Metal Foil Cable Shielding for EMI-Safe Connector Interfaces

Solution Overview

Problem

Cable assemblies often suffer from structural weakness and electromagnetic interference at the interface between cable and connector components, leading to desense issues in wireless communication devices.

Innovation Solution

A cable assembly design featuring a metal shell with a conformable metal foil and solder layer that provides double shielding and structural support, reducing noise and enhancing connectivity by sealing gaps and improving grounding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a cable assembly uses a simple interface between cable and connector components, then the device complexity is reduced, but the structural integrity and electromagnetic shielding are compromised

Engineering Contradiction:

Improveinterface structureVSAvoidstructural integrity

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The patent implements nested shielding structures where an inner metal shell is placed within an outer metal shell, and both are positioned within the connector housing. This nested arrangement provides multiple layers of protection without significantly increasing overall device complexity, as the structures are integrated into the existing connector architecture.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The patent combines multiple materials with different properties: metal shells for structural support and electromagnetic shielding, plastic for insulation and housing, and conductive materials for grounding. This composite material approach enhances structural integrity and shielding effectiveness while maintaining a manageable level of complexity through material selection rather than structural complexity.

Inventive Principle:

Principle #40Composite materials

2Device complexity

If a cable assembly uses a simple interface between cable and connector components, then the device complexity is reduced, but the electromagnetic shielding is compromised

Engineering Contradiction:

Improveinterface structureVSAvoidelectromagnetic interference

Core Design Contradiction:

Device complexityVSObject-affected harmful factors

Solution Approach 1:

The patent implements nested shielding structures where an inner metal shell is placed within an outer metal shell, and both are positioned within the connector housing. This nested arrangement provides multiple layers of protection without significantly increasing overall device complexity, as the structures are integrated into the existing connector architecture.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The patent addresses electromagnetic interference by converting potential harmful gaps and openings in the shielding structure into beneficial features through the use of conductive gaskets and overlapping shield configurations. These elements transform what could be sources of interference into effective shielding mechanisms that block EMI while maintaining a relatively simple overall structure.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Object-affected harmful factors

If the cable assembly uses extensive shielding structures, then the electromagnetic interference is reduced, but the structural integrity at the interface is not sufficiently improved

Engineering Contradiction:

Improveelectromagnetic interferenceVSAvoidstructural integrity

Core Design Contradiction:

Object-affected harmful factorsVSStrength

Solution Approach 1:

The patent combines multiple materials with different properties: metal shells for structural support and electromagnetic shielding, plastic for insulation and housing, and conductive materials for grounding. This composite material approach enhances structural integrity and shielding effectiveness while maintaining a manageable level of complexity through material selection rather than structural complexity.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The shielding structure is segmented into multiple functional components: an inner metal shell for primary shielding, an outer metal shell for additional protection and structural support, and conductive gaskets for sealing and grounding. This segmentation allows each component to be optimized for its specific function while collectively providing both enhanced structural integrity and effective EMI protection.

Inventive Principle:

Principle #1Segmentation

4Object-affected harmful factors

If a conformable metal foil is used to wrap around the metal shell, then the electromagnetic shielding is improved by covering all exterior surfaces, but the device complexity and manufacturing difficulty increase

Engineering Contradiction:

Improveelectromagnetic interferenceVSAvoidfoil wrapping process

Core Design Contradiction:

Object-affected harmful factorsVSEase of manufacture

Solution Approach 1:

The patent employs a flexible metal foil that can be wrapped around the metal shell components. This thin film approach provides comprehensive electromagnetic shielding coverage of all exterior surfaces while maintaining relative manufacturing simplicity, as the flexible nature of the foil allows it to conform to the shell geometry without requiring complex forming operations.

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

Instead of attempting to create rigid, pre-formed shields that would be difficult to manufacture, the patent inverts the approach by using a flexible foil that can be easily applied to the metal shells. This reversal of the manufacturing sequence - applying the shield after the shell is formed - significantly simplifies the manufacturing process while achieving complete shielding coverage.

Inventive Principle:

Principle #13The other way round (Inversion)

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

The solution effectively reduces electromagnetic interference, enhancing the performance of wireless communication devices by minimizing desense and improving structural integrity at the connector interfaces.

Implementation Method 1

a solder layer bonds and electrically couples: (i) the first foil portion to itself, (ii) the second foil portion to the shielding of the cable, and (iii) the third foil portion to the plug receiver

Methodology Applied

Scientific EffectSoldering: Soldering

Implementation Method 2

A cable assembly with an inner shell and metal foil... provides improved electromagnetic shielding... reduces the amount of desense-causing noise

Methodology Applied

Scientific EffectElectromagnetic shielding: Faraday Cage

Data Source

PatentEP3961817B1Cable shielding with metal foil

Publication Date: 2024.07.24 GOOGLE LLC

Figure 1
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Figure 3A~3B

AI summary

A cable assembly includes a plug receiver, a conductor interface, a metal shell encasing the conductor interface and a portion of a cable of the cable assembly, a metal foil that wraps conformably around an exterior of the metal shell, wherein the metal foil covers substantially all of the exterior of the metal shell and extends beyond the metal shell onto a cable shielding layer. The cable assembly further includes a solder layer disposed about the metal foil, wherein the solder layer bonds and electrically couples the first foil portion to itself, the second foil portion to cable shielding at the location on the plurality of conductors that is proximate to the conductor interface, and the third foil portion to the plug receiver. The cable assembly further includes an electrically insulating layer that encases the metal shell, the metal foil, and the solder layer.