Cooking Appliance Analog Switch Multiplexing Temperature Sensors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Induction heating cooking appliances face challenges in achieving uniform temperature distribution due to non-uniform magnetic field distribution, leading to inaccurate temperature measurement and increased costs when using multiple temperature sensors with limited A/D ports.
Innovation Solution
A cooking appliance with multiple temperature sensors and an analog switch that allows for temperature prediction using a processor-controlled temperature prediction function, enabling independent sensing of multiple temperature areas over a wide range using only one A/D port, and alternating sensing values from different sensors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If multiple temperature sensors are provided to sense temperatures of various areas, then temperature measurement accuracy is improved, but manufacturing cost increases
Solution Approach 1:
The patent merges multiple temperature sensor signals into a single A/D port by using an analog switch to multiplex the signals. This allows multiple sensors to be connected without requiring multiple A/D ports, thereby maintaining temperature measurement accuracy across various areas while avoiding the need for additional expensive components and reducing manufacturing cost.
Solution Approach 2:
The single A/D port is made universal by using the analog switch to sequentially connect it to multiple temperature sensors. This allows one A/D port to serve multiple sensing functions, eliminating the need for dedicated A/D ports for each sensor and reducing overall system cost while maintaining the capability to measure temperatures at multiple locations.
2Ease of manufacture
If an analog switch is used to acquire sensing values of multiple temperature sensors using one A/D port, then manufacturing cost is reduced, but measurement accuracy deteriorates due to non-linear characteristics of temperature sensor resistance
Solution Approach 1:
The patent applies parameter changes by using different prediction functions based on temperature ranges. The processor selects appropriate prediction functions that account for the non-linear resistance characteristics of temperature sensors at different temperature levels. This compensation method corrects the measurement errors introduced by the analog switch and non-linear sensor characteristics, thereby maintaining high measurement accuracy while using cost-effective components.
Solution Approach 2:
The system uses feedback through prediction functions that are determined based on previously predicted temperatures. This feedback mechanism allows the system to continuously adjust and compensate for non-linear characteristics, ensuring accurate temperature measurements even when using an analog switch to multiplex sensor signals from multiple sensors with non-linear resistance properties.
3Adaptability or versatility
If multiple A/D ports are provided to acquire sensing values from multiple temperature sensors, then temperature sensing capability is improved, but device complexity increases
Solution Approach 1:
The patent merges multiple A/D port functions into a single A/D port by implementing an analog switch multiplexer. This consolidation maintains the versatility of sensing temperatures at multiple locations while significantly reducing device complexity by eliminating the need for multiple A/D ports and their associated circuitry, thereby simplifying the overall system architecture.
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 solution minimizes manufacturing costs, allows for accurate temperature measurement across various areas, and extends the range of temperature sensing without limiting the number of sensors, improving the accuracy and efficiency of temperature prediction.
Implementation Method 1
the induction heating method generates an eddy current in the object to be heated consisting of a metal component using a magnetic field generated around the coil to heat the object to be heated itself
Implementation Method 2
the induction heating method generates an eddy current in the object to be heated consisting of a metal component using a magnetic field generated around the coil to heat the object to be heated itself
Implementation Method 3
due to non-linear characteristics of a resistance value of the temperature sensor
Data Source
AI summary
A cooking appliance can include a first temperature sensor; a second temperature sensor; an analog switch configured to select one of a sensing value of the first temperature sensor and a sensing value of the second temperature sensor as a selected sensing value; and a processor configured to receive the selected sensing value from the analog switch, and apply the selected sensing value to at least one temperature prediction function and generate a predicted temperature based on an output of the at least one temperature prediction function. Also, the cooking appliance can include an upper plate configured to support an object to be heated, and a working coil configured to generate magnetic fields for heating the object.