Rolled Thread Screw End Geometry to Prevent Burr Formation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In-feed thread rolling methods often result in burrs and sharp edges on rolled thread screws, which complicate post-processing and reduce production yield.
Innovation Solution
The implementation of salient excess-thickness portions, such as columnar and truncated cone parts, on the blank, which are shaped through thread rolling to form concave surfaces and salient parts, preventing burrs and allowing for flat axial end surfaces, thereby reducing the need for deburring and improving yield.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If in-feed thread rolling is used to manufacture rolled thread screws, then individual screws can be processed efficiently, but burrs and sharp edges are generated on the rolled thread screws
Solution Approach 1:
The patent applies preliminary action by providing excess thickness portions (columnar parts and truncated cone parts) on the end parts of the blank before thread rolling. These excess-thickness portions prevent the end-part wall surfaces from falling down during thread rolling, thereby preventing burr formation in advance while maintaining efficient individual screw processing
2Ease of manufacture
If burrs are generated on rolled thread screws, then post-processing such as deburring is required, but this increases manufacturing complexity and reduces production yield
Solution Approach 1:
The patent converts the potential harm of material excess into a benefit by designing excess-thickness portions that prevent burr formation. The excess material acts as a protective feature during thread rolling, and the resulting concave surfaces and salient parts on the axial end surfaces eliminate the need for deburring operations, thereby improving production yield without sacrificing manufacturing simplicity
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
This approach effectively minimizes burr formation, simplifies quality checking, and enhances the production yield by ensuring flat axial end surfaces and longer effective screw lengths.
Implementation Method 1
a processing step of plastically deforming the blank into a rolled thread screw
Data Source
AI summary
A rolled thread screw includes: a screw part having, on an outer circumferential part of the screw part, thread crests and thread grooves disposed alternately along an axial direction of the rolled thread screw; and a columnar part adjoining at least one of both sides of the screw part in the axial direction. An axial end surface of the columnar part is provided with: a first concave surface concave in the axial direction; a second concave surface positioned to an outer circumference of the first concave surface and being concave in the axial direction; and a salient part positioned on a boundary between the first concave surface and the second concave surface and projecting further than a bottom of the first concave surface and a bottom of the second concave surface, the salient part extending in an arc-like shape along a circumferential direction of the columnar part as viewed in the axial direction.