Lever Switch with Non-Contact Magnetic Detection

Solution Overview

Problem

Conventional lever switches mounted near a vehicle's steering wheel face issues with stable electrical connections due to environmental factors like dust, gas, and humidity, requiring a hermetically sealed structure that increases component count and construction time.

Innovation Solution

The lever switch employs a rotator with a magnet and a magnetic detecting element that detects the rotation angle without mechanical contact, allowing reliable operation signal detection regardless of environmental conditions, reducing the number of components and construction time.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a hermetically sealed structure is used to protect against dust, gas, and humidity, then reliability is improved, but device complexity increases and manufacturing time increases

Engineering Contradiction:

Improvestability of electrical connectionVSAvoidnumber of components

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical contact-based electrical connection system with a non-contact magnetic detection system. The lever's position is detected through magnetic field changes rather than physical contact between electrical contacts, eliminating the need for hermetic sealing to protect electrical connections while maintaining reliable operation in harsh environments.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces a magnetic field as an intermediary between the lever mechanism and the detection system. The magnet attached to the lever modulates the magnetic field detected by the magnetic detecting element, allowing position information to be transmitted without mechanical contact or electrical connections that would require hermetic sealing.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If a hermetically sealed structure is used to protect against dust, gas, and humidity, then reliability is improved, but manufacturing time increases

Engineering Contradiction:

Improvestability of electrical connectionVSAvoidconstruction time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent replaces the mechanical contact-based electrical connection system with a non-contact magnetic detection system. The lever's position is detected through magnetic field changes rather than physical contact between electrical contacts, eliminating the need for hermetic sealing to protect electrical connections while maintaining reliable operation in harsh environments.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Device complexity

If mechanical contacts are used for signal detection, then device complexity is reduced, but reliability deteriorates due to environmental factors

Engineering Contradiction:

Improvesimplicity of structureVSAvoidstability of electrical connection

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The patent replaces the mechanical contact-based electrical connection system with a non-contact magnetic detection system. The lever's position is detected through magnetic field changes rather than physical contact between electrical contacts, eliminating the need for hermetic sealing to protect electrical connections while maintaining reliable operation in harsh environments.

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 configuration ensures reliable detection of lever operations without being affected by peripheral contaminants, simplifying the switch design and maintaining stable electrical connections, making it suitable for use near a vehicle's steering wheel.

Implementation Method 1

a magnet mounted on the rotator; a magnetic detecting element for detecting magnetism of the magnet

Methodology Applied

Scientific EffectMagnetism: Magnetism

Data Source

PatentUS7880572B2Lever switch

Publication Date: 2011.02.01 PANASONIC AUTOMOTIVE SYST CO LTD

AI summary

First rotator (25) and second rotator (29) rotating according to a rocking operation of outer lever (23) are provided. Magnetism of magnets (26) and (30) mounted on these rotators are detected by magnetic detecting elements (32) and (33) and output as a detected signal. Control portion (34) detects a rotation angle of each rotator from this detected signal and outputs an operation signal corresponding to the detected rotation angle.