Ultrasonic Laundry Humidity Detection Without Drum Rotation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing laundry treatment technologies face challenges in accurately and efficiently detecting laundry humidity and textile type without direct contact, often requiring drum rotation and suffering from 'blind thresholds' and limited sampling, which can lead to suboptimal treatment programs.

Innovation Solution

A laundry treatment apparatus equipped with an ultrasonic humidity detector unit that emits and receives ultrasonic waves, allowing for fast, contactless detection of laundry humidity and textile type, using frequency modulation and phase shift analysis to adapt treatment programs based on real-time moisture content and fabric composition.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conductivity-based humidity detection is used, then electrical contact with laundry is required, but this creates blind thresholds and limited sampling when laundry does not contact electrodes

Engineering Contradiction:
Improvehumidity detection accuracyVSAvoiddirect contact requirement
Core Design Contradiction:
Measurement precisionVSEase of operation

Solution Approach 1:

The patent replaces electrical contact-based conductivity measurement with ultrasonic wave-based measurement. The ultrasonic emitter and receiver detect humidity by measuring the speed of sound through the laundry, eliminating the need for electrical contacts with the laundry while providing continuous measurement capability.

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

2Measurement precision

If drum rotation is required for humidity detection, then sampling coverage is improved, but detection time increases and operational complexity rises

Engineering Contradiction:
Improvelaundry sampling coverageVSAvoiddetection time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent uses ultrasonic waves to detect humidity without requiring drum rotation. The ultrasonic emitter and receiver are positioned to measure the speed of sound through the laundry in the drum, providing rapid detection (within seconds) without mechanical movement or rotation of the drum.

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

3Measurement precision

If ultrasonic waves with frequency responsive to water are used, then humidity detection precision is improved, but device complexity increases

Engineering Contradiction:
Improvehumidity detection precisionVSAvoidfrequency selection requirements
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent utilizes the physical property that the speed of sound in water-saturated materials differs from dry materials. By measuring the speed of ultrasonic waves through the laundry and comparing it to reference values for different humidity levels, the system achieves precise humidity detection without complex frequency modulation or multiple transducers.

Inventive Principle:
Principle #35Parameter changes

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

Enables precise and efficient laundry treatment by providing accurate humidity and textile type detection, allowing for adaptive control of treatment processes, reducing energy consumption, and ensuring optimal drying conditions without the need for direct electrical contact or drum rotation.

Implementation Method 1

a laundry humidity detector unit having at least one emitting element which is adapted to emit ultrasonic waves and at least one receiving element which is adapted to receive ultrasonic waves

Methodology Applied
Scientific EffectUltrasonic wave transmission: Ultrasound

Implementation Method 2

at least one frequency or a frequency range that is responsive to water absorbed by laundry

Methodology Applied
Scientific EffectAcoustic absorption by water: Absorption (physical)

Data Source

PatentEP3175032B1Laundry treatment apparatus with humidity detector
Publication Date: 2018.09.12 ELECTROLUX APPLIANCES
  • EP3175032B1 patent drawingFigure 1
  • EP3175032B1 patent drawingFigure 2a~2b
  • EP3175032B1 patent drawingFigure 2c~5

AI summary

The invention relates to a laundry treatment apparatus (2) comprising: a housing, a drum (18a) rotatably arranged within the housing and adapted for receiving laundry, a laundry humidity detector unit (69) comprising at least one emitting element adapted to emit ultrasonic waves and at least one receiving element adapted to receive ultrasonic waves, a control unit (51) adapted to control operation of the treatment apparatus using at least one laundry treatment program, wherein the at least one emitting element is adapted to emit ultrasonic waves having at least one frequency or a frequency range that is responsive to water absorbed by laundry, and wherein the at least one emitting element is arranged in the housing to emit the ultrasonic waves towards the inner space of the drum (18a) and the at least one receiving element is arranged in the housing to receive ultrasonic waves from the inner space of the drum (18a).