Reciprocating type cleaning dust collector
By using the alternate working design of active swing brush and follower swing brush in the vacuum cleaner, combined with adhesive brush and scraping cloth, the problems of complex transmission structure and poor cleaning effect of the existing vacuum cleaner are solved, and efficient hair and dust cleaning is achieved. Small, lightweight cleaning effect.
Patent Information
- Application Number
- CN202420957241.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-06
- Publication Date
- 2024-12-20
- Estimated Expiration
- 2034-05-06
AI Technical Summary
The swing brush transmission structure of existing electric vacuum cleaners is complex, which leads to high production cost and poor cleaning effect, and it is difficult to effectively remove debris accumulated over a long period of time, affecting the cleaning effect.
A reciprocating cleaning vacuum cleaner is designed, using active swing brushes and follower swing brushes to alternately work, combining glue brushes and scrapers to provide air ducts through the air inlet, and using torsion springs to maintain the compression force of the follower swing brushes to achieve more effective hair and dust are cleaned, simplifying the transmission structure.
It improves cleaning efficiency, reduces hair tangling and dust flying, is small in size, light in weight, and is thorough in cleaning, solving the problems of high price of electric roller brushes and difficult to clean hair tangling.
Smart Images
Figure CN222194885U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of dust removal equipment and relates to a dust collector, in particular to a reciprocating cleaning dust collector. Background Art
[0002] Vacuum cleaners can be divided into vertical, horizontal and portable types according to their structure. The working principle of a vacuum cleaner is to use an electric motor to drive the blades to rotate at high speed, generate negative air pressure in a sealed shell, and absorb dust.
[0003] The oscillating brush in the existing electric vacuum cleaner is driven by electricity to reciprocate, so there are problems such as high price of the electric roller brush, difficulty in cleaning entangled hair, and large size.
[0004] For example, patent document EP2005026860 discloses an upright vacuum cleaner with an oscillating brush (60). The upright vacuum cleaner comprises an upright vacuum cleaner body (10) having a suction nozzle (11), a driving unit (20) installed in the vacuum cleaner body (10) for moving the vacuum cleaner body (10) forward and backward, a gripping unit (30) slidably installed on the upper end of the vacuum cleaner body (10), the gripping unit (30) having a sensor (31) for sensing the sliding direction of the gripping unit (30), and a control unit (40) for controlling the sliding direction of the gripping unit (30). The driving unit (50) is operated according to information sensed by the sensor (31) to move the vacuum cleaner body (10) forward or backward, the motion conversion unit (50) is used to convert the rotational motion of the driving unit (20) into angular reciprocating motion, and the oscillating brush (60) connected to the motion conversion unit (50) is used to perform angular reciprocating motion. The oscillating brush (60) is installed in the suction nozzle (11) of the vacuum cleaner body (10) and is in contact with the floor.
[0005] In the above technical solution, although the motion conversion unit and the conversion drive unit are used to realize the reciprocating drive of the swing brush, there are still complex problems in the transmission structure, which increases the production cost, and the complex transmission structure will lead to poor stability of the reciprocating motion of the swing brush. In addition, the above technical solution lacks the dust removal structure and function of the cleaning structure, so that the debris accumulated on the swing brush for a long time cannot be removed in time, resulting in poor subsequent cleaning effect. Utility Model Content
[0006] The utility model aims to solve the above problems in the prior art and proposes a reciprocating cleaning vacuum cleaner.
[0007] The objectives of the utility model can be achieved through the following technical solutions: a reciprocating cleaning vacuum cleaner, comprising a dust collection cylinder shell with a cleaning port at the bottom, a rubber brush A is arranged on the front side of the cleaning port of the dust collection cylinder shell, a rubber brush B is arranged on the rear side of the cleaning port of the dust collection cylinder shell, an active swinging brush is hinged in the dust collection cylinder shell, the active swinging brush has a semi-cylinder cavity connected to the dust collection cylinder shell, an air inlet connected to the semi-cylinder cavity is arranged at the bottom of the active swinging brush, a brush cloth A is attached to the outer wall of the active swinging brush on the front side of the air inlet, a brush cloth B is attached to the outer wall of the active swinging brush on the rear side of the air inlet, the air inlet and the brush cloth A and / or the brush cloth B are exposed from the cleaning port, a driven swinging brush A is arranged in the dust collection cylinder shell corresponding to the brush cloth A, and a driven swinging brush B is arranged in the dust collection cylinder shell corresponding to the brush cloth B.
[0008] The dust collection cylinder shell comprises an upper cover and a base which are assembled up and down, wherein the upper cover and the base are assembled to form an internal dust collection cylinder cavity, the bottom of the base is provided with the cleaning port, and the top of the upper cover is connected to the dust collection duct.
[0009] In the above-mentioned reciprocating cleaning vacuum cleaner, the active oscillating brush is a semi-cylinder shell, a notch is set on the top surface of the semi-cylinder shell, the semi-cylinder cavity is connected to the dust cylinder cavity of the dust cylinder shell through the notch, the air inlet is opened in the middle of the arc wall of the semi-cylinder shell, and the long strip-shaped air inlet is arranged along the axis of the semi-cylinder shell.
[0010] In the above-mentioned reciprocating cleaning vacuum cleaner, shaft pins are protrudingly provided at both ends of the semi-cylinder shell, and mounting holes are correspondingly provided at both ends of the base, and the shaft pins are correspondingly inserted into the mounting holes to form a rotational connection.
[0011] In the above-mentioned reciprocating cleaning vacuum cleaner, a plurality of bristles A are arranged on the brush cloth A, and the bristles A are arranged to be inclined outward and upward.
[0012] In the above-mentioned reciprocating cleaning vacuum cleaner, the driven swing brush A includes a long curved brush plate A, on the inner curved wall surface of which a scraping cloth A is fixed, and a plurality of scraping bristles A are arranged on the scraping cloth A. The scraping bristles A are arranged inwardly and upwardly, and the scraping bristles A and the brush bristles A form an upward crossing angle.
[0013] In the above-mentioned reciprocating cleaning vacuum cleaner, a plurality of bristles B are arranged on the brush cloth B, and the bristles B are arranged to be inclined outward and upward.
[0014] In the above-mentioned reciprocating cleaning vacuum cleaner, the driven swing brush B includes a long curved brush plate B, on the inner curved wall of the curved brush plate B is fixedly attached a scraping cloth B, on the scraping cloth B are arranged a number of scraping bristles B, the scraping bristles B are arranged inwardly and upwardly, and the scraping bristles B and the brush bristles B form an upward crossing angle.
[0015] In the above-mentioned reciprocating cleaning vacuum cleaner, the bottom edges of both ends of the driven swing brush A / the driven swing brush B protrude outward to form a coaxial rotating shaft, and the top edges of both ends of the driven swing brush A / the driven swing brush B protrude outward to form a coaxial swing shaft; a rotating hole is correspondingly arranged on the inner wall of the base, and the coaxial rotating shaft is inserted into the rotating hole to form a rotating connection, and an arc groove is correspondingly arranged on the inner wall of the upper cover, and the coaxial swing shaft is embedded in the arc groove to form a swinging connection.
[0016] In the above-mentioned reciprocating cleaning vacuum cleaner, a torsion spring is fixedly sleeved on the coaxial rotating shaft, and the rotating hole expands outward to form two stop surfaces, and the rotating arms of the torsion spring press against the stop surfaces one by one.
[0017] Compared with the prior art, the reciprocating cleaning vacuum cleaner has the following beneficial effects:
[0018] 1. The brush cloths A and B on the active swing brush work alternately and cooperate with the brush cloth on the driven swing brush to clean hair and other tasks, thereby improving cleaning efficiency; the torsion spring on the driven swing brush ensures that the top of the driven swing brush always maintains a certain pressing force with the active swing brush, thereby cleaning hair more effectively.
[0019] 2. Dust is cleaned by alternately working with rubber brushes A and B; the air inlet provides an air duct. At the same time, if there is hair embedded on the brush cloths A and B on the active swing brush, the hair can be removed or cut off with fingers or small tools, and then the swing brush completes the cleaning; combined with the vacuum function, dust can be effectively avoided from flying during cleaning.
[0020] In summary, the utility model integrates multiple functions such as cleaning hair and sweeping dust, and has multiple advantages such as small size, light weight, economical and practical, and thorough cleaning, etc. It improves the problems of electric roller brushes such as high price, difficult to clean hair entanglement, and large size. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 This is a three-dimensional structural diagram of the overall appearance of the reciprocating cleaning vacuum cleaner.
[0022] Figure 2 This is an exploded three-dimensional structural diagram of the reciprocating cleaning vacuum cleaner.
[0023] Figure 3 This is a diagram of the front push bottom surface of the reciprocating cleaning vacuum cleaner.
[0024] Figure 4 This is a forward push cross-sectional state diagram of the reciprocating cleaning vacuum cleaner.
[0025] Figure 5 This is a diagram of the bottom surface of the reciprocating cleaning vacuum cleaner when it is pulled back.
[0026] Figure 6This is a rear-pull cross-sectional state diagram of the reciprocating cleaning vacuum cleaner.
[0027] Figure 7 The present invention is a flow chart of the cleaning actions of brushing and scraping in the reciprocating cleaning vacuum cleaner.
[0028] In the figure, 1. dust suction duct; 2. upper cover; 3. base; 4. rubber brush A; 5. rubber brush B; 6. active swing brush; 6a. air inlet; 7. brush cloth A; 8. brush cloth B; 8a. bristles B; 9. driven swing brush A; 10. scraping cloth A; 11. driven swing brush B; 12. scraping cloth B; 12a. scraping bristles B; 13. coaxial rotating shaft; 14. coaxial swing shaft; 15. torsion spring. DETAILED DESCRIPTION
[0029] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.
[0030] like Figures 1 to 7 As shown, the reciprocating cleaning vacuum cleaner includes a dust cylinder shell with a cleaning port at the bottom, a rubber brush A4 is arranged on the front side of the cleaning port of the dust cylinder shell, a rubber brush B5 is arranged on the rear side of the cleaning port of the dust cylinder shell, an active swing brush 6 is hinged in the dust cylinder shell, the active swing brush 6 has a semi-cylinder cavity connected to the dust cylinder shell, an air inlet 6a connected to the semi-cylinder cavity is arranged at the bottom of the active swing brush 6, a brush cloth A7 is attached to the outer wall of the active swing brush 6 on the front side of the air inlet 6a, a brush cloth B8 is attached to the outer wall of the active swing brush 6 on the rear side of the air inlet 6a, the air inlet 6a and the brush cloth A7 and / or brush cloth B8 are exposed from the cleaning port, a driven swing brush A9 is arranged in the dust cylinder shell corresponding to the brush cloth A7, and a driven swing brush B11 is arranged in the dust cylinder shell corresponding to the brush cloth B8.
[0031] like Figure 2 As shown, the dust collection cylinder shell includes an upper cover 2 and a base 3 assembled in an upper and lower manner, the upper cover 2 and the base 3 are assembled to form an internal dust collection cylinder cavity, a cleaning port is provided at the bottom of the base 3, and the top of the upper cover 2 is connected to the dust collection pipe 1. The upper cover 2 is a semi-cylindrical shell, and the lower cover has a bottom surface flush with the cleaning port. The upper cover 2 and the base 3 are assembled and connected by a plurality of screws, and after the upper cover 2 and the base 3 are assembled, a horizontally placed dust collection cylinder cavity similar to a cylinder is formed.
[0032] The active swing brush 6 is a semi-cylinder shell, and a notch is set on the top surface of the semi-cylinder shell. The semi-cylinder cavity is connected to the dust cylinder cavity of the dust cylinder shell through the notch. The air inlet 6a is set in the middle of the arc wall of the semi-cylinder shell, and the long strip-shaped air inlet 6a is arranged along the axis of the semi-cylinder shell. The air inlet 6a is always located within the range of the cleaning port, so that in the working state, the wind flow must maintain the suction state. The wind flow drives dust and debris into the semi-cylinder cavity through the air inlet 6a, and finally passes through the dust cylinder cavity of the dust cylinder shell and is sucked into the dust cup by the dust suction pipe 1.
[0033] Axle pins are protruding from both ends of the semi-cylinder housing, and mounting holes are correspondingly provided at both ends of the base 3, and the axle pins are correspondingly connected through the mounting holes to form a rotation connection. The axle pins are located at the center of the semi-cylinder housing, and by setting the rotation connection, under the action of the reciprocating friction force, the active swing brush 6 can swing alternately clockwise and counterclockwise within a certain angle range.
[0034] like Figure 7 As shown, a plurality of bristles A are arranged on the brush cloth A7, and the bristles A are arranged to be tilted outward and upward. An acute angle upward is formed between the bristles A and the brush cloth A7, so that when the dust collection cylinder shell is pushed forward, under the action of friction, the active swing brush 6 drives the bristles A to move relatively backward, so that all the bristles A move from the dust collection cylinder shell to the cleaning port to contact the outside world, and when the dust collection cylinder shell is pulled backward, all the bristles A gradually enter the dust collection cylinder shell, and the bristles A hook the hair, cotton wool, etc. on the surface of the object and bring them into the dust collection cylinder shell.
[0035] like Figure 2 , 4 As shown in Figures 6 and 7, the driven swing brush A9 includes a long curved brush plate A, on the inner curved wall of the curved brush plate A, a scraping cloth A10 is fixed, and a plurality of scraping bristles A are arranged on the scraping cloth A10, and the scraping bristles A are arranged inwardly and upwardly, and the scraping bristles A and the brush bristles A form an upward crossing angle. An upward acute angle is formed between the scraping bristles A and the scraping cloth A10, and after the brush bristles A carry debris into the dust collection cylinder shell, when the brush bristles A move from the dust collection cylinder shell to the cleaning port again, the scraping bristles A are gradually inserted upward into the brush bristles A, and the debris is hooked out of the brush bristles A and separated from the dust collection cylinder shell, and further falls into the semi-circular bin of the active swing brush 6.
[0036] like Figure 7 As shown, a plurality of bristles B8a are arranged on the brush cloth B8, and the bristles B8a are arranged to be tilted outward and upward. An acute angle upward is formed between the bristles B8a and the brush cloth B8, so that when the dust collection tube shell is pulled backward, under the action of friction, the active swing brush 6 drives the bristles B8a to move forward relatively, so that all the bristles B8a move from the dust collection tube shell to the cleaning port to contact the outside world, and when the dust collection tube shell is pushed forward, all the bristles B8a gradually enter the dust collection tube shell, and the bristles B8a hook the hair, cotton wool, etc. on the surface of the object and bring them into the dust collection tube shell.
[0037] like Figure 2 , 4As shown in Figures 6 and 7, the driven swing brush B11 includes a long curved brush plate B, a scraping cloth B12 is fixedly attached to the inner curved wall of the curved brush plate B, and a plurality of scraping bristles B12a are arranged on the scraping cloth B12. The scraping bristles B12a are tilted inward and upward, and the scraping bristles B12a and the brush bristles B8a form an upward crossing angle. An upward acute angle is formed between the scraping bristles B12a and the scraping cloth B12. After the brush bristles B8a carry debris into the dust collection cylinder shell, when the brush bristles B8a move from the dust collection cylinder shell to the cleaning port again, the scraping bristles B12a are gradually inserted into the brush bristles B8a upward, and the debris is hooked out of the brush bristles B8a and separated into the dust collection cylinder shell, and further falls into the semi-circular silo of the active swing brush 6.
[0038] The length of the brush cloth on the active oscillating brush 6 is shorter than the scraping cloth on the driven oscillating brush, so that the hair brushed onto the active oscillating brush 6 can be cleaned more effectively.
[0039] like Figure 2 As shown, the bottom edges of both ends of the driven swing brush A9 / driven swing brush B11 protrude outward to form a coaxial rotating shaft 13, and the top edges of both ends of the driven swing brush A9 / driven swing brush B11 protrude outward to form a coaxial swing shaft 14; a corresponding rotating hole is set on the inner wall of the base 3, and the coaxial rotating shaft 13 is inserted into the rotating hole to form a rotating connection, and an arc groove is set on the inner wall of the upper cover 2, and the coaxial swing shaft 14 is embedded in the arc groove to form a swing connection. The bottom edge of the long curved arc brush plate is used as the center of the circle, the width as the radius, and the top edge as the end of the radius. The bottom edge rotates to drive the top edge to swing back and forth, so that the driven swing brush A9 / driven swing brush B11 can realize the swinging activity within a certain angle range, thereby avoiding the driven swing brush A9 / driven swing brush B11 from getting stuck with the active swing brush 6, which makes the active swing brush 6 unable to rotate and clean.
[0040] The torsion spring 15 is fixedly sleeved on the coaxial rotating shaft 13, and the rotating hole expands outward to form two stop surfaces, and the rotating arms of the torsion spring 15 press against the stop surfaces one by one. The torsion spring 15 enables the driven swing brush A9 / driven swing brush B11 to form elastic pre-tightening pressure on the brush cloth A7 / brush cloth B8, so that the scraper can effectively insert the bristles during the relative movement, which is conducive to hooking out the sundries mixed in the bristles, improving the cleaning effect, and further maintaining the continuous cleaning ability of the bristles.
[0041] The operation method of this reciprocating cleaning vacuum cleaner is:
[0042] like Figure 3 , 4 As shown, 1. When the dust collecting shell is pushed forward, the active swing brush 6 drives the bristles A to move relatively backward under the action of friction, so that all the bristles A move from the dust collecting shell to the cleaning port to contact the outside. At the same time, the rubber brush B5 sweeps the dust and sucks the dust into the dust cup through the air inlet 6a.
[0043] like Figure 5 , 67, 2. Pull the dust collection shell backwards, and when all the bristles A gradually enter the dust collection shell, the bristles A hook the hair, cotton wool, etc. on the surface of the object and bring them into the dust collection shell. At the same time, under the action of friction, the active swing brush 6 drives the bristles B8a to move forward relatively, so that all the bristles B8a move from the dust collection shell to the cleaning port to contact the outside world. At the same time, the rubber brush A4 sweeps the dust and sucks the dust into the dust cup through the air inlet 6a.
[0044] like Figure 3 , 4 As shown in FIG7, 3, the dust collection shell is pushed forward again. When the bristles A move from the dust collection shell to the cleaning port again, the scraper A is gradually inserted upward into the bristles A, and the debris is hooked out of the bristles A and separated into the dust collection shell, and further falls into the semi-circular silo of the active swing brush 6. At the same time, when all the bristles B8a gradually enter the dust collection shell, the bristles B8a hook the hair, cotton wool, etc. on the surface of the object and bring them into the dust collection shell. At the same time, the rubber brush B5 sweeps the dust and sucks the dust into the dust cup through the air inlet 6a.
[0045] like Figure 5 , 6 As shown in FIG. 7, 4. Pull the dust collection shell backward again. When the bristles B8a move from the dust collection shell to the cleaning port again, the scraper bristles B12a are gradually inserted upward into the bristles B8a, and the debris is hooked out of the bristles B8a and separated into the dust collection shell, and further falls into the semi-circular silo of the active swing brush 6. At the same time, when all the bristles A gradually enter the dust collection shell, the bristles A hook the hair, cotton wool, etc. on the surface of the object and bring them into the dust collection shell. At the same time, the rubber brush A4 sweeps the dust and sucks the dust into the dust cup through the air inlet 6a.
[0046] 5. The dust collector shell is repeatedly pushed and pulled back and forth to form multiple cycles of cleaning. Through the combination of suction and hooking, the debris on the surface of the object is completely removed.
[0047] The specific embodiments described herein are merely examples of the spirit of the utility model. A person skilled in the art of the utility model may make various modifications or supplements to the specific embodiments described or replace them in a similar manner, but will not deviate from the spirit of the utility model or exceed the defined scope. Although the utility model is described and described in detail in the drawings and the foregoing description, such descriptions and descriptions are considered to be illustrative or exemplary rather than restrictive. It should be understood that within the scope of the following claims, changes and modifications may be made by a person of ordinary skill. Specifically, the utility model covers additional embodiments having any combination of features from the above-mentioned different embodiments. In terms of the use of the expression "generally" or "substantially", this patent application should be understood to disclose that these features and values are also fully satisfied, that is, there is no aforementioned characterization as "generally" or "substantially".
[0048] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
Claims
1. A reciprocating vacuum cleaner, comprising a vacuum housing having a cleaning port at the bottom, wherein a rubber brush A is arranged at the front side of the cleaning port, and a rubber brush B is arranged at the rear side of the cleaning port, wherein: An active swinging brush is hinged in the dust collection cylinder shell, and the active swinging brush has a half-cylinder cavity connected to the dust collection cylinder shell, and an air inlet connected to the half-cylinder cavity is arranged at the bottom of the active swinging brush. A brush cloth A is attached to the outer wall of the active swinging brush in front of the air inlet, and a brush cloth B is attached to the outer wall of the active swinging brush in the rear side of the air inlet. The air inlet and the brush cloth A and / or the brush cloth B are exposed from the cleaning port, and a driven swinging brush A is arranged in the dust collection cylinder shell corresponding to the brush cloth A, and a driven swinging brush B is arranged in the dust collection cylinder shell corresponding to the brush cloth B.
2. The reciprocating cleaning vacuum cleaner according to claim 1, characterized in that: The dust collection cylinder shell comprises an upper cover and a base which are assembled in an upper and lower manner, wherein the upper cover and the base are assembled to form an internal dust collection cylinder cavity, the bottom of the base is provided with the cleaning port, and the top of the upper cover is connected to a dust collection duct.
3. The reciprocating cleaning vacuum cleaner according to claim 2, characterized in that: The active oscillating brush is a semi-cylinder shell, a notch is arranged on the top surface of the semi-cylinder shell, the semi-cylinder cavity is connected to the dust collection cylinder cavity of the dust collection cylinder shell through the notch, the air inlet is opened in the middle of the arc wall of the semi-cylinder shell, and the long strip-shaped air inlet is arranged along the axis of the semi-cylinder shell.
4. The reciprocating cleaning vacuum cleaner according to claim 3, characterized in that: Axial pins are protrudingly arranged at both ends of the semi-cylinder shell, and mounting holes are correspondingly provided at both ends of the base, and the axial pins are correspondingly passed through the mounting holes to form a rotational connection.
5. The reciprocating cleaning vacuum cleaner according to claim 1, characterized in that: A plurality of bristles A are arranged on the brush cloth A, and the bristles A are arranged to be inclined outward and upward.
6. The reciprocating cleaning vacuum cleaner according to claim 5, characterized in that: The driven swing brush A comprises a long curved brush plate A, on the inner curved wall of which a scraping cloth A is fixed, and on the scraping cloth A a plurality of scraping bristles A are arranged, and the scraping bristles A are arranged upward and inwardly inclined, and the scraping bristles A and the brush bristles A form an upward crossing angle.
7. The reciprocating cleaning vacuum cleaner according to claim 1, characterized in that: A plurality of bristles B are arranged on the brush cloth B, and the bristles B are arranged to be inclined outward and upward.
8. The reciprocating cleaning vacuum cleaner according to claim 7, characterized in that: The driven swing brush B includes a long curved brush plate B, on the inner curved wall of which a scraping cloth B is fixedly attached. A plurality of scraping bristles B are arranged on the scraping cloth B. The scraping bristles B are arranged upward and inwardly inclined, and the scraping bristles B and the brush bristles B form an upward crossing angle.
9. The reciprocating cleaning vacuum cleaner according to claim 2, characterized in that: The bottom edges at both ends of the driven oscillating brush A / the driven oscillating brush B protrude outward to form a coaxial rotating shaft, and the top edges at both ends of the driven oscillating brush A / the driven oscillating brush B protrude outward to form a coaxial swing shaft; a rotating hole is correspondingly arranged on the inner wall of the base, and the coaxial rotating shaft penetrates into the rotating hole to form a rotating connection, and an arc groove is correspondingly arranged on the inner wall of the upper cover, and the coaxial swing shaft is embedded in the arc groove to form a swinging connection.
10. The reciprocating cleaning vacuum cleaner according to claim 9, characterized in that: A torsion spring is fixedly sleeved on the coaxial rotating shaft, and the rotating hole is expanded outward to form two stop surfaces, and the rotating arms of the torsion spring are pressed against the stop surfaces in a one-to-one correspondence.