Washing machine appliance out-of-balance detection

Patent metadata

Field	Value
Publication number	US-10000877-B2
Application number	US-201615099745-A
Country	US
Kind code	B2
Filing date	Apr 15, 2016
Priority date	Apr 15, 2016
Publication date	Jun 19, 2018
Grant date	Jun 19, 2018

Abstract

A method for operating a washing machine appliance includes flowing a volume of liquid into a tub, and agitating articles within the tub for a first period and using a first agitation profile, the tub containing the volume of liquid. The method further includes measuring movement of the tub during agitation of the articles within the tub, wherein the step of measuring movement occurs after agitating articles within the tub for the first period and for an intermediate measurement period and using an intermediate agitation profile, and wherein the intermediate agitation profile is different from the first agitation profile. The method further includes agitating articles within the tub for a second period when the final measured movement is greater than an out-of-balance movement threshold. The method further includes draining liquid from the tub when the final measured movement is less than the out-of-balance movement threshold.

First claim

What is claimed is:

1. A method for operating a washing machine appliance, the washing machine appliance having a tub and a basket rotatably mounted within the tub, the basket defining a chamber for receipt of articles for washing, the method comprising:
flowing a volume of liquid into the tub;
agitating articles within the tub for a first period and using a first agitation profile, the tub containing the volume of liquid;
measuring movement of the tub during agitation of the articles within the tub, wherein the step of measuring movement occurs after agitating articles within the tub for the first period and for an intermediate measurement period using an intermediate agitation profile, and wherein the intermediate agitation profile is different from the first agitation profile;
agitating articles within the tub for a second period when the final measured movement is greater than an out-of-balance movement threshold;
draining liquid from the tub when the final measured movement is less than the out-of-balance movement threshold; and
spinning the basket after draining liquid from the tub,
wherein agitating articles within the tub comprises redistributing the articles during a tumbling cycle within the tub through a repeated starting-stopping pattern of agitation strokes according to a corresponding agitation profile prior to the draining liquid from the tub.

2. The method of claim 1 , wherein the first agitation profile and the intermediate agitation profile are each defined by an acceleration rate, an acceleration duration, stroke duration, a dwell time between strokes, and a stroke direction pattern.

3. The method of claim 2 , wherein a maximum acceleration rate for the intermediate agitation profile is greater than a maximum acceleration rate for the first agitation profile.

4. The method of claim 2 , wherein the stroke duration for the intermediate agitation profile is between one-quarter and one-third of a natural frequency of the tub relative to a cabinet of the washing machine appliance.

5. The method of claim 2 , wherein a total stroke distance for the intermediate agitation profile is between 60 degrees and 150 degrees.

6. The method of claim 2 , wherein the stroke direction pattern for the intermediate agitation profile comprises a plurality of successive strokes in a single direction with no intervening strokes in an opposite direction.

7. The method of claim 6 , wherein the dwell time for the intermediate agitation profile is selected such that the successive strokes occur at a rate of between 75% and 133% of the time period of the first mode natural frequency.

8. The method of claim 6 , wherein the dwell time for the intermediate agitation profile is selected such that the successive strokes occur at a rate of between 38% and 67% of the time period of the first mode natural frequency.

9. The method of claim 2 , wherein the stroke direction pattern for the intermediate agitation profile comprises a plurality of successive strokes each in an opposite direction of the preceding stroke.

10. The method of claim 1 , wherein the first agitation profile is used during the step of agitating articles within the tub for the second period.

11. The method of claim 1 , wherein a second agitation profile is used during the step of agitating articles within the tub for the second period, the second agitation profile different from the first agitation profile and intermediate agitation profile.

12. The method of claim 1 , wherein, during the step of measuring movement, agitating of the articles is actively ceased upon determination that the measured movement is less than the out-of-balance movement threshold.

13. A washing machine appliance, comprising:
a tub;
a basket rotatably mounted within the tub, the basket defining a wash chamber for receipt of articles for washing;
a valve;
a nozzle configured for flowing liquid from the valve into the tub;
an agitation element;
a measurement device;
a motor in mechanical communication with the basket, the motor configured for selectively rotating the basket within the tub and further configured for selectively rotating the agitation element; and
a controller in operative communication with the valve, the motor and the measurement device, the controller configured for:
flowing a volume of liquid into the tub;
agitating articles within the tub for a first period and using a first agitation profile, the tub containing the volume of liquid;
measuring movement of the tub during agitation of the articles within the tub, wherein the step of measuring movement occurs after agitating articles within the tub for the first period and for an intermediate measurement period using an intermediate agitation profile, and wherein the intermediate agitation profile is different from the first agitation profile;
agitating articles within the tub for a second period when the final measured movement is greater than an out-of-balance movement threshold;
draining liquid from the tub when the final measured movement is less than the out-of-balance movement threshold; and
spinning the basket after draining liquid from the tub,
wherein agitating articles within the tub comprises redistributing the articles during a tumbling cycle within the tub through a repeated starting-stopping pattern of agitation strokes according to a corresponding agitation profile prior to the draining liquid from the tub.

14. The washing machine appliance of claim 13 , wherein the first agitation profile and the intermediate agitation profile are each defined by an acceleration rate, an acceleration duration, stroke duration, a dwell time between strokes, and a stroke direction pattern.

15. The washing machine appliance of claim 14 , wherein a maximum acceleration rate for the intermediate agitation profile is greater than a maximum acceleration rate for the first agitation profile.

16. The washing machine appliance of claim 14 , wherein the stroke duration for the intermediate agitation profile is between one-quarter and one-third of a natural frequency of the tub relative to a cabinet of the washing machine appliance.

17. The washing machine appliance of claim 14 , wherein a total stroke distance for the intermediate agitation profile is between 60 degrees and 150 degrees.

18. The washing machine appliance of claim 14 , the stroke direction pattern for the intermediate agitation profile comprises a plurality of successive strokes in a single direction with no intervening strokes in an opposite direction.

19. The washing machine appliance of claim 13 , wherein the first agitation profile is used during the step of agitating articles within the tub for the second period.

20. The washing machine appliance of claim 13 , wherein a second agitation profile is used during the step of agitating articles within the tub for the second period, the second agitation profile different from the first agitation profile and intermediate agitation profile.

Assignees

• Gen Electric
• Haier Us Appliance Solutions Inc

Inventors

• Davis Paul Owen
• Dunn David Scott
• Dedow Gregory

Classifications

• D06F23/04

  and rotating or oscillating about a vertical axis · CPC title

• D06F37/12

  adapted for rotation or oscillation about a vertical axis · CPC title

• G01M1/16

  by oscillating or rotating the body to be tested · CPC title

• D06F37/203 Primary

  Textiles & Paper · mapped topic

• D06F35/005

  Methods for washing, rinsing or spin-drying · CPC title