Steering Column Electrifying Path via Elastic Contact

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing steering apparatuses face challenges in ensuring a reliable electrifying path from the steering wheel to the car body due to low friction material coatings that hinder electrical conduction between the inner and outer columns, and resin coatings on spline-fitted portions that disrupt electrification paths.

Innovation Solution

A steering apparatus configuration that includes a conductive fixture fixing a guide member and an electrifying member to the inner column, with contact pieces that elastically deform and protrude semi-spherically to maintain contact with the outer column, ensuring a stable electrifying path through guide walls and reducing friction for smooth sliding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If low friction material coating is applied to reduce clamping friction force, then secondary collision energy absorption is improved, but electrification through contact surface between inner column and outer column is hindered

Engineering Contradiction:
Improvesecondary collision energy absorptionVSAvoidelectrification reliability
Core Design Contradiction:
Loss of energyVSReliability

Solution Approach 1:

The patent divides the contact interface into two distinct functional zones: a low friction coating area for energy absorption and a conductive contact area for electrification. The electrifying member with contact pieces creates a separate electrical conduction path that does not rely on the friction-reduced contact surface between inner and outer columns.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The electrifying member acts as an intermediary component that bridges the electrical connection between the steering wheel and car body. It includes conductive elements that make contact with both the inner column and outer column, ensuring electrical continuity independent of the low friction coating.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Object-affected harmful factors

If resin coating is applied to spline-fitted portion to prevent backlash noises, then noise emission is reduced, but electrification through spline-fitted portion is disrupted

Engineering Contradiction:
Improvebacklash noiseVSAvoidelectrification continuity
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The electrifying member serves as a mediator that creates an alternative electrical conduction path through the steering column assembly, bypassing the resin-coated spline connection. This ensures electrical continuity is maintained through other contact points that are not affected by the noise-reducing coating.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Loss of energy

If clamping force of tilt/telescopic adjustment mechanism is decreased to smoothly absorb secondary collision energy, then energy absorption is improved, but holding force decreases causing backlash

Engineering Contradiction:
Improvesecondary collision energy absorptionVSAvoidbacklash prevention
Core Design Contradiction:
Loss of energyVSStability of the object's composition

Solution Approach 1:

The patent changes the friction parameter at the contact interface by applying low friction material coating, which allows the system to absorb secondary collision energy smoothly without requiring high clamping force, thereby preventing backlash while maintaining stable component composition.

Inventive Principle:
Principle #35Parameter changes

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 ensures a reliable and stable electrifying path from the steering wheel to the car body, enhancing the reliability of electrical connections while minimizing friction and preventing backlash during secondary collisions.

Implementation Method 1

the electrifying member is made of a metal plate material and is in contact with the outer column at a predetermined contact pressure while getting elastically deformed

Methodology Applied
Scientific EffectElastic deformation: Elasticity

Implementation Method 2

contact pieces that elastically deform and protrude semi-spherically to maintain contact with the outer column, ensuring a stable electrifying path through guide walls and reducing friction for smooth sliding

Methodology Applied
Scientific EffectRolling contact friction reduction: Friction

Data Source

PatentEP3118084B1Steering device
Publication Date: 2018.10.10 NSK LTD
  • EP3118084B1 patent drawingFigure 1
  • EP3118084B1 patent drawingFigure 2
  • EP3118084B1 patent drawingFigure 3

AI summary

A steering apparatus is disclosed, which includes a steering shaft (3), an outer column (10), an inner column (11) fitted in the outer column, a guide member (31) received in a guide groove (25) formed in the outer column and fitted to the inner column (11), and an electrifying member (40) fitted to the inner column inwardly of the guide groove and getting in contact with the outer column (10).