Ice-machine evaporator and control system

Abstract

An apparatus and method for forming ice inside a helical refrigerated tube and harvesting the ice by warming the tube is provided. The device uses water pressure to push the ice out of the evaporator. At least a portion of the body of the evaporator is formed by extrusion. The evaporator can be made from aluminum.

1 . An evaporator for an ice-making machine comprising:
 a body made at least in part by an extrusion process, wherein said body has a refrigerant channel and a water channel with an inner surface, said refrigerant channel being adapted for flow of refrigerant therethrough, said inner surface being adapted for formation of ice thereon, and wherein said refrigerant channel is in thermal communication with said water channel.   
   
   
       2 . The evaporator of  claim 1 , wherein said body has a helical shape. 
   
   
       3 . The evaporator of  claim 1 , wherein said refrigerant channel is a plurality of refrigerant channels. 
   
   
       4 . The evaporator of  claim 1 , wherein at least two of said plurality of refrigerant channels are diametrically opposed along an outer surface of said water channel. 
   
   
       5 . The evaporator of  claim 1 , wherein said body is made from aluminum. 
   
   
       6 . An ice-making machine comprising:
 an evaporator; and   a control system comprising a single switch that senses water level in a reservoir located at an outlet of the evaporator.   
   
   
       7 . The machine of  claim 6 , wherein the reservoir has holes therethrough for drainage. 
   
   
       8 . The machine of  claim 6 , wherein during a freezing cycle, water flows into the reservoir at a rate that exceeds a drainage rate of the reservoir. 
   
   
       9 . The machine of  claim 8 , wherein when a water level of the reservoir reaches a predetermined minimum, the single switch opens a hot gas valve in the circuit to commence a harvest cycle and eject ice at least in part based on a pressure of the water being pumped into the evaporator.