Drain Pump Duty-Cycle Control to Prevent Cavitation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional electric home appliances with drain functions face inefficiencies due to cavitation issues, leading to prolonged drain times and incomplete water removal, especially when installation conditions create air spaces and increased water pressure.
Innovation Solution
A method and apparatus that control the drain pump by alternating ON/OFF cycles based on a predetermined duty ratio, with a controller switching the pump on and off to minimize cavitation, using a check valve to prevent residual water from flowing back and ensuring the pump discharges air before continuous operation, thereby optimizing drain efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the drain pump is continuously operated to drain water, then the drain operation is performed, but cavitation occurs due to air space and increased water pressure, extending the draining time
Solution Approach 1:
The drain pump operates in periodic cycles rather than continuously. The controller alternates between turning the pump on and off at predetermined intervals, allowing cavitation to be minimized during off periods while maintaining drainage progress during on periods. This periodic operation resolves the contradiction by preventing cavitation buildup that would otherwise extend total draining time.
Solution Approach 2:
The system performs preliminary air discharge action before continuous water drainage. The pump initially operates to discharge air from the drain passage and housing, then pauses to prevent cavitation, before resuming operation. This preliminary air removal action prepares the system for efficient subsequent drainage without cavitation-related delays.
2Quantity of substance
If the drain pump operates continuously, then water drainage is achieved, but air space in the drain-pump housing causes cavitation that prevents substantial water drainage
Solution Approach 1:
The controller monitors drain operation status and uses feedback to determine when to switch the pump between on and off states. By detecting conditions such as air discharge completion and water level changes, the controller adjusts pump operation to maintain reliable drainage while preventing cavitation that would compromise operational reliability.
Solution Approach 2:
Periodic pump operation with predetermined on/off cycles allows the system to reliably discharge water while minimizing cavitation. The regular interruption of operation prevents air space accumulation that would otherwise cause unreliable drainage, ensuring consistent water removal performance.
3Ease of operation
If the drain pump is switched on according to conventional steps, then the drain operation starts, but the operation time becomes longer due to cavitation
Solution Approach 1:
The simplified periodic control method automatically switches the pump on and off at predetermined intervals without complex user intervention. This maintains ease of operation while the periodic cycles prevent cavitation, thereby reducing total pump operation time compared to conventional continuous operation that encounters cavitation-related delays.
Solution Approach 2:
The system performs self-regulated periodic operation where the controller automatically manages pump on/off timing based on predetermined duty ratios. This self-service control simplifies operation while the built-in periodic cycles inherently prevent cavitation, reducing overall operation time without requiring external intervention or complex user programming.
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 approach reduces the influence of cavitation, shortens the drain time, and ensures complete water removal, enhancing the appliance's throughput by preventing faulty operations and unnecessary pump usage.
Implementation Method 1
a drain pump draining water from the water tub
Implementation Method 2
a check valve mounted to one side of the drain pump and preventing residual water of the drain pump from flowing backward
Implementation Method 3
a water-level detector detecting a water level of the water tub
Data Source
AI summary
A home appliance equipped with a drain function and a method of controlling the same are disclosed. A method of controlling a home appliance equipped with a drain apparatus includes switching ON/OFF the drain apparatus during a first time, switching on the drain apparatus during a second time after switching ON/OFF the drain apparatus, checking a variation of the water level according to a draining status, and controlling the drain apparatus based on the checked water-level variation result corresponding to the draining status.