Ice-making machine with control system

Abstract

An ice-making machine that includes an evaporator and a simple control system, with a single switch, that initiates a harvest cycle by determining a flow rate of water out of the evaporator. The evaporator is a coiled in a flat, space-saving spiral.

1 . An ice-making machine comprising:
 an evaporator, having a spiral wound shape; and   a control system comprising a sensor to sense a water level in a reservoir, wherein said reservoir is disposed to receive passes through said evaporator.   
   
   
       2 . The machine of  claim 1 , wherein said reservoir comprises holes therethrough for drainage. 
   
   
       3 . The machine of  claim 1 , wherein during a freezing cycle, water flows into said reservoir at a rate that exceeds a drainage rate of the reservoir. 
   
   
       4 . The machine of  claim 3 , wherein when said water level of said reservoir reaches a predetermined minimum, said sensor initiates a harvest cycle of ice disposed within said evaporator. 
   
   
       5 . The machine of  claim 1 , further comprising a sump in fluid communication with said reservoir, such that water flows from said reservoir to said sump, and wherein at least a portion of said water in said sump is recirculated to evaporator. 
   
   
       6 . A method of harvesting ice from an ice-making machine, wherein said ice-making machine comprises an evaporator and a reservoir, the method comprising the steps of:
 detecting the level of water in said reservoir;   directing a flow of hot gas through said evaporator when said level of water in said first reservoir is equal to or less than a predetermined value; and   terminating said flow of hot gas to said evaporator when said level of water in said reservoir is equal to or greater than a second predetermined value.   
   
   
       7 . The method of  claim 6 , wherein said detecting step comprises a sensor, said sensor comprising a tube disposed within said reservoir, wherein said tube is in communication with an air pressure sensing switch. 
   
   
       8 . The method of  claim 7 , wherein said directing step is performed by opening a refrigerant valve in response to said switch.