Rainfall chiller

Abstract

A counterflow chiller for cooling products on a conveyor employs a plurality of recirculating cooling modules in fluid communication with each other. Each recirculating cooling module sprays coolant over a portion of the conveyor to adjust the temperature of a product on the conveyor. An axial pump pumps coolant from a reservoir in a first recirculating coolant module to a sprayer, which sprays coolant over the product. Overflow coolant spills from one recirculating cooling module to another recirculating cooling module operating at a higher equilibrium temperature.

What is claimed is: 
     
         1 . A chilling system for chilling products, comprising:
 a conveyor for conveying a product; and   a plurality of recirculation modules, each recirculation module comprising a reservoir below the conveyor, a pump for pumping coolant from the reservoir, a pan for spraying pumped coolant over the product on the conveyor, and an outlet passageway in the reservoir for passing coolant into an adjacent reservoir or an outlet of the chilling system.   
     
     
         2 . The chilling system of  claim 1 , wherein the pan comprises an array of opening for creating a rainfall over the product. 
     
     
         3 . The chilling system of  claim 1 , wherein each recirculation module comprises a plurality of pans. 
     
     
         4 . The chilling system of  claim 1 , wherein the pump comprises an axial pump. 
     
     
         5 . The chilling system of  claim 4 , wherein the axial pump includes a removable flanged shroud. 
     
     
         6 . The chilling system of  claim 4 , wherein the axial pump includes an automatically engageable flow deflector. 
     
     
         7 . The chilling system of  claim 1 , wherein an inlet of the conveyor is at a first end of the chilling system and an inlet for coolant is at a second, opposite end of the chilling system. 
     
     
         8 . A recirculating module for a chiller, comprising:
 a reservoir having an inlet opening and a spillover opening;   an inlet for a conveyor above the spillover opening;   an outlet for the conveyor above the spillover opening;   a pump having a pump inlet in communication with the reservoir, and a pump outlet; and   a sprayer in communication with the pump outlet for spraying pumped coolant over items on the conveyor.   
     
     
         9 . The recirculating module of  claim 8 , wherein the pump is an axial pump. 
     
     
         10 . The recirculating module of  claim 9 , wherein the axial pump comprises a removable shroud. 
     
     
         11 . The chilling system of  claim 9 , wherein the axial pump includes an automatically engageable flow deflector. 
     
     
         12 . The recirculating module of  claim 8 , wherein the sprayer comprises a pan having an array of openings extending across the width of the conveyor. 
     
     
         13 . The recirculating module of  claim 8 , wherein the sprayer comprises a series of pans having arrays of openings. 
     
     
         14 . The recirculating module of  claim 13 , further comprising a flow distribution pan for dividing pumped coolant from the pump outlet into the series of pans. 
     
     
         15 . The recirculating module of  claim 8 , further comprising a conveyor belt extending through the inlet and the outlet for carrying product through the module. 
     
     
         16 . A method of changing the temperature of a product on a conveyor comprising:
 conveying a product through a chiller;   spraying coolant over the product in a first zone using a first sprayer;   collecting sprayed coolant in the first zone;   pumping sprayed coolant in the first zone back to the first sprayer;   passing overflow coolant from the first zone into a second zone; and   spraying coolant over the product in the second zone using a second sprayer.   
     
     
         17 . The method of  claim 16 , further comprising the step of collecting sprayed coolant in the second zone. 
     
     
         18 . The method of  claim 17 , further comprising the step of pumping sprayed coolant in the second zone back to the second sprayer. 
     
     
         19 . The method of  claim 18 , further comprising the step of passing overflow coolant from the second zone into a third zone. 
     
     
         20 . The method of  claim 16 , wherein the first zone has a lower equilibrium temperature than the second zone.