Method and apparatus for balancing an unbalanced load in a washing machine

Patent metadata

Field	Value
Publication number	US-9428854-B2
Application number	US-84776510-A
Country	US
Kind code	B2
Filing date	Jul 30, 2010
Priority date	Jul 30, 2010
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

A washing machine including a suspension system is provided. The suspension system includes a wash tub, a basket rotatably coupled within the wash tub, and a drive and motor assembly. The washing machine further includes a controller configured initiate a spin cycle by increasing a spin speed of the basket to a target spin speed, identify an out-of-balance load prior to reaching the target spin speed, and limit the spin speed of the basket to a spin speed lower than a natural frequency of the suspension system for a predefined period of time.

First claim

What is claimed is:

1. A washing machine comprising:
a suspension system comprising a wash tub, a basket rotatably coupled within the wash tub and configured to receive a laundry load having a load size, and a drive and motor assembly, the suspension system defining a natural frequency that varies relative to the load size;
a sensing mechanism configured to detect an unbalanced load in the washing machine based in part on the natural frequency of the suspension system relative to the load size; and
a controller programmed to:
determine the natural frequency of the suspension system based on the particular suspension system and the size of the load;
initiate a spin cycle by increasing a spin speed of the basket to a target spin speed;
communicate with the sensing mechanism;
when an unbalanced load is detected by the sensing mechanism identify an out-of-balance load prior to reaching the target spin speed;
determine if a quantity of previous out-of-balance load redistribution attempts exceeds a redistribution attempt threshold level;
initiate an out-of-balance load redistribution if the quantity of previous out-of-balance load redistribution attempts has not exceeded the redistribution attempt threshold level;
increase the spin speed of the basket to the target spin speed after the out-of-balance load redistribution;
detect if the laundry load is out-of-balance with the sensing mechanism after increasing the spin speed of the basket; and
if the determined quantity of previous out-of-balance load redistribution attempts has exceeded the redistribution attempt threshold level, limit the spin speed of the basket to a limited spin speed lower than and based on the determined natural frequency of the suspension system corresponding to the load size for a predefined period of time.

2. A washing machine in accordance with claim 1 , wherein determining if the quantity of previous out-of-balance load redistribution attempts exceeds the redistribution attempt threshold level comprises:
determining the quantity of previous out-of-balance load redistribution attempts; and
comparing the determined quantity of previous out-of-balance load redistribution attempts to a redistribution attempt threshold level.

3. A washing machine in accordance with claim 1 , wherein the out-of-balance load redistribution comprises at least one of the following:
(i) limiting the spin speed of the basket to a spin speed lower than a natural frequency of the suspension system for a predefined period of time, and after the predefined period of time, increase the spin speed of the basket to the target spin speed;
(ii) executing a redistribution fill by adding a quantity of water to the wash tub and draining the quantity of water from the wash tub;
(iii) performing a redistribution agitation for a predefined period of time; and
(iv) adding a predefined quantity of water to the wash tub, and rotating the basket at a spin speed lower than the natural frequency of the suspension system.

4. A washing machine in accordance with claim 3 , wherein the quantity of water is based on a user defined setting.

5. A washing machine in accordance with claim 3 , wherein the quantity of water is a maximum quantity of water.

6. A washing machine in accordance with claim 1 , wherein the controller is further configured to initiate an out-of-balance load redistribution comprising adding a predefined quantity of water to the wash tub, and rotating the basket at a spin speed lower than the natural frequency of the suspension system corresponding to the load size.

7. A washing machine in accordance with claim 1 , wherein after limiting the spin speed of the basket to a spin speed lower than a natural frequency of the suspension system for a predefined period of time, the controller is further configured to increase the spin speed of the basket to the target spin speed.

8. A washing machine in accordance with claim 1 , wherein the sensing mechanism is further configured to measure the spin speed of the basket.

9. A washing machine in accordance with claim 1 , wherein the detecting of the unbalanced load in the washing machine is further based in part on the spin speed of the basket.

10. A washing machine in accordance with claim 1 , wherein the predefined period of time is greater than a standard spin time.

Assignees

• Dunn David Scott
• Root Steven Keith
• Saling Robert Anthony
• Koepke Steven Chadwick
• Ruiz Andres Guillermo
• Haier Us Appliance Solutions Inc

Inventors

• Dunn David Scott
• Root Steven Keith
• Saling Robert Anthony
• Koepke Steven Chadwick
• Ruiz Andres Guillermo

Classifications

• D06F2103/02

  Characteristics of laundry or load · CPC title

• D06F2058/2861

  Textiles & Paper · mapped topic

• D06F35/007

  for spin-drying only · CPC title

• D06F37/203

  Textiles & Paper · mapped topic

• D06F2204/086

  Textiles & Paper · mapped topic