Auxiliary-Thread Self-Tapping Screw for Reduced Rolling Bending
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Self-tapping screws experience unfavorable bending during the rolling process, leading to increased installation difficulty and stress concentration, which affects their performance and efficiency.
Innovation Solution
A screw design featuring a primary thread and an auxiliary thread, where the auxiliary thread extends partially along the screw body, providing additional material and improved stress distribution, reducing bending and enhancing installation ease.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a self-tapping screw is formed using a traditional rolling process, then the threads are formed on the screw body, but high concentration of stresses occurs causing unfavorable bending of the screw
Solution Approach 1:
The screw thread is segmented into a primary thread and an auxiliary thread. The primary thread is formed by the traditional rolling process, while the auxiliary thread is formed separately using excess material from the rolling process. This segmentation allows the primary thread to provide the main fastening function while the auxiliary thread distributes stresses and reduces bending, thereby resolving the contradiction between ease of manufacture and stability of the screw composition.
2Productivity
If the rolling process is used to form threads, then the screw can be manufactured efficiently, but the high stress concentration makes installation more difficult and less efficient
Solution Approach 1:
The thread structure is divided into primary and auxiliary threads. The primary thread maintains manufacturing efficiency through the rolling process, while the auxiliary thread, formed from excess rolling material, reduces stress concentration during installation. This segmentation enables both high productivity during manufacturing and improved ease of operation during installation.
Solution Approach 2:
The excess material that normally causes stress concentration and bending during the rolling process is converted into a beneficial auxiliary thread. This auxiliary thread, formed from the same excess material, distributes stresses more evenly and reduces bending, thereby converting the harmful effect of excess material into a benefit that improves installation ease while maintaining manufacturing efficiency.
3Device complexity
If a single primary thread is used, then the screw structure is simple, but stress distribution is unfavorable leading to bending
Solution Approach 1:
The thread structure is segmented into a primary thread and an auxiliary thread. The primary thread provides the main fastening function with a relatively simple structure, while the auxiliary thread, positioned in the interpitch of the primary thread, improves stress distribution. This segmentation achieves better stress distribution without significantly increasing device complexity, as the auxiliary thread is formed from excess material during the same rolling process.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The screw design reduces bending and stress concentration, facilitating easier installation and improved performance by distributing stress more effectively during the rolling process.
Implementation Method 1
the auxiliary thread comprises excess material from the formation of the primary thread... the auxiliary thread comprises excess material from the rolling of the primary thread... providing additional material and improved stress distribution, reducing bending
Data Source
Figure 1
Figure 2a~2b
Figure 3a~3f
AI summary
The invention relates to a screw (100) comprising: a longitudinal body (120) having a first end (122) and a second end (124); a head portion (110) for receiving a driving force, the head portion adjacent the first end of the body; wherein the longitudinal body (120) comprises: a primary thread (130) helically extending between the first end (122) and the second end (124); and an auxiliary thread (140) separated from the primary thread, and helically extending from the first end at least partially towards the second end.