Anti-loosening screw
By designing thread structures with different pitches, a rubber ring at the head, and an expansion flap at the tail, the anti-loosening screw solves the problem of traditional screws loosening under vibration and long-term load, achieving a highly efficient anti-loosening effect and an environmentally friendly screw design.
Patent Information
- Application Number
- CN202520822875.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-27
- Publication Date
- 2026-02-27
- Estimated Expiration
- 2035-04-27
AI Technical Summary
Traditional screws are prone to loosening under vibration, impact, or long-term load. Existing anti-loosening technologies such as spring washers, lock nuts, and adhesive bonding have problems such as short lifespan, complex structure, or environmental unfriendliness.
A non-loosening screw was designed, which adopts an external thread structure with different pitches on the screw, with a rubber ring embedded in the head and an expansion flap and deformation groove at the tail. Through the triple anti-loosening mechanism of thread self-locking, elastic compression and mechanical engagement, combined with the radial elastic restoring force of the rubber ring and the deformation of the expansion flap, the vibration resistance is enhanced.
It significantly improves the screw's resistance to vibration and loosening, and has the advantages of simplified structure, maintenance-free operation and environmental friendliness. It achieves a dual anti-loosening mechanism in both dynamic and static aspects, thereby enhancing the screw's service life.
Smart Images
Figure CN223953061U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to fastener technical field, especially relates to a anti-loosening screw. BACKGROUND
[0002] As the most commonly used mechanical connecting piece, the anti-loosening performance of screw is very important. The traditional screw mainly relies on the thread friction to realize the fixation, but under the vibration, impact, temperature change or long-term load effect, the relative rotation between the thread pairs is easy to cause the loosening. The existing anti-loosening technology such as spring washer, locking nut, glue joint has obvious defects: the spring washer is limited by material fatigue, and the anti-loosening life is short; the locking nut structure is complex and inconvenient to disassemble; the glue joint is not environment-friendly, and the maintenance cost is high. SUMMARY
[0003] In order to solve the above problems, the utility model provides a kind of anti-loosening screw, which can effectively improve the service life of screw.
[0004] Therefore, the technical scheme of the utility model is as follows: an anti-loosening screw, comprising a head, a screw rod and a tail, at least two sections of external thread structure are provided on the screw rod, and the pitch of the thread near the tail is greater than the pitch of the thread near the head; the side of the head towards the screw rod is provided with an annular groove, and a rubber ring is embedded in the annular groove; the tail is provided with a hollow structure, and a plurality of axial slots are provided, and the slots divide the tail into a plurality of expansion petals.
[0005] On the basis of the above scheme and as a preferred scheme of the above scheme: a first deformation groove is provided at the junction of the tail and the screw rod, i.e. the first deformation groove is located above the expansion petal.
[0006] On the basis of the above scheme and as a preferred scheme of the above scheme: at least one second deformation groove is provided on the outside of the expansion petal, and the groove depth of the second deformation groove is less than that of the first deformation groove.
[0007] On the basis of the above scheme and as a preferred scheme of the above scheme: the hollow structure of the tail is a conical structure, forming an inclined surface on the inside of the expansion petal.
[0008] On the basis of the above scheme and as a preferred scheme of the above scheme: the tail is provided with 3-6 evenly arranged expansion petals.
[0009] On the basis of the above scheme and as a preferred scheme of the above scheme: the thread structure near the tail of the screw rod is a first external thread, and the thread near the head is a second external thread structure; the pitch of the first external thread is twice the pitch of the second external thread structure.
[0010] As a preferred scheme of the above scheme and on the basis of the above scheme: the rubber ring is made of silicone rubber or fluororubber, the rubber ring is installed in the annular groove, and the rubber ring is 0.2-0.4 mm higher than the head surface.
[0011] Compared with the prior art, the utility model has the advantages that:
[0012] 1. The integrated thread self-locking, elastic compression and mechanical engagement triple anti-loose path greatly improves the anti-vibration loosening capacity compared with the traditional single-point anti-loose scheme, and has the advantages of simple structure, maintenance-free and environmental protection.
[0013] 2. The threads on the screw rod are composed of external threads with different pitches, the large-pitch threads at the tail and the standard threads at the head form a pitch difference, axial tension is generated during tightening, the threads are continuously compressed, and the reverse rotation is inhibited by using the thread interference effect.
[0014] 3. The head is provided with a rubber ring, the rubber ring can generate radial elastic restoring force after being compressed, compensates the thread gap and absorbs vibration energy, and forms a dynamic and static double-state anti-loose mechanism with the thread self-locking.
[0015] 4. The tail is provided with an expansion petal, under the condition of continuous stress, the expansion petal can be deformed in cooperation with the deformation groove, the expansion petal expands outward and is clamped into the inner wall of the screw hole under rotation, forming surface contact engagement, if the inner wall of the screw hole cannot be cut, the expansion petal can be deformed under stress, thereby increasing the outer diameter of the bottom of the screw, so as to be clamped in the screw hole, realizing the synergistic enhancement of the radial expansion force and the axial pull-out resistance. BRIEF DESCRIPTION OF DRAWINGS
[0016] Figure 1 It is a structure schematic view of the embodiment 1;
[0017] Figure 2 It is a structure schematic view (another orientation) of the embodiment 1;
[0018] Figure 3 It is an initial state schematic view of the embodiment 1;
[0019] Figure 4 It is a schematic view of the bent state of the expansion petal under the locked state of the embodiment 1;
[0020] Figure 5 It is a schematic view of the extrusion deformation of the expansion petal under the locked state of the embodiment 1;
[0021] Figure 6 It is a structure schematic view of the embodiment 2.
[0022] In the figure, the head 1, the annular groove 11, the rubber ring 12, the screw rod 2, the first external thread 21, the second external thread structure 22, the tail 3, the slotted 31, the expansion petal 32, the first deformation groove 41, the second deformation groove 42, and the mounting hole 5 are marked. DETAILED DESCRIPTION
[0023] In the description of the utility model, it needs to explain that, for the orientation words, such as the term "center", "lateral (X)", "longitudinal (Y)", "vertical (Z)", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate the orientation and positional relationship based on the orientation or positional relationship shown in the drawings, and it is only for the convenience of narrating the utility model and simplifying the description, and it cannot be understood as indicating or implying that the device or element indicated must have a particular orientation, be constructed and operated in a particular orientation, and cannot be understood as limiting the specific protection scope of the utility model.
[0024] In addition, if the terms "first" and "second" are only used for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. Therefore, the "first" and "second" features defined can explicitly or implicitly include one or more features, and in the description of the utility model, the meaning of "several" and "several" is two or more than two, unless otherwise explicitly specified.
[0025] Referring to the drawings. The anti-loose screw described in the embodiment comprises a head 1, a screw rod 2 and a tail 3, at least two outer thread structures are arranged on the screw rod 2, the thread structure near the tail 3 of the screw rod 2 is a first outer thread 21, and the thread near the head 1 is a second outer thread structure 22;The pitch of the first outer thread 21 is twice the pitch of the second outer thread structure 22. The threads on the screw rod 2 are composed of outer threads with different pitches, and the tail large-pitch thread and the head standard thread form a pitch difference, which generates axial tension when tightening, thereby improving the anti-loose ability.
[0026] The head 1 is provided with an annular groove 11 on the side of the screw rod 2, and a rubber ring 12 is embedded in the annular groove 11;The rubber ring 12 is made of silicone rubber or fluorine rubber, the rubber ring 12 is installed in the annular groove 11, and the rubber ring 12 is 0.2-0.4mm higher than the surface of the head 1. The rubber ring 12 can generate radial elastic recovery force after being pressed, compensate the thread gap and absorb vibration energy, and form a dynamic and static double-state anti-loose mechanism with the thread self-locking.
[0027] The tail part 3 is provided with a hollow structure which is a conical structure, and a plurality of axial grooves 31 are arranged on the circumference of the tail part 3, the grooves 31 uniformly divide the tail part 3 into 3-6 expansion petals 32, the inner side of the expansion petals 32 forms an inclined surface to facilitate bending. A first deformation groove 41 is arranged at the joint between the tail part 3 and the screw rod 2, that is, the first deformation groove 41 is located above the expansion petals 32, under the condition of continuous stress, the expansion petals 32 can be deformed in cooperation with the first deformation groove 41, the expansion petals 32 expand outward to form surface contact engagement with the inner wall of the screw hole, so that the radial expansion force and the axial pull-out resistance are synergistically enhanced.
[0028] In the initial state, the expansion petals 32 below the screw are in an undeformed state, in use, the screw is screwed into the mounting hole 5, when the tail part of the screw does not reach the bottom, the mode is the same as the conventional mode; when the tail part 3 of the screw contacts the bottom of the mounting hole, the screw is continuously rotated downward, so that the expansion petals 32 are deformed under stress.
[0029] If the medium to be installed is concrete, wooden furniture, composite board and other products which can be conveniently cut and inserted by the expansion petals, when the expansion petals 32 are rotated and pressed, they are clamped into the side wall of the mounting hole 5, further strengthening the installation strength of the screw (see Figure 4 ).
[0030] If the medium to be installed is a hard material which is not convenient for the expansion petals to cut and insert, when the expansion petals 32 are rotated and pressed, they will be deformed by extrusion, so as to realize interference fit with the bottom of the mounting hole, further strengthening the installation strength of the screw (see Figure 4 ).
[0031] Embodiment 2
[0032] The structure of this embodiment is the same as that of embodiment 1, the difference lies in that the outer side of the expansion petals 32 is provided with two second deformation grooves 42, the groove depth of the second deformation grooves 42 is smaller than that of the first deformation groove 41, and the groove depth of the second deformation grooves closer to the tail part is smaller. The second deformation grooves 42 can be combined with the first deformation groove 41, so that the expansion petals 32 can be bent and expanded outward after being stressed, guiding the deformation direction of the expansion petals.
[0033] The above is only the preferred embodiment of the present application, the protection scope of the present application is not limited to the above-mentioned embodiments, any technical solution belonging to the idea of the present application is within the protection scope of the present application. It should be noted that, for ordinary technical personnel in the technical field, some improvements and decorations without departing from the principle of the present application are also considered as the protection scope of the present application.
Claims
1. A captive screw comprising a head, a shank, and a tail, characterized in that: The screw is provided with at least two external thread structures, and the pitch of the thread near the tail is greater than that of the thread near the head; the head is provided with an annular groove on the side of the screw, and a rubber ring is embedded in the annular groove; the tail is provided with a hollow structure and a plurality of axial grooves, and the tail is divided into a plurality of expansion petals by the grooves.
2. A tamperproof screw as claimed in claim 1, wherein: The tail is provided with a first deformation groove at the junction with the screw, i.e. the first deformation groove is located above the expansion petal.
3. A tamperproof screw as defined in claim 2 wherein: The outer side of the expansion petal is provided with at least one second deformation groove, and the groove depth of the second deformation groove is smaller than that of the first deformation groove.
4. A tamperproof screw as defined in claim 1 wherein: The hollow structure of the tail is a tapered structure, and an inclined surface is formed on the inner side of the expansion petal.
5. A tamperproof screw as defined in claim 1 wherein: The tail is provided with 3-6 evenly arranged expansion petals.
6. A tamperproof screw as defined in claim 1 wherein: The thread structure near the tail of the screw is a first external thread, and the thread near the head is a second external thread structure; the pitch of the first external thread is twice that of the second external thread structure.
7. A tamperproof screw as defined in claim 1 wherein: The rubber ring is made of silicone rubber or fluororubber, the rubber ring is installed in the annular groove, and the height of the rubber ring is 0.2-0.4 mm higher than the surface of the head.