Laundry Dryer Water-Level Detection for Reliable Filter Cleaning

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional laundry treating apparatuses fail to adequately clean filters and heat exchangers due to reliance on condensate water generation during drying, lacking a mechanism to determine the required cleaning water level and supplementing water when insufficient condensate is collected.

Innovation Solution

A method for controlling the laundry treating apparatus that includes sensing the water level in a collector, guiding user intervention or automatic water supply when the level is insufficient, and ensuring cleaning operations are performed even when condensate water is below the required amount, with optional detergent mixing and notification features.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If cleaning is performed using only condensate water generated during drying, then the system structure remains simple, but the filter or heat exchanger is not sufficiently cleaned when condensate water amount is small

Engineering Contradiction:
Improvecleaning effectivenessVSAvoidwater supply control system
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The system performs preliminary detection of condensate water amount before cleaning operation, and preliminarily determines whether water supplementation is needed. This allows the system to prepare adequate cleaning water in advance, ensuring reliable cleaning effectiveness without requiring complex real-time control during the cleaning process itself.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system incorporates feedback mechanisms by detecting the actual amount of condensate water generated during drying and using this information to determine whether additional water supplementation is required. This feedback loop ensures that cleaning operations always have sufficient water regardless of varying drying conditions.

Inventive Principle:
Principle #23Feedback

2Reliability

If the system automatically supplements water when condensate water is insufficient, then cleaning reliability is improved, but the control system complexity increases

Engineering Contradiction:
Improvecleaning water availabilityVSAvoidwater level detection and control system
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The system performs self-service by automatically detecting water level conditions and supplementing water without requiring external intervention. The control system monitors condensate water accumulation and autonomously determines when and how much additional water to supply, ensuring cleaning water availability while minimizing operational complexity through automated decision-making.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The system replaces complex mechanical water supply mechanisms with electronic sensing and control. By using water level detectors and electronic control units to manage water supplementation, the system achieves reliable cleaning water availability with simpler, more controllable electronic systems rather than complex mechanical arrangements.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Quantity of substance

If water is supplemented from a water supply source when condensate water level is low, then sufficient cleaning water is ensured, but the water management system becomes more complex

Engineering Contradiction:
Improvecleaning water amountVSAvoidwater collector and supply system
Core Design Contradiction:
Quantity of substanceVSDevice complexity

Solution Approach 1:

The water collector and supply system serves multiple functions: it collects condensate water during drying, stores it for later use, detects water level conditions, and supplements water when needed. By making the water management system multi-functional, the patent ensures sufficient cleaning water availability without requiring entirely separate systems for each function, thereby limiting complexity increase.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The system merges the condensate collection function with the cleaning water supply function into a single integrated water management system. The water collector serves both as a condensate storage device and as a cleaning water reservoir, with integrated level detection and supplementation capabilities. This merging ensures adequate cleaning water quantity while reducing the number of separate components needed.

Inventive Principle:
Principle #5Merging (Combining)

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

Ensures thorough cleaning of filters and heat exchangers by ensuring adequate water supply for cleaning, preventing incomplete cleaning due to low condensate levels, and providing user guidance or automatic intervention for effective maintenance.

Implementation Method 1

a water collector water-level sensor configured to detect a water-level inside the water collector... a floater ascending or descending along a height direction of the water collector according to a water-level inside the water collector; a permanent magnet fixed to the floater; and a magnetic force sensor disposed in the cabinet for transmitting a magnitude of a magnetic force exerted from the permanent magnet to the controller

Methodology Applied
Scientific EffectMagnetic force interaction: Magnetism

Implementation Method 2

a pump configured to move the water from the water collector to the water discharger

Methodology Applied
Scientific EffectMechanical force: Mechanical Force

Implementation Method 3

a first heat exchanger that cools air introduced into the duct from the drum to remove moisture included in the air

Methodology Applied
Scientific EffectCondensation: Condensation

Implementation Method 4

a second heat exchanger that heats air that has passed through the first heat exchanger

Methodology Applied
Scientific EffectThermal energy transfer: Heating

Data Source

PatentEP4041945B1Method for controlling a laundry treating apparatus
Publication Date: 2026.03.11 LG ELECTRONICS INC
  • EP4041945B1 patent drawingFigure 1
  • EP4041945B1 patent drawingFigure 2
  • EP4041945B1 patent drawingFigure 3

AI summary

Disclosed is a laundry treating apparatus including: a water discharger supply pipe for supplying water stored in a water collector to a water discharger; a water supply pipe constructed to connect the water discharger and the water collector to each other; and a water collector water-level sensor for measuring a water-level inside the water collector, and a controller configured to control the laundry treating apparatus comprising: a water-level sensing operation in which the water collector water-level sensor measures the water-level of the water collector during a drying operation; and a cleaning water supply operation in which when the water-level of the water collector is lower than a predefined cleaning-related reference water-level, a water supply valve is controlled to supply water stored in the water discharger to the water collector.