Clinching Punch Taper Angle for Joint Strength and Tool Life
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing clinching technologies face challenges in creating strong clinch joints, particularly when joining sheets of differing thicknesses, as they often result in high stress concentrations and tool misalignments, leading to reduced tool life and undesirable material deformation such as tearing.
Innovation Solution
A clinching punch with a specifically dimensioned tapered surface, featuring a 20-35 degree angle, is used to improve the strength of the clinch joint by controlling material flow and interlocking deformation, with the taper angle determined by a formula that considers the thicknesses of the workpieces to ensure a consistent and thicker joint formation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Duration of action of stationary object
If a conventional punch with small or no taper is used, then the tool structure is simple, but high stress concentrations occur and tool life is reduced during high pressure operations
Solution Approach 1:
The patent changes the geometric parameter of the punch tip by introducing a specific taper angle (20-35 degrees) to optimize the stress distribution during clinching operations, thereby reducing stress concentrations and extending tool life
2Duration of action of stationary object
If a punch with larger taper angle is used, then stress concentrations are reduced and tool life is improved, but material deformation such as tearing increases
Solution Approach 1:
The patent optimizes the taper angle parameter within a specific range (20-35 degrees) to achieve the best balance between reducing stress concentrations and controlling material deformation, preventing both excessive wear and material tearing
3Adaptability or versatility
If sheets of differing thicknesses are joined, then the clinching apparatus can handle varied workpieces, but high stress concentrations and tool misalignments occur
Solution Approach 1:
The optimized taper angle (20-35 degrees) helps accommodate variations in sheet thickness by distributing the deformation more evenly, reducing misalignment issues and improving reliability when joining sheets of differing thicknesses
4Strength
If a conventional punch design is used, then the device complexity is low, but the joint strength is insufficient
Solution Approach 1:
The patent improves joint strength by optimizing the taper angle parameter of the punch tip, achieving better clinch joint performance with a relatively simple geometric modification rather than a completely complex redesign
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
A clinching apparatus (11) includes a clinching punch (29) having a specifically dimensioned tapered surface (101) which improves the strength of a clinch joint created therewith. The tapered surface (101) adjacent a distal end (83) of the clinching punch (29) has an angle (F) of 20-35° relative to the distal end (83). A further aspect of a clinching apparatus (11) provides a tapered surface (101) adjacent a distal end (83) which is configured in accordance with a specific formula.