Ice machine with assisted harvest

#The present invention relates to an ice making machine, and more particularly to a cube ice making machine utilizing a defrost harvest cycle with assisted ice release.

#There are several major types of automatic ice making machines. Predominant forms of ice produced in such machines are cubes and flakes. Cubes are preferred for cooling carbonated beverages served in cups because cube ice generally causes less foaming of the beverage.

#Cube ice making machines themselves come in a number of varieties. Some form individual ice cubes, while others, referred to as slab-type machines, have a grid of ice forming pockets that freeze individual cubes. When the cubes are to be harvested, the ice starts to melt. Just as water expands as it freezes into ice, the ice and water contract as the ice starts to melt. This creates a vacuum in the pockets. In addition, as the ice tries to slide out of the pockets, the surface tension of the water holds the water between the ice cube and the grid side walls. This adds to the vacuum, which must be broken before the cubes will slide out of the pockets. Preferably, ice is allowed to freeze over the edges of the grid to bridge between individual cubes. When it is time to harvest the cubes, the ice bridge holds the cubes together and makes the cubes all come out in one slab once the vacuum is overcome, thus helping to achieve a complete harvest.

#FIG. 1 is a perspective view of the ice making compartment in a preferred ice making machine of the present invention; with several sections of the dividers making up the ice-forming mold removed from the evaporator assembly for sake of clarity.

#FIG. 2 is a schematic drawing of the refrigeration system of the ice making machine of FIG. 1.

#FIG. 3 is a schematic diagram of the water system of the ice making machine of FIG. 1.

#A preferred ice making machine of the present invention is very similar to a model QY-1004A ice machine sold by Manitowoc Ice, Inc., Manitowoc, Wis. Many parts of the machine are the same as those shown in U.S. Pat. No. 5,586,439, incorporated herein by reference, and are therefore not shown or discussed in detail. The term “ice cube” used herein has its general meaning in the ice machine business. Ice cubes can be of many sizes and shapes, although rectangular shapes are preferred in the present invention.

#The preferred ice making machine of the present invention has three major systems: a refrigeration system, a water system and a harvest assist system. Components and systems of the preferred ice making machine of the present invention are shown in FIGS. 1-8. FIG. 2 is a schematic diagram of the refrigeration system. FIG. 3 is a schematic diagram of the water system. FIG. 8 is a schematic diagram of the harvest assist system. Some of the components of these systems, as well as other components of the ice making machine, are shown in FIGS. 1 and 4-7. FIGS. 9, 12 and 13 disclose alternate harvest assist systems. FIGS. 10 and 11 disclose a preferred air hose connector and nozzle assembly.

#As shown in FIG. 3, the preferred water system, which is conventional for Manitowoc-brand cube ice machines, includes a water supply or inlet 1. A water level probe 2 is used to control the depth of water in a sump 3. A circulating pump 4 draws water out of the sump and pumps it up to a distributor tube 7. Water falls from the distributor tube 7 over the ice-forming mold, sometimes also known as an evaporator plate 6. A water curtain 5 keeps water from splashing out of the front of the water compartment and directs water that does not freeze back into the sump 3. An ice thickness sensor or probe 8 is used to monitor the build-up of the ice bridge on the front of the ice-forming mold 6. When the machines goes into a harvest mode, a solenoid valve 9 is opened to allow water from the sump to enter a drain line 10. Alternatively, the drain line 10 and solenoid 9 can be located after the pump, so that the water in the sump is pumped out to the drain. FIG. 1 shows several of these components, although the water curtain 5 is removed and other components such as the water line interconnecting the pump 4 and the distributor 7 are not shown in the perspective view of the water compartment shown in FIG. 1. FIG. 1 also shows the location of the electrical controls housed in compartment 81.