Internal Cover Joint Layout for Low-Leakage Isothermal Containers

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional isothermal containers experience heat leakage due to the inner box acting as a heat bridge, which compromises the ability to maintain stored items at a predetermined temperature for an extended period.

Innovation Solution

The isothermal container design incorporates a heat-insulating container with a core material, adsorbent, and cover materials, where the joined part of the cover materials is located inside a protection case, preventing direct contact with outside air and minimizing heat leakage. This design includes a phase change material on the bottom and wall portions of the container and lid, optimizing heat retention.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If the inner box is used as a structural component in conventional isothermal containers, then the structural integrity is improved, but heat leakage occurs due to the inner box acting as a heat bridge

Engineering Contradiction:
Improvestructural integrityVSAvoidheat leakage
Core Design Contradiction:
StrengthVSLoss of energy

Solution Approach 1:

The patent extracts the problematic inner box structure from the heat insulation system. Instead of having the inner box serve as both structural support and heat barrier, the invention separates these functions by using the inner box only for structural integrity while implementing a distinct vacuum insulation layer for thermal isolation, thereby eliminating the heat bridge effect

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent employs composite material structure by combining multiple insulation layers including vacuum space, reflective barriers, and insulating materials within the container wall structure. This multi-layer composite approach creates superior thermal resistance while maintaining structural strength, preventing the heat leakage issue present in conventional single-material designs

Inventive Principle:
Principle #40Composite materials

2Ease of manufacture

If the cover materials are joined at the outer surface in conventional designs, then the manufacturing process is simplified, but heat leakage increases due to direct contact with outside air

Engineering Contradiction:
Improvejoining processVSAvoidheat leakage
Core Design Contradiction:
Ease of manufactureVSLoss of energy

Solution Approach 1:

The patent relocates the cover material joining operation from the outer surface dimension to the inner dimension of the container. By joining covers internally, the design maintains manufacturing simplicity while adding the dimensional benefit of thermal isolation from the external environment, as the joined area no longer直接接触 outside air

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

3Quantity of substance

If conventional heat insulation methods are used, then the initial cost is reduced, but the duration of temperature maintenance is insufficient

Engineering Contradiction:
Improveinsulation materialVSAvoidtemperature maintenance duration
Core Design Contradiction:
Quantity of substanceVSDuration of action of stationary object

Solution Approach 1:

The patent utilizes phase transition materials (such as phase change materials that absorb or release heat during phase changes) within the insulation system. These materials undergo phase transitions at specific temperatures, actively regulating thermal energy storage and release, thereby extending the duration of temperature maintenance beyond what passive insulation materials alone can achieve

Inventive Principle:
Principle #36Phase transitions

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 prevents heat leakage, allowing the isothermal container to maintain stored items at a predetermined temperature for a longer duration by reducing heat transfer through the surface and enhancing insulation.

Implementation Method 1

a phase change material provided on a bottom portion and a wall portion of the box body and the box lid

Methodology Applied
Scientific EffectPhase change: Phase Change

Implementation Method 2

a heat insulating container having a bottom portion and a wall portion continuous with a peripheral edge of the bottom portion, the heat insulating container including a core material, an adsorbent, and two cover materials facing each other

Methodology Applied
Scientific EffectThermal insulation: Thermal Insulation

Data Source

PatentEP3984911B1Isothermal container
Publication Date: 2023.10.04 PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO LTD
  • EP3984911B1 patent drawingFigure 1
  • EP3984911B1 patent drawingFigure 2
  • EP3984911B1 patent drawingFigure 3

AI summary

Provided is an isothermal container capable of preventing heat leakage and maintaining a stored item at a predetermined temperature for a long time. An isothermal container includes: a vacuum heat insulating container 3; a vacuum heat insulating lid 4 configured to close the vacuum heat insulating container 3; a body protection case 32, and a lid outer protection case 42 and lid inner protection case 43 that cover the outside of the vacuum heat insulating container 3 and the outside of the vacuum heat insulating lid 4, respectively; a box body 51 housed inside the vacuum heat insulating container 3; a box lid 52 configured to close the box body 51; and a cold storage agent 57 provided on a bottom portion and a wall portion of the box body 51 and the box lid 52. An outer cover material 34 and an inner cover material 33 are joined together at faces facing the vacuum heat insulating lid 4 among faces constituting the wall portion of the vacuum heat insulating container 3. A joined part of the outer cover material 34 and the inner cover material 33 is located inside the body protection case 32 without being exposed to the outer surface of the body protection case 32.