Steering Device Sliding Friction Impact Absorption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing steering devices face challenges in achieving improved impact absorbing performance while minimizing size in the front-rear direction, as the telescopic and collapse stroke regions typically require increased dimensions.
Innovation Solution
The steering device incorporates a slit in the outer column, a switching unit, and a hanger bracket with a guide hole and sliding friction portion, allowing the inner column to move forward with the hanger bracket, overlapping the telescopic engagement and guide holes, which reduces the overall length and enhances impact absorption through sliding friction.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the telescopic stroke region and collapse stroke region are arranged in the front-rear direction, then the impact absorbing performance is improved, but the size of the steering device in the front-rear direction increases
Solution Approach 1:
The patent applies dimensionality change by allowing the telescopic engagement portion and guide hole to overlap in the front-rear direction, effectively utilizing the radial dimension (width) to accommodate both stroke regions simultaneously. This transforms the linear arrangement into a spatial overlap configuration, reducing the overall front-rear length while maintaining both telescopic and collapse stroke functions.
Solution Approach 2:
The patent implements nesting by placing the telescopic engagement portion and guide hole in an overlapping configuration where one structure is positioned within or alongside the other in the radial direction. This nested arrangement allows both the telescopic stroke region and collapse stroke region to coexist in a compact space, reducing the front-rear dimension while preserving impact absorption capability.
2Adaptability or versatility
If the inner column is allowed to move with respect to the outer column during telescopic stroke, then the adjustability is improved, but the structural stability during collapse stroke deteriorates
Solution Approach 1:
The patent applies dynamics by implementing a switching mechanism that changes the structural configuration based on the operational phase. During telescopic stroke, the switching unit allows relative movement between the inner and outer columns for adjustability. During collapse stroke, the switching unit activates to restrict this relative movement, providing structural stability. This dynamic switching enables the system to adapt its degrees of freedom according to the required function.
Solution Approach 2:
The patent segments the movement control into two distinct phases using the switching unit. The switching unit divides the column structure's behavior into a telescopic mode (allowing movement) and a collapse mode (restricting movement). This segmentation allows independent optimization of both telescopic adjustability and collapse stability without compromising either function.
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 configuration effectively alleviates impact loads over the entire collapse stroke, improving impact absorbing performance while reducing the device's size in the front-rear direction, securing a sufficient collapse stroke even with shorter column lengths.
Implementation Method 1
A sliding friction portion that slides on at least one of the inner column and the hanger bracket in accordance with movement of the inner column with respect to the hanger bracket is provided between the inner column and the hanger bracket
Data Source
AI summary
A steering device includes an outer column, an inner column, and a hanger bracket. The inner column is configured such that the inner column and a fixation member move forward with respect to the hanger bracket in a case where a load in a forward direction that acts on the inner column is equal to or greater than a predetermined value in the locked state. A sliding friction portion that slides on at least one of the inner column and the hanger bracket in accordance with movement of the inner column with respect to the hanger bracket is provided between the inner column and the hanger bracket.