Thermoplastic Sandwich Panel Living Hinge Formation

Solution Overview

Problem

Existing methods for manufacturing sandwich-type composite panels with living hinges require additional processing steps and materials, leading to increased manufacturing time, cost, and potential quality defects due to separate hinge components.

Innovation Solution

A method involving a stack of reinforced thermoplastic skins and a thermoplastic cellular core, where the skins are heated and pressed in a mold with a protrusion to crush and locally compact the core, forming a living hinge without additional post-processing steps, with the first skin stretching to create a strong and integrated hinge.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If separate hinges are fixed to sandwich-structure composite panels after panel formation, then the panels can be hinged to other panels, but this requires additional workstations and increases manufacturing time and cost

Engineering Contradiction:

Improvehinge functionalityVSAvoidmanufacturing time

Core Design Contradiction:

Adaptability or versatilityVSProductivity

Solution Approach 1:

The hinge functionality is merged into the panel structure itself by creating an integrated living hinge during the panel formation process. The skin is designed with a hinge line that allows the panel to be formed in one piece, eliminating the need for separate hinge components and post-assembly operations. This combines the panel and hinge into a single integrated structure.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The hinge line is prepared in advance during the panel formation process. The skin is positioned and formed with the hinge line already in place before final bonding occurs. This preliminary preparation of the hinge line allows for seamless integration without requiring additional workstations or post-assembly steps.

Inventive Principle:

Principle #10Preliminary action

2Adaptability or versatility

If separate hinges are fixed to sandwich-structure composite panels, then hinge functionality is achieved, but this adds to the cost of making such panels

Engineering Contradiction:

Improvehinge functionalityVSAvoidmanufacturing cost

Core Design Contradiction:

Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The hinge functionality is merged into the panel structure itself by creating an integrated living hinge during the panel formation process. The skin is designed with a hinge line that allows the panel to be formed in one piece, eliminating the need for separate hinge components and post-assembly operations. This combines the panel and hinge into a single integrated structure.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The panel structure itself provides the hinge functionality through its own skin and core construction. The living hinge is formed from the panel's own materials (skin and core) without requiring external hinge components. This self-service approach eliminates the need for additional parts and reduces manufacturing complexity.

Inventive Principle:

Principle #25Self-service

3Adaptability or versatility

If separate external parts are mounted on composite panels, then hinge functionality is achieved, but this is a source of quality defects

Engineering Contradiction:

Improvehinge functionalityVSAvoidquality defects

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The hinge functionality is merged into the panel structure itself by creating an integrated living hinge during the panel formation process. The skin is designed with a hinge line that allows the panel to be formed in one piece, eliminating the need for separate hinge components and post-assembly operations. This combines the panel and hinge into a single integrated structure.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The panel structure itself provides the hinge functionality through its own skin and core construction. The living hinge is formed from the panel's own materials (skin and core) without requiring external hinge components. This self-service approach eliminates the need for additional parts and reduces manufacturing complexity.

Inventive Principle:

Principle #25Self-service

4Adaptability or versatility

If living hinges are made by cutting through skins after panel formation, then hinges are created, but the hinges may not be strong enough during extended use

Engineering Contradiction:

Improvehinge functionalityVSAvoidhinge strength

Core Design Contradiction:

Adaptability or versatilityVSStrength

Solution Approach 1:

The hinge line is prepared in advance during the panel formation process. The skin is positioned and formed with the hinge line already in place before final bonding occurs. This preliminary preparation of the hinge line allows for seamless integration without requiring additional workstations or post-assembly steps.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The living hinge is constructed using composite materials - the skin layer combined with the compacted core material. This composite construction provides both flexibility for hinging and sufficient strength for extended use. The bonding between skin and core at the hinge line creates a reinforced structure that maintains strength while allowing movement.

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 method enables the production of lightweight, strong sandwich-type composite panels with integrated living hinges, reducing manufacturing time and costs while ensuring the hinges function properly during extended use without additional materials or steps.

Implementation Method 1

heating the skins to a softening temperature wherein the first skin is stretchable when heated to the softening temperature

Methodology Applied

Scientific EffectThermal softening: Heating

Implementation Method 2

applying a pressure to the stack after the step of heating to form the composite panel

Methodology Applied

Scientific EffectCompression bonding: Compression

Implementation Method 3

crushing a portion of the composite panel at a predetermined location simultaneously with the step of applying to locally compact and separate the cellular core

Methodology Applied

Scientific EffectLocal compaction: Compression

Implementation Method 4

The first skin stretches during the step of crushing while remaining intact between the two side portions. The first and second skins are bonded together at the predetermined location to form the living hinge

Methodology Applied

Scientific EffectThermal bonding: Heating

Data Source

PatentUSRE46104E1Method of making a sandwich-type composite panel having a living hinge and panel obtained by performing the method

Publication Date: 2016.08.16 GLOBAL IP HLDG LLC

AI summary

A method of making a sandwich-type composite panel having a living hinge from a stack of material is provided. The stack includes first and second reinforced thermoplastic skins heated to a softening temperature and a thermoplastic cellular core disposed between the skins. The first skin is stretchable when heated to the softening temperature. A pressure is applied to the stack after the step of heating to form the composite panel. A portion of the composite panel is crushed at a predetermined location simultaneously with the step of applying to locally compact and separate the cellular core at the predetermined location to form two side portions of the panel and a crushed portion of the panel between the two side portions. The first skin stretches during the step of crushing while remaining intact between the two side portions. The skins bond together at the predetermined location to form the living hinge.