Steering Wheel Decorative Member Adhesion Width Variation
Solution Overview
Problem
Steering wheel decorative members, such as sliced veneers, are prone to fractures and cracks under torsional loads due to stress concentration, which existing configurations fail to adequately address for impact resistance.
Innovation Solution
A decorative member is mounted on a resin member covering the steering wheel's ring core with an adhesion region that reduces in width from the center to the circumferential ends, dispersing stress and enhancing impact resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the decorative member is firmly fixed to the resin member with a wide adhesion region, then the attachment strength is improved, but stress concentration occurs under torsional loads causing fractures and cracks
Solution Approach 1:
The adhesion region is designed with non-uniform width, being wider at the central portion and narrower at the circumferential end portions. This local variation in adhesion area creates different stress distribution characteristics across the decorative member, allowing the central region to provide strong attachment while the end regions reduce stress concentration under torsional loads.
Solution Approach 2:
The width parameter of the adhesion region is deliberately changed across different locations of the decorative member's back surface. By making the adhesion width variable rather than constant, the stress distribution under load is optimized to prevent both detachment and fracture, resolving the contradiction between attachment strength and impact resistance.
2Ease of manufacture
If a uniform width adhesion region is used, then the manufacturing process is simplified, but stress concentrates at specific points under load
Solution Approach 1:
Instead of a uniform adhesion region, the invention implements local quality variation by making the adhesion width different at the central portion versus the circumferential end portions. This addresses the stress concentration problem while the adhesion region maintains a substantially straight configuration that is relatively simple to manufacture.
Solution Approach 2:
The adhesion region exhibits asymmetric width distribution along the circumferential direction, with the central portion having a greater width than the end portions. This asymmetric design optimizes stress distribution under torsional loads while remaining manufacturable through conventional adhesive application processes.
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 solution effectively reduces stress concentration and enhances impact resistance, preventing fractures and cracks in the decorative member, thereby improving the steering wheel's durability.
Implementation Method 1
an adhesion region in which the decorative member is adhered to the resin member is provided so that a width of the adhesion region is reduced from a central portion on a back surface facing the resin member toward circumferential end portions
Data Source
AI summary
A steering wheel decorative member configured to be mounted on a resin member covering a periphery of a ring core of a steering wheel. An adhesion region in which the decorative member is adhered to the resin member is provided so that a width of the adhesion region is reduced from a central portion on a back surface facing the resin member toward a circumferential end portion.