Ice maker with ice bin level control

Abstract

A clear ice maker unit has a clear ice maker mechanism with a cascading water evaporator configured to make clear ice during ice making cycles. A controller uses fuzzy logic to control the clear ice maker and determine whether to initiate a next ice making cycle based on input signals from a thermistor in the ice storage bin. The controller will prevent initiation of an ice making cycle when the ice bin is at or below a threshold temperature. The controller will also prohibit ice making when the ice bin is at or below a second, slightly higher temperature for more than a prescribed period of time. In this way, the clear ice maker can recognize an uneven distribution of ice and maintain an optimal amount of ice in the bin.

1 . An ice maker unit having an ice maker mechanism disposed in an ice maker chamber of an insulated cabinet, the ice maker mechanism being capable producing ice during a plurality of ice making cycles and depositing the ice into an ice bin within the cabinet, the ice maker unit comprising:
 a sensor disposed in the cabinet to sense the temperature at the ice bin; and   an electronic control having clock circuitry and fuzzy logic programming for controlling the ice maker mechanism, the control being electrically coupled to the sensor to receive an input signal from the sensor associated with a bin temperature, the control using the fuzzy logic programming to determine whether to initiate a next ice making cycle based on the bin temperature sensed by the sensor, wherein the control initiates the next ice making cycle only if first and second conditions are met, wherein in the first condition the bin temperature is above a first threshold temperature and in the second condition the bin temperature is not below a second threshold temperature for a prescribed time period.   
   
   
       2 . The ice maker unit of  claim 1 , wherein the sensor is disposed at a height corresponding to a maximum ice level in the ice bin. 
   
   
       3 . The ice maker unit of  claim 2 , wherein the second condition corresponds to an uneven ice distribution condition in which ice is disposed in the ice bin at or above the maximum ice level at only a portion of the ice bin. 
   
   
       4 . The ice maker unit of  claim 1 , wherein the first threshold temperature is essentially 33 degrees Fahrenheit and wherein the second threshold temperature is essentially 34 degrees Fahrenheit. 
   
   
       5 . The ice maker unit of  claim 1 , wherein the prescribed time period is set according to a time needed to complete a prescribed number of ice making cycles. 
   
   
       6 . The ice maker unit of  claim 5 , wherein the prescribed number of ice making cycles is three. 
   
   
       7 . The ice maker unit of  claim 1 , further comprising a user input connected to the control, wherein the first threshold temperature can be set by the user input. 
   
   
       8 . The ice maker unit of  claim 1 , wherein the ice maker unit includes a clear ice maker mechanism disposed in the ice maker chamber and capable of cascading water over a vertically disposed evaporator during a plurality of ice making cycles, each ice making cycle resulting in the production of a quantity of clear ice. 
   
   
       9 . The ice maker unit of  claim 1 , wherein the ice bin is not refrigerated. 
   
   
       10 . A clear ice maker unit, comprising:
 a cabinet defining an ice maker chamber and an ice storage bin;   a clear ice maker mechanism disposed in the ice maker chamber and capable of cascading water over a vertically disposed evaporator during a plurality of ice making cycles, each ice making cycle resulting in the production of a quantity of clear ice;   a controller configured to control the clear ice maker, the controller configured to determine whether to initiate a next ice making cycle; and   a sensor connected to the controller and disposed in the ice storage bin for sensing a bin temperature;   wherein the controller is configured to prevent the initiation of the next ice making cycle when the bin temperature is not above a first temperature and is less than or equal to a second temperature for a prescribed time period, wherein the second temperature is greater than the first temperature.   
   
   
       11 . The clear ice maker unit of  claim 10 , wherein the evaporator has a plurality of pockets therein, and wherein the clear ice maker mechanism is capable of cascading water over the evaporator during the plurality of ice making cycles and depositing clear ice formed on the evaporator into the ice storage bin. 
   
   
       12 . The clear ice maker unit of  claim 11 , wherein the sensor is disposed at a height corresponding to a maximum ice level in the ice bin. 
   
   
       13 . The clear ice maker unit of  claim 12 , wherein the second temperature is associated with an uneven ice distribution condition in which ice is disposed in the ice bin at or above the maximum ice level at only a portion of the ice bin. 
   
   
       14 . The clear ice maker unit of  claim 13 , wherein the prescribed time period is set according to a time needed to complete a prescribed number of ice making cycles. 
   
   
       15 . The clear ice maker unit of  claim 14 , wherein the first temperature is essentially 33 degrees Fahrenheit, the second temperature is essentially 34 degrees Fahrenheit and the prescribed time period is essentially one hour. 
   
   
       16 . The clear ice maker unit of  claim 10 , further comprising a user input connected to the controller, wherein the first temperature can be set by the user input. 
   
   
       17 . The clear ice maker unit of  claim 10 , wherein the sensor is a thermistor. 
   
   
       18 . The clear ice maker unit of  claim 10 , wherein the ice storage bin is not refrigerated. 
   
   
       19 . A method for making clear ice in a clear ice maker unit having a clear ice maker mechanism disposed in an ice maker chamber of an insulated cabinet, the clear ice maker mechanism being capable of cascading water over a vertically disposed evaporator during a plurality of ice making cycles and depositing clear ice formed on the evaporator into an ice bin within the cabinet, the method comprising:
 detecting an uneven ice distribution in the ice bin in which ice is disposed in the ice bin at or above a maximum ice level at only a portion of the ice bin; and   prohibiting a next ice making cycle following detection of an uneven ice distribution condition.   
   
   
       20 . The method of  claim 19 , further including:
 sensing an ice bin temperature at a maximum ice level in the ice bin before initiation of the next ice making cycle;   prohibiting initiation of the next ice making cycle if the bin temperature is less than or equal to a first temperature; and   prohibiting initiation of the next ice making cycle if the bin temperature is less than or equal to a second temperature for more than a prescribed period of time.