Dishwasher Zeolite Drying Sensor Layout for Precise Drying Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing dishwasher drying control systems rely on expensive temperature sensors placed near the sorption column due to high temperatures, making them costly and complex, and lack precise control due to time-based drying methods that don't account for varying loads.
Innovation Solution
A temperature sensor is positioned upstream of the drying device and downstream of the washing compartment to detect significant temperature changes in the air circuit, allowing for the use of simpler, cost-effective components like NTC resistors, which can also monitor fan and heater functionality for error detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If temperature sensors are placed near the sorption column to detect high temperatures for drying control, then drying control precision is improved, but manufacturing cost increases due to expensive high-temperature sensor requirements
Solution Approach 1:
The patent introduces ambient air as an intermediary medium to transfer temperature information from the high-temperature zone near the sorption column to a low-temperature measurement zone. The temperature sensor measures the temperature of ambient air that has been heated by proximity to the sorption column, indirectly detecting the drying process state without requiring the sensor to withstand extreme temperatures directly.
Solution Approach 2:
The patent creates a temperature copy or proxy measurement by measuring ambient air temperature near the sorption column rather than directly measuring the sorption column temperature. This temperature copy correlates with the actual drying process temperature but allows use of inexpensive standard sensors instead of expensive high-temperature sensors.
2Measurement precision
If temperature-based drying control is implemented, then drying control precision is improved compared to time control, but device complexity increases due to additional temperature sensing and control systems
Solution Approach 1:
The patent leverages the existing ambient air in the dishwasher as a self-service temperature indicator. The ambient air naturally circulates and reflects the thermal state of the drying process without requiring complex temperature probe installations or additional thermal coupling mechanisms. The control system simply monitors this naturally occurring temperature signal.
Solution Approach 2:
The patent changes the measurement parameter from direct sorption column temperature to ambient air temperature. This parameter change simplifies the measurement system while maintaining correlation with the drying process, as ambient air temperature responds to the thermal field generated by the sorption column during operation.
3Ease of manufacture
If standard low-cost temperature sensors are used upstream of the sorption column, then manufacturing cost is reduced, but temperature detection capability for high-precision drying control is worsened
Solution Approach 1:
The patent implements a feedback mechanism where the ambient air temperature measured by the inexpensive sensor is continuously monitored and used to control the drying process. The control system adjusts drying parameters based on the ambient air temperature readings, creating a closed-loop feedback system that compensates for the lower measurement precision of standard 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 setup reduces manufacturing costs and provides more precise drying control by using standard components, enabling detection of temperature changes for both drying control and fault identification, offering customizable drying results and reduced maintenance costs.
Implementation Method 1
temperature sensor which is arranged upstream of the drying device and downstream of the washing container in the direction of flow of air circulating in the air circuit
Implementation Method 2
a reversibly dehydratable drying agent as the water-absorbing material. They adopt a characteristic of zeolite, which gives off heat when it absorbs water as a result of the absorption reaction
Implementation Method 3
The more water the zeolite absorbs, the higher its temperature rises
Data Source
Figure 1~2
Figure 3
AI summary
The invention relates to a dishwashing machine having a washing compartment (1) and a drying unit (7) which comprises an absorption column (19) with a drying agent (21) which can be reversibly dehydrated, and having an air circulation loop through the washing compartment (1) and the drying unit (7). The invention is characterized by a temperature sensor (15, 17) which is arranged in front of the drying unit (7) and to the rear of the washing compartment (1) with respect to the direction of the flow of air circulating in the air circulation loop.