Magnetic Security Switch Using a Field-Gradient Suspended Object

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Security switches that utilize induced magnetic fields in reeds to detect magnets are limited by the inverse-square law, requiring a short distance between the magnet and reed for effective polarization, restricting their applications and necessitating a magnet on the door.

Innovation Solution

A proximity sensor system that employs a magnetic field source to produce a magnetic field gradient, allowing a magnetically susceptible object to shift positions based on the actuator's proximity, enabling detection from a longer distance through a circuit that detects the object's position.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a magnet and reed configuration is used for security switch detection, then the magnetic field can polarize the reed to close an electrical circuit, but the detection distance is limited to a short range due to the inverse-square law

Engineering Contradiction:

Improvedetection distanceVSAvoidmagnetic field strength

Core Design Contradiction:

Measurement precisionVSForce

Solution Approach 1:

The patent introduces a magnetically susceptible object as an intermediary between the magnetic field source and the reed switch. This object is suspended by magnetic forces from the source and can be actuated by external magnets to change position, thereby mediating the detection process and enabling longer detection distances without requiring strong direct magnetic fields between the external magnet and reed switch

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces the direct magnetic field interaction system with a mechanical suspension system. The magnetically susceptible object is suspended by magnetic forces but actuated mechanically through position changes, allowing the system to detect magnets at longer distances while maintaining reliable circuit closure through the reed switch

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Adaptability or versatility

If a magnet is attached to the door for security switch operation, then the reed can be polarized effectively, but the application scope is restricted and requires modification of the door structure

Engineering Contradiction:

Improveapplication scopeVSAvoidinstallation complexity

Core Design Contradiction:

Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The patent inverts the traditional configuration by placing the magnetic field source and magnetically susceptible object in the security switch assembly rather than attaching a magnet to the door. This inversion allows the security switch to be self-contained and eliminates the need for door modifications, significantly improving adaptability and ease of installation

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent creates a universal security switch design that can be applied to various door types and configurations without requiring specific modifications. The self-contained magnetic field source and susceptible object assembly can detect magnets on any door surface, making the system highly adaptable to different applications while simplifying installation

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

Enables security switches to detect actuators from a greater distance, expanding their application range and eliminating the need for a magnet on the door, while maintaining reliable signal detection.

Implementation Method 1

The magnetic field source is configured to produce a magnetic field gradient. The magnetically susceptible object is suspended at a first position at least in part due to the magnetic field gradient and shiftable to a second position when the actuator affects the magnetic field gradient.

Methodology Applied

Scientific EffectMagnetic field gradient: Magnetic Field

Implementation Method 2

The magnet emits a magnetic field, and when the magnet is within a threshold distance to a reed, the magnetic field of the magnet polarizes the reed.

Methodology Applied

Scientific EffectMagnetic polarization: Magnetism

Implementation Method 3

The polarization of the reed causes a contacting device to close an electrical circuit, which sends a signal indicative of the proximity of the magnet.

Methodology Applied

Scientific EffectElectrical conduction: Conduction (electrical)

Data Source

PatentUS11990298B2Magnetic proximity sensor, security switch, and method of detecting an actuator

Publication Date: 2024.05.21 MAGNASPHERE CORP

AI summary

A security switch for detecting an actuator comprises a magnetic field source, a magnetically susceptible object, and a circuit. The magnetic field source is configured to produce a magnetic field gradient. The magnetically susceptible object is suspended at a first position at least in part due to the magnetic field gradient and shiftable to a second position when the actuator affects the magnetic field gradient. The circuit is configured to detect when the object is in the second position.