Laundry treating appliances and methods of controlling the same to balance small loads

Abstract

Laundry treating appliances and methods of controlling the same to balance small loads are disclosed. An example method of operating a laundry treating appliance having a rotating drum defining a treating chamber in which laundry is received for treatment according to at least one cycle of operation, and at least one balancing ring to counteract an imbalance of the rotating drum includes determining whether a small load is present in the treating chamber, substantially aligning the small load and a moveable mass of the balancing ring(s) when the drum is substantially stationary, and accelerating rotation of the drum based on a viscosity of fluid in the balancing ring(s) to position the small load substantially opposite the moveable mass.

What is claimed is: 
     
         1 . A method of operating a laundry treating appliance having a rotating drum defining a treating chamber in which laundry is received for treatment according to at least one cycle of operation, and a balancing ring to counteract an imbalance of the rotating drum, the method comprising:
 determining whether a small load is present in the treating chamber;   substantially aligning the small load and a moveable mass of the balancing ring when the drum is substantially stationary; and   accelerating rotation of the drum based on a viscosity of fluid in the balancing ring to position the small load substantially opposite the moveable mass.   
     
     
         2 . A method as defined in  claim 1 , wherein the moveable mass comprises the fluid. 
     
     
         3 . A method as defined in  claim 1 , wherein the drum is accelerated such that the small load and the moveable mass are substantially opposite at and above a critical rotation speed of the drum. 
     
     
         4 . A method as defined in  claim 3 , wherein the critical rotation speed corresponds to a natural resonant frequency of a suspension system. 
     
     
         5 . A method as defined in  claim 3 , wherein the critical rotation speed is between about 70 to 250 revolutions-per-minute. 
     
     
         6 . A method as defined in  claim 1 , further comprising:
 determining a temperature of the fluid; and   determining the viscosity of the fluid based on the determined temperature.   
     
     
         7 . A method as defined in  claim 6 , wherein determining the temperature of the fluid comprises measuring the temperature of the fluid. 
     
     
         8 . A method as defined in  claim 6 , further comprising determining a temperature of a second fluid in the drum, wherein the temperature of the fluid in the balancing ring is determined based on the determined temperature of the second fluid. 
     
     
         9 . A method as defined in  claim 6 , further comprising determining a motor temperature, wherein the temperature of the fluid in the balancing ring is determined based on the determined motor temperature. 
     
     
         10 . A method as defined in  claim 6 , further comprising determining an ambient temperature, wherein the temperature of the fluid in the balancing ring is determined based on the determined ambient temperature. 
     
     
         11 . A method as defined in  claim 1 , further comprising determining an energy input to the balance ring over a predetermined time period, wherein the viscosity of the fluid is determined based on the estimated energy. 
     
     
         12 . A method as defined in  claim 11 , further comprising determining the energy input based on a number of cycles operated over a given period of time. 
     
     
         13 . A method as defined in  claim 11 , further comprising determining at least one of a mechanical or an electrical energy input into the laundry treating appliance, wherein the energy input to the balance ring is determined based on the at least one of the mechanical or the electrical energy input into the laundry treating appliance. 
     
     
         14 . A method as defined in  claim 1 , further comprising accelerating rotation of the drum according to a ramp profile selected from a plurality of ramp profiles based on the estimated viscosity of the fluid. 
     
     
         15 . A method as defined in  claim 14 , wherein the plurality of ramp profiles correspond to respective ones of a plurality of viscosities. 
     
     
         16 . A method as defined in  claim 1 , further comprising:
 stopping a rotation of the drum; and   holding the drum substantially stationary to allow the moveable mass and the small load to substantially align.   
     
     
         17 . A method as defined in  claim 1 , wherein determining whether the small load is present comprises comparing at least one of a weight or a volume of the small load to a threshold. 
     
     
         18 . A method as defined in  claim 1 , wherein determining whether the small load is present comprises receiving a user input. 
     
     
         19 . A method of operating a laundry treating appliance having a rotating drum defining a treating chamber in which laundry is received for treatment according to at least one cycle of operation, and a balancing ring to counteract an imbalance of the rotating drum, the method comprising:
 determining a position of a moveable mass of the balancing ring; and   accelerating rotation of the drum based on a viscosity of fluid in the balancing ring, a location of a small load in the treating chamber, and the detected position to position the small load substantially opposite the moveable mass at and above a critical rotation speed of the drum.   
     
     
         20 . A method as defined in  claim 19 , further comprising determining the location of the small load in the treating chamber; 
     
     
         21 . A method as defined in  claim 19 , further comprising:
 determining a temperature of the fluid; and   determining the viscosity of the fluid based on the determined temperature.   
     
     
         22 . A method as defined in  claim 19 , further comprising accelerating the rotation of the drum according to a ramp profile selected from a plurality of ramp profiles based on the viscosity of the fluid. 
     
     
         23 . A method as defined in  claim 22 , wherein the plurality of ramp profiles correspond to respective ones of a plurality of viscosities. 
     
     
         24 . A laundry treating appliance comprising:
 a rotating drum defining a treating chamber in which laundry is received for treatment according to at least one cycle of operation;   a balancing ring coupled with the rotating drum to counteract an imbalance of the rotating drum;   a controller configured to determine whether a small load is present in the treating chamber, substantially align the small load and a moveable mass of the balancing ring when the rotating drum is substantially stationary, and accelerate rotation of the drum based on an estimated temperature of fluid in the balancing ring to position the small load substantially opposite the moveable mass at and above a critical rotation speed of the drum.   
     
     
         25 . A laundry treating appliance as defined in  claim 24 , further comprising a sensor to determine a presence of the small load in the treating chamber. 
     
     
         26 . A laundry treating appliance as defined in  claim 24 , wherein the controller is to determine whether the small load is present in the treating chamber based on a user input. 
     
     
         27 . A laundry treating appliance as defined in  claim 24 , wherein the critical rotation speed corresponds to a natural resonant frequency of a suspension system as the drum is rotated. 
     
     
         28 . A laundry treating appliance as defined in  claim 24 , wherein the controller is to:
 determine the temperature of the fluid; and   select a ramp profile from a plurality of ramp profiles based on the determined temperature; and   accelerate rotation of the drum according to the ramp profile.