DC Relay Arc Path Formation Using Offset Magnet Arrangement

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing DC relays face challenges in controlling the direction of an arc discharge path, leading to potential damage to internal components and user inconvenience due to the dependence on current flow direction, as well as limitations in forming an effective arc discharge path and extinguishing the arc efficiently.

Innovation Solution

An arc path formation unit with a magnet frame and strategically arranged magnets that generate a magnetic field to direct the arc away from the center region, allowing the arc to be extinguished externally, regardless of current direction, and enhancing the magnetic field strength for effective arc path formation without structural changes.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If magnets are provided to form an arc discharge path, then the arc can be discharged through a preset path, but the arc may move toward the center region and damage internal members when current flows in certain directions

Engineering Contradiction:

Improvearc discharge path controlVSAvoidarc damage to internal members

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The relay body is divided into a center region and a side region, with the arc discharge path directed toward the side region. This segmentation isolates the arc from the center region where shaft and spring members are located, preventing arc damage to these internal components while maintaining effective arc discharge.

Inventive Principle:

Principle #1Segmentation

2Reliability

If the electromagnetic force direction depends on current flow direction, then the arc discharge path can be controlled, but the user must consider current direction which causes inconvenience

Engineering Contradiction:

Improvearc discharge path controlVSAvoiduser convenience

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

Instead of relying on electromagnetic force direction that changes with current flow direction, the patent uses permanent magnets to generate a fixed magnetic field that always directs the arc toward the side region. This inversion of the control mechanism eliminates the need for users to consider current direction, making the relay bidirectional and more convenient to operate.

Inventive Principle:

Principle #13The other way round (Inversion)

3Object-affected harmful factors

If magnets are arranged to direct arc away from center region, then internal members are protected from arc damage, but the magnetic field strength may be insufficient for effective arc path formation

Engineering Contradiction:

Improvearc damage preventionVSAvoidmagnetic field strength

Core Design Contradiction:

Object-affected harmful factorsVSForce

Solution Approach 1:

Multiple permanent magnets are arranged in specific configurations (first and second permanent magnets on opposite sides, third permanent magnets at corners) to combine their magnetic fields. This merging of magnetic fields creates a sufficiently strong and uniform magnetic field in the side region to effectively guide and extinguish the arc, while maintaining the arc's diversion away from the center region to protect internal members.

Inventive Principle:

Principle #5Merging (Combining)

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 effectively directs the arc away from critical components, preventing damage and ensuring efficient arc extinguishing, while allowing for flexible arc path direction without altering the relay's structure, thus improving user convenience and reliability.

Implementation Method 1

magnets coupled to the plurality of surfaces to form magnetic fields in the inner space

Methodology Applied

Scientific EffectMagnetic field: Magnetic Field

Implementation Method 2

The arc discharge path may be formed by the formed magnetic fields and electromagnetic force generated by a flow of current

Methodology Applied

Scientific EffectElectromagnetic force: Lorentz Force

Implementation Method 3

According to the Fleming's left hand rule, electromagnetic force is formed outward as indicated with a hatched arrow. Accordingly, a generated arc can be discharged to outside along the direction of the electromagnetic force

Methodology Applied

Scientific EffectElectromagnetic force: Lorentz Force

Data Source

PatentUS11842870B2Arc path formation unit and direct current relay including same

Publication Date: 2023.12.12 LS ELECTRIC CO LTD

AI summary

Disclosed are an arc path formation unit and a direct current relay including same. An arc path formation unit according to an embodiment of the present disclosure comprises a plurality of magnet parts. One of the plurality of magnet parts is disposed on one surface of a magnet frame. The remaining magnet parts among the plurality of magnet parts are disposed on the other respective surfaces of the magnet frame. The magnet part disposed on the one surface is formed longer than the other magnet parts. Also, the magnet parts disposed on the other surface are spaced apart from each other as far as possible. Accordingly, the magnetic field formed between the magnet parts is formed such that the electromagnetic force generated in each of stationary contacts is generated in a direction away from the central region. As a result, damage to components disposed in the central region can be prevented.