Method for controlling a cooking process in a cooking device and cooking device

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing cooking technologies face challenges in reliably achieving a desired degree of browning for products like rolls, especially with variations in cooking chamber temperature and mixed loads, as they fail to accurately control the cooking process based on surface temperature and humidity.

Innovation Solution

The method divides the cooking process into two sections: heating the product to the boiling point of water and maintaining a surface temperature above it, using a browning counter that estimates energy input and applies the Arrhenius law to predict browning, with sensors and a database to adjust parameters for optimal browning.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the cooking process is controlled based on cooking chamber temperature and total heat input, then the overall cooking progress can be monitored, but the surface browning cannot be reliably predicted or controlled

Engineering Contradiction:
Improvebrowning prediction accuracyVSAvoidcontrol system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The invention changes the control parameter from bulk cooking chamber temperature to surface temperature of the product. By focusing measurements on the product surface temperature and applying the Arrhenius law to model browning kinetics, the system achieves reliable browning prediction without requiring complex multi-sensor arrays or advanced algorithms. This parameter change directly addresses the contradiction by improving measurement precision for browning while keeping the control system relatively simple.

Inventive Principle:
Principle #35Parameter changes

2Stability of the object's composition

If the cooking chamber temperature is adjusted to accommodate mixed loads, then cooking uniformity across different products can be improved, but the surface browning of individual products becomes unpredictable

Engineering Contradiction:
Improvecooking consistencyVSAvoidbrowning control accuracy
Core Design Contradiction:
Stability of the object's compositionVSMeasurement precision

Solution Approach 1:

The invention implements feedback control by continuously monitoring the product surface temperature and comparing it against the Arrhenius model predictions. The system calculates a browning counter value based on the integrated effect of temperature and time, and uses this feedback to adjust cooking parameters. This allows the system to maintain cooking consistency for mixed loads while still achieving reliable browning control for individual products through continuous adaptation.

Inventive Principle:
Principle #23Feedback

3Manufacturing precision

If extensive test series are conducted to determine process parameter adjustments for all product-process-appliance combinations, then cooking parameter optimization can be achieved, but the time and resource requirements become prohibitively large

Engineering Contradiction:
Improvecooking parameter optimizationVSAvoidtesting time
Core Design Contradiction:
Manufacturing precisionVSLoss of time

Solution Approach 1:

The invention enables the cooking system to self-adjust by using the Arrhenius law model that automatically calculates optimal cooking parameters based on real-time surface temperature measurements. Instead of requiring pre-determined parameters from extensive testing for each product combination, the system serves itself by continuously modeling the browning process and adapting parameters on-the-fly. This eliminates the need for exhaustive test series while maintaining cooking parameter optimization.

Inventive Principle:
Principle #25Self-service

4Adaptability or versatility

If the door remains open for a short time during loading, then temperature drop is minimized, but the load cannot be changed; if the door remains open longer to change load, then loading flexibility is improved, but temperature stability deteriorates and browning becomes unreliable

Engineering Contradiction:
Improveload change flexibilityVSAvoidcooking chamber temperature stability
Core Design Contradiction:
Adaptability or versatilityVSTemperature

Solution Approach 1:

The invention applies preliminary action by pre-calculating the expected temperature drop based on door opening duration and loading conditions using the Arrhenius model. Before the actual cooking process begins, the system determines the initial browning counter value and adjusts subsequent cooking parameters to compensate for anticipated temperature variations. This allows flexible load changes with extended door opening while maintaining reliable browning control through proactive parameter adjustment.

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

This approach allows for precise estimation and control of browning, ensuring consistent results by accounting for surface temperature and energy input, even with varying cooking conditions, and allows for self-learning adjustments based on user feedback and sensor data.

Implementation Method 1

a heating element (18), with which a cooking chamber atmosphere can be heated

Methodology Applied
Scientific EffectHeating: Heating

Implementation Method 2

the specific heat input into the product to be cooked is determined as the key parameter

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 3

a fan wheel (20), with which the cooking chamber atmosphere can be circulated

Methodology Applied
Scientific EffectConvection: Convection

Implementation Method 4

Prior art already considers using weight sensors, optical image recognition, etc., to detect the load in the cooking chamber

Methodology Applied
Scientific EffectWeight measurement:

Implementation Method 5

information about the load inside the cooking chamber can be obtained by analyzing, for example, the temperature of the cooking chamber atmosphere

Methodology Applied
Scientific EffectThermal radiation: Thermal Radiation

Implementation Method 6

using a browning counter that estimates energy input and applies the Arrhenius law to predict browning

Methodology Applied
Scientific EffectArrhenius law:

Implementation Method 7

the evaporation of water in a near-surface layer, which necessitates a specific amount of energy per unit area

Methodology Applied
Scientific EffectEvaporation: Evaporation

Data Source

PatentEP3118524B1Method for controlling a cooking process in a cooking device and cooking device
Publication Date: 2022.03.09 RATIONAL AG
  • EP3118524B1 patent drawingFigure 1
  • EP3118524B1 patent drawingFigure 2
  • EP3118524B1 patent drawing

AI summary

The invention relates to a method for controlling a cooking process in a cooking appliance (10), in which a specific browning heat input into the product to be cooked begins at a point in time when the surface of a product to be cooked exceeds a temperature in the order of magnitude of the boiling temperature of water Product summed up to a current browning value and the cooking process is ended when a predetermined browning value is reached. The invention also relates to a cooking appliance (10) with a cooking chamber (12), a heating device (18) and a controller (22), the controller (22) containing a browning counter (37) which a specific browning heat input to a browning value can add up, wherein the controller (22) can control the cooking process depending on the browning value.