Dishwasher Sorption Drying Control for Overheating Prevention

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Household dishwashers with sorption drying systems face challenges in maintaining functional reliability due to vulnerabilities in their electrical components' operation, particularly during sorption and desorption processes, which can be affected by mains voltage and frequency deviations, leading to potential overheating and material damage.

Innovation Solution

The implementation of an additional control unit specifically for the sorption drying device, which monitors and controls the heating and fan units, ensuring safe operation within permissible ranges by switching them off in case of critical parameter deviations or communication errors, thereby preventing overheating and ensuring thermal safety.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the heating device is operated at high temperatures for desorption, then the sorption material can be regenerated effectively, but the risk of overheating and material damage increases

Engineering Contradiction:
Improvefunctional reliability of sorption drying deviceVSAvoidoverheating and material damage
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The additional control unit is activated before the heating device operates to pre-establish safety monitoring and control mechanisms. This preliminary setup ensures that safety parameters are defined and monitoring is in place before the high-temperature desorption process begins, preventing overheating before it can occur.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The additional control unit continuously monitors the operation of the heating device and sorption material temperature during the desorption process. This feedback mechanism allows real-time detection of temperature deviations and automatic adjustment or shutdown to prevent overheating and material damage while maintaining effective regeneration.

Inventive Principle:
Principle #23Feedback

2Reliability

If an additional control unit is added to monitor electrical components, then the functional reliability is improved, but the device complexity increases

Engineering Contradiction:
Improvefunctional reliability of sorption drying deviceVSAvoidcontrol system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The control system is segmented into two independent units: the main control device for overall dishwasher operation and the additional control unit specifically for the sorption drying device. This segmentation allows the additional control unit to focus solely on monitoring heating and fan units, simplifying its design while improving overall reliability through specialized monitoring.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The additional control unit acts as an intermediary between the main control device and the electrical components of the sorption drying device. It receives commands from the main control device and directly controls the heating device and fan unit, providing a dedicated monitoring layer that improves reliability without requiring the main control device to handle all monitoring functions.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Productivity

If the sorption material is heated to high temperatures for desorption, then the water can be removed effectively, but the reversibly dehydratable properties may be compromised

Engineering Contradiction:
Improvedesorption efficiencyVSAvoidreversibly dehydratable properties of sorption material
Core Design Contradiction:
ProductivityVSStability of the object's composition

Solution Approach 1:

The heating process is made dynamic through continuous monitoring and adjustment by the additional control unit. The heating device operates at variable temperatures rather than fixed high temperatures, adjusting in real-time based on feedback from temperature sensors and moisture content monitoring. This dynamic control maintains desorption efficiency while preventing temperatures that would damage the sorption material's reversible properties.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The desorption process uses controlled parameter changes, particularly temperature and time, to optimize water removal while preserving material properties. The additional control unit monitors and adjusts these parameters dynamically, ensuring that the heating remains effective for desorption but does not exceed thresholds that would permanently damage the sorption material's reversibly dehydratable characteristics.

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

This solution enhances the functional reliability of the sorption drying device by preventing overheating and material damage, ensuring the sorption material is heated gently and maintaining its reversibly dehydratable properties over the dishwasher's service life, while also protecting against electrical fluctuations.

Implementation Method 1

this is heated to such high temperatures with the aid of at least one heating device that the water stored in the sorption material can escape as hot water vapor

Methodology Applied
Scientific EffectEvaporation: Evaporation

Implementation Method 2

their reversibly dehydratable sorption drying material is deprived of moisture from the air that is passed through due to condensation

Methodology Applied
Scientific EffectCondensation: Condensation

Data Source

PatentEP2599426B1Domestic dishwasher with a sorption drying device and associated method
Publication Date: 2015.03.04 BSH HAUSGERATE GMBH
  • EP2599426B1 patent drawingFigure 1
  • EP2599426B1 patent drawingFigure 2
  • EP2599426B1 patent drawingFigure 3~4

AI summary

In a household dishwasher (GS), at least one additional control unit (ZE) is provided to control at least one electrical component (HZ1) of its sorption drying device (STE) in addition to the main control device (HE), which controls the sorption drying device (STE), in particular its heating device (HZ1) and/or fan unit (LT), switches off when a critical parameter, in particular mains voltage deviation (ΔU) and/or mains frequency deviation (Δf) of the electrical energy supply network (EN), with which the main control device (HE) and/or the additional control unit (ZE) in Active connection is exceeded in the respective sorption and / or desorption process.