Laundry treatment apparatus with pumping device and method for operating the laundry treatment apparatus
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional laundry care appliances face challenges in ensuring complete dissolution of laundry care substances, leading to potential damage and discoloration of laundry due to undissolved residues, especially when overdosed, and existing methods fail to reliably prevent uncontrolled backflow of washing liquid with undissolved detergent.
Innovation Solution
A laundry care appliance with a dual-pump system that alternates between pumping washing liquid into and out of the tub through different lines, using reduced pump capacity to create convection and prevent backflow, ensuring complete dissolution of laundry care substances by alternating between pump-out and pump-around lines.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If a recirculation pump is used to pump washing liquid back into the tub, then dissolution of laundry care substance is enhanced through convection, but uncontrolled backflow of washing liquid with undissolved detergent may occur
Solution Approach 1:
The system dynamically switches between two pump modes: recirculation mode for enhanced dissolution and drain mode for controlled removal. The control unit monitors dissolution progress and transitions pumps between operational states, making the system adaptive rather than static to prevent uncontrolled backflow while maintaining high dissolution rates
Solution Approach 2:
The drain line acts as an intermediary pathway that provides controlled flow management. By routing washing liquid through the drain line with controlled liquid levels, the system mediates between the recirculation function (dissolution enhancement) and the need to prevent uncontrolled backflow, creating a buffer zone for safe detergent dissolution
2Productivity
If pump capacity is reduced to create convection and prevent backflow, then dissolution is improved, but pumping efficiency decreases
Solution Approach 1:
The system employs periodic action by alternating between recirculation pumping (at reduced capacity for convection) and drain pumping (at higher capacity for removal). This periodic switching allows the system to achieve both goals: enhanced dissolution during recirculation phases and efficient liquid removal during drain phases, preventing continuous operation at reduced efficiency
3Ease of manufacture
If washing liquid is pumped into the drain line or transfer line, then self-cleaning of pump device and fluid pathways is achieved, but liquid level control becomes more complex
Solution Approach 1:
The system implements self-service through automatic self-cleaning functionality. The pump device and fluid pathways clean themselves by pumping washing liquid through them during normal operation, eliminating the need for separate manual cleaning mechanisms or disassembly procedures, thereby simplifying maintenance despite control complexity
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 enhances the dissolution rate of laundry care substances through convection, preventing damage and discoloration by ensuring complete dissolution and self-cleaning of the pump device and liquid flow paths, while avoiding uncontrolled backflow and detergent residue issues.
Implementation Method 1
This dissolution process occurs primarily through diffusion and therefore requires a certain amount of time. This time can be shortened by agitating the water within the wash tub, for example, through drum rotation, thus also incorporating convection into the dissolution process.
Implementation Method 2
GB 2 099 462 A discloses a washing machine designed to prevent excessive consumption of laundry care products. The washing machine is configured to briefly and intermittently activate a pump during the washing process to pump washing liquid containing the laundry care product into a drain hose. The washing liquid in the drain hose alternately rises and falls, thereby dissolving the laundry care product.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention relates to a laundry care appliance (100) with a tub (105) for receiving washing liquid, wherein the tub (105) has a drain opening (109) and an inlet element (111), a pump device (115) for pumping the washing liquid, a drain line (113) which fluidically connects the drain opening (109) to the pump device (115), a pumping line (117) which fluidly connects the pump device (115) to an external area (119) of the laundry care appliance (100), wherein the pump device (115) has a first pump (125-1) which is configured to pump washing liquid from the tub (105) through the drain opening (109), through the drain line (113) and through the pumping line (117) out of the laundry care appliance (100), and a control unit (133) for controlling the pump device. (115), wherein the control (133) is designed,The first pump (125-1) of the pumping device (115) is activated to pump the washing liquid in order to pump washing liquid up to a liquid level (135-1) in the drain line (117). The laundry care device (100) is further equipped with a transfer line (123) which fluidically connects the pumping device (115) to the inlet element (111), wherein the pumping device (115) has a second pump (125-2) which is configured to pump washing liquid from the washing container (105) through the drain opening (109) and through the drain line (113) into the transfer line (123) and to return the washing liquid from the transfer line (123) and through the inlet element (111) to the washing container (105). The control unit (133) is configured to activate one of the pumps (125-1, 125-2) of the pumping device (115) for pumping the washing liquid in a first time period (143-1),to pump washing liquid up to the liquid level (135-1) in the drain line (117) or up to a liquid level (135-2) in the transfer line (123). Furthermore, the control unit (133) is configured to activate the other of the pumps (125-1, 125-2) of the pumping device (115) to pump the washing liquid in a second time period (143-2) following the first time period (143-1), in order to pump the washing liquid from the respective drain line (117) or transfer line (123) and to pump the pumped washing liquid up to a liquid level (135-1, 135-2) in the respective other of the drain line (117) or transfer line (123). The invention also relates to a method (200) for operating such a laundry care device (100).