Welded Coaxial Wire Contact for RF Impedance Matching

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing wire connector assemblies for coaxial cables, particularly in automotive applications, face challenges with mechanical adherence methods like crimping and soldering, which require orientation and can introduce impedance mismatches affecting RF performance.

Innovation Solution

A wire assembly with a contact welded to the tip of the inner conductor, eliminating the need for crimping or soldering, where the contact is non-oriented and can be securely attached with percussion welding, reducing the length of dielectric insulator stripping and minimizing impedance mismatches.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If crimping or soldering is used to attach the contact to the inner conductor, then mechanical connection is achieved, but orientation requirements and impedance mismatches occur

Engineering Contradiction:
Improvemechanical connection strengthVSAvoidimpedance matching
Core Design Contradiction:
StrengthVSManufacturing precision

Solution Approach 1:

The patent replaces the mechanical crimping system with a welding system. Instead of using mechanical force to deform the contact and inner conductor together, the invention uses welding to create a direct metallurgical bond between the contact tip and the exposed inner conductor tip, eliminating the need for mechanical deformation and associated orientation requirements.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the attachment method parameter from mechanical (crimping force, deformation) to thermal/electrical (welding current, temperature). This parameter change allows for a more precise control of the joint formation process, reducing impedance mismatches caused by mechanical deformation and improving RF performance.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If crimping is used to attach the contact to the inner conductor, then electrical connection is achieved, but contact orientation is required during assembly

Engineering Contradiction:
Improveelectrical connection reliabilityVSAvoidassembly orientation requirement
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The patent replaces the mechanical crimping system with a welding system. Instead of using mechanical force to deform the contact and inner conductor together, the invention uses welding to create a direct metallurgical bond between the contact tip and the exposed inner conductor tip, eliminating the need for mechanical deformation and associated orientation requirements.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent inverts the traditional approach by exposing the tip of the inner conductor and welding the contact to it, rather than inserting the inner conductor into the contact and crimping. This inversion allows the contact to be attached in any orientation, simplifying the assembly process.

Inventive Principle:
Principle #13The other way round (Inversion)

3Ease of manufacture

If longer length of dielectric insulator is stripped for crimping, then contact attachment is achieved, but impedance mismatches increase

Engineering Contradiction:
Improvecontact attachment feasibilityVSAvoidimpedance matching
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent replaces the mechanical crimping system with a welding system. Instead of using mechanical force to deform the contact and inner conductor together, the invention uses welding to create a direct metallurgical bond between the contact tip and the exposed inner conductor tip, eliminating the need for mechanical deformation and associated orientation requirements.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent performs preliminary exposure of the inner conductor tip before the welding operation. By exposing only the necessary length of the inner conductor tip and then immediately welding the contact to it, the invention prevents the need for longer insulator stripping that would occur with crimping, thereby maintaining impedance matching.

Inventive Principle:
Principle #10Preliminary action

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 solution enhances RF performance by reducing impedance mismatches and allows for a more reliable, low-cost, and automated manufacturing process with improved mechanical strength and ease of assembly.

Implementation Method 1

The contact is welded to the tip of the inner conductor at the first end

Methodology Applied
Scientific EffectWelding: Welding

Data Source

PatentEP4312312A1Wire assembly with welded contact
Publication Date: 2024.01.31 APTIV TECHNOLOGIES AG
  • EP4312312A1 patent drawingFigure 1A~1B
  • EP4312312A1 patent drawingFigure 2A
  • EP4312312A1 patent drawingFigure 2B~2C

AI summary

A wire assembly includes a cable and a contact. The wire includes at least an inner conductor and an insulating jacket surrounding the inner conductor, wherein a tip of the inner conductor is exposed at a first end. The contact is welded to the tip of the inner conductor at the first end.