Method and apparatus for making nugget ice in a refrigerator

Abstract

An ice making system for producing on-demand nugget ice in a refrigerator includes an auger type icemaker having a double thin-walled cylindrical flooded, evaporator and a chilled water reservoir connecting to refrigerated rater. When ice is demanded, the evaporator is then connected to the refrigeration circuit through a dedicated refrigerant control device to achieve −40° F. rapid cooling. With near 32° F. chilled water, a layer of ice can form on the evaporator surface within 1 minute. Meanwhile a rotating auger scrapes ice layer into flake ice and compresses it through an extrusion and delivery tubing to form cylindrical ice. Then it breaks into nugget ice in the tubing and drops in an ice container.

1 . An ice making system that can produce nugget ice in a refrigerator comprising:
 an auger type icemaker;   whereby said auger type icemaker is used to produce nugget ice in the refrigerator.   
     
     
         2 . An ice making system of  1 , which can produce on-demand nugget ice within one minute in a refrigerator comprising:
 an auger type icemaker including a liquid flooded cylindrical evaporator and a rotating auger;   a gear motor connected to said rotating auger;   a water reservoir with a float valve connected to refrigerated water and said liquid flooded cylindrical evaporator;   an ice container located above said water reservoir;   a dedicated refrigerant control device having a separate capillary tube and a 3-way solenoid valve connected to said liquid flooded cylindrical evaporator;   whereby said liquid flooded cylindrical evaporator is connected to the refrigeration circuit through said dedicated refrigerant control device having a separate capillary tube to achieve quick cooling. With refrigerated water, a layer of ice can form on the inside surface of the inner cylinder of said liquid flooded cylindrical evaporator within 1 minute. Meanwhile said rotating auger scrapes the ice layers into flake ice and compresses the flake ice through an extrusion and delivery tubing to form cylindrical ice. Then the cylindrical ice breaks into nugget ice in said extrusion and delivery tubing and drops in said ice container.   
     
     
         3 . An ice making system of  claim 2 , wherein said liquid flooded cylindrical evaporator has stainless steel double thin-walled cylinders including an outer cylinder and an inner cylinder. The space between the two cylinders is sealed and filled with −40° F. liquid refrigerant. Said liquid flood cylindrical evaporator is constructed with an inlet at the bottom and an outlet at the top that only liquid will be kept but vapor will be allowed to escape. 
     
     
         4 . An ice making system of  claim 3 , wherein a piece of stainless steel tubing is welded on the inner cylinder of said liquid flooded cylindrical evaporator. One end of said piece of stainless steel tubing that is located inside the inner cylinder is shaped as a cutter that is used to break the compressed cylindrical ice. 
     
     
         5 . An ice making system of  claim 2 , wherein said water reservoir located above said liquid flooded cylindrical evaporator is connected to refrigerated water in the refrigerator. Said float valve prevents said water reservoir from overfilling and maintains the inner cylinder full of refrigerated water. 
     
     
         6 . An ice making system of  claim 2 , wherein water from melted ice returns to said water reservoir to avoid water dripping in the refrigerator. 
     
     
         7 . An ice making system of  claim 2 , wherein said dedicated refrigerant control device having a separate capillary tube connects said liquid flooded cylindrical evaporator to the refrigeration circuit controlled by said 3-way solenoid valve. Said dedicated refrigerant control device having a separate capillary tube is optimized for operating at −40° F. evaporating temperature to produce −40° F. liquid refrigerant.