Concrete Screw Thread Segmentation for Slant Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional concrete screws tend to slant and wobble during screw-in movement due to sharp edges, resulting in increased frictional force and torque requirements, making the operation effortful and time-consuming.
Innovation Solution
A screw design featuring a frusto-conical tip with a first thread section, two second thread sections, and a third thread section with an arc-shaped cross-section, including V-shaped notches and an asymmetric thread surface design to reduce friction and accommodate swarf, ensuring a stable and even cutting force.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional concrete screws with sharp thread edges are used, then the screw can cut and ream concrete material effectively, but the screw is liable to slant and wobble during starting screw-in movement, increasing frictional force and torque requirements
Solution Approach 1:
The thread structure is divided into multiple sections: a first thread section with first threads for initial engagement, a second thread section with second threads for cutting and reaming, and a third thread section with third threads for final tightening. This segmentation allows each section to perform its specific function optimally, reducing overall operational effort while maintaining productivity.
Solution Approach 2:
The first thread section with first threads performs preliminary action by providing initial engagement and guidance before the main cutting threads engage. This preliminary engagement prevents slant and wobble during starting movement, reducing frictional force and torque requirements before the main cutting action begins.
2Ease of manufacture
If conventional concrete screws with uniform thread structure are used, then the screw can be manufactured simply, but the screw-in movement is effortful and time-consuming due to increased frictional force
Solution Approach 1:
The thread structure is divided into multiple sections: a first thread section with first threads for initial engagement, a second thread section with second threads for cutting and reaming, and a third thread section with third threads for final tightening. This segmentation allows each section to perform its specific function optimally, reducing overall operational effort while maintaining productivity.
Solution Approach 2:
The thread parameters (such as pitch, depth, and profile) are changed across different sections. The first threads have different parameters optimized for initial engagement, the second threads have parameters optimized for cutting and reaming, and the third threads have parameters optimized for final tightening. This parameter variation reduces frictional force during screw-in movement while maintaining manufacturing feasibility.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A screw includes a head (31) and a shank (32) extending from the head to terminate at a frusto-conical tip portion (321). A first thread section (33) has asymmetric upper and lower thread surfaces (331, 332), a plurality of V-shaped notches (333) formed at a juncture of the surfaces (331, 332), and a fillet surface (302) formed at a juncture between the shank (32) and the upper thread surface (331). Two second thread sections (34) are disposed adjacent to each other and spaced apart from the first thread section (33). A third thread section (35) extends from the first thread section (33) toward the tip portion (321) and has an outer surface of an arc-shaped cross-section. The screw-in movement of the screw is guided by the third thread section to prevent the screw from being slanted relative to a concrete object.