (3), wherein a matching hole (3.1) is provided at the bottom of the adsorption disc (3), the adsorption disc frame (2.1) is inserted into the matching hole (3.1) to support the adsorption disc (3), and the bracket (2) passes through the adsorption disc (3) upwards and is connected to the operating mechanism (4) on the adsorption disc seat (1); The operating mechanism (4) operates the bracket (2) and the suction cup frame (2.1) to rise, and the suction cup (3) is linked to rise, the edge of the suction cup (3) abuts against the blocking portion (1.1), the center of the suction cup (3) is deformed upward and retracted, the inner wall of the matching hole (3.1) is tightly attached to the suction cup frame (2.1) to form a seal, and the suction cup (3) is adsorbed on the substrate; The operating mechanism (4) operates the bracket (2) and the suction cup frame (2.1) to descend, and a gap is formed between the suction cup frame (2.1) and the inner wall of the matching hole (3.1) to allow air to enter between the adsorption plate (3) and the substrate to release the adsorption; An elastic member (5), one end of the elastic member (5) being stopped, and the other end being abutted against the upper end of the adsorption plate (3); when the adsorption plate (3) rises, the elastic member (5) is pre-tightened and abuts against the adsorption plate (3), so that the adsorption plate (3) is in close contact with the suction cup frame (2.1).

2. A suction cup according to claim 1, characterized in that: The elastic member (5) is a coil spring, which is sleeved on the outside of the bracket (2), with the upper end abutting against the suction cup seat (1) and the lower end abutting against the adsorption plate (3).

3. A suction cup according to claim 1, characterized in that: The suction cup frame (2.1) and the bracket (2) are integrally formed, and the suction cup frame (2.1) is arranged to extend radially outwards along the bracket (2).

4. A suction cup according to claim 1, characterized in that: The inner diameter of the matching hole (3.1) and the outer diameter of the suction cup frame (2.1) are both arranged in a structure that gradually increases from top to bottom, and the inner diameter of the matching hole (3.1) is larger than the outer diameter of the suction cup frame (2.1).

5. A suction cup according to claim 4, characterized in that: A first annular flange (6) is provided on the upper end surface of the suction cup frame (2.1) at a position close to the edge, and a second annular flange (7) is provided on the upper end surface of the suction cup frame (2.1) inside the first annular flange (6), a first fitting groove (8) is formed between the first annular flange (6) and the second annular flange (7), and a second fitting groove (9) is formed between the second annular flange (7) and the bracket (2); A first annular fitting block (3.2) and a second annular fitting block (3.3) are provided at the bottom of the matching hole (3.1); the first annular fitting block (3.2) is clearance-fitted with the first fitting groove (8); and the second annular fitting block (3.3) is clearance-fitted with the second fitting groove (9).

6. A suction cup according to claim 5, characterized in that: The bottom of the second fitting groove (9), the top of the first annular flange (6) and the top of the second annular flange (7) are respectively provided with notches (10) along the same radial direction, a gap is formed between the notch (10) and the surface of the suction cup (3) at the bottom of the matching hole (3.1), and the gap between the inner peripheral wall of the matching hole (3.1) and the outer peripheral wall of the suction cup frame (2.1) is connected to the notch (10) on the second annular flange (7).

7. A suction cup according to claim 5, characterized in that: The bottom of the second fitting groove (9) is provided with a pin body (9.1) protruding upwards, and the second annular fitting block (3.3) is provided with a connecting hole through which the pin body (9.1) can be inserted.

8. A suction cup according to claim 5, characterized in that: The cross sections of the first annular fitting block (3.2) and the second annular fitting block (3.3) are both of a structure that is wide at the top and narrow at the bottom.

9. A suction cup according to claim 1, characterized in that: The adsorption disk (3) is provided with an assembly space (1.2), the elastic member (5), the suction disk frame (2.1) and the adsorption disk (3) are arranged in the assembly space (1.2), and the annular flange arranged at the edge of the bottom opening of the assembly space (1.2) is the blocking portion (1.1).

10. A suction cup according to claim 1, characterized in that: The operating mechanism (4) comprises: A rotating frame (4.1), the rotating frame (4.1) being rotatably arranged on the suction cup seat (1), the upper end of the bracket (2) passing through the inner side of the rotating frame (4.1), the upper end of the bracket (2) being provided with a driving pin (4.2), the rotating frame (4.1) being provided with an inclined driving surface (4.11) whose height gradually decreases from high to low, the driving pin (4.2) being in contact with the driving surface (4.11), and the driving surface (4.11) being coaxially arranged with the rotating frame (4.1); Rotating the rotating frame (4.1) to switch to a higher driving surface (4.11) to contact the driving pin (4.2) to drive the bracket (2) to rise; The rotating frame (4.1) is rotated to switch to a driving surface (4.11) with a lower height to cooperate with the driving pin (4.2) to drive the bracket (2) to descend.

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