3D Vacuum-Insulated Door Structure with Tooling Fixture Sealing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing refrigerator cabinet structures with vacuum insulated panels face challenges in maintaining consistent insulation thickness and efficient gas removal to create a hermetic seal, leading to potential heat transfer inefficiencies.

Innovation Solution

A continuous core insulation member with non-planar surfaces and a barrier film envelope is used to form a vacuum insulated panel, where a tooling fixture engages the surfaces to remove gas and hermetically seal the envelope, ensuring a consistent thickness and efficient insulation across the appliance door.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If a vacuum insulated panel is used for refrigerator cabinet structures, then insulation efficiency is improved, but manufacturing complexity increases due to challenges in maintaining consistent insulation thickness and creating hermetic seals

Engineering Contradiction:
Improveinsulation efficiencyVSAvoidmanufacturing complexity
Core Design Contradiction:
Loss of energyVSDevice complexity

Solution Approach 1:

The vacuum insulated panel is segmented into distinct functional layers: a core insulation member providing thermal insulation, a barrier film envelope creating the vacuum seal, and a tooling fixture system enabling manufacturing. This segmentation allows each component to be optimized independently while simplifying the overall manufacturing process.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The core insulation member is pre-formed with specific geometric features (protrusions and recesses) before being placed in the barrier film envelope. The tooling fixture is also prepared in advance with corresponding features that will automatically align and engage with the insulation member, eliminating the need for complex real-time alignment procedures during vacuum sealing.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If gas removal is performed to create hermetic seal, then insulation performance is improved, but manufacturing difficulty increases due to challenges in removing substantially all gas from between barrier film and core insulation member

Engineering Contradiction:
Improvehermetic seal qualityVSAvoidgas removal difficulty
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The barrier film envelope and tooling fixture incorporate curved and contoured surfaces that conform to the three-dimensional geometry of the core insulation member. This curvature allows the barrier film to wrap around and engage with all surfaces of the insulation member, including recesses and protrusions, enabling complete gas evacuation from all cavities and crevices during the vacuum process.

Inventive Principle:
Principle #14Spheroidality (Curvature)

Solution Approach 2:

The tooling fixture acts as an intermediary device between the barrier film envelope and the core insulation member during gas removal. It provides a structured pathway for gas evacuation and maintains proper spacing and alignment, making the gas removal process more controlled and efficient without requiring complex manufacturing procedures.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Loss of energy

If consistent insulation thickness is maintained, then heat transfer resistance is improved, but manufacturing precision requirements increase

Engineering Contradiction:
Improveheat transfer resistanceVSAvoidthickness consistency
Core Design Contradiction:
Loss of energyVSManufacturing precision

Solution Approach 1:

The core insulation member is manufactured as a single integral piece with controlled thickness variations built into its design, featuring protrusions and recesses that accommodate the barrier film envelope. This approach accepts and manages thickness variations through design rather than attempting to eliminate them through ultra-precise manufacturing, thereby reducing manufacturing precision requirements while maintaining effective insulation performance.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

Different regions of the core insulation member have different geometric characteristics (protrusions in some areas, recesses in others) that are locally optimized to work with the barrier film envelope. This local variation in geometry allows the barrier film to conform to the insulation member's surface while maintaining effective vacuum sealing and insulation across the entire panel, without requiring uniform thickness throughout.

Inventive Principle:
Principle #3Local quality

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 the insulation efficiency by maintaining a consistent thickness and minimizing heat transfer through the refrigerator door, while allowing for the integration of appliance modules and mechanical components.

Implementation Method 1

Substantially all of the air is removed from between the barrier film and the core insulation member such that the barrier film envelope engages the female engaging surfaces and the male engaging surfaces

Methodology Applied
Scientific EffectVacuum: Vacuum

Implementation Method 2

the core insulation member and the barrier film envelope together form a vacuum insulated panel

Methodology Applied
Scientific EffectThermal Insulation: Thermal Insulation

Data Source

PatentEP2910878B1Vacuum packaged 3D vacuum insulated door structure and method therefor using a tooling fixture
Publication Date: 2019.08.28 WHIRLPOOL CORP
  • EP2910878B1 patent drawingFigure 1
  • EP2910878B1 patent drawingFigure 2
  • EP2910878B1 patent drawingFigure 3

AI summary

A method for creating a vacuum insulated panel (34) including preforming a continuous insulation member (22) having male and female engaging surfaces (28, 26) and providing a barrier film envelope (30) having an opening. The insulation member (22) is disposed within the barrier film envelope (30) and a tooling fixture (90) presses the barrier film envelope (30) against the male and female engaging surfaces (28, 26) to remove gas (32) from between the barrier film envelope (30) and the male and female engaging surfaces (28, 26). Substantially all gas (32) is removed from within the barrier film envelope (30) so that the barrier film envelope (30) substantially conforms to the insulation member (22). The opening of the barrier film envelope (30) is hermetically sealed. The barrier film envelope (30) forms a continuous layer over the insulation member (22) to form a vacuum insulated panel (34). An appliance door (12) comprising said vacuum insulated panel (34).