Method of determining whether process water is present in a circulation pump of an appliance for washing and rinsing goods, and appliance and computer program therewith

Patent metadata

Field	Value
Publication number	US-10595703-B2
Application number	US-201515772214-A
Country	US
Kind code	B2
Filing date	Nov 10, 2015
Priority date	Nov 10, 2015
Publication date	Mar 24, 2020
Grant date	Mar 24, 2020

Abstract

Provided herein is a method of determining whether process water is present in a circulation pump of an appliance for washing and rinsing goods, and an appliance performing the method. The method of determining whether process water is present in a circulation pump of an appliance for washing and rinsing goods may include measuring a minimum value of a property representing load of the circulation pump at a predetermined first speed, measuring a maximum value of a property representing load of the circulation pump at a predetermined second speed, the second speed being higher than the first speed, determining a relation between said minimum value and said maximum value, and determining, from said relation, whether process water is present in the circulation pump.

First claim

The invention claimed is:

1. A method of determining whether process water is present in a circulation pump of an appliance for washing and rinsing goods, comprising:
measuring a minimum value of a property representing load of the circulation pump at a predetermined first speed (v 1 );
measuring a maximum value of a property representing load of the circulation pump at a predetermined second speed (v 2 ), the second speed being higher than the first speed;
determining a relation between said minimum value and said maximum value; and
determining, from said relation, whether process water is present in the circulation pump.

2. The method of claim 1 , the measuring of the minimum and maximum value comprising:
measuring a minimum value of operating current (I(v 1 ) min ) of the circulation pump at the predetermined first speed (v 1 ); and
measuring a maximum value of operating current (I(v 2 ) max ) of the circulation pump at the predetermined second speed (v 2 ).

3. The method of claim 1 , the determining of the relation between said minimum value and said maximum load comprising:
calculating a difference (Δ) between said minimum value and said maximum value.

4. The method of claim 3 , the determining whether process water is present in the circulation pump comprising:
determining whether the calculated difference (Δ) exceeds a predetermined threshold value (T), wherein process water is indicated to be present in the circulation pump.

5. The method of claim 1 , the determining of the relation between said minimum value and said maximum value comprising:
calculating a quotient (p, q) between said minimum value and said maximum value.

6. The method of claim 5 , the quotient (q) being calculated by dividing the value representing maximum load with the value representing minimum load; the determining whether process water is present in the circulation pump comprising:
determining whether the calculated quotient (q) exceeds a predetermined threshold value (T), wherein process water is indicated to be present in the circulation pump.

7. The method of claim 5 , the quotient (p) being calculated by dividing the value representing minimum load with the value representing maximum load; the determining whether process water is present in the circulation pump comprising:
determining whether the calculated quotient (p) is below a predetermined threshold value (T), wherein process water is indicated to be present in the circulation pump.

8. An appliance for washing and rinsing goods, comprising:
a circulation pump;
a sensing arrangement arranged to measure a minimum value of a property representing load of the circulation pump at a predetermined first speed (v 1 ), and a maximum value of a property representing load of the circulation pump at a predetermined second speed (v 2 ), the second speed being higher than the first speed;
a controller arranged to control the speed of the circulation pump, wherein the controller further is arranged to
determine a relation between said minimum value and said maximum value; and
determine, from said relation, whether process water is present in the circulation pump.

9. The appliance of claim 8 , the sensing arrangement further being arranged to, when measuring the minimum and maximum value:
measure a minimum value of operating current (I(v 1 ) min ) of the circulation pump at the predetermined first speed (v 1 ); and
measure a maximum value of operating current (I(v 2 ) max ) of the circulation pump at the predetermined second speed (v 2 ).

10. The appliance of claim 8 , the controller further being arranged to, when determining the relation between said minimum value and said maximum value comprising:
calculating a difference (Δ) between said minimum value and said maximum value.

11. The appliance of claim 10 , the controller further being arranged to, when determining whether process water is present in the circulation pump:
determine whether the calculated difference (Δ) exceeds a predetermined threshold value (T), wherein process water is indicated to be present in the circulation pump.

12. The appliance of claim 8 , the controller further being arranged to, when determining the relation between said minimum value and said maximum value:
calculate a quotient (p, q) between said minimum value and said maximum value.

13. The appliance of claim 12 , the controller further being arranged to:
calculate the quotient (q) by dividing the value representing maximum load with the value representing minimum load; and further to, when determining whether process water is present in the circulation pump:
determine whether the calculated quotient (q) exceeds a predetermined threshold value (T), wherein process water is indicated to be present in the circulation pump.

14. The appliance of claim 12 , the controller further being arranged to:
calculate the quotient (p) by dividing the value representing minimum load with the value representing maximum load; and further to, when determining whether process water is present in the circulation pump:
determine whether the calculated quotient (p) is below a predetermined threshold value (T), wherein process water is indicated to be present in the circulation pump.

15. The appliance of claim 8 , the sensing arrangement being arranged to measure the value of a property representing circulation pump load by measuring a value of operating current of a motor driving the circulation pump.

16. The appliance of claim 15 , wherein the sensing arrangement comprises:
a resistor arranged at the motor driving the circulation pump, through which resistor the operating current of the motor is measured.

17. A computer program comprising computer-executable instructions for causing a device to perform steps recited in claim 1 when the computer-executable instructions are executed on a processing unit included in the device.

18. A computer program product comprising a computer readable medium, the computer readable medium having the computer program according to claim 17 embodied thereon.

19. The appliance of claim 8 , said appliance comprising a dish washer or a washing machine.

Assignees

• Electrolux Appliances AB

Inventors

• Persson David

Classifications

• A47L15/0049

  Detection or prevention of malfunction, including accident prevention (arrangements to prevent clogging of filters A47L15/4208; safety arrangements for preventing water damage A47L15/421) · CPC title

• F04D15/0088

  Testing machines · CPC title

• A47L15/4225

  Arrangements or adaption of recirculation or discharge pumps · CPC title

• F04D15/0245

  responsive to a condition of the pump · CPC title

• A47L2401/14

  Water pressure or flow rate · CPC title