Appliance with turbidity sensor assisted time interval determination

Abstract

The present subject matter provides an appliance with features for determining a time interval for liquid flowing into and/or out of the appliance. For example, a flow of liquid into and/or out of a wash chamber of the appliance is initiated, and a first time is noted. A turbidity sensor is monitored until the sensor detects liquid or air respectively, and a second time is logged. A time interval is calculated based at least in part on the first time and the second time.

What is claimed is: 
     
         1 . A dishwasher appliance comprising:
 a cabinet defining a wash chamber, said cabinet including a sump positioned adjacent a bottom of said cabinet, the sump configured for collecting liquid in the wash chamber;   a rack assembly slidably received into the wash chamber and configured for receipt of articles for cleaning;   a spray arm assembly for applying the liquid to the articles in said rack assembly;   an inlet configured for selectively adding liquid to the wash chamber of said cabinet;   a turbidity sensor disposed within the sump of said cabinet and configured for measuring a turbidity of fluid in the sump; and   a processing device in communication with said inlet and said turbidity sensor, wherein said processing device is configured for:
 adjusting said inlet in order to initiate the flow of liquid into the wash chamber of said cabinet; 
 noting a first time, t 1 , that corresponds to said step of adjusting; 
 detecting liquid with said turbidity sensor; 
 logging a second time, t 2 , that corresponds to said step of detecting; and 
 determining a time interval based at least in part on t 1  and t 2 . 
   
     
     
         2 . The dishwasher appliance of  claim 1 , wherein said processing device is further configured for calculating a fluid flow rate based at least in part on t 1  and t 2 . 
     
     
         3 . The dishwasher appliance of  claim 2 , wherein said processing device is further configured for comparing the fluid flow rate to a stored fluid flow rate. 
     
     
         4 . The dishwasher appliance of  claim 3 , wherein said processing device is further configured for replacing the stored fluid flow rate with the fluid flow rate if the stored fluid flow rate is significantly different from the fluid flow rate. 
     
     
         5 . The dishwasher appliance of  claim 1 , wherein said processing device is further configured for repeating said steps of adjusting, noting, detecting, and logging in order to generate a plurality of t 1  and a plurality of t 2 , said processing device determining the time interval based at least in part on the plurality t 1  and the plurality of t 2 . 
     
     
         6 . The dishwasher appliance of  claim 1 , further comprising a drain configured for draining the sump of said cabinet of liquid, wherein said processing device is further configured for:
 opening said drain in order to initiate a flow of the liquid out of the sump of said cabinet;   recording an additional first time, t 1a , that corresponds to about said step of opening;   sensing air with said turbidity sensor;   chronicling an additional second time, t 2a , that corresponds to about said step of sensing;   establishing an additional time interval based at least in part on t 1a  and t 2a .   
     
     
         7 . The dishwasher appliance of  claim 6 , wherein said processing device is further configured for computing an additional fluid flow rate based at least in part on t 1a  and t 2a . 
     
     
         8 . The dishwasher appliance of  claim 7 , wherein said processing device is further configured for comparing the additional fluid flow rate to an additional stored fluid flow rate. 
     
     
         9 . The dishwasher appliance of  claim 6 , wherein said processing device is further configured for repeating said steps of opening, recording, sensing, and chronicling in order to generate a plurality of t 1a  and a plurality of t 2a , said processing device determining the additional fluid flow rate based at least in part on the plurality of t 1a  and plurality of t 2a . 
     
     
         10 . A method for operating an appliance, the method comprising:
 initiating a flow of a liquid into a sump of the appliance;   noting a first time, t 1 , that corresponds to about said step of initiating;   detecting the liquid with a turbidity sensor;   logging a second time, t 2 , that corresponds to about said step of detecting; and   determining a time interval based at least in part upon t 1  and t 2 .   
     
     
         11 . The method of  claim 10 , further comprising calculating a fluid flow rate of the liquid based at least in part upon t 1  and t 2 . 
     
     
         12 . The method of  claim 11 , further comprising comparing the fluid flow rate to a prior fluid flow rate. 
     
     
         13 . The method of  claim 11 , further comprising replacing the prior fluid flow rate with the fluid flow rate if the prior fluid flow rate is significantly different from the fluid flow rate. 
     
     
         14 . The method of  claim 10 , further comprising:
 repeating said steps of adjusting, noting, detecting, and logging in order to generate a plurality of t 1  and a plurality of t 2 ; and   determining the time interval based at least in part on the plurality of t 1  and the plurality of t 2 .   
     
     
         15 . A method for operating an appliance, the method comprising:
 initiating a flow of a liquid out of a sump of the appliance;   noting a first time, t 1 , that corresponds to about said step of initiating;   detecting air with a turbidity sensor;   logging a second time, t 2 , that corresponds to about said step of detecting; and   determining a time interval based at least in part upon t 1  and t 2 .   
     
     
         16 . The method of  claim 15 , further comprising calculating a fluid flow rate of the liquid based at least in part upon t 1  and t 2 . 
     
     
         17 . The method of  claim 16 , further comprising comparing the fluid flow rate to a prior fluid flow rate. 
     
     
         18 . The method of  claim 16 , further comprising replacing the prior fluid flow rate with the fluid flow rate if the prior fluid flow rate is significantly different from the fluid flow rate. 
     
     
         19 . The method of  claim 15 , further comprising:
 repeating said steps of initiating, noting, detecting, and logging in order to generate a plurality of t 1  and a plurality of t 2 ; and   determining the time interval based at least in part on the plurality of t 1  and the plurality of t 2 .