Lorentz Force Contact Mechanism for Electromagnetic Contactor

Solution Overview

Problem

Existing electromagnetic contactors face challenges in preventing the movable contact from opening due to electromagnetic repulsion when a large current is applied, requiring increased spring force and larger configurations to manage this repulsion effectively.

Innovation Solution

The contact mechanism shapes either the fixed or movable contact to generate a Lorentz force that counteracts the electromagnetic repulsion, using L-shaped or U-shaped conductive plate configurations to prevent the movable contact from opening, thereby reducing the need for increased spring force and maintaining a compact design.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the spring force of the contact spring is increased to prevent electromagnetic repulsion from opening the movable contact, then the contact pressure is improved, but the device complexity and size increase

Engineering Contradiction:

Improvecontact pressureVSAvoiddevice complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical spring force system with an electromagnetic field system. By shaping the fixed contact into a U-shape and positioning the movable contact within it, the patent uses electromagnetic repulsion between the contacts to maintain contact pressure, eliminating the need for mechanical springs and their associated thrust generation mechanisms.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the geometric parameters of the contact structure by forming the fixed contact into a U-shape with specific dimensions (width W1, depth D1) and positioning the movable contact with specific dimensions (width W2, depth D2) at a predetermined distance. This geometric configuration optimization enables the electromagnetic field to provide the necessary contact pressure without mechanical springs.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If the spring force of the contact spring is increased to prevent electromagnetic repulsion from opening the movable contact, then the contact pressure is improved, but the electromagnetic contactor size increases

Engineering Contradiction:

Improvecontact pressureVSAvoidelectromagnetic contactor size

Core Design Contradiction:

ReliabilityVSVolume of moving object

Solution Approach 1:

The patent replaces the mechanical spring force system with an electromagnetic field system. By shaping the fixed contact into a U-shape and positioning the movable contact within it, the patent uses electromagnetic repulsion between the contacts to maintain contact pressure, eliminating the need for mechanical springs and their associated thrust generation mechanisms.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the geometric parameters of the contact structure by forming the fixed contact into a U-shape with specific dimensions (width W1, depth D1) and positioning the movable contact with specific dimensions (width W2, depth D2) at a predetermined distance. This geometric configuration optimization enables the electromagnetic field to provide the necessary contact pressure without mechanical springs.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If the thrust generated by the electromagnet is increased to ensure contact pressure, then the contact reliability is improved, but the device complexity and size increase

Engineering Contradiction:

Improvecontact pressureVSAvoiddevice complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical spring force system with an electromagnetic field system. By shaping the fixed contact into a U-shape and positioning the movable contact within it, the patent uses electromagnetic repulsion between the contacts to maintain contact pressure, eliminating the need for mechanical springs and their associated thrust generation mechanisms.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the geometric parameters of the contact structure by forming the fixed contact into a U-shape with specific dimensions (width W1, depth D1) and positioning the movable contact with specific dimensions (width W2, depth D2) at a predetermined distance. This geometric configuration optimization enables the electromagnetic field to provide the necessary contact pressure without mechanical springs.

Inventive Principle:

Principle #35Parameter changes

4Reliability

If the thrust generated by the electromagnet is increased to ensure contact pressure, then the contact reliability is improved, but the electromagnetic contactor size increases

Engineering Contradiction:

Improvecontact pressureVSAvoidelectromagnetic contactor size

Core Design Contradiction:

ReliabilityVSVolume of moving object

Solution Approach 1:

The patent replaces the mechanical spring force system with an electromagnetic field system. By shaping the fixed contact into a U-shape and positioning the movable contact within it, the patent uses electromagnetic repulsion between the contacts to maintain contact pressure, eliminating the need for mechanical springs and their associated thrust generation mechanisms.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the geometric parameters of the contact structure by forming the fixed contact into a U-shape with specific dimensions (width W1, depth D1) and positioning the movable contact with specific dimensions (width W2, depth D2) at a predetermined distance. This geometric configuration optimization enables the electromagnetic field to provide the necessary contact pressure without mechanical springs.

Inventive Principle:

Principle #35Parameter changes

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 effectively prevents the movable contact from opening under large currents without mechanical pressure, reducing the thrust required from the electromagnet and maintaining a smaller electromagnetic contactor size.

Implementation Method 1

at least either the fixed contact or the movable contact is shaped so as to increase a Lorentz force that acts against an electromagnetic repulsion in an opening direction, which is generated between the fixed contact and the movable contact upon application of a current

Methodology Applied

Scientific EffectLorentz force: Lorentz Force

Data Source

PatentUS8981883B2Contact mechanism and electromagnetic contactor using same

Publication Date: 2015.03.17 FUJI ELECTRIC FA COMPONENTS & SYST CO LTD

AI summary

A contact mechanism is capable of, without enlarging the entire configuration thereof, preventing the generation of an electromagnetic repulsion that opens a movable contact upon application of a current, and also provides an electromagnetic contactor that uses this contact mechanism. A contact mechanism has a fixed contact and a movable contact that are inserted in a current-carrying path. In the contact mechanism, the fixed contact or the movable contact is formed into an L-shape or a U-shape so as to generate a Lorentz force that acts against an electromagnetic repulsion in an opening direction, which is generated between the fixed contact and the movable contact upon application of a current.