Pressing type coating tool

By optimizing the pressing linkage of the press-type coating tool through integrated molding of linkage components and fixed mating structure, the problems of insensitive pressing and uneven correction are solved, thereby improving the tool's operational sensitivity and service life.

CN223970328UActive Publication Date: 2026-03-06QINGDAO YATAN STATIONERY CO LTD
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Utility models(China)
Current Assignee / Owner
Filing Date
2025-03-12
Publication Date
2026-03-06

AI Technical Summary

Technical Problem

Existing press-type coating tools have problems such as insensitive pressing, jamming, and uneven correction effects. In particular, they require a lot of force when pressing and may leave residue of correction tape or dot glue.

Method used

An integrally molded linkage component is used as the transmission component for the pressing action. The pressing linkage structure is optimized through the fixed fit between the linkage component, the outer shell, and the pressing component. Combined with the guide and limit structure, the smooth sliding and resetting of the pressing component and the inner core are ensured.

Benefits of technology

It improves the sensitivity and reliability of press-type coating tools, reduces production difficulty, extends service life, and avoids jamming and residue of correction tape or dot glue.

✦ Generated by Eureka AI based on patent content.

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Abstract

The utility model discloses a push-type coating tool, which relates to the field of stationery and adopts the technical scheme that the push-type coating tool comprises a shell with a cavity inside and an external holding structure of the coating tool; the pressing piece is arranged at one end of the shell and is in sliding connection with the shell; the inner core is in sliding connection with the shell; the linkage piece is arranged in the shell, and the linkage piece is movably connected with the shell; the inner core comprises an inner shell, and a coating assembly is arranged at one end of the inner shell. The linkage piece is integrally formed, and matching structures are fixedly arranged in the pressing piece and the shell and correspond to the linkage piece respectively. The pressing piece can drive the coating assembly of the inner core to stretch out or retract at the end opening of the shell through the linkage piece. Compared with the prior art, the press linkage structure has the beneficial effects that the press linkage structure is optimized by changing the form of the press linkage structure, using the integrally formed linkage piece as a transmission piece of the press action and directly processing other structures matched with the linkage piece in the shell and the press piece in a fixed forming manner.
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Description

Technical Field

[0001] This utility model relates to the field of stationery, specifically a press-type coating tool. Background Technology

[0002] Press-type coating tools, as an innovative product in the stationery market, are welcomed by a wide range of users for their unique operation and convenient user experience. However, existing press-type coating tools on the market still have some problems and shortcomings.

[0003] Common press-type coating tools often suffer from issues such as insensitive pressing and the internal correction band getting stuck during pressing. Some press-type coating tools have insufficient sensitivity in their pressing mechanism, requiring significant force to activate. Furthermore, they may fail to smoothly return to their original position after pressing.

[0004] In addition, uneven correction results are a common problem with existing press-type coating tools. Improper control of the correction tape core's output speed or pressure can lead to unevenness on the corrected paper surface or correction tape residue, affecting the correction effect. The same problem exists with press-type dot adhesive products. Utility Model Content

[0005] To address one of the shortcomings of existing technologies, this utility model provides a press-type coating tool to solve the structural defects of correction tape and dot glue.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a press-type coating tool, comprising:

[0007] The outer shell, with an internal cavity, serves as the external gripping structure for this coating tool;

[0008] A pressing component is disposed at one end of the housing and is slidably connected to the housing;

[0009] The inner core is the coating tool body, and the inner core and the outer shell are slidably connected.

[0010] A linkage component is disposed inside the housing, and the linkage component is movably connected to the housing.

[0011] The inner core includes an inner shell, and a coating assembly is provided at one end of the inner shell;

[0012] The linkage component is integrally formed, and the pressing component and the corresponding linkage component inside the outer shell are respectively fixedly provided with a mating structure; the pressing component can drive the coating component of the inner core to extend or retract at the port of the outer shell through the linkage component.

[0013] Preferably, the housing comprises:

[0014] Half part one is slidably connected to the pressing member, the linkage member is disposed inside the half part one, and a first mating structure is provided inside the half part one corresponding to the linkage member;

[0015] Half two, the inner core is disposed inside half two; one end of half two is connected to half one, and the other end is provided with an open opening for the coating assembly of the inner core to extend out.

[0016] Preferably, the opposite sides of half one and half two are hinged together, and the other side is snapped together by a snap-fit ​​structure.

[0017] Preferably, the inner core further includes:

[0018] A reset assembly, disposed between the inner shell and half one, provides a reset force to the inner core to retract into half two.

[0019] Preferably, the coating assembly includes:

[0020] The end frame is detachably connected to the inner shell;

[0021] The coating component is a cylindrical roller, which is rotatably connected to the end frame.

[0022] Preferably, the inner shell comprises:

[0023] The unwinding roller is located inside the inner shell and is rotatably connected to the inner shell;

[0024] The take-up roller is located inside the inner shell and is rotatably connected to the inner shell; the take-up roller and the unwind roller are linked by a gear set.

[0025] The belt has its two ends wrapped around the unwinding roller and the take-up roller, respectively, and the belt passes around the coating component. The material coating surface of the belt faces the side of the coating component away from the inner shell.

[0026] Preferably, the interior of the first half is a cavity, and a space is provided between the first half and the pressing member:

[0027] The guide structure and the pressing part are slidably connected through the guide structure and the half part. The guiding direction of the guide structure is parallel to the sliding direction of the inner core.

[0028] The limiting structure can limit the sliding path of the pressing component.

[0029] Preferably, the linkage component includes:

[0030] The main body of the linkage is a cylinder with a cylindrical cavity inside;

[0031] The first linkage part is located at the end of the linkage body away from the inner core, and the first linkage part is a ring-shaped set of teeth;

[0032] The second linkage part is located on the periphery of the linkage body and is located near the inner core of the linkage body. The second linkage part includes several protrusions, the length direction of the protrusions is parallel to the sliding direction of the inner core, and the protrusions are evenly distributed in a circular array around the linkage body. The end of the protrusion away from the inner core is provided with an inclined surface.

[0033] Preferably, the first mating structure includes:

[0034] The matching cylinder is a hollow cylindrical body that is fixedly installed inside the first half.

[0035] The sliding groove is a through groove formed inside the mating cylinder, and its through direction is parallel to the sliding direction of the inner core; the protrusion of the second linkage part can be inserted into the sliding groove; the number of sliding grooves corresponds to the number of protrusions;

[0036] A positioning groove is formed between two adjacent sliding grooves, and the shape of the positioning groove corresponds to the beveled end of the protrusion of the second linkage part.

[0037] Preferably, the pressing member has a second mating structure inside, the second mating structure including:

[0038] The mating column is a column body. One end of the mating column is fixedly connected to the inner wall of the pressing component, and the other end is set towards the linkage component. The linkage body can be sleeved on the outside of the mating column.

[0039] The pushing part is located on the outer side of the end of the mating column, and the pushing part is a toothed structure corresponding to the second linkage part.

[0040] Compared with existing technologies, this solution offers the following advantages: By modifying the form of the pressing linkage structure, this solution utilizes an integrally molded linkage component as the transmission element for the pressing action. Simultaneously, the structures of other cooperating linkage components are directly machined into the outer shell and the pressing component using a fixed molding method, thereby optimizing the pressing linkage structure. This reduces the manufacturing difficulty of the linkage components and improves the operational reliability of the linkage structure, extending its service life. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application. Figure 1 ;

[0042] Figure 2 This is a schematic diagram of the overall structure of an embodiment of this application. Figure 2 ;

[0043] Figure 3 Explosions in embodiments of this application Figure 1 ;

[0044] Figure 4 for Figure 3 A magnified view of part A;

[0045] Figure 5 This is a schematic diagram of the internal structure of the core;

[0046] Figure 6 Explosions in embodiments of this application Figure 2 ;

[0047] Figure 7 This is a schematic diagram of the linkage structure according to an embodiment of this application;

[0048] Figure 8 This is a schematic diagram of the internal section of one half of an embodiment of this application;

[0049] Figure 9 This is a schematic internal cross-sectional view of the pressing component according to an embodiment of this application.

[0050] In the picture:

[0051] 1. Outer shell; 11. Half part one; 12. Half part two; 13. Snap-fit ​​structure; 2. Pressing component; 3. Inner core; 31. Inner shell; 311. Unwinding roller; 312. Rewinding roller; 313. Pressing groove; 32. Coating assembly; 321. End frame; 322. Coating component; 33. Reset assembly; 4. Linkage component; 41. Linkage body; 42. First linkage part; 43. Second linkage part; 44. Limiting block; 5. First mating structure; 51. Mating cylinder; 52. Sliding groove; 53. Positioning groove; 6. Second mating structure; 61. Mating column; 62. Pushing part; 7. Guide structure; 71. Guide groove; 72. Guide block; 8. Limiting structure; 81. Limiting slide; 82. Limiting hook. Detailed Implementation

[0052] The technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0053] Please see Figures 1-3 This application provides the following technical solutions:

[0054] A press-type coating tool includes a housing 1 with an internal cavity, serving as the external gripping structure for the coating tool. A pressing element 2 is slidably connected to one end of the housing 1. An inner core 3 is slidably connected inside the housing 1, forming the coating tool body. The inner core 3 includes an inner shell 31, with a coating assembly 32 disposed at one end of the inner shell 31. The interior of the inner shell 3 can be fitted with correction tape or dot glue. A linkage 4 is also disposed inside the housing 1, movably connected to the housing 1, and located between the pressing element 2 and the inner core 3.

[0055] The linkage component 4 adopts an integral molding structure. The pressing component 2 and the corresponding linkage component 4 are respectively fixedly provided with matching structures inside the outer shell 1. The pressing component 2 can drive the coating component 32 of the inner core 3 to extend or retract at the port of the outer shell 1 through the linkage component 4.

[0056] Unlike traditional press-type structures, which use two separate components linked together, this design requires both components to be coaxial and able to rotate and slide freely. Research has shown that this connection method is the main cause of jamming during the use of press-type correction tapes. This is due to damage to the two components or problems with the coaxial position at the connection point. Therefore, this solution replaces the linkage structure at the press point with a one-piece molded linkage component 4. The linkage component 4, the outer shell 1, and the press component 2 work together to achieve linkage, thus avoiding the failure problems of traditional press-type structures.

[0057] Based on the above implementation scheme, the outer shell 1 is composed of half-section 11 and half-section 2. Half-section 11 is slidably connected to the pressing member 2, and the linkage member 4 is disposed inside half-section 11, with a first mating structure 5 disposed inside half-section 11 corresponding to the linkage member 4. The inner core 3 is disposed inside half-section 2; one end of half-section 2 is connected to half-section 11, and the other end is provided with an opening for the coating assembly 32 of the inner core 3 to extend out.

[0058] Half-section 12 is larger than half-section 11. Half-section 12 is the main gripping structure when using this coating device, and an anti-slip structure is provided on the outer side of half-section 12. The anti-slip structure can be an anti-slip strip or an anti-slip groove.

[0059] Different connection methods can be used between half-part 11 and half-part 2 12, as long as they can be detachably connected.

[0060] Based on the above implementation scheme, the first half 11 and the second half 12 of this scheme are connected by hinges. The two sides are hinged on opposite sides and snapped together by snap-fit ​​structure 13 on the other side.

[0061] The snap-fit ​​structure 13 includes a snap-fit ​​block on half 11 and a snap-fit ​​groove on half 2 12. The groove is a through groove, and when half 11 and half 2 12 are engaged, the snap-fit ​​block is inserted into the groove. When it is necessary to open half 11 and half 2 12, simply press the snap-fit ​​block down to disengage it from the groove, and then rotate half 11. By opening half 11, the internal core 3 can be replaced.

[0062] Based on the above implementation scheme, the inner core 3 also includes a reset component 33, which is disposed between the inner shell 31 and the first half 11, and can provide a reset force for the inner core 3 to retract into the second half 12.

[0063] The reset assembly 33 allows the inner core 3 to retract inside the second half 12 when the pressing member 2 is not pressing it. It can take various forms; this solution provides one example as follows.

[0064] See Figure 4 A through groove is formed on the inner core 3, and a sliding member is installed in the through groove. The sliding member is "H"-shaped, with its two parallel parts located outside the through groove of the inner core 3 and its middle part located inside the through groove. A limiting boss is provided on the inner wall of the second half 12 corresponding to the sliding member, and the part of the sliding member located outside the inner core 3 abuts against the limiting boss. A spring is installed between the middle part of the sliding member and the inner wall of the through groove of the inner core 3. When the pressing member 2 drives the inner core 3 to slide, causing the coating assembly 32 to extend out of the second half 12, the spring is compressed. When the pressing member 2 no longer maintains the force on the inner core 3, the spring returns to its original position, pushing the inner core 3 back to its original position.

[0065] Based on the above implementation plan, see Figure 4 To address the jamming issue during coating, this solution also improves the coating assembly 32. The coating assembly 32 includes an end frame 321 and a coating element 322. The end frame 321 and the inner shell 31 of the inner core 3 are detachably connected. The coating element 322 is a cylindrical roller, and it is rotatably connected to the end frame 321.

[0066] See Figure 5 Inside the inner shell 31, an unwinding roller 311 and a take-up roller 312 are rotatably connected. The take-up roller 312 and the unwinding roller 311 are linked by a gear set; the direction of linkage ensures that they rotate synchronously, with one unwinding and the other rewinding. Inside the inner shell 31, a belt is also provided, with its two ends wrapped around the unwinding roller 311 and the take-up roller 312 respectively, and the belt passes over the coating member 322, with the material coating surface of the belt facing the side of the coating member 322 away from the inner shell 31.

[0067] The material on the belt can be correction tape or dotted adhesive. The bonding of the belt and its material can be achieved using existing technology, which will not be elaborated here. The pressing structure of this solution can be applied to inner core 3 for different needs, and inner core 3 can also be replaced according to actual requirements.

[0068] Based on the above implementation plan, see Figure 6 and Figure 8 The interior of half 11 is hollow, and a guide structure 7 and a limiting structure 8 are provided between half 11 and the pressing member 2.

[0069] The pressing member 2 is slidably connected to the half-part 11 via the guide structure 7. The guiding direction of the guide structure 7 is parallel to the sliding direction of the inner core 3. The guide structure includes a guide groove 71 and a guide block 72. The guide groove 71 is formed on the inner wall of the half-part 11, and the end of the guide groove 71 facing the pressing member 2 is an open end. The guide block is fixedly set on the outside of the pressing member 2.

[0070] See Figure 8 The limiting structure 8 can limit the sliding path of the pressing member 2. The limiting structure 8 includes a limiting slide 81 disposed inside half-11 and a limiting hook 82 disposed on the outer wall of the pressing member 2. The limiting hook 82 is a hook body with a certain degree of elasticity. During assembly, the guide block 72 is inserted into the guide groove 71. The end of the limiting hook 82 facing the inside of the outer shell 1 is inclined. Force is applied to the pressing member 2, causing the limiting hook 82 to deform slightly, and then it can be inserted into the limiting slide 81. Because the end face of the limiting hook 82 abuts against the inner wall of the limiting slide 81, the pressing member 2 will not separate from half-11.

[0071] Based on the above implementation plan, see Figures 7 to 9 The linkage component 4 includes a cylindrical linkage body 41, with a cylindrical cavity inside the linkage body 41. A first linkage part 42 and a second linkage part 43 are provided on the linkage body 41. The first linkage part 42 is located at the end of the linkage body 41 away from the inner core 3, and is a ring-shaped set of teeth with teeth arranged in a ring-shaped wave pattern, the ends of the teeth being pointed. A pressing groove 313 is provided at the end of the inner core 3 facing the linkage component 4, and the pressing groove 313 is a circular groove corresponding to the linkage body 41.

[0072] The second linkage part 43 is disposed on the periphery of the linkage body 41, and the second linkage part 43 is located near the inner core 3 of the linkage body 41; the second linkage part 43 includes several protrusions, the length direction of the protrusions is parallel to the sliding direction of the inner core 3, and the protrusions are evenly distributed in a circular array around the linkage body 41; the end of the protrusion away from the inner core 3 is provided with an inclined surface, and there are three protrusions.

[0073] The first mating structure 5 within half-section 11 includes a mating cylinder 51, which is a hollow cylinder fixedly installed inside half-section 11. A linkage body 41 can be inserted into the mating cylinder 51 and can rotate and slide within it. A sliding groove 52 is provided inside the mating cylinder 51. The sliding groove 52 is a through groove, and its through direction is parallel to the sliding direction of the inner core 3. The protrusion of the second linkage part 43 can be inserted into the sliding groove 52. The number of sliding grooves 52 corresponds to the number of protrusions. A positioning groove 53 is provided between two adjacent sliding grooves 52. The shape of the positioning groove 53 corresponds to the beveled end of the protrusion of the second linkage part 43, and the positioning groove 53 is located on the side facing the inner core 3.

[0074] See Figure 9 The pressing member 2 has a second mating structure 6 inside. The second mating structure 6 includes a cylindrical mating post 61. One end of the mating post 61 is fixedly connected to the inner wall of the pressing member 2, and the other end is set towards the linkage member 4. The linkage body 41 can be sleeved on the outside of the mating post 61, and the linkage body 41 can rotate and slide with the mating post 61. A pushing part 62 is provided on the outer side of the end of the mating post 61. The pushing part 62 is a toothed structure corresponding to the second linkage part 43.

[0075] When the pressing member 2 is pressed towards the inside of the outer casing 1, the pushing part 62 pushes the first linkage part 42. Due to the limiting effect of the toothed structure of the pushing part 62 and the first linkage part 42, the linkage part 4 does not rotate during the pressing process of the pressing member 2. As the linkage part 4 pushes the inner core 3, the protruding end of the second linkage part 43 moves into or out of the positioning groove 53, which can correspondingly change the position of the linkage part 4. If the protruding part of the second linkage part 43 is engaged in the positioning groove 53, the coating assembly 32 of the inner core 3 extends out of the outer casing 1. Conversely, if the protruding part enters the sliding groove 52, the inner core 3 retracts.

[0076] Based on the above implementation scheme, in order to ensure that the second linkage part 43 can rotate slightly relative to the position of the positioning groove 53 after the linkage part 4 is pressed, the angle of the pushing part 62 can be adjusted so that it applies a slight deflection force to the linkage part 4 when pressing.

[0077] Based on the above implementation plan, see Figure 7 A limiting block 44 is also provided on the outer wall of the linkage 4. The limiting block 44 is an arc-shaped block. When the linkage 44 is pressed and pushed a certain distance, the limiting block 44 can abut against the edge of the mating cylinder 51, thereby limiting the movement position of the linkage 44.

[0078] In the description of this application and its embodiments, it should be understood that the terms "top", "bottom", "height", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0079] In this application and its embodiments, unless otherwise expressly specified and limited, the terms "set," "install," "connect," "link," "fix," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0080] In this application and its embodiments, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0081] The foregoing disclosure provides many different embodiments or examples for implementing different structures of this application. To simplify the disclosure, specific examples of components and arrangements are described above. Of course, these are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this application, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0082] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0083] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A press-type coating tool characterized by, The application relates to a coating tool. The coating tool comprises a shell, an inner cavity, an external holding structure, a pressing piece, a linkage piece, an inner core, a coating assembly, a reset assembly, a winding roller, a take-up roller, a belt body and a guiding structure. The pressing piece is arranged at one end of the shell and is in sliding connection with the shell. The inner core is in sliding connection with the shell. The linkage piece is arranged in the shell and is in movable connection with the shell. The inner core comprises an inner shell, and a coating assembly is arranged at one end of the inner shell. The linkage piece is integrally formed, and the pressing piece and the shell are respectively provided with corresponding linkage pieces and fixed structures.

2. The press-type coating tool according to claim 1, wherein The pressing piece can drive the coating assembly of the inner core to extend or retract at the port of the shell through the linkage piece. The shell comprises a first half, a second half, a first cooperating structure, a second cooperating structure, a first fixed structure and a second fixed structure. The first half is in sliding connection with the pressing piece, the linkage piece is arranged in the first half, and the first half is provided with the first cooperating structure corresponding to the linkage piece.

3. The press-type coating tool according to claim 2, wherein The second half is internally provided with the inner core.

4. The press-type coating tool according to claim 2, wherein One end of the second half is connected with the first half, and the other end is provided with an open port for the coating assembly of the inner core to extend out. The first half and the second half are hinged on one side and are connected through a clamping structure on the other side.

5. The press-type coating tool according to claim 1, wherein The inner core further comprises a reset assembly arranged between the inner shell and the first half. The reset assembly can provide a reset force for the inner core to retract into the second half. The coating assembly comprises an end frame, a coating piece and a guiding structure.

6. The press-type coating tool according to claim 5, wherein The end frame is in detachable connection with the inner shell. The coating piece is in rotary connection with the end frame. The inner shell comprises a winding roller and a take-up roller. The winding roller and the take-up roller are in rotary connection with the inner shell.

7. The press-coating tool of claim 2, wherein The winding roller and the take-up roller are connected through a gear set. The belt body is wound around the winding roller and the take-up roller. The material of the belt body is coated on the coating piece.

8. The press-type coating tool according to claim 2, wherein The first half is internally provided with a cavity. The guiding structure is arranged between the first half and the pressing piece. The guiding direction of the guiding structure is parallel to the sliding direction of the inner core. The limiting structure can limit the sliding path of the pressing piece.

9. The press-coating tool of claim 8, wherein The linkage piece comprises a linkage main body, a first linkage part and a second linkage part. The linkage main body is internally provided with a cylindrical cavity. The first linkage part is arranged at one end of the linkage main body away from the inner core. The first linkage part is an annular tooth group.

10. The press-coating tool of claim 8, wherein The second linkage part is arranged on the circumferential side of the linkage main body. The second linkage part comprises a plurality of protrusions. The length direction of the protrusions is parallel to the sliding direction of the inner core. The protrusions are arranged in a circumferential array around the linkage main body. The end of the protrusion away from the inner core is provided with an inclined surface. The first cooperating structure comprises a cooperating cylinder and a sliding groove. The cooperating cylinder is a hollow cylinder arranged in the first half. The sliding groove is a through groove arranged in the cooperating cylinder. The guiding direction of the sliding groove is parallel to the sliding direction of the inner core. The second linkage part can be inserted into the sliding groove. The number of the sliding grooves corresponds to the number of the protrusions. The second cooperating structure is arranged in the pressing piece. The second cooperating structure comprises a second fixed structure. The cooperating column is a cylindrical body, one end of which is fixedly connected with the inner wall of the pressing member, and the other end is arranged towards the linkage member, and the linkage body can be sleeved outside the cooperating column; The pushing part is arranged outside the end of the cooperating column, and the pushing part is a toothed structure corresponding to the second linkage part.