Z-Shaped Axle Test Assembly for Circuit Breaker Space Reduction

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Solution Overview

Problem

Conventional circuit breakers with leaf spring contacts for testing ground fault and arc fault circuitry face space constraints and high manufacturing costs due to the need for external linkage, which complicates the testing mechanism.

Innovation Solution

A test assembly featuring a z-shaped axle that secures the main spring on the MCB pole side, acting as a conductor to initiate a trip operation when actuated, allowing for reduced space usage and lower manufacturing costs by eliminating the need for external linkages.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If leaf spring contacts are used for testing ground fault and arc fault circuitry, then the testing functionality is achieved, but the space requirements and manufacturing costs increase due to the need for external linkage

Engineering Contradiction:
Improvetesting functionalityVSAvoidspace requirements
Core Design Contradiction:
ReliabilityVSArea of stationary object

Solution Approach 1:

The axle serves dual functions: it mechanically connects the test button to the spring contact while simultaneously acting as an electrical conductor for the test signal. This merging of mechanical and electrical functions eliminates the need for separate external linkages, reducing space requirements while maintaining testing functionality.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The axle is designed as a multi-functional component that performs both mechanical linkage and electrical conduction. By making the structural component also serve as the electrical pathway, the design eliminates redundant parts and reduces the overall space needed for the testing mechanism.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Reliability

If leaf spring contacts with external linkage are used, then the testing mechanism is complete, but the manufacturing costs increase

Engineering Contradiction:
Improvetesting mechanism completenessVSAvoidmanufacturing costs
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

By combining the mechanical linkage function and electrical conduction function into a single axle component, the number of parts that need to be manufactured and assembled is reduced. This simplifies the manufacturing process and lowers costs while maintaining a complete testing mechanism.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The axle serves itself by being both the structural element that transmits mechanical force and the electrical conductor that transmits the test signal. This self-service approach eliminates the need for separate components, reducing manufacturing complexity and cost.

Inventive Principle:
Principle #25Self-service

3Area of stationary object

If the circuit breaker is designed to minimize space, then the compactness is achieved, but the accommodation of testing components becomes constrained

Engineering Contradiction:
ImprovecompactnessVSAvoidtesting component accommodation
Core Design Contradiction:
Area of stationary objectVSAdaptability or versatility

Solution Approach 1:

The axle integrates mechanical and electrical functions within a single component, allowing the testing mechanism to be accommodated in minimal space. This merging enables the circuit breaker to maintain compactness while still providing complete testing functionality.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The multi-functional axle allows the compact design to accommodate testing components by making the existing structural elements serve dual purposes. This versatility is achieved without requiring additional space, as the axle already exists as part of the compact structure.

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

The test assembly effectively reduces space requirements and manufacturing costs while maintaining the functionality of the circuit breaker's tripping mechanism, enhancing operational efficiency and cost-effectiveness.

Implementation Method 1

the axle conducts an electrical signal to the spring, and the spring provides a test signal to the circuit board

Methodology Applied
Scientific EffectElectrical conduction: Conduction (electrical)

Data Source

PatentEP2242080B1Test assembly for a circuit breaker
Publication Date: 2013.09.18 GENERAL ELECTRIC CO
  • EP2242080B1 patent drawingFigure 1
  • EP2242080B1 patent drawingFigure 2
  • EP2242080B1 patent drawingFigure 3

AI summary

A test assembly (112) for a circuit breaker (100) with a single pole module (110) having first and second conduction paths electrically isolated from each other via an interior wall (111) of the module (110) and a circuit board (201). The test assembly (112) includes an axle (116) at an upper portion of the interior wall (111) and having a first end (116a) and a second end (116b) extending along opposite sides of the interior wall (111), a test actuation member (114) configured to be actuated, and a spring (115) in operable communication with the test actuation member (114) and in signal communication with the circuit board (201). The spring (115) contacts the test actuation member (114) and the first end (116a) of the axle (116) when the test actuation member (114) is actuated, the axle (116) conducts an electrical signal to the spring (115), and the spring (115) provides a test signal to the circuit board (201) initiating a test operation of the circuit breaker (100).