# US 11,076,740 B2 · Method of controlling a circulation pump in an appliance for washing and rinsing goods > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,076,740 B2 - Document ID: US11076740B2 - Status: Granted - Kind: B2 - Application number: 15/759,031 - Filed: 2015-10-07 - Published: 2019-03-07 - Granted: 2021-08-03 - Earliest claimed: 2015-10-07 - Assignees: Electrolux Appliances Aktiebolag - Applicants: Electrolux Appliances Aktiebolag - Inventors: David Persson - Web page: https://patentgrep.com/patent/US11076740B2 ## CPC - A47L 15/0049: {Detection or prevention of malfunction, including accident prevention (arrangements to prevent clogging of filters A47L15/4208; safety arrangements for preventing water damage A47L15/421)} - A47L 15/4225: {Arrangements or adaption of recirculation or discharge pumps} - D06F 33/36: of washing - D06F 39/085: {Arrangements or adaptations of pumps} - A47L 2401/08: Drain or recirculation pump parameters, e.g. pump rotational speed or current absorbed by the motor - A47L 2401/14: Water pressure or flow rate - A47L 2501/01: Water supply, e.g. opening or closure of the water inlet valve - A47L 2501/04: Water pressure or flow rate - A47L 2501/05: Drain or recirculation pump, e.g. regulation of the pump rotational speed or flow direction - D06F 39/088: {Liquid supply arrangements} - D06F 2103/14: Supply, recirculation or draining of washing liquid - D06F 2103/18: Washing liquid level - D06F 2103/42: related to filters or pumps - D06F 2105/02: Water supply - D06F 2105/06: Recirculation of washing liquids, e.g. by pumps or diverting valves - Y02B 40/00: Technologies aiming at improving the efficiency of home appliances, e.g. induction cooking or efficient technologies for refrigerators, freezers or dish washers - A47L: DOMESTIC WASHING OR CLEANING (brushes A46B; cleaning quantities of bottles or of other hollow articles of one kind B08B9/00; laundry D06F); SUCTION CLEANERS IN GENERAL (cleaning in general B08) - D06F: LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES - Y02B: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS ## Abstract Provided herein are an appliance and method for washing and rinsing goods. The appliance may include a circulation pump, a sensing arrangement arranged to measure an indication of circulation pump pressure or process water flow rate through the circulation pump, and a controller arranged to control operating speed of the circulation pump. The controller may be further arranged to detect that the indicated circulation pump pressure or process water flow rate through the circulation pump is insufficient, and gradually reduce operating speed of the circulation pump until the circulation pump pressure or the process water flow rate through the circulation pump is at a sufficient operational level. ## Claims ### Claim 1 An appliance for washing and rinsing goods, comprising: a circulation pump; a sensing arrangement arranged to measure an indication of circulation pump pressure or process water flow rate through the circulation pump, wherein the sensing arrangement being arranged to measure operating current of a motor driving the circulation pump in order to attain an indication of circulation pump pressure or process water flow rate through the circulation pump; and a controller arranged to control operating speed of the circulation pump, wherein the controller further is configured to: detect that the indicated circulation pump pressure or process water flow rate through the circulation pump is insufficient; select a reduction process from the group consisting of (a) ramping down the operating speed of the circulation pump, (b) a stepwise reduction of the operating speed of the circulation pump comprising a plurality of reducing steps, and (c) a combination of ramping down the operation speed and stepwise reduction of the operating speed of the circulation pump; and reduce operating speed of the circulation pump via the selected reduction process until the indicated circulation pump pressure or the process water flow rate through the circulation pump is at a sufficient operational level (TOP). ### Claim 2 (depends on 1) The appliance of claim 1, the controller further being arranged to, when reducing the circulation pump operating speed: reduce the operating speed of the circulation pump; and determine whether the circulation pump pressure or the liquid flow rate through the circulation pump is at the sufficient operational level (TOP), wherein further reduction of the operating speed of the circulation pump is performed unless the sufficient operational level (TOP) is reached. ### Claim 3 (depends on 1) The appliance of claim 1, wherein the controller is arranged to perform a stepwise reduction of the operating speed of the circulation pump. ### Claim 4 (depends on 1) The appliance of claim 1, wherein the controller is arranged to perform a ramping down reduction of the operating speed of the circulation pump. ### Claim 5 (depends on 1) The appliance of claim 1, the controller further being arranged to: increase the operating speed of the circulation pump until the circulation pump pressure or process water flow rate trough the circulation pump is at a desired target operational level (TT) following the reduction of the operating speed of the circulation pump. ### Claim 6 (depends on 5) The appliance of claim 5, further comprising: an inlet for supplying water to the appliance; and a water supply valve for controlling the supply of water via the inlet, the controller further being arranged to control the water supply valve for supplying additional water to the appliance to increase circulation pump pressure or process water flow rate through the circulation pump, wherein the appliance is configured to supply the additional water to the appliance in an instance in which the controller is reducing the operating speed of the circulation pump. ### Claim 7 (depends on 5) The appliance of claim 5, wherein the controller is arranged to perform a stepwise increase of the operating speed of the circulation pump. ### Claim 8 (depends on 1) The appliance of claim 1, further comprising: an inlet for supplying water to the appliance; and a water supply valve for controlling the supply of water via the inlet, the controller further being arranged to control the water supply valve for supplying additional water to the appliance to increase circulation pump pressure or process water flow rate through the circulation pump. ### Claim 9 (depends on 1) The appliance of claim 1, said appliance comprising a dish washer or a washing machine. ### Claim 10 An appliance comprising a dish washer or a washing machine for washing and rinsing goods, comprising: a circulation pump; a sensing arrangement arranged to measure an indication of circulation pump pressure or process water flow rate through the circulation pump, wherein the sensing arrangement comprises a resistor arranged in a motor driving the circulation pump, through which resistor operating current of the motor is measured, in order to attain an indication of circulation pump pressure or process water flow rate through the circulation pump; and a controller arranged to control operating speed of the circulation pump, wherein the controller further is arranged to: detect that the indicated circulation pump pressure or process water flow rate through the circulation pump is insufficient; select a reduction process from the group consisting of (a) ramping down the operating speed of the circulation pump, (b) a stepwise reduction of the operating speed of the circulation pump comprising a plurality of reducing steps, and (c) a combination of ramping down the operation speed and stepwise reduction of the operating speed of the circulation pump; and to reduce operating speed of the circulation pump using the selected reduction process until the indicated circulation pump pressure or the process water flow rate through the circulation pump is at a sufficient operational level (TOP). ### Claim 11 (depends on 10) The appliance of claim 10, wherein reducing the operating speed of the circulation pump comprises alternating ramping down the operating speed of the circulation pump with stepwise reduction of the operating speed of the circulation pump.