Steering Wheel Spokes with Central Holes for Impact Absorption
Solution Overview
Problem
Two-spoke type steering wheels face challenges in absorbing impact loads effectively due to limited bending deformation and reaction force generation, particularly when impact loads are applied to the rim's lower end or joining points, leading to inadequate displacement characteristics and stress concentration.
Innovation Solution
The steering wheel design incorporates first and second spokes with circular holes at their centers, which enhance bending deformation while maintaining torsional rigidity, allowing for efficient absorption of impact loads through controlled deformation of the rim and spokes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If holes are added to the spokes to increase bending deformation, then impact load absorption is improved, but torsional rigidity may be compromised
Solution Approach 1:
The patent applies local quality by creating holes specifically at bending deformation portions of the spokes, while maintaining the integrity of other structural areas. This localized modification allows bending deformation to occur at specific points without compromising the overall torsional rigidity of the spoke structure.
Solution Approach 2:
The spoke structure is segmented into different functional portions: bending deformation portions with holes for impact absorption, and other portions maintaining structural integrity for torsional stability. This segmentation allows different parts of the same component to serve different functions under different loading conditions.
2Adaptability or versatility
If the number of spokes is reduced to two, then design appeal and visibility are improved, but impact load absorption capability deteriorates
Solution Approach 1:
The patent changes the structural parameters of the spokes by adding holes at specific locations to modify their deformation characteristics. This allows two-spoke steering wheels to achieve adequate impact load absorption through controlled bending deformation, overcoming the limitation of having fewer spokes while maintaining design appeal.
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 holes in the spokes increase bending deformation, enabling effective absorption of impact loads without compromising torsional rigidity, thus providing desired displacement characteristics and ensuring the rim can absorb impact loads efficiently.
Implementation Method 1
The holes are formed in portions of the first and second spokes, and thus bending deformation is increased when an impact load is applied to one of the joining points of the rim and the first and second spokes.
Implementation Method 2
The first spoke has a circular first hole in a portion of the first spoke located at a middle in a longitudinal direction of the first spoke and at a center in a widthwise direction of the first spoke. The second spoke has a circular second hole in a portion of the second spoke located at a middle in a longitudinal direction of the second spoke and at a center in a widthwise direction of the second spoke.
Implementation Method 3
Each of the first and second spokes is in a plate shape... capable of torsional deformation... the spoke to which the impact load is applied and the spoke joined to the six o'clock position on the clock (lower end portion) can be deformed about deformation points on their base end portions on the boss side in a direction in which the rim is retreated from the driver, while withstanding the deformation by the impact load.
Data Source
AI summary
A first spoke connects a first point of a boss and a first joining point of a rim. A second spoke connects a second point of the boss different from the first point of the boss and a second joining point of the rim opposite to the first joining point of the rim to the boss. Each of the first and second spokes is in a plate shape. The first spoke has a circular first hole in a portion of the first spoke located at a middle in a longitudinal direction of the first spoke and at a center in a widthwise direction of the first spoke. The second spoke has a circular second hole in a portion of the second spoke located at a middle in a longitudinal direction of the second spoke and at a center in a widthwise direction of the second spoke.