High Power Fuse Terminal with Scalable U-Shaped Clamping

Solution Overview

Problem

High-power automotive fuses face limitations in current-carrying capacity due to copper terminals' susceptibility to relaxation at elevated temperatures, leading to reduced conductivity and increased resistance, which restricts the size and performance of electrical connectors.

Innovation Solution

A scalable terminal design utilizing opposing beams and U-shaped clamping members made of different metallic compositions, where the beams are made of a high-conductivity material like copper and the clamping members are made of a material with a higher relaxation temperature, such as stainless steel, to maintain compression force and contact area at elevated temperatures.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If copper terminals are used for high conductivity, then electrical conductivity is improved, but relaxation at elevated temperatures increases leading to reduced clamping force

Engineering Contradiction:

Improveelectrical conductivityVSAvoidclamping force stability

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

The terminal is divided into two distinct functional segments: copper legs for current conduction and a separate stainless steel clamping member for maintaining contact force. This segmentation allows each material to optimize its specific function without compromise.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The terminal assembly uses a composite structure combining copper (high conductivity) and stainless steel (high temperature stability) materials. The copper legs provide excellent electrical conductivity while the stainless steel clamping member provides stable mechanical force at elevated temperatures.

Inventive Principle:

Principle #40Composite materials

2Force

If terminal thickness and width are increased to improve spring force, then clamping force is improved, but the overall size of the fuse increases

Engineering Contradiction:

Improvespring forceVSAvoidfuse size

Core Design Contradiction:

ForceVSVolume of moving object

Solution Approach 1:

The invention changes the material parameter (using stainless steel with higher modulus of elasticity and lower relaxation) of the clamping member to achieve higher spring force without increasing the physical dimensions of the terminal.

Inventive Principle:

Principle #35Parameter changes

3Stability of the object's composition

If copper alloys are used to reduce relaxation, then relaxation resistance is improved, but conductivity decreases leading to reduced current capacity

Engineering Contradiction:

Improverelaxation resistanceVSAvoidcurrent carrying capacity

Core Design Contradiction:

Stability of the object's compositionVSReliability

Solution Approach 1:

The terminal is divided into two distinct functional segments: copper legs for current conduction and a separate stainless steel clamping member for maintaining contact force. This segmentation allows each material to optimize its specific function without compromise.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The terminal assembly uses a composite structure combining copper (high conductivity) and stainless steel (high temperature stability) materials. The copper legs provide excellent electrical conductivity while the stainless steel clamping member provides stable mechanical force at elevated temperatures.

Inventive Principle:

Principle #40Composite materials

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 enhances the current-carrying capacity of fuses and connectors, allowing for higher amp ratings while maintaining low resistance and conductivity, enabling fuses to handle up to 80-100 amps with a standard footprint, and providing increased stability and normal forces on terminal receptors.

Implementation Method 1

U-shaped clamping members made of different metallic compositions... for applying a predetermined compression force

Methodology Applied

Scientific EffectCompression: Compression

Implementation Method 2

The opposing beams spreads apart to receive the blade terminal... applying a predetermined compression force

Methodology Applied

Scientific EffectElasticity: Elasticity

Implementation Method 3

Copper has good electrical conductivity properties, and has been a preferred material for the terminals

Methodology Applied

Scientific EffectElectrical conduction: Conduction (electrical)

Implementation Method 4

copper is susceptible to relaxation (i.e., loss of spring force) as the temperature increases... copper alloys for which relaxation does not occur until higher temperatures are reached

Methodology Applied

Scientific EffectThermal relaxation: Stress Relaxation

Data Source

PatentUS7892050B2High power fuse terminal with scalability

Publication Date: 2011.02.22 LEAR CORP

AI summary

A female terminal receptor for an automotive fuse or a terminal includes three or more pairs of opposing beams and at least one U-shaped clamping member. The U-shaped clamping member has a first base portion laterally disposed between two pairs of opposing beams and at least one pair of first end portions disposed over at least one pair of opposing beams for applying a predetermined compression force. The opposing beams have a first metallic composition and the U-shaped clamping member has a second metallic composition, wherein the first metallic composition has a higher conductivity than the second metallic composition, and wherein the second metallic composition has a higher relaxation temperature than the first metallic composition.