A type of torque-limiting fastening screw
By designing a torque-limiting fastening screw, the threaded tube fracture mechanism is used to prevent the screw from over-tightening, thus solving the problem of over-tightening of the fastening screw when screwing into the base, achieving stable connection of the screw hole and convenient disassembly.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- JIAXING AOZHAN IND CO LTD
- Filing Date
- 2025-09-02
- Publication Date
- 2026-06-30
AI Technical Summary
Existing fastening screws are prone to over-tightening when screwed into the base, which can damage the screw hole and cause it to lose its gripping force.
Design a torque-limiting fastening screw by setting a threaded tube and a connecting post between the nut body and the screw body. The threaded tube's fracture mechanism prevents over-tightening, and the nut body design facilitates tool connection and unloading.
It effectively prevents screws from over-tightening, protects the engagement force of the screw holes, ensures stable screw connection, and facilitates disassembly.
Smart Images
Figure CN224433072U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of fastener technology, and in particular to a torque-limiting fastening screw. Background Technology
[0002] Fastening screws are fasteners that can be screwed into substrates such as wood and plastic. Existing fastening screws, such as self-tapping screws, often over-tighten when screwed into the substrate using an electric screwdriver. When the fastening screw is over-rotated, it damages the screw hole and slips in the screw hole, resulting in a loss of engagement between the fastening screw and the screw hole. Utility Model Content
[0003] To address the shortcomings of existing fastening screws that are prone to over-tightening and damaging the screw's engagement force, this invention proposes a torque-limiting fastening screw to prevent over-tightening from damaging the screw's engagement force.
[0004] To achieve the above objectives, the present invention adopts the following technical solution:
[0005] A torque-limiting fastening screw includes a screw body and a nut body. The screw body includes a stud and a screw head fixedly connected to the upper end of the stud. The outer diameter of the screw head is larger than the outer diameter of the stud. A groove is provided on the upper side of the screw head, and a downwardly extending threaded hole is provided at the bottom of the groove. The nut body includes a threaded tube, a connecting post, and a nut body. The threaded tube is threadedly connected to the threaded hole. The outer diameter of the connecting post is larger than the outer diameter of the threaded tube and is fixedly connected to the upper end of the threaded tube. The nut body is fixedly connected to the upper end of the connecting post for connecting a driving tool.
[0006] With the above setup, the drive tool drives the screw body through the cap. If the torque is too high, the thread tube will break, preventing the screw body from over-rotating and damaging the engagement force of the screw hole.
[0007] Furthermore, a cross groove is provided on the upper side of the cap.
[0008] The above settings facilitate the connection of the screwdriver to the cap.
[0009] Furthermore, the outer circumference of the cap is a hexagonal prism.
[0010] The above settings facilitate the connection of the wrench to the cap.
[0011] Furthermore, the cap body is provided with a downward-opening receiving groove, in which the screw head is placed, and the cap body encloses the screw head.
[0012] The above settings improve the stability of the cap on the screw head.
[0013] Furthermore, the lower side of the connecting column abuts against the bottom of the groove.
[0014] Furthermore, the groove is in the shape of a regular hexagon.
[0015] The above settings facilitate the removal of the screw body. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of the fastening screw used in an embodiment.
[0017] Figure 2 This is an exploded view of the fastening screw used in the embodiment.
[0018] Figure 3 This is a cross-sectional view of the fastening screw used in an embodiment.
[0019] Figure 4 This is a schematic diagram of the nut body in an embodiment.
[0020] Figure 5 This is a schematic diagram of the screw body being screwed onto the base in an embodiment. Detailed Implementation
[0021] The technical solution of this utility model will be further described in detail below through embodiments and in conjunction with the accompanying drawings.
[0022] like Figures 1 to 5 A torque-limiting fastening screw includes a screw body 3 and a nut body 4. The screw body 3 includes a stud 31 and a screw head 32 fixedly connected to the upper end of the stud 31. The outer diameter of the screw head 32 is larger than the outer diameter of the stud 31. A groove 33 is provided on the upper side of the screw head 32. A downwardly extending screw hole 34 is provided at the bottom of the groove 33. The nut body 4 includes a threaded tube 41, a connecting post 42 and a nut body 43. The threaded tube 41 is threadedly connected to the screw hole 34. The outer diameter of the connecting post 42 is larger than the outer diameter of the threaded tube 41 and is fixedly connected to the upper end of the threaded tube 41. The nut body 43 is fixedly connected to the upper end of the connecting post 42 and is used to connect a driving tool.
[0023] With the above settings, the driving tool drives the screw body 3 through the cap 43. When the torque is too large, the thread tube 41 breaks, preventing the screw body 3 from being over-rotated and damaging the engagement force of the screw hole 34.
[0024] The screw body 3 of this application is integrally formed. The stud 31 has an external thread on its outer circumference. The screw head 32 is a cylindrical structure and is coaxially fixed to the upper end of the stud 31. A groove 33 is provided on the upper side of the screw head 32. A screw hole 34 is provided at the bottom of the groove 33. The screw hole 34 extends downward into the stud 31. The thread direction of the screw hole 34 is consistent with the thread direction of the external screw hole 34 of the stud 31. The nut body 4 is integrally formed. The threaded tube 41 is screwed into the screw hole 34. The connecting post 42 is located in the groove 33. The lower side of the connecting post 42 is pressed against the bottom of the groove 33. A driving tool, such as an electric screwdriver, is connected to the nut body 43. When the driving tool is turned on, the nut body 43 is connected to the connecting post 42. The threaded tube 41 drives the screw body 3 to rotate. The stud 31 of the screw body 3 screws downward into the base. As the screw body 3 screws downward, the screw head 32 of the screw body 3 moves downward towards the base. When the screw head 32 moves to the upper surface of the base, the rotational resistance of the screw body 3 increases, and the torque between the nut body 4 and the screw body 3 increases. Specifically, the torque between the connecting post 42 and the threaded tube 41 increases. Since the moment of inertia of the threaded tube 41 is smaller than that of the connecting post 42, if the driving tool continues to drive, the connection between the connecting post 42 and the threaded tube 41 will break, preventing the screw body 3 from continuing to rotate. The remaining part of the nut body 4 can be removed from the upper end of the screw body 3. Figure 5 The screw body 3 is screwed into the base, and the threaded tube 41 remains in the screw hole 34.
[0025] As one implementation method, a cross groove 44 is provided on the upper side of the cap body 43.
[0026] The above settings facilitate the connection of the screwdriver to the cap 43.
[0027] As one implementation method, the outer peripheral surface of the cap body 43 is a hexagonal prism.
[0028] The above settings facilitate the connection of the wrench to the cap 43.
[0029] As one implementation, the cap body 43 is provided with a downward-opening receiving groove, the screw head 32 is placed in the receiving groove, and the cap body 43 covers the screw head 32.
[0030] The above settings improve the stability of the cap 43 on the screw head 32.
[0031] The screw head 32 of this application is cylindrical, and the inner circumferential surface of the receiving groove is cylindrical and fits against the screw head 32. After the cap body 43 wraps around the screw head 32, the cap body 43 and the screw head 32 maintain a high degree of coaxiality. The cap body 43 will not tilt, and the cap body 43 and the screw head 32 can rotate relative to each other. When the torque is too large, the cap body 43 and the screw head 32 can rotate relative to each other so that the connecting post 42 and the threaded tube 41 can be unscrewed.
[0032] As one implementation method, the lower side of the connecting post 42 abuts against the bottom of the groove 33.
[0033] As one implementation method, the groove 33 is a regular hexagon.
[0034] The above settings facilitate the unloading of the screw body 3.
[0035] After the screw body 3 of this application is tightened onto the base, the groove 33 is exposed on the upper end of the screw body 3. An Allen wrench can be inserted into the groove 33 and the screw body 3 can be rotated to unscrew the screw body 3 from the base.
[0036] It should be understood that those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.
Claims
1. A torque-limiting fastening screw, characterized in that, The device includes a screw body and a nut body. The screw body includes a stud and a screw head fixedly connected to the upper end of the stud. The outer diameter of the screw head is larger than the outer diameter of the stud. A groove is provided on the upper side of the screw head, and a downwardly extending screw hole is provided at the bottom of the groove. The nut body includes a threaded tube, a connecting post, and a cap body. The threaded tube is threaded into the screw hole. The outer diameter of the connecting post is larger than the outer diameter of the threaded tube and is fixedly connected to the upper end of the threaded tube. The cap body is fixedly connected to the upper end of the connecting post and is used to connect a driving tool.
2. The torque-limiting fastening screw according to claim 1, characterized in that, A cross groove is provided on the upper side of the cap.
3. The torque-limiting fastening screw according to claim 1, characterized in that, The outer circumferential surface of the cap is a hexagonal prism.
4. A torque-limiting fastening screw according to claim 1, characterized in that, The cap body is provided with a downward-opening receiving groove, the screw head is placed in the receiving groove, and the cap body covers the screw head.
5. A torque-limiting fastening screw according to claim 1, characterized in that, The lower side of the connecting post abuts against the bottom of the groove.
6. A torque-limiting fastening screw according to claim 1, characterized in that, The groove is in the shape of a regular hexagon.