Steering Wheel Elastic Member Gap Restriction for Vibration Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The frequency characteristics of vibrations in steering wheels with air bag devices are unstable due to elastic deformation issues, particularly when an annular gap in the elastic member is either not filled or fully filled with restriction portions, affecting the vibration absorption efficiency.
Innovation Solution
A steering wheel design with an elastic member featuring an annular gap shifted from the elastic main body, where multiple elastic restriction portions are strategically placed to fill the gap at specific locations, preventing excessive elastic deformation and stabilizing the frequency characteristics by controlling the reacting force.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the annular gap in the elastic member is not filled with restriction portions, then the elastic member can deform freely to absorb vibration energy, but the steering wheel oscillates with the elastic member as the fulcrum, making frequency characteristics unstable
Solution Approach 1:
The elastic member has different properties in different regions: the elastic main body can deform freely to absorb vibration energy, while the elastic restriction portions in the gap region limit deformation to prevent oscillation. This local differentiation of mechanical properties resolves the contradiction between vibration absorption and frequency stability.
2Stability of the object's composition
If the annular gap is fully filled with restriction portions, then oscillation is prevented, but the reacting force increases making the elastic member hard to deform, thus destabilizing frequency characteristics
Solution Approach 1:
Instead of fully filling the annular gap with restriction portions, only specific portions of the gap are filled. This partial filling provides enough restriction to prevent harmful oscillation while leaving sufficient space for the elastic member to deform and absorb vibration energy, thus avoiding excessive reacting force.
3Force
If the elastic member deforms in the gap region, then additional reacting force is generated, but this makes the elastic member harder to deform and destabilizes frequency characteristics
Solution Approach 1:
The elastic restriction portions are strategically placed in specific locations within the annular gap to control deformation at critical points without completely restricting deformation throughout the entire gap. This localized control prevents harmful oscillation while maintaining overall deformability for vibration absorption.
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 design effectively stabilizes the frequency characteristics of vibrations by restricting elastic deformation at targeted locations, enhancing vibration absorption without significantly increasing the reacting force, thus improving the overall vibration control efficiency.
Implementation Method 1
the elastic main body 54a, while elastically deforming at the same or near to the frequency of such vibration, vibrates with the air bag device 55, thereby absorbing the vibration energy of the steering wheel 50
Implementation Method 2
the air bag device 55 functions as a damper mass of a dynamic damper and the elastic main body 54a functions as a spring of the dynamic damper
Data Source
AI summary
A steering wheel includes: a support member inserted into a bag holder of an air bag device; a cylindrical slider; an annular damper holder configured to cover a part of the cylindrical slider; and an elastic member including an annular elastic main body interposed between the cylindrical slider and the annular damper holder, wherein: the air bag device configured to act as a damper mass of a dynamic damper; the annular elastic main body configured to act as a spring of the dynamic damper; an annular gap is formed with the elastic member at a portion shifted in the axial direction from the annular elastic main body; and the elastic member further includes elastic restriction portions configured to fill the annular gap to restrict the elastic deformation of the elastic member at the multiple portions of the annular gap spaced from each other in the peripheral direction.