Inductive Sensor Door Handle System for Wear-Free Position Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing door handle systems for motor vehicles face issues with microswitches requiring large installation space, being prone to wear, and sensitive to external influences, while Hall sensors increase manufacturing costs due to the need for magnetic material.

Innovation Solution

A door handle system utilizing an inductive sensor that detects changes in electrically conductive material, eliminating the need for magnetic material and providing a compact, wear-free, and vibration-resistant solution for position detection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If microswitches are used to detect the position of moving components, then the position detection function is achieved, but the installation space required is large and the sensor is prone to wear and sensitive to external influences

Engineering Contradiction:
Improvesensor reliabilityVSAvoidinstallation space
Core Design Contradiction:
ReliabilityVSArea of stationary object

Solution Approach 1:

The patent replaces mechanical microswitches with inductive sensors that use electromagnetic fields for contactless detection. This substitution eliminates mechanical wear and contact issues while reducing the physical space required for sensor installation, as inductive sensors can be more compact and do not require the same mechanical clearance as microswitches.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces an electrically conductive detection element as an intermediary between the moving component and the inductive sensor. This detection element modulates the inductive sensor's output signal based on its position, enabling reliable position detection without direct mechanical contact between the sensor and moving parts, thus improving reliability while maintaining compact design.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If Hall effect sensors are used to detect the position of moving components, then position detection is achieved, but magnetic material is required which increases manufacturing costs

Engineering Contradiction:
Improveposition detection precisionVSAvoidmanufacturing cost
Core Design Contradiction:
Measurement precisionVSEase of manufacture

Solution Approach 1:

The patent changes the detection principle from magnetic field-based (Hall effect) to electromagnetic induction-based. By using inductive sensors that detect changes in inductance caused by the position of electrically conductive materials, the system achieves precise position detection without requiring magnetic materials, thereby reducing manufacturing costs while maintaining measurement precision.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent applies different material properties to different parts of the system: the detection element is made of electrically conductive material (such as metal) rather than magnetic material. This localized use of electrically conductive material in the detection element allows the inductive sensor to achieve precise position detection without requiring magnetic materials throughout the system, reducing overall manufacturing costs.

Inventive Principle:
Principle #3Local quality

3Area of stationary object

If inductive sensors are used instead of microswitches, then installation space is reduced and reliability is improved, but the detection mechanism becomes more complex

Engineering Contradiction:
Improveinstallation spaceVSAvoiddetection mechanism complexity
Core Design Contradiction:
Area of stationary objectVSDevice complexity

Solution Approach 1:

The inductive sensor serves multiple functions: it provides contactless position detection, eliminates mechanical wear, reduces installation space requirements, and maintains reliability in harsh environments. The detection element also serves as both a mechanical component (attached to the moving part) and a sensing element (modulating the inductive field), reducing the need for separate sensing components and simplifying the overall system architecture.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 inductive sensor enables a cost-effective, reliable, and compact door handle system design with reduced installation space requirements, capable of detecting multiple positions and maintaining functionality under various environmental conditions.

Implementation Method 1

an inductive sensor measures the change in inductance caused by changes in the amount of an electrically conductive material, such as metal, within the sensor's detection range

Methodology Applied
Scientific EffectInductive sensing: Electromagnetic Induction

Implementation Method 2

the inductive sensor forms a resonant circuit whose frequency changes when the amount of electrically conductive material in the sensor's detection range changes

Methodology Applied
Scientific EffectResonance: Resonance

Data Source

PatentEP3507436B1Door handle system for a motor vehicle
Publication Date: 2020.12.02 WITTE AUTOMOTIVE GMBH
  • EP3507436B1 patent drawingFigure 1
  • EP3507436B1 patent drawingFigure 2
  • EP3507436B1 patent drawingFigure 3

AI summary

The invention relates to a door handle system for a motor vehicle, comprising a fastening bracket, at least one component which can be moved relative to the fastening bracket, and at least one sensor used to detect a position of the movable components relative to the fastening bracket.