Switching Unit Positioning Tab for Circuit Breaker Assembly

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing electrical switching devices face challenges in achieving precise positioning of the switching unit within the device due to tolerance chains, leading to high manufacturing costs and complex assembly processes.

Innovation Solution

The introduction of a positioning tab on the lock plate allows direct positioning of the switching unit within the housing, eliminating long tolerance chains and enabling precise mechanical alignment, which is cost-effective and simplifies the assembly process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If positioning is done via tolerance chains using multiple stops and assembly aids, then the switching unit can be assembled, but positioning precision deteriorates and manufacturing costs increase

Engineering Contradiction:
Improvepositioning precisionVSAvoidassembly complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent extracts the positioning function from the complex tolerance chain system and concentrates it into a single integrated positioning element (the positioning tab on the lock plate). This eliminates the need for multiple separate stops and assembly aids, achieving precise positioning while simplifying the overall assembly structure.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The positioning tab is designed as a distinct segment of the lock plate that performs the positioning function independently. This segmentation allows the positioning feature to be designed, manufactured, and assembled separately with simplified tolerances, while the rest of the switching unit maintains its functional requirements.

Inventive Principle:
Principle #1Segmentation

2Manufacturing precision

If narrow tolerance specifications are applied to individual components, then positioning precision improves, but manufacturing costs increase

Engineering Contradiction:
Improvepositioning precisionVSAvoidmanufacturing cost
Core Design Contradiction:
Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The patent extracts the positioning function into a dedicated positioning tab that serves as the primary reference feature. This allows the majority of components to be manufactured with standard, more economical tolerances, while only the positioning tab and its mating feature require tight tolerances for precise positioning.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The positioning tab is designed to establish the correct position of the switching unit before other components are assembled. This preliminary positioning action ensures that subsequent assemblies occur at pre-defined locations, eliminating the need for tight tolerances across all components and reducing overall manufacturing costs.

Inventive Principle:
Principle #10Preliminary action

3Manufacturing precision

If subsequent deformation of lock plate parts is performed to improve positioning accuracy, then positioning precision improves, but manufacturing time and cost increase

Engineering Contradiction:
Improvepositioning precisionVSAvoidmanufacturing efficiency
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

The positioning tab is designed with built-in positioning features (such as tapered surfaces, elastic deformation capabilities, or self-centering geometries) that automatically achieve precise positioning during the normal assembly process. This eliminates the need for subsequent deformation operations after assembly, as the positioning is accomplished in a single assembly action.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The positioning tab is designed to self-position the switching unit during assembly through its geometric features. The tab may incorporate elastic elements that deform during insertion and then spring back to establish precise positioning, or tapered surfaces that self-align during insertion. This self-positioning mechanism eliminates the need for additional adjustment or deformation steps.

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP2626880B1Switching unit for an electric switching device
Publication Date: 2016.04.13 SIEMENS AG
  • EP2626880B1 patent drawingFigure 1a~1b
  • EP2626880B1 patent drawingFigure 2
  • EP2626880B1 patent drawingFigure 3

AI summary

The present invention relates to a switching unit (10) for an electrical switching device (100), in particular for an electrical circuit breaker, comprising a switching lock (20) with a switching lever (22) and a switching mechanism (24) that can be actuated by the switching lever (22), further comprising at least one lock plate (30) to which the switching lock (20) is attached, wherein the at least one lock plate (30) has at least one positioning tab (32) which is designed for positioning the switching unit (10) in a housing (110) of the electrical switching device (100).