Fastener, expansion screw, and expansion nut

Abstract

A fastener, comprising an insert (11) and an expansion member (12). The insert comprises a first end and a second end; first sawtooth surfaces (14) are provided on two opposite side surfaces of the first end and the second end; the second end is connected to the top of the expansion member by means of a breakable connecting member (13); the expansion member is provided with an accommodating space; the expansion member forms breaking surfaces (121) on two sides of the accommodating space; second sawtooth surfaces (141) are provided on the surfaces of the breaking surfaces; and when the insert enters the accommodating space, the expansion member expands outwards, and the first sawtooth surfaces are engaged with the second sawtooth surfaces. The present invention further provides an expansion screw and an expansion nut both comprising the fastener, and furniture.

Description

Fasteners and expansion screws and expansion nuts Technical Field

[0001] The present application relates to the field of fasteners, and in particular to a fastener and an expansion screw and an expansion nut comprising the fastener, as well as furniture. Background Art

[0002] Fasteners are very common in daily life, especially in the installation and connection of panel furniture. Fasteners include screws, nuts, or bolts. In order to make the connection between the fasteners and the panels more secure, fastener assemblies with expansion structures have appeared on the market, such as expansion bolts, expansion nuts, and expansion screws. This fastener assembly usually has an expansion tube outside the screw or nut. When the screw or nut is installed into the panel, the expansion tube is squeezed outward and expands, thereby increasing the bite force between the screw or nut and the panel. However, this fastener assembly has the problem of insufficient bite force after being driven into the panel to be connected, and the fixation is not firm. Therefore, it is necessary to develop a new fastener assembly.

[0003] Summary of the Invention

[0004] The purpose of the embodiments of the present application is to provide a fastener and an expansion screw and an expansion nut with the fastener, as well as furniture.

[0005] An embodiment of the present application is implemented as follows: a fastener includes an insert and an expansion member, wherein the insert includes a first end and a second end, and two opposite side surfaces between the first end and the second end are provided with a first serrated surface; the second end is connected to the top of the expansion member through a breakable connecting member, and the expansion member is provided with a accommodating space for accommodating the insert, and the expansion member forms a cross-section on both sides of the accommodating space corresponding to the first serrated surface of the insert, and the surface of the cross-section is provided with a second serrated surface. When the insert enters the accommodating space, the expansion member expands outward, and the first serrated surface and the second serrated surface engage with each other.

[0006] Furthermore, the side surfaces of the insert that are away from each other are respectively provided with the first serrated surfaces.

[0007] Furthermore, the expansion piece is annular as a whole, and includes four sections.

[0008] Furthermore, the number of the breakable connecting parts is the same as the number of the cross sections.

[0009] Furthermore, the breakable connecting piece is a rod-shaped object.

[0010] Furthermore, the outer side surface of the expansion member is a serrated surface.

[0011] Furthermore, the end surface of the first end is a plane, and the cross section of the second end is an inverted trapezoid.

[0012] Furthermore, the present application also provides an expansion nut, comprising the above-mentioned fastener and a nut body, one end of which is connected to the fastener.

[0013] Furthermore, the nut body is a cylindrical structure, and the inner surface of the nut body is provided with threads.

[0014] Furthermore, the expansion nut also includes a snap-fit ​​structure, which is arranged on the inner surface of the nut body.

[0015] Furthermore, the opening of the buckle structure faces the center of the nut body.

[0016] Furthermore, the nut body is a double-cylindrical structure, and the inner surface of each cylinder is provided with a snap-fit ​​structure.

[0017] Furthermore, the outer surface of the nut body is provided with a serrated surface.

[0018] Furthermore, the expansion nut is integrally formed.

[0019] Furthermore, the present application also provides an expansion screw, comprising the above-mentioned fastener, and also comprising a screw body and a screw head, wherein the fastener is arranged at one end of the screw body, and the screw head is arranged at the other end of the screw body.

[0020] Furthermore, the screw head includes a connecting section, a clamping section and a head, the connecting section, the clamping section and the head are connected in sequence, and the connecting section is connected to the screw body.

[0021] Furthermore, the cross-sections of the connecting section and the engaging section are circular, and the cross-section diameter of the engaging section is smaller than that of the connecting section.

[0022] Furthermore, the screw body is an openable shell-like structure.

[0023] Furthermore, a limiting protrusion is provided on the inner surface of the screw body, and the screw head further comprises a limiting section, the diameter of the limiting section being larger than the inner diameter of the limiting protrusion.

[0024] Furthermore, the limiting section is located at the end of the screw head close to the screw body.

[0025] Furthermore, a spring is installed inside the screw body, and the spring is arranged axially along the screw body.

[0026] Furthermore, one end of the spring abuts against the screw head.

[0027] Furthermore, the expansion screw is integrally formed.

[0028] Furthermore, the present application also provides a piece of furniture, comprising the above-mentioned expansion nut or expansion screw, wherein the expansion nut and expansion screw are used for connection.

[0029] Furthermore, the furniture is a cabinet or a table.

[0030] This application has the following beneficial effects: The fastener provided herein has a simple structure and activation method, is easy to use, and can be added as an additional component or integrally formed with other fasteners, such as nuts and screws, to form a fastener assembly. For example, by attaching a fastener to one end of a conventional expansion nut, the engagement between the expansion nut and the connected object becomes more secure, making it less likely to loosen or fall off. By attaching the fastener assembly to other connected objects, the connections between the connected objects can be further tightened. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] FIG1 is a schematic structural diagram of a fastener provided in a first embodiment of the present application;

[0032] FIG2 is a perspective view of a fastener provided in a second embodiment of the present application;

[0033] FIG3 is a perspective view of an expansion nut provided in a third embodiment of the present application;

[0034] FIG4 is a front view of an expansion nut provided in a third embodiment of the present application;

[0035] FIG5 is a top view of an expansion nut provided in a third embodiment of the present application;

[0036] FIG6 is a bottom view of an expansion nut provided in a third embodiment of the present application;

[0037] FIG7 is a cross-sectional view taken along line AA in FIG4 ;

[0038] FIG8 is a front view of an expansion screw provided in a fourth embodiment of the present application;

[0039] FIG9 is a perspective view of an expansion screw provided in a fourth embodiment of the present application;

[0040] FIG10 is a schematic structural diagram of a retractable expansion screw provided in a fifth embodiment of the present application;

[0041] FIG11 is a schematic diagram of the assembly of the expansion screw and expansion nut provided in this application;

[0042] FIG12 is a schematic cross-sectional view of FIG11 . DETAILED DESCRIPTION

[0043] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, this application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0044] The first embodiment of the present application provides a fastener that is integrally formed (e.g., by injection molding) and can be arranged at the end of other fasteners (e.g., screws and nuts) to form a fastener assembly for increasing the bite force between the fastener assembly and a wall or connecting plate. As shown in FIG1 , the fastener includes an insert 11 and an expansion member 12, wherein the insert 11 includes a first end for contacting the surface of the object to be connected and a second end for entering the expansion member, and two opposing side surfaces between the first end and the second end are provided with a first serrated surface 14. The second end is connected to the top of the expansion member 12 via a breakable connector 13, and the expansion member 12 is provided with a receiving space for accommodating the insert 11. In the receiving space, the expansion member 12 forms a cross-section 121 opposite to the first serrated surface 14 of the insert 11 on both sides, and the surface of the cross-section 121 is provided with a second serrated surface 141. When the insert 11 enters the receiving space, the expansion member 12 expands outward, and the first serrated surface 14 and the second serrated surface 141 engage with each other. This arrangement makes it easy for the insert 11 to enter the accommodating space, but difficult to pull out. For example, it can be arranged so that the first serrated surface 14 and the second serrated surface 141 have serration directions opposite to each other.

[0045] As shown in Figure 1, insert 11 is a single piece, with a flat first end surface, allowing it to rest against the end surface of the object to be connected during installation. Continued application of pressure can break breakable connector 13. The second end cross-section of insert 11 is an inverted trapezoid or inverted cone, which makes it easier for insert 11 to enter the accommodating space when pressure is applied.

[0046] Furthermore, portions of the two opposite side surfaces of the insert 11 corresponding to the cross section 121 are respectively provided with serrated surfaces 14 . The serrated surfaces 14 may cover the entire side surface or may be arranged only at positions corresponding to the cross section 121 .

[0047] A storage space is provided in the middle of the expansion member 12, with sections 121 on both sides of the storage space. In this embodiment, the expansion member 12 is annular as a whole, and four sections 121 are formed in the middle. The surface of each section 121 is provided with a second serrated surface 141. The direction of the second serrated surface 141 on the surface of the section 121 is opposite to the direction of the first serrated surface 14 on the surface of the insert 11, so that the insert 11 can easily enter the storage space but is difficult to pull out. The second end of the insert 11 is connected to the top of the expansion member 12 via a breakable connector 13. Specifically, one end of the breakable connector 13 is connected to the bottom of the first serrated surface 14 of the insert 11, and the other end is connected to the top surface of the expansion member 12 or the upper end of the section 121. This allows the insert 11 to be located above the storage space. After the breakable connector 13 is broken, it can enter the expansion member 12 along the storage space, squeeze the expansion member 12, and cause the expansion member 12 to expand outward.

[0048] Furthermore, the outer side surface of the expansion member 12 is configured as a serrated surface, so that the bite force between the expansion member 12 and the wall or the connecting plate is stronger after the expansion member 12 expands outwards.

[0049] Furthermore, the minimum width of the cross section of the insert 11 at the position corresponding to the section 121 needs to be greater than the minimum width of the cross section of the accommodation space of the expansion member 12, so that the expansion member can expand outward after the insert 11 enters the accommodation space.

[0050] The breakable connector 13 is a rod-shaped object, specifically a short rod, with the same number of sections as the cross-sections 121 and located at positions corresponding to the cross-sections 121. It breaks when subjected to a compressive force. Using multiple short rods as connectors allows for a multi-point connection between the insert 11 and the expansion member 12. This allows the short rods to break without much external force, making the fastener easier to trigger.

[0051] When in use, the fastener assembly with the fastener is placed in a preset hole in the object to be connected, and the insert 11 is pushed into the hole with the head facing inward. When the end of the insert 11 rests against the end of the hole, the thrust is continued to be applied. At this time, the breakable connecting part 13 is broken, and the insert 11 is pressed into the cross-section of the expansion part 12. The serrated surfaces of the two engage, causing the expansion part 12 to expand outward, thereby increasing the bite force between the fastener assembly and the wall or other panels.

[0052] As shown in FIG2 , a second embodiment of the present application provides a fastener comprising an integral insert 10 with a serrated surface extending across its entire side. An expansion member 12 is generally circular, with a central portion cut to form two sections 121, each section 121 having a serrated surface. The top of each section 121 is connected to the integral insert 10 via a breakable connector 13.

[0053] As shown in Figures 3-7, the third embodiment of the present application provides an expansion nut, which can be used in conjunction with ordinary screws or expansion screws. The end of the expansion nut is provided with the fastener provided by the first embodiment, and also includes a nut body 21 and a snap-fit ​​structure 22, wherein the fastener is provided at one end of the nut body 21, and the inner side surface of the nut body 21 is provided with the snap-fit ​​structure 22, and the opening of the snap-fit ​​structure 22 faces the center of the nut body 21. In this embodiment, the nut body 21 is connected to the screw through the snap-fit ​​structure 22. In other embodiments, the nut body 21 can be a cylindrical structure with a threaded inner surface, and is connected to the screw or bolt through a thread (not shown in the figure).

[0054] As shown in Figures 3 and 4, the nut body 21 is a double-cylindrical structure with a cross-sectional shape of two intersecting circles. The cross-section 121 of the fastener (in Figure 1) is located above the intersection of the two circles. The outer side of the nut body 21 is provided with a serrated surface for increasing the bite force.

[0055] Furthermore, as shown in Figures 5-7, the inner wall of each cylinder of the nut body 21 (in Figure 3) is provided with a snap-fit ​​structure 22, which is used to accommodate and secure a screw. The opening of the snap-fit ​​structure 22 is oriented toward the center of the nut body 21, making it easy for the screw to enter the snap-fit ​​structure 22 but difficult to remove.

[0056] Furthermore, the nut body 21 is configured as a double-cylinder structure, so that after the screw is inserted into the nut body 21, it can be selected to be engaged with the snap structure on the left or the snap structure on the right as needed, thereby increasing the scope of application of the expansion nut.

[0057] Furthermore, the expansion nut is integrally formed, for example, by injection molding.

[0058] When in use, place the expansion nut with the fastener into the preset hole of the object to be connected, push the insert 11 into the hole with the head facing inward, and when the end of the insert 11 rests against the end of the hole, continue to apply thrust. At this time, the breakable connecting part 13 is pressed off, and the insert 11 enters the cross-section of the expansion part 12. The serrated surfaces of the two engage, causing the expansion part 12 to expand outward, increasing the bite force between the fastener assembly and the wall or other panels.

[0059] The fourth embodiment of the present application provides an expansion screw that can be used with both ordinary nuts and expansion nuts. As shown in Figures 8 and 9, the expansion screw includes the fastener described in the second embodiment, and also includes a screw body 31 and a screw head 32, wherein the fastener is provided at one end of the screw body 31 and the screw head 32 is provided at the other end of the screw body 31. The screw head 32 includes a connecting section 321, a locking section 322, and a head 323. The connecting section 321, the locking section 322, and the head 323 are connected in sequence, and the connecting section 321 is connected to the screw body 31.

[0060] Furthermore, the screw body 31 is a cylindrical structure, and a serrated surface is provided on the side surface for increasing the bite force. The screw head 32 is fixedly connected to one end of the screw body 31.

[0061] Furthermore, the connecting section 321 and the locking section 322 of the screw head 32 are cylindrical in shape and circular in cross section. The cross-sectional diameter of the locking section 322 is smaller than that of the connecting section 321, so that the locking section 322 can be locked into the locking structure of the nut, such as the locking structure 22 in the expansion nut provided in the third embodiment.

[0062] Furthermore, the head 3323 of the screw head 32 is hemispherical, and the plane of the head 323 is connected to the engaging section 322. The head 323 is arranged in an arc shape so that the head can be more easily inserted into the nut.

[0063] When in use, push the expansion screw into the preset hole of the object to be connected (the specific steps are the same as above) to achieve a fastening connection between the expansion screw and the object to be connected. The expansion screw can be connected to the nut on the other object to be connected to achieve the connection between the two objects to be connected.

[0064] Furthermore, the expansion screw is integrally formed, for example, by injection molding.

[0065] The fifth embodiment of the present application provides a retractable expansion screw, as shown in Figure 10. This expansion screw differs from the expansion screw provided in the fourth embodiment of the present application in that the screw body of this expansion screw is an openable shell-like structure, with a spring disposed within the shell. The screw head is connected to the spring, enabling the screw head to retract. A transition section may or may not be provided between the screw housing 311 and the fastener. The transition section is a section of the screw body 31 in the fourth embodiment.

[0066] Specifically, the screw housing 311 of the expansion screw is divided into two parts, connected by a connecting structure comprising a connecting column 312 and a connecting hole 313, respectively provided on the contact surfaces of the two parts. In other embodiments, the connecting structure may be in other forms, such as a snap-fit ​​connection. Limiting protrusions 314 are provided at the top and bottom ends of the screw housing 311 to retain the screw head and prevent excessive movement.

[0067] Furthermore, the screw head of the retractable expansion screw includes, in addition to the connecting section 321, the engaging section 322, and the head 323, a limiting section 324. The limiting section 324 is connected to the connecting section 321. The limiting section 324 has a larger diameter than the limiting protrusion 314, preventing the screw head from falling out of the screw housing 311. The connecting section 321 has a smaller diameter than the limiting protrusion 314, allowing the screw head to retract into the housing when the head 323 is subjected to a compressive force.

[0068] Furthermore, a spring 33 is provided inside the screw housing 311 , one end of the spring 33 abuts against the top surface of the fastener (or transition section), and the other end abuts against the limiting section 324 .

[0069] This retractable expansion screw is suitable for seamless installations that require concealed fasteners. This method is commonly used in the installation of furniture made of panels, such as wardrobes, bookcases, or tables. To use, the expansion screw is connected to one panel with the screw head facing outward. The screw head is then pressed into the screw housing and aligned with the connection hole of the other panel to be connected. The screw head is then released, and it springs back into the connection hole, completing the seamless connection between the two panels.

[0070] Figures 11 and 12 are schematic diagrams and cross-sectional views of the expansion screw (fifth embodiment) and expansion nut (third embodiment) provided by this application after connection. As shown in Figure 12, the locking section 322 of the expansion screw is located within the buckle structure 22 of the expansion nut.

[0071] When in use, connect the expansion screw to one object to be connected, connect the expansion nut to another object to be connected, and then connect the expansion screw and the expansion nut as shown in the figure.

[0072] Furthermore, the present application also provides a piece of furniture comprising one or more of the above-mentioned fasteners, expansion screws and expansion nuts.

[0073] Furthermore, the furniture may be a cabinet, a chair, a table, or the like.

[0074] This application has the following beneficial effects: The fastener provided herein has a simple structure and activation method, is easy to use, and can be added as an additional component or integrally formed onto other fasteners to form a fastener assembly. By attaching the fastener to one end of a conventional expansion nut, the engagement between the expansion nut and the connected item becomes more secure, making it less likely to loosen or fall off. By attaching expansion bolts with the fastener to the remaining connected items, the connections between the items can be further tightened.

[0075] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the principles of the present application should be included in the scope of protection of the present application.

Claims

1. A fastener, characterized in that: It comprises an embedding piece and an expansion piece, wherein the embedding piece comprises a first end and a second end, and two opposite side surfaces between the first end and the second end are provided with a first serrated surface; the second end is connected to the top of the expansion piece through a breakable connecting piece, and the expansion piece is provided with a accommodating space for accommodating the embedding piece, and the expansion piece forms a section on both sides of the accommodating space corresponding to the first serrated surface of the embedding piece, and the surface of the section is provided with a second serrated surface, and when the embedding piece enters the accommodating space, the expansion piece expands outward, and the first serrated surface and the second serrated surface are meshed with each other.

2. The fastener according to claim 1, characterized in that The side surfaces of the insert that are away from each other are respectively provided with the first serrated surfaces.

3. The fastener according to claim 2, characterized in that The expansion piece is annular as a whole and includes four sections.

4. The fastener according to any one of claims 1 to 3, characterized in that: The number of the breakable connecting pieces is the same as the number of the cross sections.

5. The fastener according to any one of claims 4, characterized in that: The breakable connecting piece is a rod-shaped object.

6. The fastener according to any one of claims 1 to 3, characterized in that: The outer side surface of the expansion piece is a serrated surface.

7. The fastener according to any one of claims 1 to 3, characterized in that: The end surface of the first end is a plane, and the cross-sectional shape of the second end is an inverted trapezoid.

8. An expansion nut, comprising the fastener according to any one of claims 1 to 7, characterized in that: It also includes a nut body, one end of which is connected to the fastener.

9. The expansion nut according to claim 8, characterized in that: The nut body is a cylindrical structure, and the inner surface of the nut body is provided with threads.

10. The expansion nut according to claim 8, characterized in that: It also includes a buckle structure, which is arranged on the inner surface of the nut body.

11. The expansion nut according to claim 10, characterized in that: The opening of the buckle structure faces the center of the nut body.

12. The expansion nut according to claim 11, characterized in that: The nut body is a double-cylindrical structure, and a buckle structure is arranged on the inner surface of each cylinder.

13. The expansion nut according to any one of claims 8 to 12, characterized in that: The outer surface of the nut body is provided with a serrated surface.

14. The expansion nut according to any one of claims 8 to 12, characterized in that: The expansion nut is integrally formed.

15. An expansion screw, comprising the fastener according to any one of claims 1 to 7, characterized in that: It also includes a screw body and a screw head, wherein the fastener is arranged at one end of the screw body, and the screw head is arranged at the other end of the screw body.

16. The expansion screw according to claim 15, characterized in that: The screw head comprises a connecting section, a clamping section and a head, wherein the connecting section, the clamping section and the head are connected in sequence, and the connecting section is connected to the screw body.

17. The expansion screw according to claim 16, characterized in that: The cross sections of the connecting section and the engaging section are circular, and the cross section diameter of the engaging section is smaller than that of the connecting section.

18. The expansion screw according to claim 15, characterized in that: The screw body is an openable shell-like structure.

19. The expansion screw according to claim 18, characterized in that: A limiting protrusion is arranged on the inner surface of the screw body, and the screw head further comprises a limiting section, the diameter of which is larger than the inner diameter of the limiting protrusion.

20. The expansion screw according to claim 19, characterized in that: The limiting section is located at the end of the screw head close to the screw body.

21. The expansion screw according to any one of claims 18 to 20, characterized in that: A spring is arranged inside the screw body, and the spring is arranged axially along the screw body.

22. The expansion screw according to claim 21, characterized in that: One end of the spring abuts against the screw head.

23. The expansion screw according to any one of claims 15 to 20, characterized in that: The expansion screw is integrally formed.

24. A piece of furniture, characterized in that: It comprises the expansion nut according to any one of claims 8 to 14 or the expansion screw according to any one of claims 15 to 23, wherein the expansion nut and the expansion screw are used for connection.

25. The piece of furniture according to claim 24, characterized in that The furniture is a cabinet or a table.

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