Laundry treating apparatus having induction heater and control method thereof
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional laundry treating apparatuses without a circulating duct face challenges in accurately detecting dryness and determining the end of the drying process due to sensor malfunctions caused by detergents, washing-water, condensed water, or lint, and require multiple temperature sensors, making them complex to manufacture and operate.
Innovation Solution
A laundry treating apparatus using a single temperature sensor to detect dryness by measuring the temperature difference between the upper and lower sensors, which are strategically positioned to avoid contamination and overheating, allowing for accurate determination of drying completion based on natural convection and condensed water temperature changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a humidity sensor is used to detect dryness, then the drying end time can be determined, but the sensor becomes contaminated by detergent, washing-water or lint making it difficult to sense accurate humidity
Solution Approach 1:
The patent removes the humidity sensor from the contaminated environment inside the drum and extracts the measurement function to the condensing duct where air is sampled. The sensor is placed in a clean environment outside the drum, eliminating direct exposure to detergent, washing-water and lint while still enabling humidity detection through condensation analysis.
Solution Approach 2:
The patent introduces air as an intermediary medium to transfer humidity information from the drum interior to the sensor location. By sampling air through the condensing duct and analyzing its condensation properties, the system indirectly measures drum humidity without placing the sensor inside the contaminated environment.
2Measurement precision
If temperature sensors are installed near inlet and outlet of condensing duct to determine dryness, then drying end time can be detected, but three or more temperature sensors are required increasing manufacturing complexity
Solution Approach 1:
The patent makes the condensing duct serve multiple functions: it acts as both the condensation pathway for moisture removal and the measurement location for humidity detection. By placing the temperature sensor at the condensing duct inlet, the system uses the same structural component for both air flow control and environmental monitoring, eliminating the need for separate sensors in multiple locations.
Solution Approach 2:
The patent combines the humidity measurement function with the existing condensing duct structure. The temperature sensor is positioned at the duct inlet where air is already being directed for condensation, merging the measurement location with the functional air processing pathway and reducing the need for additional sensing components throughout the system.
3Productivity
If cooling water is supplied to condense moisture in humid air, then drying efficiency is improved, but condensed water and cooling water may contact temperature sensors causing temperature variations
Solution Approach 1:
The patent applies local quality by positioning the temperature sensor specifically at the condensing duct inlet where only ambient air is present, away from the condensation zone where cooling and condensed water are located. This localized placement ensures the sensor measures the temperature of the air entering the condensation process without being affected by the cooling water or condensed water in the duct.
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 effectively determines the drying end timing and load amount using a single sensor, reducing the risk of sensor malfunctions and simplifying the apparatus design, while ensuring accurate and efficient drying without direct contact with the drying target.
Implementation Method 1
an induction heater disposed on the tub and configured to heat an outer circumferential face of the drum contacting the heater
Implementation Method 2
a heater configured to heat the drum; the heater being an induction heater
Implementation Method 3
humid steam evaporated in heat exchange between the heated drum and the object is condensed into the condensed water inside the tub
Implementation Method 4
supplying cooling water to an inner circumferential face of the tub to condense moisture in humid air inside the tub
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Disclosed are a laundry treating apparatus, and more particularly, a laundry treating apparatus for heating a drum using an induction heater and a control method thereof. The object treating apparatus includes a tub (2); a drum (3) rotatably disposed within the tub (2) and for accommodating an object therein; an induction heater (8) disposed on the tub (2) and configured to heat an outer circumferential face of the drum (3) contacting the heater; a motor (6) to rotate the drum (3); and an upper temperature sensor (96) configured to detect a temperature around a space between the tub (2) and the drum (3), wherein the upper temperature sensor is disposed at an upper portion of the tub (2) and inside the tub (2); a lower temperature sensor (95) configured to detect a temperature around condensed water stored on a bottom of the tub (2), wherein the lower temperature sensor (95) is disposed at a lower portion of the tub (2) and inside the tub (2), wherein humid steam evaporated in heat exchange between the heated drum (3) and the object is condensed into the condensed water inside the tub (2) and the condensed water flows to the bottom of the tub (2); and a processor (9) configured to control a rotation of the drum (3) and an operation of the induction heater (8) to heat the drum (3) to heat and dry the object, wherein the processor (9) is further configured to determine an ending timing of the drying of the object based on a difference (delta T) between a temperature detected by the upper temperature sensor (96) and a temperature detected by the lower temperature sensor (95).