Detachable expansion bolt capable of being repeatedly used

Abstract

The invention mainly relates to the technical field of fasteners, in particular to a detachable and reusable expansion bolt which comprises a fixed sleeve, a driving mechanism and a push rod are arranged in the fixed sleeve, the push rod is driven by the driving mechanism and can move in the axis direction of the fixed sleeve, and a plurality of conical guide surfaces which are arranged at equal intervals in the length direction of the push rod are arranged on the periphery of the push rod; expansion assemblies which are equal to the conical guide faces in number and correspond to the conical guide faces in position are further arranged in the fixed sleeve, each expansion assembly comprises a plurality of transmission rods evenly arranged in the circumferential direction of the push rod, and one end of each transmission rod extends into the containing groove from a radial guide hole in the inner wall of the fixed sleeve and is fixed to an expansion sliding block; the expansion sliding block is slidably installed in the containing groove, the containing groove penetrates to the outer surface of the fixing sleeve, the transmission rod is sleeved with a reset spring, one end of the reset spring is fixed to the inner end of the expansion sliding block, the other end of the reset spring is fixed to the groove bottom of the containing groove, and the reset spring is used for continuously pushing the other end of the transmission rod to make contact with the corresponding conical guide face all the time.

Description

Technical Field

[0001] This invention relates primarily to the field of fastener technology, and more specifically to a removable and reusable expansion bolt. Background Technology

[0002] Expansion bolts are among the most commonly used basic fasteners in construction engineering, equipment installation, and home decoration. They generate radial expansion force within a pre-drilled hole through an internal mechanical structure, thereby forming a firm connection with the substrate (such as concrete, brick walls, etc.). Traditional types of expansion bolts, such as wedge-type expansion bolts, typically rely on hammering or tightening to move the expansion tube or conical nut, forcing the expansion sleeve to open outward and lock it against the hole wall.

[0003] However, these traditional expansion bolts are designed for permanent or semi-permanent fastening. When they need to be removed (such as for equipment upgrades, layout adjustments, or repairs), the process is extremely difficult. They typically require forceful removal using hammering, prying, or other violent methods. This not only easily causes irreversible damage to the surrounding wall or substrate (such as enlarged holes, cracks, and chipping), but the bolt itself also undergoes plastic deformation or fracture, failing to maintain its original mechanical properties and structural integrity, thus making recycling impossible.

[0004] Therefore, the market urgently needs an expansion bolt solution that can provide stable and reliable fastening force after installation, and can be quickly and non-destructively disassembled and reused when needed. Summary of the Invention

[0005] 1. The technical problem that the invention aims to solve: This invention provides a removable and reusable expansion bolt to solve the technical problems existing in the background art.

[0006] 2. Technical Solution: To achieve the above objectives, the technical solution provided by the present invention is as follows: a detachable and reusable expansion bolt, comprising a fixed sleeve, wherein a driving mechanism is provided inside the fixed sleeve, and a push rod driven by the driving mechanism and movable along the axis of the fixed sleeve, wherein the outer periphery of the push rod is provided with a plurality of tapered guide surfaces arranged at equal intervals along its length direction; The fixed sleeve is further provided with an expansion assembly that is equal in number and position to the conical guide surfaces. The expansion assembly includes a plurality of transmission rods evenly arranged along the circumference of the push rod. One end of each transmission rod extends from a radial guide hole in the inner wall of the fixed sleeve into a receiving groove and is fixed to an expansion slider. The expansion slider is slidably installed in the receiving groove, which extends to the outer surface of the fixed sleeve. A return spring is sleeved on the transmission rod. One end of the return spring is fixed to the inner end of the expansion slider, and the other end is fixed to the bottom of the receiving groove, so as to continuously push the other end of the transmission rod to always keep in contact with the corresponding conical guide surface.

[0007] Furthermore, the outer surface of the expansion slider is an arc-shaped structure with the curvature of the outer wall of the fixed sleeve.

[0008] Furthermore, the arc surface of the expansion slider is provided with multiple friction protrusions.

[0009] Furthermore, each of the friction protrusions engages with a radially opened sliding hole on the arc surface of the expansion slider, and the inner end of the friction protrusion abuts against the elastic sheet, which is fixedly installed in the mounting cavity inside the expansion slider.

[0010] Furthermore, a deformation groove corresponding to the position of each sliding hole is provided on the side of the mounting cavity opposite to the sliding hole.

[0011] Furthermore, the driving mechanism includes a top cover threaded to the top end of the fixed sleeve and a bottom cover threaded to the bottom end. The top cover has a through hole, in which a driving screw is rotatably installed. The driving screw and the threaded hole at the top end of the push rod form a threaded pair. The bottom of the push rod has a guide groove, which slides in cooperation with a guide rod fixedly installed inside the bottom cover.

[0012] Furthermore, the top end of the drive screw extends above the top cover and is fixedly mounted with a rectangular drive block. A rectangular slot matching the shape of the rectangular drive block is opened at the center of a hexagonal drive head, and the rectangular drive block can be inserted into the rectangular slot to transmit torque.

[0013] Furthermore, the top of the push rod is provided with a tapered mating surface, and the taper direction of the tapered mating surface is the same as that of the tapered guide surface on the push rod.

[0014] Furthermore, the end of the transmission rod that contacts the tapered guide surface is machined into a spherical end.

[0015] Furthermore, the outer peripheral wall of the fixed sleeve is provided with multiple sets of anti-rotation raised lines along its axial direction.

[0016] 3. Beneficial effects: Compared with the prior art, the technical solution provided by this invention has the following advantages: During installation, holes matching the fixing sleeve are first drilled in the wall or base. After the sleeve is placed in the hole, the drive mechanism pushes the push rod to move axially, causing the transmission rod to slide along the conical guide surface. As the diameter of the conical surface increases, the transmission rod pushes the expansion slider outward from the container groove, pressing against the inner wall of the mounting hole to achieve anchoring. During disassembly, the drive mechanism drives the push rod to move in the opposite direction. Under the combined action of the conical guide surface and the return spring, the expansion slider retracts into the container groove, releasing the expansion state, and the fixing sleeve can be removed, achieving reuse and convenient disassembly. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the front cross-section structure of the present invention; Figure 3 This is a schematic diagram of the exploded structure of the present invention; Figure 4 This is a schematic diagram of the expansion component structure of the present invention; Figure 5 This is a schematic diagram of the cross-sectional structure of the expansion slider of the present invention; Figure 6 For the present invention Figure 3 Enlarged structural diagram at point A in the middle.

[0018] Figure label: 1. Fixed sleeve; 101. Radial guide hole; 102. Receiving groove; 103. Anti-rotation ridge; 2. Drive mechanism; 201. Top cover; 2011. Through hole; 202. Bottom cover; 203. Drive screw; 204. Guide rod; 3. Push rod; 301. Tapered guide surface; 302. Threaded hole; 303. Guide groove; 304. Tapered mating surface; 4. Expansion assembly; 401. Transmission rod; 402. Expansion slider; 4021. Sliding hole; 4022. Mounting cavity; 4023. Deformation groove; 403. Return spring; 404. Friction protrusion; 405. Elastic sheet; 5. Rectangular drive block; 6. Hexagonal drive head; 601. Rectangular slot. Detailed Implementation

[0019] To facilitate understanding of the present invention, a more complete description of the invention will be given below with reference to the accompanying drawings, which illustrate several embodiments of the invention. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the invention will be more thorough and complete.

[0020] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "page," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention 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. Therefore, they should not be construed as limitations on this invention.

[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0022] In this invention, unless otherwise explicitly specified and limited, the terms "installed," "connected," "linked," "fixed," and "equipped" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances. Example

[0023] See attached document Figure 1-6 A removable and reusable expansion bolt includes a fixed sleeve 1, a drive mechanism 2 inside the fixed sleeve 1, and a push rod 3 driven by the drive mechanism 2 and movable along the axis of the fixed sleeve 1. The outer periphery of the push rod 3 is provided with a plurality of tapered guide surfaces 301 arranged at equal intervals along its length. The fixed sleeve 1 is also provided with an expansion assembly 4, which is equal in number and position to the conical guide surface 301. The expansion assembly 4 includes a plurality of transmission rods 401 evenly arranged around the push rod 3. One end of each transmission rod 401 extends from the radial guide hole 101 on the inner wall of the fixed sleeve 1 into the receiving groove 102 and is fixed to an expansion slider 402. The expansion slider 402 is slidably installed in the receiving groove 102, which extends to the outer surface of the fixed sleeve 1. A return spring 403 is sleeved on the transmission rod 401. One end of the return spring 403 is fixed to the inner end of the expansion slider 402, and the other end is fixed to the bottom of the receiving groove 102, so as to continuously push the other end of the transmission rod 401 to always keep in contact with the corresponding conical guide surface 301.

[0024] In this embodiment, after drilling an installation hole matching the fixing sleeve 1 in the wall or base, the fixing sleeve 1 is placed into the hole. The drive mechanism 2 pushes the push rod 3 to move along its axial direction, causing the transmission rod 401 to slide along the tapered guide surface 301. As the diameter of the tapered surface gradually increases, the transmission rod 401 is pushed by the thrust to drive the expansion slider 402 to extend outward from the receiving groove 102, and finally presses tightly against the inner wall of the installation hole to achieve anchoring. When disassembling, the drive mechanism 2 drives the push rod 3 to move in the opposite direction. Under the cooperation between the tapered guide surface 301 and the transmission rod 401 and the elastic restoring force of the return spring 403, the expansion slider 402 retracts into the receiving groove 102, releasing the expansion state, and the fixing sleeve 1 can be taken out from the hole, realizing reuse and convenient disassembly.

[0025] The outer surface of the expansion slider 402 is an arc-shaped structure with the same curvature as the outer wall of the fixed sleeve 1, which is used to increase the contact area with the inner wall of the mounting hole and improve the anchoring stability.

[0026] The expansion slider 402 has multiple friction protrusions 404 on its arc surface to enhance the friction between it and the inner wall of the mounting hole, thereby further improving the anchoring effect.

[0027] Each friction protrusion 404 is engaged with a sliding hole 4021 radially opened on the arc surface of the expansion slider 402. The inner end of the friction protrusion 404 abuts against the elastic sheet 405, and the elastic sheet 405 is fixedly installed in the mounting cavity 4022 inside the expansion slider 402.

[0028] In this embodiment, the elastic deformation of the elastic sheet 405 allows each friction protrusion 404 to extend and retract independently to adapt to the unevenness of the hole wall contour, thereby achieving a fit.

[0029] On the side of the mounting cavity 4022 away from the sliding hole 4021, there is a deformation groove 4023 corresponding to the position of each sliding hole 4021.

[0030] In this embodiment, when the friction protrusion 404 is pressed, the elastic sheet 405 is pushed into the deformation groove 4023 to provide a larger deformation space and expand the adaptive adjustment range.

[0031] The drive mechanism 2 includes a top cover 201 threaded to the top of the fixed sleeve 1 and a bottom cover 202 threaded to the bottom. The top cover 201 has a through hole 2011, in which a drive screw 203 is rotatably installed. The drive screw 203 and the threaded hole 302 at the top of the push rod 3 form a threaded pair. The bottom of the push rod 3 has a guide groove 303, which slides in cooperation with a guide rod 204 fixedly installed inside the bottom cover 202.

[0032] In this embodiment, by rotating the drive screw 203, the threaded transmission between the screw and the threaded hole 302, and in conjunction with the sliding constraint between the guide rod 204 and the guide groove 303, the push rod 3 is driven to move along the axial direction of the fixed sleeve 1.

[0033] The top end of the drive screw 203 extends above the top cover 201 and is fixedly mounted with a rectangular drive block 5. A rectangular slot 601 matching the shape of the rectangular drive block 5 is opened in the center of a hexagonal drive head 6. The rectangular drive block 5 can be inserted into the rectangular slot 601 to transmit torque.

[0034] In this embodiment, when the hexagonal drive head 6 is engaged with the rectangular drive block 5, the hexagonal drive head 6 can be rotated with a tool to drive the drive screw 203 to rotate; after removing the hexagonal drive head 6 and unscrewing the top cover 201, the drive screw 203 and the push rod 3 connected to it can be taken out of the fixed sleeve 1 as a whole for easy maintenance and replacement.

[0035] The top of the push rod 3 is provided with a tapered mating surface 304, and the taper direction of the tapered mating surface 304 is the same as that of the tapered guide surface 301 on the push rod 3.

[0036] In this embodiment, in the disassembled state, the reset spring 403 pushes the transmission rod 401 and the expansion slider 402 to return to their maximum stroke. When the push rod 3 is installed from the bottom of the fixed sleeve 1, the tapered mating surface 304 at its top can guide the end of the transmission rod 401 to slide, so that the push rod 3 and the drive screw 203 can be smoothly installed back into place.

[0037] The end of the transmission rod 401 that contacts the tapered guide surface 301 is machined into a spherical end to reduce contact friction and make the transmission process smoother.

[0038] The outer peripheral wall of the fixed sleeve 1 is provided with multiple sets of anti-rotation ridges 103 along its axial direction, which are used to increase the circumferential frictional resistance in the mounting hole and prevent the fixed sleeve 1 from rotating when the drive screw 203 is screwed.

[0039] The above-described embodiments are merely illustrative of certain implementations of the present invention, and are described in a relatively specific and detailed manner. However, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements are all within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

[0040] It should be noted that the above content falls within the scope of the inventor's technical knowledge. Due to the vast and complex nature of the technical content in this field, the above content of this application does not necessarily constitute prior art.

Claims

1. A reusable expansion bolt, characterized in that: It includes a fixed sleeve (1), a drive mechanism (2) is provided inside the fixed sleeve (1), and a push rod (3) driven by the drive mechanism (2) and movable along the axis of the fixed sleeve (1). The outer periphery of the push rod (3) is provided with a plurality of tapered guide surfaces (301) arranged at equal intervals along its length direction. The fixed sleeve (1) is also provided with an expansion assembly (4) that is equal in number and position to the conical guide surface (301). The expansion assembly (4) includes a plurality of transmission rods (401) evenly arranged around the push rod (3). One end of each transmission rod (401) extends from the radial guide hole (101) on the inner wall of the fixed sleeve (1) into the receiving groove (102) and is fixed to an expansion slider (402). The expansion slider (402) is slidably installed in the receiving groove (102). The receiving groove (102) extends to the outer surface of the fixed sleeve (1). A return spring (403) is sleeved on the transmission rod (401). One end of the return spring (403) is fixed to the inner end of the expansion slider (402), and the other end is fixed to the bottom of the receiving groove (102). It is used to continuously push the other end of the transmission rod (401) to always keep in contact with the corresponding conical guide surface (301).

2. The reusable expansion bolt according to claim 1, characterized in that: The outer surface of the expansion slider (402) is an arc surface structure with the same curvature as the outer wall of the fixed sleeve (1).

3. The reusable expansion bolt according to claim 2, characterized in that: The expansion slider (402) has multiple friction protrusions (404) on its arc surface.

4. The reusable expansion bolt according to claim 3, characterized in that: Each of the friction protrusions (404) is engaged with the sliding hole (4021) radially opened on the arc surface of the expansion slider (402). The inner end of the friction protrusion (404) abuts against the elastic sheet (405), and the elastic sheet (405) is fixedly installed in the mounting cavity (4022) inside the expansion slider (402).

5. The reusable expansion bolt according to claim 4, characterized in that: A deformation groove (4023) corresponding to the position of each sliding hole (4021) is provided on the side of the mounting cavity (4022) away from the sliding hole (4021).

6. The reusable expansion bolt according to claim 1, characterized in that: The driving mechanism (2) includes a top cover (201) threaded to the top of the fixed sleeve (1) and a bottom cover (202) threaded to the bottom. The top cover (201) has a through hole (2011) and a driving screw (203) is rotatably installed in the through hole (2011). The driving screw (203) and the threaded hole (302) at the top of the push rod (3) form a threaded pair. The bottom of the push rod (3) has a guide groove (303) and the guide groove (303) slides with the guide rod (204) fixedly installed inside the bottom cover (202).

7. The reusable expansion bolt according to claim 6, characterized in that: The top end of the drive screw (203) extends above the top cover (201) and is fixedly mounted with a rectangular drive block (5). A rectangular slot (601) matching the shape of the rectangular drive block (5) is opened in the center of a hexagonal drive head (6). The rectangular drive block (5) can be inserted into the rectangular slot (601) to transmit torque.

8. The reusable expansion bolt according to claim 1, characterized in that: The top of the push rod (3) is provided with a tapered mating surface (304), and the taper direction of the tapered mating surface (304) is the same as that of the tapered guide surface (301) on the push rod (3).

9. The reusable expansion bolt according to claim 1, characterized in that: The end of the transmission rod (401) that contacts the tapered guide surface (301) is machined into a spherical end.

10. A reusable expansion bolt according to claim 1, characterized in that: The outer peripheral wall of the fixed sleeve (1) is provided with multiple sets of anti-rotation ridges (103) along its axial direction.

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