Heating device, cooking appliance with a heating unit, and method for making a heating element

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing cooking appliances face challenges in reliably and inexpensively manufacturing and installing heating elements that can efficiently radiate heat over a large area.

Innovation Solution

A cooking appliance featuring a flat heating element held by a holding device, where the heating element is designed as a grid or fabric with a large proportion of intermediate surfaces, allowing for effective heat radiation and uniform power density, and optionally includes a reflector for enhanced heat distribution and a central holder for stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If the heating element is fully supported by the holding device, then mechanical stability is improved, but heat radiation efficiency deteriorates due to reduced free surface area

Engineering Contradiction:
Improvemechanical stabilityVSAvoidheat radiation efficiency
Core Design Contradiction:
Stability of the object's compositionVSLoss of energy

Solution Approach 1:

The holding device is segmented into discrete holding points rather than continuous support, allowing the heating element to remain stable while maintaining large free surface area for heat radiation. The holding points are spaced to provide mechanical support without blocking heat radiation pathways.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The holding device provides localized support only at specific holding points along the outer edge or at discrete locations, rather than supporting the entire surface. This localized approach maintains mechanical stability at critical points while leaving the majority of the heating element surface free for efficient heat radiation.

Inventive Principle:
Principle #3Local quality

2Loss of energy

If the heating element uses a grid or fabric design with large intermediate surfaces, then heat radiation efficiency is improved, but manufacturing complexity increases

Engineering Contradiction:
Improveheat radiation efficiencyVSAvoidmanufacturing complexity
Core Design Contradiction:
Loss of energyVSEase of manufacture

Solution Approach 1:

The heating element is constructed as a flexible grid or fabric structure with thin heating conductor sections that can be easily formed and assembled. This flexible design allows for simple manufacturing processes while creating the desired grid pattern with large intermediate surfaces for efficient heat radiation.

Inventive Principle:
Principle #30Flexible shells and thin films

3Manufacturing precision

If the heating element is made with thin heating conductor sections, then heat distribution uniformity is improved, but mechanical strength deteriorates

Engineering Contradiction:
Improveheat distribution uniformityVSAvoidmechanical strength
Core Design Contradiction:
Manufacturing precisionVSStrength

Solution Approach 1:

The heating element combines thin heating conductor sections with supporting grid or fabric structure, creating a composite material system. The thin conductor sections ensure uniform heat distribution while the supporting grid structure provides the necessary mechanical strength and stability.

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

The solution enables reliable and cost-effective manufacturing of heating elements that efficiently radiate heat over a large area, ensuring uniform power distribution and preventing excessive sagging, while maintaining mechanical stability and ease of assembly.

Implementation Method 1

the heat output of the heating element can be radiated very well over a large area

Methodology Applied
Scientific EffectThermal radiation: Thermal Radiation

Implementation Method 2

reflect the heating energy radiated downwards upwards in the heating direction

Methodology Applied
Scientific EffectReflection: Reflection

Data Source

PatentEP3337291B1Heating device, cooking appliance with a heating unit, and method for making a heating element
Publication Date: 2020.09.09 E G O ELEKTRO GERAETEBAU GMBH
  • EP3337291B1 patent drawingFigure 1~2
  • EP3337291B1 patent drawingFigure 3
  • EP3337291B1 patent drawingFigure 4

AI summary

A heating device has a flat heating element and a holding device for the heating element, the heating element being held on the holding device along an outer edge and running freely within the holding device with at least 70% of its area. The heating element has a fabric that at least partially has heating conductor material. Thus, warp threads can advantageously consist of electrically conductive heating conductor material, and weft threads can consist of carbon fibers or ceramic fibers. The heating element may be centrally supported or provided with structuring across its surface to stabilize it, e.g. corrugated.