Threaded Fastener With Fracturing Wings For Multi-Layer Drilling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Threaded fasteners fail when self-drilling through wood and into steel due to rapid advancement, causing a fractured drill point tip, as the threads remain engaged in wood and force the screw to advance through steel at a constant rate without allowing sufficient time for self-drilling.
Innovation Solution
A threaded fastener design featuring a shank with a non-threaded portion, a threaded portion, a tip, and wings that form a passage as it advances, allowing the wings to fracture upon engaging steel, enabling the threaded portion to further advance while an enlarged portion seats in the passage to resist movement perpendicular to the fastener's axis.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the threaded fastener uses a self-drilling tip to rapidly advance through wood and foam insulation, then installation speed is improved, but the drill point tip fractures when advancing through steel substrate
Solution Approach 1:
The shank is segmented into distinct functional zones: a non-threaded portion with an enlarged portion for wood engagement, a threaded portion for steel engagement, and a tip for self-drilling. This segmentation allows each zone to perform its specific function optimally without interfering with other zones, resolving the contradiction by enabling the tip to drill steel at appropriate speeds while the threaded portion provides secure fastening.
Solution Approach 2:
The non-threaded portion acts as an intermediary element between the self-drilling tip and the threaded portion. It provides a transition zone that allows the tip to advance through steel at controlled speeds while preventing the threaded portion from engaging too early in the wood, thereby preventing tip fracture while maintaining installation speed.
2Productivity
If the threads remain engaged in wood during steel drilling, then the fastener advances at a constant rate, but the drill point tip fractures from excessive advancement speed
Solution Approach 1:
The shank is divided into a non-threaded portion and a threaded portion positioned at different longitudinal locations. This spatial segmentation ensures that the threaded portion does not engage the wood substrate simultaneously with the tip engaging the steel substrate, allowing controlled advancement rates during steel drilling without causing tip fracture.
Solution Approach 2:
The solution addresses the advancement rate control problem by utilizing the longitudinal dimension of the shank. By positioning the threaded portion and non-threaded portion at different locations along the longitudinal axis, the fastener creates a staged engagement sequence that naturally controls the advancement rate through steel without requiring additional control mechanisms.
3Ease of manufacture
If the fastener uses a single continuous shank design, then manufacturing is simplified, but the fastener cannot effectively manage drilling and fastening processes through multiple layers
Solution Approach 1:
The shank is segmented into functional zones (non-threaded portion, threaded portion, tip) with different geometries and properties. This segmentation provides adaptability for different substrates and drilling depths while maintaining a single continuous structure that can be manufactured in one piece, balancing manufacturing simplicity with multi-layer fastening capability.
Solution Approach 2:
Different portions of the shank have different local qualities: the tip has a self-drilling geometry for steel, the non-threaded portion has an enlarged diameter for wood engagement, and the threaded portion has threads for steel fastening. This local differentiation enables effective multi-layer fastening while the overall continuous structure maintains manufacturing simplicity.
Data Source
AI summary
A threaded fastener is provided. The threaded fastener includes a shank having a non-threaded portion and a threaded portion. A tip extends from the threaded portion and a head extends from the non-threaded portion. A plurality of wings extend from the shank and are configured to form a passage as the threaded fastener advances. An enlarged portion is configured to seat in the passage formed by the plurality of wings with the threaded fastener in an installed arrangement.