Steam Outlet Sensing for Automatic Cooking Phase Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing cooking appliances lack effective automatic control mechanisms to prevent overcooking and drying out of food, as they rely on temperature sensors alone, which do not account for the thermal mass and geometry of the food being cooked.

Innovation Solution

The method utilizes the signal from a steam outlet sensor to control the cooking process by measuring the energy supplied during the warm-up phase until steam emerges, allowing for adjustments in heating power and target cooking chamber temperature to prevent surface overcooking, and uses the time until steam emerges to determine subsequent cooking phases, thereby improving control over the cooking process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If temperature sensor alone is used to control cooking, then device complexity is reduced, but manufacturing precision of cooking process deteriorates

Engineering Contradiction:
Improvecontrol mechanismVSAvoidcooking process control
Core Design Contradiction:
Device complexityVSManufacturing precision

Solution Approach 1:

The patent implements feedback control by using a steam outlet sensor to detect when steam escapes from the food, which triggers automatic adjustment of heating power and cooking chamber temperature. This closed-loop feedback system continuously monitors the cooking state and adjusts parameters in real-time, enabling precise control without requiring complex manual intervention or multiple sensors.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The cooking system performs self-adjustment based on the steam detection signal. When the sensor detects steam escape, the controller automatically reduces heating power and adjusts temperature parameters without external intervention. This self-service mechanism simplifies the control structure while maintaining high cooking precision by leveraging the natural physical indicator (steam escape) of the cooking process.

Inventive Principle:
Principle #25Self-service

2Productivity

If heating power is maintained high during warm-up phase, then productivity is improved, but object-affected harmful factors increase

Engineering Contradiction:
Improvecooking speedVSAvoidsurface overcooking and drying out
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent applies dynamic control by continuously adjusting heating power based on the detected cooking stage. During the warm-up phase, high heating power is applied to accelerate cooking, but when the steam outlet sensor detects steam escape, the system dynamically reduces heating power to prevent surface overcooking. This dynamic adjustment optimizes both cooking speed and food quality throughout the process.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system performs preliminary high-power heating during the warm-up phase to quickly bring the food to the cooking temperature, then switches to lower power once steam escape is detected. This preliminary action approach allows the system to maximize cooking speed initially, then transition to quality-preserving mode, effectively separating the high-speed heating phase from the quality-control phase.

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 enables precise control of cooking phases, preventing overcooking and drying out by adjusting heating power and temperature based on the thermal mass and geometry of the food, ensuring optimal cooking conditions.

Implementation Method 1

The steam outlet sensor comprises an opening in the cooking chamber and a temperature sensor arranged outside of the opening. If steam escapes from the food to be cooked, hot gas escapes through the opening, which can be measured by the temperature sensor.

Methodology Applied
Scientific EffectTemperature sensing: Thermocouple

Implementation Method 2

a conventional resistive heater with top heat and bottom heat for heating the gases in the cooking chamber

Methodology Applied
Scientific EffectHeating: Heating

Implementation Method 3

The device also has a steam generator for producing steam and for introducing the steam into the cooking chamber

Methodology Applied
Scientific EffectEvaporation: Evaporation

Data Source

PatentEP2189084B1Refining preparation with vapour escape detection
Publication Date: 2011.08.24 V-ZUG AG
  • EP2189084B1 patent drawingFigure 1~2D
  • EP2189084B1 patent drawingFigure 3A~3D

AI summary

The method involves heating a food to be cooked at a certain temperature during a heating phase, where the heating temperature is more than 90 degree centigrade. A parameter is measured during the heating phase, where the parameter depends on the energy supplied to a cooking chamber (1) up to a steam outlet. An independent claim is included for a cooking appliance.