Laser-Joined Bus Bar With Selective Plating for Reliable Connections

Solution Overview

Problem

The existing bus bar designs require extensive plating over the entire surface to improve electrical connection reliability, leading to increased material usage and costs, as they are formed as a single member along the wiring pathway, necessitating costly masking and processing.

Innovation Solution

A bus bar design featuring consecutively arranged plate-shaped connection and conductive members made from conductive materials like copper and aluminum, connected by laser joining, where only the connection members are plated, reducing material usage and processing costs while maintaining electrical reliability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If plate processing is performed on the entirety of the bus bar to improve electrical connection reliability, then the electrical connection reliability is improved, but the used amount of plating material increases and cost increases

Engineering Contradiction:

Improveelectrical connection reliabilityVSAvoidused amount of plating material

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

The bus bar is divided into multiple members (first member, second member, third member) with distinct functions. Only the connection portions (first connection portion and second connection portion) that require electrical connection reliability are plated, while the intermediate portion is not plated. This segmentation allows selective plating application.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different parts of the bus bar have different surface treatments: the connection portions have plated surfaces for reliable electrical connection, while the intermediate portion has an unplated surface. This local differentiation applies plating only where electrical connection reliability is needed, reducing overall plating material usage.

Inventive Principle:

Principle #3Local quality

2Reliability

If plate processing is performed on the entirety of the bus bar to improve electrical connection reliability, then the electrical connection reliability is improved, but the cost increases

Engineering Contradiction:

Improveelectrical connection reliabilityVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The bus bar is divided into multiple members (first member, second member, third member) with distinct functions. Only the connection portions (first connection portion and second connection portion) that require electrical connection reliability are plated, while the intermediate portion is not plated. This segmentation allows selective plating application.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different parts of the bus bar have different surface treatments: the connection portions have plated surfaces for reliable electrical connection, while the intermediate portion has an unplated surface. This local differentiation applies plating only where electrical connection reliability is needed, reducing overall plating material usage and cost.

Inventive Principle:

Principle #3Local quality

3Quantity of substance

If masking work is performed to decrease the used amount of plating material, then the used amount of plating material decreases, but the cost increases due to additional masking work

Engineering Contradiction:

Improveused amount of plating materialVSAvoidmanufacturing cost

Core Design Contradiction:

Quantity of substanceVSEase of manufacture

Solution Approach 1:

The bus bar is divided into multiple members (first member, second member, third member) with distinct functions. Only the connection portions (first connection portion and second connection portion) that require electrical connection reliability are plated, while the intermediate portion is not plated. This segmentation allows selective plating application.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different parts of the bus bar have different surface treatments: the connection portions have plated surfaces for reliable electrical connection, while the intermediate portion has an unplated surface. This local differentiation applies plating only where electrical connection reliability is needed, reducing overall plating material usage and cost.

Inventive Principle:

Principle #3Local quality

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 design reduces manufacturing costs by eliminating the need for extensive plating and masking, while maintaining reliable electrical connections through targeted plating of connection members, allowing for efficient and cost-effective production of bus bars with adaptable wiring pathways.

Implementation Method 1

The plate-shaped members 9 are connected to one another by being laser joined

Methodology Applied

Scientific EffectLaser joining: Laser Beam Welding

Data Source

PatentEP4135119B1Bus bar

Publication Date: 2023.10.18 YAZAKI CORP

Figure 1~2
Figure 3
Figure 4~5

AI summary

A bus bar (1) includes members (9) made from a conductive material and consecutively arranged to form a plate shape defining a wiring pathway (7). The members (9) adjacent to each other are connected to each other by laser joining. The members (9) include a first connection member (11) arranged at one end of the wiring pathway (7) and having a first connection portion (17) for electrical input-output, and a conductive member (13) connected to the first connection member (11) in a state where connection surfaces (23, 25) of the first connection member (11) and the conductive member (13) located in a same plane are in contact with each other. In the members (9), only the first connection member (11) is plated.