Washing Liquid Preheating During Wetting to Shorten Wash Time
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional washing machines often result in a temperature gradient between laundry and washing liquid, leading to inadequate washing performance due to low average laundry temperature, especially with short washing times, and inefficient energy use, particularly when using cold water inlets.
Innovation Solution
Activating the heating device during the mains phase to heat the washing liquid to a lower temperature, allowing for efficient hot water control and reducing energy consumption by adjusting water inlet sources based on temperature limits, ensuring optimal heating and shorter wash times.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If heating is controlled predominantly continuously during the washing phase, then the target temperature is reached, but the total washing time increases
Solution Approach 1:
The heating device is activated during the mains phase before the washing phase begins, pre-heating the washing liquid to a first target temperature. This preliminary heating action reduces the heating time required during the subsequent washing phase, thereby decreasing the total washing time while still achieving the final target temperature.
2Use of energy by moving object
If the heating device is activated during the mains phase, then energy efficiency is improved, but the temperature control complexity increases
Solution Approach 1:
The heating process is segmented into two distinct phases: the mains phase where heating occurs to reach a first target temperature, and the washing phase where heating continues or adjusts to reach the final target temperature. This segmentation allows for optimized energy usage in each phase while maintaining manageable control complexity through clear phase-based control logic.
3Power
If hot water inlet is used during mains phase, then heating efficiency is improved, but energy consumption increases when cold water inlet is the only option
Solution Approach 1:
The system dynamically adapts its heating strategy based on water inlet availability. When only cold water inlet is available, the heating device operates at full power during the mains phase to efficiently heat the incoming cold water. When hot water inlet is available, the system can reduce heating power or utilize the pre-heated water, optimizing energy consumption based on the specific operating conditions.
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 method achieves improved washing performance and energy efficiency by maintaining a consistent target temperature, reducing wash time, and minimizing energy usage in both cold and hot water inlet scenarios, while ensuring effective bleach activation and uniform washing.
Implementation Method 1
a heating device included in the domestic appliance for heating the washing liquid is activated and the washing liquid is heated to a lower mains phase temperature
Implementation Method 2
a temperature sensor for detecting the temperature of the washing liquid
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a method in which a washing liquid in a suds container (3) is heated and a washing temperature of the washing liquid is set in order to wash laundry items (7) in a program-controlled domestic appliance (1) used for treating laundry items. In said method, laundry-specific and/or appliance-specific parameters, in particular the temperature of the washing liquid (6), are detected and the washing liquid is heated in dependence on the parameters in order to set a specific target temperature. The method is characterized in that, during a wetting phase (A2), in which washing liquid (6) is fed to the suds container (3) in order to wet the laundry items (7), a heating device (16) included in the domestic appliance is activated in order to heat the washing liquid (6), and the washing liquid (6) is heated by means of the heating device (16) to a wetting-phase temperature (Tn) that is lower than the target temperature (Tz) that is associated with a washing method selected by an operator. The method preferably also comprises a hot-water controller which causes the washing liquid to be heated to the target temperature during the wetting phase. The invention further relates to a corresponding domestic appliance.