Clothes Dryer Infrared Load Temperature Control for Even Drying
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Clothes dryers often misjudge the temperature of laundry due to discrepancies between the drum temperature and load temperature, leading to inefficient drying and potential drum rotation issues, which existing moisture sensors cannot accurately detect due to interference and environmental factors.
Innovation Solution
Incorporating an infrared temperature sensor to take multiple readings over time, determining temperature variations to assess load characteristics and control the dryer's operation, ensuring accurate temperature monitoring and efficient drying cycles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If drum temperature or exhaust air temperature is used to determine load temperature, then temperature measurement is simple, but the temperature reading is inaccurate because drum temperature differs from load temperature
Solution Approach 1:
The patent replaces contact-based temperature sensing (thermocouples, RTDs) with non-contact infrared temperature sensing. The infrared sensor measures the thermal radiation emitted by the laundry load directly, eliminating the need for physical contact and avoiding the temperature discrepancy between drum and load. This optical measurement approach provides accurate load temperature without the complexity of multiple contact sensors or temperature conversion algorithms.
2Measurement precision
If moisture strips are used to detect moisture content, then moisture detection is implemented, but the readings are inaccurate due to electronic interference and environmental conditions
Solution Approach 1:
The patent replaces electrical conductivity-based moisture detection (moisture strips) with optical/infrared temperature-based moisture detection. By measuring the temperature of the laundry load and analyzing temperature variations over time, the system infers moisture content without using electrical sensors that are susceptible to interference. This eliminates the harmful effects of electronic interference, steam, and chemistry dispensing on the detection system.
3Reliability
If no drum rotation detection is implemented, then device complexity is low, but the dryer cannot detect drum failures and continues heating causing uneven drying
Solution Approach 1:
The patent implements feedback-based drum rotation detection by continuously monitoring temperature readings from the infrared sensor. When the drum rotates, the temperature readings show characteristic variations as different portions of the laundry are exposed to the sensor. If the drum fails to rotate, the temperature readings remain static or show abnormal patterns. The controller analyzes these temperature variations to detect drum rotation status and can alert the user or adjust operation accordingly, providing reliable failure detection without complex mechanical sensors.
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 method allows for precise control of dryer operations based on load temperature, ensuring even drying and preventing drum rotation failures by accurately determining when to start or end cycles, thus improving drying performance and preventing overheating or underheating.
Implementation Method 1
an infrared temperature sensor directed toward the treating chamber
Data Source
AI summary
A method for controlling a clothes dryer based on a characteristic of the load determined by temperatures provided by an infrared sensor.