Electronic Housing Interlocking via Molded Material

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Solution Overview

Problem

Portable electronic devices with metal housings face structural instability and RF performance issues due to metal blocking wireless transmission, and reducing metal to improve stability compromises structural integrity, especially during drop events.

Innovation Solution

A housing assembly with a metal portion acting as an RF antenna and a non-metal portion made of dual-state material, where micro-features in the metal portion engage with the non-metal material in a solid state to interlock and maintain RF performance while enhancing structural stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If metal housing parts are used to provide structural integrity, then strength is improved, but RF transmission is blocked

Engineering Contradiction:
Improvestructural integrityVSAvoidRF transmission blocking
Core Design Contradiction:
StrengthVSObject-generated harmful factors

Solution Approach 1:

The housing is divided into multiple metal parts separated by non-metal portions, creating RF transmission paths while maintaining structural integrity through distributed metal segments

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Metal material is strategically placed only in regions where structural strength is needed, while non-metal regions are positioned to allow RF transmission, creating local optimization of both properties

Inventive Principle:
Principle #3Local quality

2Object-generated harmful factors

If non-metal portions are added to enable RF transmission, then RF performance is improved, but structural stability deteriorates

Engineering Contradiction:
ImproveRF transmission blockingVSAvoidstructural stability
Core Design Contradiction:
Object-generated harmful factorsVSStability of the object's composition

Solution Approach 1:

Multiple housing parts are merged through interlocking mechanisms and adhesive bonding to create a unified structure that maintains stability while incorporating RF transmission paths

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The housing parts are connected through three-dimensional interlocking features including recesses, protrusions, and adhesive bonds distributed throughout the structure, providing multi-dimensional structural support

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Object-generated harmful factors

If metal housing parts are separated to allow RF transmission, then RF performance is improved, but structural strength deteriorates

Engineering Contradiction:
ImproveRF transmission blockingVSAvoidstructural strength
Core Design Contradiction:
Object-generated harmful factorsVSStrength

Solution Approach 1:

The housing combines metal parts for structural strength with non-metal portions for RF transmission, creating a composite structure that leverages the advantages of both material types

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

Interlocking features such as recesses and protrusions are pre-formed in the housing parts before assembly, enabling strong mechanical connections that maintain structural integrity while allowing RF transmission

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

The interlocking mechanism maintains RF performance by limiting metal to a well-defined region, improving structural integrity and resistance to external forces, such as those encountered during drops, without compromising antenna performance.

Implementation Method 1

a non-metal portion formed of a dual state material that is capable of transitioning between a liquid state and a solid state

Methodology Applied
Scientific EffectPhase transition: Phase Change

Data Source

PatentEP3420711B1Interlocking of housing parts of an electronic device
Publication Date: 2021.10.13 APPLE INC
  • EP3420711B1 patent drawingFigure 1~2
  • EP3420711B1 patent drawingFigure 3
  • EP3420711B1 patent drawingFigure 4

AI summary

An electronic device having multiple housing components interlocked together by a molded material is disclosed. In order to provide interlocking surfaces for the molded material, the housing components can include various geometries designed to receive and retain the molded material such that the housing components are secured with one another. For example, a first housing part can undergo several material removal operations to form multiple ribs, each with through holes. When the molded material extends along the ribs and into the through holes, the molded material cures and interlocks with the first housing part. A second housing part can include several stepped indentions that receive the molded material. Also, a third housing part can include a dovetail indention to receive the molded material such that the first and second housing parts interlock with the third housing part. The indentions can provide retention in three dimensions to protect against decoupling.