Steam Generator Heater Control for Laundry Machine Overheating

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing laundry machines with steam generators are prone to overheating and fire due to malfunctioning water level detection, leading to increased power consumption and maintenance issues, as well as inaccurate operation time limits.

Innovation Solution

Implementing a controller that sets and updates an operation limit time for the heater based on factors like applied voltage, water quantity, temperature variation rate, and water pressure, ensuring the heater is turned off before overheating occurs, and using a water quantity detecting unit to prevent incorrect water level detection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Duration of action of stationary object

If the heater operates continuously to generate steam, then steam supply is maintained, but overheating and fire hazards occur due to malfunctioning water level detection

Engineering Contradiction:
Improveheater operation durationVSAvoidoverheating and fire hazard
Core Design Contradiction:
Duration of action of stationary objectVSObject-affected harmful factors

Solution Approach 1:

The controller sets an operation limit time for the heater in advance based on detected water quantity. This preliminary time limit prevents the heater from operating beyond a safe duration, thereby preventing overheating and fire hazards before they can occur.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system continuously monitors water quantity using a water quantity detecting unit and adjusts the heater's operation limit time accordingly. This feedback mechanism ensures the heater operates only within safe parameters based on actual water availability, preventing overheating conditions.

Inventive Principle:
Principle #23Feedback

2Productivity

If the operation limit time is set too long, then steam generation is sufficient, but power consumption increases and maintenance needs increase

Engineering Contradiction:
Improvesteam generation efficiencyVSAvoidpower consumption
Core Design Contradiction:
ProductivityVSUse of energy by moving object

Solution Approach 1:

The operation limit time is not fixed but dynamically adjusted based on detected water quantity. The controller calculates an appropriate operation limit time that matches the actual water available, optimizing steam generation efficiency while preventing excessive power consumption and maintenance needs.

Inventive Principle:
Principle #15Dynamics

3Ease of operation

If water level detection is used to control heater operation, then operation control is simplified, but inaccurate detection leads to incorrect operation time limits

Engineering Contradiction:
Improveheater control simplicityVSAvoidwater level detection accuracy
Core Design Contradiction:
Ease of operationVSMeasurement precision

Solution Approach 1:

The patent replaces mechanical water level detection with a water quantity detecting unit that measures actual water quantity. This substitution provides more accurate measurement data for the controller to set appropriate operation limit times, eliminating the inaccuracies of traditional water level detection while maintaining simple automated control.

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

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

Prevents overheating and fires, reduces power consumption, enhances reliability by accurately controlling the heater's operation time, and minimizes maintenance needs by preventing steam generator malfunctions.

Implementation Method 1

a heater (55) for heating the water stored in the steam generator (50)

Methodology Applied
Scientific EffectJoule heating: Joule Heating

Implementation Method 2

a water quantity detecting unit detecting a water quantity within the steam generator (50)

Methodology Applied
Scientific EffectPressure measurement:

Implementation Method 3

a temperature sensor (57) for measuring a temperature within the steam generator (50)

Methodology Applied
Scientific EffectTemperature measurement:

Implementation Method 4

The steam generator (50) generates steam by heating the water stored therein

Methodology Applied
Scientific EffectEvaporation: Evaporation

Data Source

PatentEP1873297B1Laundry machine and method of controlling steam generator thereof
Publication Date: 2015.01.07 LG ELECTRONICS INC
  • EP1873297B1 patent drawingFigure 1
  • EP1873297B1 patent drawingFigure 2~3
  • EP1873297B1 patent drawingFigure 4

AI summary

A laundry machine and controlling method thereof are disclosed, by which malfunctions of a steam generator and laundry machine and fire due to the overheating of a heater can be prevented. The present invention includes a steam generator having a heater and a controller turning of the heater if an operation time of the heater exceeds a operation limit time set in the course of driving the heater.