Steam Escape Detection for Automatic Cooking Power Control
Find Innovative SolutionsGenerate 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 that cannot distinguish between steam from the food and steam from the generator, leading to inefficient heating management.
Innovation Solution
The method utilizes a steam outlet sensor to detect the point of steam emergence from food, allowing for precise control of heating power and temperature adjustments, distinguishing between steam from the food and the generator, and using the time until steam emergence to determine subsequent cooking phases, enabling autonomous control of the cooking process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a temperature sensor is used to detect steam escape, then steam detection is possible, but the sensor cannot distinguish between steam from food and steam from the generator
Solution Approach 1:
The detection process is segmented into two distinct phases: a steam generation phase where the steam generator operates and steam escape is suppressed, and a detection phase where the steam generator is turned off and steam escape from food is detected. This temporal segmentation allows the temperature sensor to distinguish between steam from the generator and steam from the food.
Solution Approach 2:
The steam generator is operated in advance during a warm-up phase to generate steam and heat the cooking chamber, and this action is deliberately suppressed during the detection phase. By performing the steam generation action beforehand and then stopping it, the system creates a clear distinction between generator steam and food steam.
2Productivity
If heating power is maintained high to cook food efficiently, then cooking speed is improved, but the food surface overheats and dries out
Solution Approach 1:
The heating process uses periodic action by alternating between high-power heating phases and lower-power detection phases. During the detection phase when steam escape is detected, the heating power is reduced or switched off temporarily, allowing the food surface to cool slightly and prevent overheating, while still maintaining overall cooking progress.
Solution Approach 2:
The system uses feedback from the temperature sensor detecting steam escape to automatically adjust the heating power. When steam escape is detected, the controller reduces heating power; when steam escape stops, heating power can be increased again. This closed-loop feedback ensures the food surface temperature is controlled to prevent drying while maintaining cooking efficiency.
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 prevents overcooking and drying by adjusting heating power and temperature based on steam emergence, ensuring optimal cooking conditions and improving the automatic control of the cooking process, allowing for precise temperature and time management of various food types.
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.
Implementation Method 2
The device also has a steam generator 4, as described in EP 1 166 694, for example.
Data Source
Figure 1~2
Figure 3
AI summary
The method for preparing cooked food in a cooking appliance is such that in the event of detection of steam emission from the food the heating power and/or a nominal cooking chamber temperature, according to which the heating power is regulated, is reduced, and/or the time duration (t1) from the beginning of the heating up phase of the cooked food to steam emission is measured and depending upon this time duration a time duration (t2, t3), or a starting time point, of at least one subsequent preparation phase is established. An independent claim is included for a cooking appliance with a control unit for automatic implementation of the method.