Switch Device Bus Bar Projection Contact

Solution Overview

Problem

Existing medium voltage switchgear designs are costly and complex due to the use of intermediate connector elements between the switch knife and bus bar, which complicates the production and increases the number of components.

Innovation Solution

A switch device design where the switch knife operates directly against a projection integral to the bus bar, eliminating the need for intermediate connector elements, with features like lateral elevations and spring elements ensuring reliable contact and corrosion resistance, and using materials like Sn, Ni, Ag, or Au for enhanced performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If an intermediate connector element is used between the switch knife and bus bar, then the connection reliability is improved, but the device complexity and production cost increase

Engineering Contradiction:

Improveconnection reliabilityVSAvoidnumber of components

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The bus bar is designed with an integrated projection that directly contacts the switch knife, merging the bus bar and connector element into a single integrated component. This eliminates the intermediate connector element while maintaining reliable electrical contact through the projection's geometric design that ensures proper engagement with the switch knife.

Inventive Principle:

Principle #5Merging (Combining)

2Reliability

If an intermediate connector element is used between the switch knife and bus bar, then the connection reliability is improved, but the production cost increases

Engineering Contradiction:

Improveconnection reliabilityVSAvoidproduction cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The bus bar is designed with an integrated projection that directly contacts the switch knife, merging the bus bar and connector element into a single integrated component. This eliminates the intermediate connector element while maintaining reliable electrical contact through the projection's geometric design that ensures proper engagement with the switch knife.

Inventive Principle:

Principle #5Merging (Combining)

3Ease of manufacture

If the switch knife operates directly against the bus bar without intermediate connector, then the production cost is reduced, but the contact reliability may be compromised

Engineering Contradiction:

Improveproduction costVSAvoidcontact reliability

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The bus bar features a localized projection with specific geometric characteristics (reduced thickness/width compared to the main bus bar body) that creates an optimized contact surface. This local modification ensures reliable electrical contact between the bus bar and switch knife while maintaining cost-effective production through integration.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The projection extends in the longitudinal direction of the bus bar along its length, creating a distributed contact interface rather than a single point contact. This dimensional extension ensures reliable electrical connection while simplifying the overall structure.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Data Source

PatentEP2347426B2A switch device and a switchgear provided therewith

Publication Date: 2016.09.07 ABB RES LTD

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AI summary

A switch device comprising a bus bar (10), and a switch knife (9), wherein the knife (9) is arranged so as to pivot around an axis perpendicular to a longitudinal axis of the bus bar (10). The bus bar (10) presents a projection (14) which is an integrated part of the bus bar (10), and the knife (9) is pivotable to a first position, in which it directly contacts said projection (14), and to a second position in which it is removed from contact with said projection (14).