Self-drilling self-tapping screw capable of stopping return
By setting up an inverter at the lower end of the thread section of the drilling tail self-tapping screw and setting up a chip drain at the bottom of the drilling tail, the problems of hardness of the plates and screws being withdrawn are solved, and better solidification and drilling are achieved Fluency.
Patent Information
- Application Number
- CN202421280307.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-05
- Publication Date
- 2025-01-10
- Estimated Expiration
- 2034-06-05
AI Technical Summary
When using plates with relatively high hardness, existing drilling tail self-tapping screws may be returned due to insufficient joint force, and the screws will exit when the force is insufficient during the tapping process, affecting the fixing effect and efficiency.
A reversible drill tail self-tapping screw is designed. The lower end of the thread section is equipped with an inverted button, which gradually decreases in the rotation direction, and a chip drain is set at the bottom of the drill tail. The flange is located at the screw head and thread section. The diameter is larger than the thread section.
By squeezing the inner wall of the plate screw holes inverted, the screws are prevented from returning, the joint force is enhanced, the firmness of the fixing is ensured, and the drilling flow and compacting the plate is improved through chip drainage grooves.
Smart Images
Figure CN222334211U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a fastener, in particular to a non-returnable self-drilling screw. Background Art
[0002] The drill tail self-drilling screw is a fastener with a drill tail and a thread, which is mainly used to fix building boards. The drill tail of the drill tail self-drilling screw is used to form a hole in the building board, and the thread is used for tapping operations, so that the drill tail self-drilling screw is fixed to the building board.
[0003] However, some plates are too hard, and after the drill-tip self-tapping screws are tapped, they may retreat a certain distance due to insufficient engagement force, affecting the fixing effect of the plate. In addition, during the tapping process, if the force of tightening the screw is slightly insufficient, the screw may retreat a certain distance, affecting efficiency. Utility Model Content
[0004] The technical solution of the utility model is aimed at the above situation. In order to solve the above problem, a non-returnable drill-type self-drilling screw is provided, which has a screw head, a threaded section and a drill tail, wherein the screw head, the threaded section and the drill tail are arranged in sequence. The drill-type self-drilling screw also has an undercut, which is located at the lower end of the threaded section and is adjacent to the thread of the threaded section, and the width of the undercut gradually decreases along the rotation direction of the thread.
[0005] Furthermore, there are multiple undercuts, and the multiple undercuts are evenly arranged along the rotation direction of the thread.
[0006] Furthermore, the length of the undercut portion of the thread segment is 1 / 5 to 1 / 2 of the total length of the thread segment.
[0007] Furthermore, the drill tail self-tapping screw has a plurality of chip removal grooves, and the chip removal grooves extend from the bottom of the drill tail to the threaded section.
[0008] Furthermore, the self-drilling screw also has a flange, which is located between the screw head and the threaded section, and the diameter of the flange is greater than the diameter of the threaded section.
[0009] After adopting the above technical scheme, the beneficial effect of the utility model is as follows: for the drill-tail self-tapping screw of the utility model, since the lower end of the threaded section is provided with an undercut, during the tapping process and after the tapping is completed, the undercut can be used to clamp the inner wall of the screw hole of the plate to prevent the drill-tail self-tapping screw from returning, thereby ensuring the firmness of the fixation. BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Figure 1 The utility model is a schematic diagram of a self-drilling screw. DETAILED DESCRIPTION
[0011] The technical solution of the utility model is further described below by way of embodiments:
[0012] The utility model provides a self-drilling screw with a check function, such as Figure 1 As shown, the drill tail self-drilling screw comprises a screw head 1, a threaded section 2, a drill tail 3 and an undercut 4, wherein the screw head 1, the threaded section 2 and the drill tail 3 are arranged in sequence, the undercut 4 is located at the lower end of the threaded section 2 and is adjacent to the thread of the threaded section 2, and the width of the undercut 4 gradually decreases along the rotation direction of the thread (i.e., the tip of the undercut 4 faces the same direction as the rotation direction of the thread).
[0013] When using the drill-tail self-tapping screw, the screw head 1 is used to cooperate with a screwdriver to perform the screwing operation; the threaded section 2 is used to tap the plate and form a fixation with the plate; the drill tail 3 is used to drill a hole in the plate located on the bottom surface before tapping to form the prototype of the screw hole.
[0014] In the utility model, since the lower end of the threaded section 2 is provided with an undercut 4, the undercut 4 can be used to clamp the inner wall of the screw hole of the plate during and after the tapping process to prevent the drill-tail self-tapping screw from returning, thereby ensuring the firmness of the fixation.
[0015] Specifically, there are multiple undercuts 4, and the multiple undercuts 4 are evenly arranged along the rotation direction of the thread. Among them, the multiple undercuts 4 can enhance the joining force, so that the self-drilling screw and the plate are fixed more firmly.
[0016] More specifically, the length L2 of the portion of the thread segment 2 where the undercut 4 is provided is 1 / 5 to 1 / 2 of the total length L1 of the thread segment 2 .
[0017] Specifically, the drill tail self-tapping screw also has a plurality of chip removal grooves 5, which extend from the bottom of the drill tail 3 to the threaded section 2. The chip removal grooves 5 can be provided to discharge debris during drilling and improve the smoothness of drilling. In this embodiment, there are a plurality of chip removal grooves 5, and the plurality of chip removal grooves 5 are evenly arranged around the axis of the drill tail self-tapping screw.
[0018] Specifically, the self-drilling screw further has a flange 6, which is located between the screw head 1 and the threaded section 2, and the diameter of the flange 6 is greater than the diameter of the threaded section 2. The flange 6 can be provided to press the plate tightly and prevent impurities from entering the through hole of the plate.
Claims
1. A self-drilling screw with a non-return function, comprising a screw head, a threaded section and a drill tail, wherein the screw head, the threaded section and the drill tail are arranged in sequence, and characterized in that: The self-drilling screw also has an undercut, which is located at the lower end of the threaded section and is adjacent to the thread of the threaded section, and the width of the undercut gradually decreases along the rotation direction of the thread.
2. The non-returnable self-drilling screw according to claim 1, characterized in that: There are multiple undercuts, and the multiple undercuts are evenly arranged along the rotation direction of the thread.
3. The non-returnable self-drilling screw according to claim 1, characterized in that: The length of the undercut portion of the thread segment is 1 / 5 to 1 / 2 of the total length of the thread segment.
4. The non-returnable self-drilling screw according to claim 1, characterized in that: The drill tail self-tapping screw has a plurality of chip removal grooves, and the chip removal grooves extend from the bottom of the drill tail to the thread section.
5. The non-returnable self-drilling screw according to claim 1, characterized in that: The self-drilling screw also has a flange, which is located between the screw head and the threaded section, and the diameter of the flange is greater than the diameter of the threaded section.