Steering Column Lock Bolt Rack and Pinion Actuation

Solution Overview

Problem

Current electronic steering column locks (ECLs) face inefficiency due to the use of leadscrews or cams, which require larger motors and electronics to generate the torque needed for actuating the lock bolt, resulting in friction-related inefficiencies.

Innovation Solution

A system with a motor-driven platform featuring driving and driven ramps that convert rotary motion into linear motion for the lock bolt, eliminating the need for friction interfaces and allowing for efficient locking and unlocking of the steering column.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If leadscrew or cam mechanisms are used to convert rotary motion to linear motion for lock bolt actuation, then the locking function is achieved, but friction losses increase and motor size must be enlarged to generate sufficient torque

Engineering Contradiction:

Improvefriction lossesVSAvoidmotor torque requirement

Core Design Contradiction:

Loss of energyVSPower

Solution Approach 1:

The patent replaces the traditional leadscrew or cam mechanism with a rack and pinion gear system. This substitution eliminates the friction interface problems inherent in leadscrews and cams, as the gear-based mechanism provides more efficient torque transmission with reduced energy losses. The pinion gear engages with the rack on the lock bolt to directly convert rotary motor motion to linear bolt movement without the sliding friction of leadscrews or the complex geometry of cams.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Device complexity

If leadscrew or cam mechanisms are used for lock bolt actuation, then the locking function is achieved, but the motor and electronics must be upsized to compensate for inefficiency

Engineering Contradiction:

Improvemotor and electronics sizeVSAvoidactuation efficiency

Core Design Contradiction:

Device complexityVSLoss of energy

Solution Approach 1:

The patent replaces the traditional leadscrew or cam mechanism with a rack and pinion gear system. This substitution eliminates the friction interface problems inherent in leadscrews and cams, as the gear-based mechanism provides more efficient torque transmission with reduced energy losses. The pinion gear engages with the rack on the lock bolt to directly convert rotary motor motion to linear bolt movement without the sliding friction of leadscrews or the complex geometry of cams.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Productivity

If friction interfaces like leadscrews or cams are used, then linear motion is generated, but inherent inefficiency requires larger components

Engineering Contradiction:

Improveactuation efficiencyVSAvoidcomponent size

Core Design Contradiction:

ProductivityVSQuantity of substance

Solution Approach 1:

The patent replaces the traditional leadscrew or cam mechanism with a rack and pinion gear system. This substitution eliminates the friction interface problems inherent in leadscrews and cams, as the gear-based mechanism provides more efficient torque transmission with reduced energy losses. The pinion gear engages with the rack on the lock bolt to directly convert rotary motor motion to linear bolt movement without the sliding friction of leadscrews or the complex geometry of cams.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 solution enhances efficiency by reducing the size and cost of electronic components, enabling effective locking and unlocking of the steering column with lower current requirements and improved mechanical advantages.

Implementation Method 1

A driving platform with driving ramps is disposed about the lock bolt and coupled to the output shaft. The driven platform is configured for interacting with each of the driving ramps to define a separation distance that depends upon a rotational position of the driving platform.

Methodology Applied

Scientific EffectRamp mechanism: Wedge

Data Source

PatentUS9221427B2System for selectively locking a steering column

Publication Date: 2015.12.29 STEERING SOLUTIONS IP HOLDING CORP

AI summary

A system for selectively locking a steering column comprises a lock bolt configured for translating along its axis so as to extend, in a first state, a first length from a base and, in a second state, a second length from the base. A motor is supported by a housing and has an output shaft. A driving platform with driving ramps is disposed about the lock bolt and coupled to the output shaft. A driven platform is disposed about the lock bolt, between a shoulder of the lock bolt and the driving platform. The driven platform is configured for interacting with each of the driving ramps to define a separation distance that depends upon a rotational position of the driving platform. The driven platform is also configured to cooperate with the shoulder of the lock bolt such that translation of the driven platform causes the lock bolt to translate.