Steering Column Spindle Drive Nesting for Compactness

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional steering columns for steer-by-wire systems are not compact or safe due to exposed spindle drives, which increase the structure's volume and require additional protective devices, making them unsuitable for autonomous driving applications where space efficiency and safety are critical.

Innovation Solution

The steering column design integrates the spindle drive within the casing tubes, using a coaxial threaded spindle and nut arrangement, with the spindle drive protected from external influences, and incorporates a feedback actuator to provide haptic feedback, enhancing safety and compactness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the spindle drive is attached to the casing unit with the threaded spindle exposed on the outside, then the steering column can be adjusted longitudinally, but the structure becomes relatively voluminous and requires additional protective devices

Engineering Contradiction:
Improvelongitudinal adjustabilityVSAvoidsteering column volume
Core Design Contradiction:
Ease of operationVSVolume of moving object

Solution Approach 1:

The threaded spindle is integrated inside the telescopic casing tubes, with the outer casing tube receiving the inner casing tube in a nested arrangement. The spindle drive components are housed within the casing unit, eliminating the need for external exposure and reducing overall volume while maintaining adjustability functionality.

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The spindle drive is merged with the casing unit structure, where the threaded spindle is supported on one casing tube and the spindle nut is attached to the other casing tube. This integration combines the adjustment mechanism with the structural housing, eliminating separate protective devices and reducing volume.

Inventive Principle:
Principle #5Merging (Combining)

2Ease of operation

If the threaded spindle is exposed on the outside for longitudinal adjustment, then the steering column can be adjusted, but moving or rotating parts become accessible from the vehicle interior creating safety issues

Engineering Contradiction:
Improvelongitudinal adjustabilityVSAvoidsafety
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The threaded spindle and spindle nut are nested within the telescopic casing tubes, which act as protective housings. The outer casing tube receives the inner casing tube, creating an enclosed environment that prevents access to moving parts from the vehicle interior while maintaining the adjustment function.

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The threaded spindle is extracted from external exposure and relocated inside the casing unit. The spindle drive is integrated within the casing structure, removing the safety hazard of exposed moving parts while preserving the longitudinal adjustment capability through the enclosed telescopic mechanism.

Inventive Principle:
Principle #2Taking out (Extraction)

3Volume of moving object

If the steering column is designed to be compact for autonomous driving, then space efficiency improves, but the spindle drive becomes vulnerable to external influences

Engineering Contradiction:
Improvesteering column volumeVSAvoidexposure to external influences
Core Design Contradiction:
Volume of moving objectVSObject-affected harmful factors

Solution Approach 1:

The spindle drive components are nested within the telescopic casing tubes, creating a compact yet protected structure. The outer casing tube receives the inner casing tube, forming an enclosed housing that shields the spindle drive from external influences while maintaining compact dimensions suitable for autonomous driving applications.

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The spindle drive is merged with the casing unit, where the threaded spindle is supported on one casing tube and the spindle nut is attached to the other. This integration combines the adjustment mechanism with the protective housing, achieving compactness without vulnerability to external influences.

Inventive Principle:
Principle #5Merging (Combining)

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 results in a more compact, safe, and stowable steering column that improves driving safety and operating comfort by eliminating the need for external protective devices and allowing for quick deployment and retraction, suitable for autonomous driving scenarios.

Implementation Method 1

the threaded spindle extending within the first casing tube and the spindle nut on the second casing tube

Methodology Applied
Scientific EffectScrew mechanism: Screw

Data Source

PatentEP3386837B1Steering column for a steer-by-wire steering device
Publication Date: 2021.03.03 THYSSENKRUPP PRESTA AG
  • EP3386837B1 patent drawingFigure 1~3
  • EP3386837B1 patent drawingFigure 4~5
  • EP3386837B1 patent drawingFigure 6~7

AI summary

The present invention relates to an adjustable steering column (2) for a steer-by-wire steering device (1) of a motor vehicle, comprising an actuating unit, having a steering spindle (51) rotatably mounted about a longitudinal axis (21) in a casing unit (5), wherein the casing unit (5) comprises a first casing tube (54) in which at least one second casing tube (55) is arranged rotationally fixed with respect to the longitudinal axis (21) and mounted to move axially in a telescopic manner, wherein an actuating drive (7) is connected to the first (54) and the second casing tube (55), by which means the second casing tube (55) can be driven axially in and out with respect to the first casing tube (54), and which comprises a spindle drive having a threaded spindle (72) that is arranged parallel to the longitudinal axis (21) and can be driven in a rotational manner by an electric actuating motor (71), said spindle being supported on a casing tube (54) and screwed into a spindle nut (73) that can be rotationally fixed to the other casing tube (55). In order to provide a motor-adjustable steering column (2) which is more suitable for use in steer-by-wire steering systems (1), the invention proposes that the threaded spindle (72) extends inside the first casing tube (54), preferably coaxially, and the spindle nut (53) is attached on the second casing tube (55), preferably coaxially.