Multiple barrel frozen product dispenser

Abstract

A frozen product dispenser is characterized by at least two product freeze barrels for receiving product therein and for freezing the product for dispensing, and a refrigeration system for chilling the at least two barrels. The refrigeration system has at least two evaporators for and heat transfer coupled to each barrel, separate and controllable expansion valves each having an outlet coupled to an inlet to an inlet to an associated one of the evaporators, at least two compressors having outlets coupled to inlets to the expansion valves and inlets coupled to outlets from the evaporators, and at least one condenser in fluid circuit between outlets from the compressors and inlets to the expansion valves. The refrigeration system is controllable to selectively operate one or more of the compressors and one or more of the expansion valves in accordance with the cooling requirements of the barrels to provide an improved turndown ratio for improvements in efficiency of operation of the refrigeration system in response to changing cooling load requirements of the product barrels.

1 . A frozen product dispenser, comprising: 
 at least two product freeze barrels for receiving and chilling product for dispensing; and    a refrigeration system for chilling said at least two barrels, said refrigeration system including a plurality of evaporators heat transfer coupled to associated ones of said at least two barrels with at least two evaporators per barrel for chilling said barrels, a plurality of controllable expansion valves each having an outlet coupled to an inlet to an associated one of said evaporators, at least two compressors having inlets coupled to outlets from said evaporators, and at least one condenser coupled between outlets from said at least two compressors and inlets to said expansion valves.    
   
   
       2 . A frozen product dispenser as in  claim 1 , including a control system for sensing the chilling requirements of each of said at least two barrels and for controlling operation of said at least two compressors and said plurality of expansion valves to selectively operating one or more of said at least two compressors and one or more of said plurality of expansion valves to chill each of a selected one or more of said at least two barrels at rate in accordance with the sensed chilling requirements thereof.  
   
   
       3 . A frozen product dispenser as in  claim 1 , wherein said at least two barrels are two barrels, said at least two evaporators per barrel are two evaporators per barrel, said at least two compressors are two compressors, and said at least one condenser is one condenser, and including a control system sensing the chilling requirements of each of said two barrels and for controlling operation of said two compressors and said expansion valves to selectively operate one or both of said compressors and one or more of said expansion valves to chill each of a selected one or both of said two barrels at a rate in accordance with the sensed chilling requirements thereof.  
   
   
       4 . A frozen product dispenser as in  claim 1 , wherein said inlets to each of said compressors are coupled to said outlets from each of said evaporators, and said at least one condenser is coupled between said outlets from each of said at least two compressors and said inlets to each of said evaporators.  
   
   
       5 . A frozen product dispenser as in  claim 1 , including a control system for operating said refrigeration system, said control system including means for sensing the state to which product in each of said at least two barrels is chilled, and means responsive to said sensing means to operate one or more of said compressors and one or more of said expansion valves to chill one or more of said evaporators to thereby chill each of one or more of said barrels at a rate selected in accordance with the sensed state to which product is chilled therein.  
   
   
       6 . A refrigeration system for chilling product in at least two containers, said refrigeration system including a plurality of evaporators heat transfer coupled to associated ones of said containers with at least two evaporators per container for chilling product in said containers, a plurality of controllable expansion valves for said evaporators, each expansion valve coupled at an outlet therefrom to an inlet to an associated one of said evaporators, at least two compressors coupled at inlets thereto to outlets from said evaporators, and at least one condenser coupled between outlets from said compressors and inlets to said expansion valves.  
   
   
       7 . A refrigeration system as in  claim 6 , including a control system for operating said refrigeration system, said control system including means for sensing the state to which product in each of said containers is chilled, and means responsive to said sensing means to operate one or more of said compressors and one or more of said expansion valves to deliver refrigerant to one or more of said evaporators to chill each of one or more of said containers at a rate selected in accordance with the sensed state to which product is chilled therein.  
   
   
       8 . A method of operating a frozen product dispenser having at least two product freeze barrels for receiving and chilling product for dispensing, and a refrigeration system for chilling the at least two barrels, the refrigeration system including a plurality of evaporators heat transfer coupled to associated ones of the at least two barrels with at least two evaporators per barrel for chilling the barrels, a plurality of controllable expansion valves each having an outlet coupled to an inlet to an associated one of the evaporators, at least two compressors having inlets coupled to outlets from the evaporators, and at least one condenser coupled between outlets from the at least two compressors and inlets to the expansion valves, said method comprising the steps of: 
 sensing the state to which product in each barrel is chilled; and    in response said sensing step, operating one or more of the compressors and one or more of the expansion valves to chill one or more of the evaporators to thereby chill one or more of the barrels at a rate selected in accordance with the sensed state to which product is chilled therein.    
   
   
       9 . A method of making a chilled product, comprising the steps of: 
 introducing product into at least two containers; and    chilling the at least two containers to chill the product therein,    said chilling step comprises the steps of:    heat transfer coupling a plurality of evaporators to the containers with at least two evaporators per container;    coupling each of a plurality of controllable expansion valves to an inlet to an associated one of the evaporators; and    delivering refrigerant from one or more of at least two compressors through at least one condenser and a selected one or more of the expansion valves to the associated evaporators to chill one or more of the containers.    
   
   
       10 . A method according to  claim 9 , including the step of sensing the state to which product in each container is chilled, and controlling said delivering step in accordance with said sensing step to chill only those containers in which product is chilled to less than a selected state.