Method of using turbidity measurements to improve performance of a washing machine appliance

Abstract

A washing machine appliance includes a wash basket that is rotatably mounted within a wash tub. A water supply is provided for selectively adding wash fluid to the wash tub, a motor assembly is mechanically coupled to the wash basket for selectively rotating the wash basket, and a turbidity sensor is positioned within the wash fluid. A controller is configured to operate the water supply to dispense a target volume of the wash fluid, perform an additive mixing cycle to agitate wash additive within the target volume of the wash fluid, obtain a first turbidity measurement, perform an agitation cycle with the target volume of the wash fluid, obtain a second turbidity measurement, and complete a wash cycle at the a wash cycle intensity determined a based at least in part on the first turbidity and the second turbidity.

What is claimed is: 
     
         1 . A washing machine appliance, comprising:
 a wash tub positioned within a cabinet;   a wash basket rotatably mounted within the wash tub and defining a wash chamber configured for receiving a load of clothes;   a water supply for selectively adding wash fluid to the wash tub;   a sump positioned proximate a bottom of the wash tub for collecting the wash fluid;   a turbidity sensor positioned within the wash fluid;   a motor assembly mechanically coupled to the wash basket for selectively rotating the wash basket; and   a controller operably coupled to the water supply and the motor assembly, the controller being configured to:
 operate the water supply to dispense a target volume of the wash fluid into the wash tub; 
 operate the motor assembly to perform an additive mixing cycle to agitate wash additive within the target volume of the wash fluid; 
 obtain a first turbidity of the wash fluid using the turbidity sensor; 
 operate the motor assembly to perform an agitation cycle with the target volume of the wash fluid; 
 obtain a second turbidity of the wash fluid using the turbidity sensor; 
 determine a wash cycle intensity based at least in part on the first turbidity and the second turbidity; and 
 complete a wash cycle at the determined wash cycle intensity. 
   
     
     
         2 . The washing machine appliance of  claim 1 , wherein the target volume is determined based at least in part using a load sensing procedure. 
     
     
         3 . The washing machine appliance of  claim 1 , wherein the agitation cycle has an agitation duration and the additive mixing cycle has a mixing duration, and wherein the agitation duration is at least 10 times longer than the mixing duration. 
     
     
         4 . The washing machine appliance of  claim 1 , wherein the additive mixing cycle has a mixing duration, the mixing duration being between about 5 seconds and 1 minute. 
     
     
         5 . The washing machine appliance of  claim 1 , wherein the agitation cycle and the additive mixing cycle have different agitation profiles or agitation intensities. 
     
     
         6 . The washing machine appliance of  claim 1 , wherein determining the wash cycle intensity based at least in part on the first turbidity and the second turbidity comprises:
 determining a turbidity difference between the first turbidity and the second turbidity; and   selecting the wash cycle intensity based at least in part on the turbidity difference.   
     
     
         7 . The washing machine appliance of  claim 1 , wherein the wash cycle intensity comprises:
 a cycle duration of the wash cycle.   
     
     
         8 . The washing machine appliance of  claim 1 , wherein the wash cycle intensity comprises:
 an agitation profile or an agitation intensity.   
     
     
         9 . The washing machine appliance of  claim 1 , wherein the controller is further configured to:
 determine that a user input comprises a smart wash cycle selection prior to operating the motor assembly to perform the additive mixing cycle.   
     
     
         10 . The washing machine appliance of  claim 9 , wherein the user input is received via a control panel of the wash machine appliance. 
     
     
         11 . The washing machine appliance of  claim 9 , wherein the controller is in operative communication with a remote device over a network, and wherein the user input is received via the remote device. 
     
     
         12 . The washing machine appliance of  claim 1 , wherein the controller is further configured to:
 determine that a normal wash cycle has been selected; and   perform a standard agitation cycle.   
     
     
         13 . The washing machine appliance of  claim 1 , wherein the turbidity sensor is positioned within the sump of the washing machine appliance. 
     
     
         14 . The washing machine appliance of  claim 1 , wherein the washing machine appliance is a vertical axis washing machine appliance. 
     
     
         15 . A method of operating a washing machine appliance, the washing machine appliance comprising a wash basket rotatably mounted within a wash tub, a water supply for selectively adding wash fluid to the wash tub, a turbidity sensor positioned within the wash fluid, and a motor assembly mechanically coupled to the wash basket for selectively rotating the wash basket, the method comprising:
 operating the water supply to dispense a target volume of the wash fluid into the wash tub;   operating the motor assembly to perform an additive mixing cycle to agitate wash additive within the target volume of the wash fluid;   obtaining a first turbidity of the wash fluid using the turbidity sensor;   operating the motor assembly to perform an agitation cycle with the target volume of the wash fluid;   obtaining a second turbidity of the wash fluid using the turbidity sensor;   determining a wash cycle intensity based at least in part on the first turbidity and the second turbidity; and   completing a wash cycle at the determined wash cycle intensity.   
     
     
         16 . The method of  claim 15 , wherein the target volume is determined based at least in part using a load sensing procedure. 
     
     
         17 . The method of  claim 15 , wherein the agitation cycle and the additive mixing cycle have different agitation profiles or agitation intensities. 
     
     
         18 . The method of  claim 15 , wherein determining the wash cycle intensity based at least in part on the first turbidity and the second turbidity comprises:
 determining a turbidity difference between the first turbidity and the second turbidity; and   selecting the wash cycle intensity based at least in part on the turbidity difference.   
     
     
         19 . The method of  claim 15 , further comprising:
 determining that a user input comprises a smart wash cycle selection prior to operating the motor assembly to perform the additive mixing cycle.   
     
     
         20 . The method of  claim 15 , further comprising:
 determining that a normal wash cycle has been selected; and   performing a standard agitation cycle.