Adaptive Automatic Laundry Washer Water Fill

• US 20080172804A1
• Filed: 01/18/2007
• Published: 07/24/2008
• Est. Priority Date: 01/18/2007
• Status: Active Grant

• Current Assignee: Electrolux Home Products Incorporated (AB Electrolux)
• Original Assignee: Electrolux Home Products Incorporated (AB Electrolux)
• Inventors: Piekarski, Marcelo, Bittencourt, Marcos Paulo Soares, Vanhazebrouck, Vicente Marconcin, Roepke, Jon, Ellingson, David Irwin
• Granted Patent: US 8,505,139 B2
• Time in Patent Office: Days
• US Class Current: 8/158
• CPC Class Codes: D06F 2103/02 Characteristics of laundry or load
• CPC Class Codes: D06F 2105/04 from separate hot and cold water inlets
• CPC Class Codes: D06F 33/34 of water filling
• CPC Class Codes: D06F 34/08 Control circuits or arrangements thereof
• CPC Class Codes: D06F 34/14 Arrangements for detecting or measuring specific parameters
• CPC Class Codes: D06F 39/08 Liquid supply or discharge arrangements supply of soap or other washing agents D06F39/02

Abstract

A washer fill system and method supply a suitable minimum amount of water necessary to wash a particular load of laundry based on readings taken from a pressure sensor that measures liquid pressure in the wash tub. During the fill period, water is initially sprayed over the load to evenly wet the clothes. As the clothes become saturated, excess free water collects at the bottom and begins to fill the tub. Pressure sensor readings are taken intermittently during the fill process to determine when a sufficient amount of free water for washing the load of clothes has accumulated in the tub. This includes pressure readings taken while pulsing the washer motor to spin the wash basket. Other pressure readings may be taken during a pause in filling to measure the water run-off from the wetted clothes above the free water line, and the release of air bubbles from a load portion below the water line. Determining the sufficiency of the amount of wash liquid in the wash tub involves implementation of an algorithm with coefficients determined through regression analyses, and may include other factors such as the water temperature and wash cycle setting for the laundry load. In another embodiment, pressure readings and associated calculations are used to determine a load size, which is in turn used to determine a time fill interval. The fill interval may be adjusted based upon determined water flow rates.

Claims

1. An automatic washing machine comprising:

a wash tub and nested wash basket;

a wash liquid supply flow path arranged to selectively flow wash liquid into said tub;

a pressure sensor configured to measure a liquid pressure in the wash tub;

a motor operably connected to rotate the wash basket in the wash tub; and

control circuitry, wherein the control circuitry is configured to control the washing machine to perform the steps of;

(a) adding wash liquid into the wash tub through the wash liquid supply flow path;

(b) rotating the wash basket with the motor following step (a);

(c) detecting a first liquid pressure within the wash tub using the pressure sensor during the rotation of the wash basket;

(d) determining whether there is a sufficient amount of wash liquid in the wash tub for any laundry load present in the wash basket, based at least in part on the detected first liquid pressure; and

(e) adding more wash liquid to the wash tub if it is determined in step (d) that there is an insufficient amount of wash liquid in the wash tub.

2. The washing machine of claim 1, wherein the amounts of wash liquid added to the wash tub in steps (a) and (e) are predetermined.

3. The washing machine of claim 1, wherein the determining step is carried out based in part on a user-selected wash temperature.

4. The washing machine of claim 1, wherein the determining step is carried out based in part on a user-selected wash cycle setting.

5. The washing machine of claim 1, wherein the determining step is carried out based in part on a flow rate for adding wash liquid into the wash tub.

6. The washing machine of claim 1, wherein a pause follows the addition of wash liquid to the tub and precedes the rotating of the wash basket, to allow the wash liquid in the wash tub to settle before said rotating.

7. The washing machine of claim 1, wherein in the event it is determined by the controller in step (d) that there is not a sufficient amount of wash liquid in the wash tub, steps (b) through (d) are repeated following step (e).

8. The washing machine of claim 1, further configured to detect a second liquid pressure within the wash tub before the rotating of the wash basket, and wherein the determining step comprises calculating a difference between the detected first and second liquid pressures.

9. The washing machine of claim 8, wherein the detected first liquid pressure is a minimum pressure occurring during the rotating of the wash basket.

10. The washing machine of claim 8, wherein the detected first liquid pressure is a maximum pressure occurring during the rotating of the wash basket.

11. The washing machine of claim 1, wherein the determining step is carried out based in part on a liquid pressure difference within the wash tub before and after an interval of draining wash liquid from the wash tub.

12. An automatic washing machine comprising:

a wash tub;

a wash liquid supply flow path arranged to selectively flow wash liquid into said tub;

a pressure sensor configured to measure a liquid pressure in the wash tub; and

control circuitry, wherein the control circuitry is configured to control the washing machine to perform the steps of;

(a) adding a first amount of wash liquid into the wash tub through said flow path, wherein adding the first amount of wash liquid results in the wetting of at least some portion of a load of laundry in the wash basket, and wherein after adding the wash liquid into the wash tub, a pool of free water has accumulated in the wash tub and at least some portion of the load of laundry is above the water line of the pool of free water;

(b) detecting a first liquid pressure within the wash tub using the pressure sensor;

(c) waiting an amount of time following step (b) during which some amount of wash liquid from the portion of the load above the water line has dropped down into the pool of free water and/or air bubbles have been released from a portion of the load below the water line;

(d) detecting a second liquid pressure within the wash tub using the pressure sensor, following step (c);

(e) determining whether there is a sufficient amount of wash liquid in the wash tub for the load of laundry, based at least in part on the detected first and second liquid pressures; and

(f) adding additional wash liquid to the wash tub if it is determined in step (e) that there is an insufficient amount of wash liquid in the wash tub.

13. The washing machine of claim 12, wherein the determining step is carried out based in part on a user-selected wash temperature.

14. The washing machine of claim 12, wherein the determining step is carried out based in part on a user-selected wash cycle setting.

15. The washing machine of claim 12, wherein a pause follows the addition of wash liquid to the tub and precedes the detecting of the first liquid pressure, to allow the wash liquid in the wash tub to settle before said detecting.

16. The washing machine of claim 12, wherein the determining step comprises calculating a pressure difference between the detected first and the second liquid pressures.

17. The washing machine of claim 12, further comprising a wash basket nested within said wash tub, and a motor operably connected to rotate the wash basket with the tub.

18. The washing machine of claim 17, wherein the step of adding a first amount of wash liquid comprises spinning the wash basket during the adding to better saturate the load.

19. The washing machine of claim 17, wherein the control circuitry is further configured to control the washing machine to perform the steps of:

rotating the wash basket with the motor; and

detecting a third liquid pressure within the wash tub using the pressure sensor during the rotation of the wash basket, wherein the determining of step (e) is further based on the detected third liquid pressure.

20. An automated method for filling a wash tub of an automatic washing machine, comprising the steps of:

(a) adding wash liquid into a wash tub;

(b) rotating a wash basket in the wash tub;

(c) detecting a first liquid pressure within the wash tub during the rotation of the wash basket;

(d) determining whether there is a sufficient amount of wash liquid in the wash tub for any laundry load present in the wash basket, based at least in part on the detected first liquid pressure; and

(e) adding more wash liquid to the wash tub if it is determined in step (d) that there is an insufficient amount of wash liquid in the wash tub.

21. The method of claim 20, wherein the amounts of wash liquid added to the wash tub in steps (a) and (e) are predetermined.

22. The method of claim 20, wherein the determining step is carried out based in part on a user-selected wash temperature.

23. The method of claim 20, wherein the determining step is carried out based in part on a user-selected wash cycle setting.

24. The method of claim 20, wherein the determining step is carried out based in part on a flow rate for adding wash liquid into the wash tub.

25. The method of claim 20, wherein a pause follows the addition of wash liquid to the tub and precedes the rotation of the wash basket, to allow the liquid in the tub to settle before said rotation.

26. The method of claim 20, wherein in the event it is determined in step (d) that there is not a sufficient amount of wash liquid in the wash tub, steps (b) through (d) are repeated following step (e).

27. The method of claim 20, further comprising detecting a second liquid pressure within the wash tub before the rotation of the wash basket, and wherein the determining step comprises calculating a difference between the detected first and second liquid pressures.

28. The method of claim 27, wherein the detected first liquid pressure is a minimum pressure occurring during the rotation of the wash basket.

29. The method of claim 27, wherein the detected first liquid pressure is a maximum pressure occurring during the rotation of the wash basket.

30. The method of claim 20, wherein the determining step is carried out based in part on a liquid pressure difference within the wash tub before and after an interval of draining wash liquid from the wash tub.

31. An automated method for filling a wash tub of an automatic washing machine, comprising the steps of:

(a) adding a first amount of wash liquid into a wash tub, wherein adding the first amount of wash liquid results in the wetting of at least some portion of a load of laundry in a wash basket in the wash tub, and wherein after adding the wash liquid into the wash tub, a pool of free water has accumulated in the wash tub and at least some portion of the load of laundry is above the water line of the pool of free water;

(b) detecting a first liquid pressure within the wash tub using a pressure sensor configured to measure liquid pressure in the wash tub;

(c) waiting an amount of time following step (b) during which some amount of water from the portion of the load above the water line has flowed down into the pool of free water and/or air bubbles have been released from a portion of the load below the water line;

(d) detecting a second liquid pressure within the wash tub using the pressure sensor, following step (c);

(e) determining whether there is a sufficient amount of wash liquid in the wash tub for the load of laundry based at least in part on the detected first and second liquid pressures; and

(f) adding additional wash liquid to the wash tub if it is determined in step (e) that there is an insufficient amount of wash liquid in the wash tub.

32. The method of claim 31, wherein the determining step is carried out based in part on a user-selected wash temperature.

33. The method of claim 31, wherein the determining step is carried out based in part on a user-selected wash cycle setting.

34. The method of claim 31, wherein a pause follows the addition of wash liquid to the tub and precedes the detecting of the first liquid pressure to allow the wash liquid in the wash tub to settle before said detecting.

35. The method of claim 31, wherein the determining step comprises calculating a pressure difference between the detected first and the second liquid pressures.

36. The method of claim 31, wherein the step of adding a first amount of wash liquid comprises spinning the wash load within the tub during the adding to better saturate the load.

37. An automatic washing machine comprising:

a wash tub;

a wash liquid supply flow path arranged to selectively flow wash liquid into said tub;

a pressure sensor configured to measure a liquid pressure in the wash tub; and

control circuitry, wherein the control circuitry is configured to control the washing machine to perform the steps of;

(a) detecting at least a first liquid pressure within the wash tub using the pressure sensor;

(b) determining a load size based upon the liquid pressure(s) detected in step (a);

(c) determining a flow rate of wash liquid added to the wash tub through said wash liquid supply flow path;

(d) calculating a wash tub fill time based on the load size determination of step (b), and the flow rate determined in step (c); and

(e) adding wash liquid to the wash tub through the wash liquid supply flow path for a duration of time equal to the wash tub fill time.

38. The washing machine of claim 37, wherein the step of determining the flow rate comprises determining a first flow rate from a cold water valve and determining a second flow rate from a hot water valve, and wherein the step of adding wash liquid comprises:

(i) calculating a cold water fill time based on the first flow rate;

(ii) calculating a hot water fill time based on the second flow rate, wherein the cold water fill time and hot water fill time add up to the calculated wash tub fill time;

(iii) opening the cold water valve for the cold water fill time, during which the hot water valve is not open; and

(iv) opening the hot water valve for the hot water fill time, during which the cold water valve is not open.

39. The washing machine of claim 38, wherein the cold water fill time and the hot water fill time are calculated based on a target temperature for the wash liquid.

40. The washing machine of claim 38, wherein steps (iii) and (iv) each occur in non-continuous subintervals, wherein every subinterval of opening one of the water valves is followed by a subinterval of opening the other water valve.

41. The washing machine of claim 37, wherein:

step (c) determines an updated flow rate based on at least one time and pressure measurement performed while adding water into the wash tub; and

step (d) calculates the wash tub fill time based on the updated flow rate.

42. An automated method for filling a wash tub of an automatic washing machine, comprising the steps of:

(a) detecting at least a first liquid pressure within a wash tub;

(b) determining a load size based upon the liquid pressure(s) detected in step (a);

(c) determining a flow rate for adding wash liquid into the wash tub;

(d) calculating a wash tub fill time based on the load size determination of step (b), and the flow rate determined in step (c); and

(e) adding wash liquid to the wash tub for a duration of time equal to the wash tub fill time.

43. The method of claim 42, wherein the step of determining the flow rate comprises determining a first flow rate from a cold water valve and determining a second flow rate from a hot water valve, and wherein the step of adding wash liquid comprises:

(i) calculating a cold water fill time based on the first flow rate;

(ii) calculating a hot water fill time based on the second flow rate, wherein the cold water fill time and hot water fill time add up to the calculated wash tub fill time;

(iii) opening the cold water valve for the cold water fill time, during which the hot water valve is not open; and

(iv) opening the hot water valve for the hot water fill time, during which the cold water valve is not open.

44. The method of claim 43, wherein the cold water fill time and the hot water fill time are calculated based on a target temperature for the wash liquid.

45. The method of claim 43, wherein steps (iii) and (iv) each occur in non-continuous subintervals, wherein every subinterval of opening one of the water valves is followed by a subinterval of opening the other water valve.

46. The method of claim 42, wherein:

step (c) determines an updated flow rate based on at least one time and pressure measurement performed while adding water to the wash tub; and

step (d) calculates the wash tub fill time based on the updated flow rate.