Differential Lock Actuator Reed Switch Detection

Solution Overview

Problem

Conventional differential lock detection assemblies are prone to wear, require tight tolerances, and can be costly and time-consuming to implement, often resulting in reduced service life and difficulty in detecting the state of the differential locking mechanism.

Innovation Solution

A differential lock actuator with a removable cap housing that encloses the detector component, reducing frictional wear and environmental exposure, and utilizing a reed switch and magnetic field detection for contactless position sensing, allowing for easy installation and retrospective fitting without major re-design of existing components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a cam mechanism is used for lock detection, then the position of the push rod can be detected, but the manufacturing complexity increases and service life decreases due to wear and tight tolerances

Engineering Contradiction:

Improvelock state detectionVSAvoidcam mechanism complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical cam mechanism with a magnetic field-based detection system. A magnet is attached to the push rod, and a reed switch is mounted on the housing to detect the magnet's position. This substitution eliminates mechanical contact and wear between detection components, reducing complexity and maintenance while maintaining detection functionality.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces a magnet as an intermediary element that mediates between the push rod position and the reed switch detection. The magnet creates a magnetic field that actuates the reed switch without requiring direct mechanical contact, thereby eliminating wear and reducing manufacturing tolerances while enabling reliable position detection.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Measurement precision

If a cam mechanism is used for lock detection, then the position of the push rod can be detected, but the manufacturing cost increases due to tight tolerances

Engineering Contradiction:

Improvelock state detectionVSAvoidmanufacturing cost

Core Design Contradiction:

Measurement precisionVSEase of manufacture

Solution Approach 1:

The patent replaces the mechanical cam mechanism with a magnetic field-based detection system. A magnet is attached to the push rod, and a reed switch is mounted on the housing to detect the magnet's position. This substitution eliminates mechanical contact and wear, reducing manufacturing complexity and cost while maintaining detection functionality.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces a magnet as an intermediary element that mediates between the push rod position and the reed switch detection. The magnet creates a magnetic field that actuates the reed switch without requiring direct mechanical contact, thereby eliminating wear and reducing manufacturing tolerances while enabling reliable position detection.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Device complexity

If the detector component is exposed to the environment, then the structure is simple, but the service life is reduced due to frictional wear and environmental exposure

Engineering Contradiction:

Improvedetector housing structureVSAvoiddetector service life

Core Design Contradiction:

Device complexityVSDuration of action of stationary object

Solution Approach 1:

The patent uses a protective housing or enclosure that surrounds the detector components, particularly the reed switch and magnet assembly. This housing acts as a protective shell that shields the sensitive components from environmental factors such as dust, moisture, and physical damage, thereby extending service life without significantly increasing structural complexity.

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The patent introduces a magnet as an intermediary element that mediates between the push rod position and the reed switch detection. The magnet creates a magnetic field that actuates the reed switch without requiring direct mechanical contact, thereby eliminating wear and reducing manufacturing tolerances while enabling reliable position detection.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 solution provides a differential lock actuator with extended service life and simplified maintenance, as the detector components are protected from wear and environmental influences, enabling reliable lock state detection with reduced complexity and cost.

Implementation Method 1

A differential lock actuator with a removable cap housing that encloses the detector component, reducing frictional wear and environmental exposure, and utilizing a reed switch and magnetic field detection for contactless position sensing

Methodology Applied

Scientific EffectMagnetic field detection: Magnetic Field

Data Source

PatentEP3156695B1Differential lock actuator

Publication Date: 2020.09.16 MERITOR HEAVY VEHICLE SYST CAMERI

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AI summary

The present invention relates to a differential lock actuator (1) with a lock detection assembly. The differential lock actuator (1) comprises a housing (10), a push rod (20) configured to be movable within the housing (10) between a first position and a second position for activation/deactivation of a differential locking system and a lock detection assembly adapted to detect a position of the push rod (20) within the housing (10), wherein the lock detection assembly comprises a first detector component (70) connected to a removable part (30) of the housing (10).