Title:
TUBE ICE GENERATOR
United States Patent 3759061


Abstract:
Ice generator in which water is frozen in tubes extending vertically within a surrounding casing defining a freezing chamber spaced above the bottom of which is a distributor plate having apertures surrounding the tubes and defining a separate chamber into which a warm gas is passed to heat the tubes to cause the ice rods to slide therefrom.



Inventors:
Nilsson, Nils Edvin Folke (Norrkoping, SW)
Eurenius, Jimmie Arne (Norrkoping, SW)
Application Number:
05/178029
Publication Date:
09/18/1973
Filing Date:
09/07/1971
Assignee:
STAL Refrigeration AB (Norrkoping, SW)
Primary Class:
Other Classes:
62/348
International Classes:
F25C1/06; F25C5/14; (IPC1-7): F25C5/10
Field of Search:
62/72,352,348 165
View Patent Images:
US Patent References:
2721452Ice making machine1955-10-25Brandin et al.
1518162Cooling room for hospitals1924-12-09Parkinson
0827479N/A1906-07-31



Primary Examiner:
Wayner, William E.
Assistant Examiner:
Tapolcai Jr., William E.
Claims:
We claim

1. Tube ice generator for the production of ice by freezing water, said generator comprising a cylindrical, vertically arranged casing having tube plates at the top and bottom and vertical tubes therebetween, means for passing water through said tubes, means for supplying low liquid pressure refrigerant to a main chamber between said casing and said tubes, said low pressure refrigerant being vaporized while absorbing heat from the water flowing down through the tubes, means for supplying gaseous warm high pressure refrigerant to said chamber, a distributor plate located above the bottom plate of the main chamber, said distributor plate having holes for the tubes, said holes having a diameter which is greater than the outer diameter of the tubes so that annular gaps are formed around the tubes, said distributor plate forming a second chamber between the bottom plate and the distributor plate, and means for supplying warm high pressure refrigerant to said second chamber, said warm high pressure refrigerant escaping into the main chamber through said distributor plate.

2. Tube ice generator according to claim 1, the areas of the gaps around the central tubes being greater than the areas of the gaps around the outer tubes.

3. In a refrigeration system including a low pressure side and a high pressure side, an ice generator comprising:

Description:
BACKGROUND OF THE INVENTION

The present invention relates to a tube ice generator for the production of ice by freezing water which flows downwardly along the inner walls of substantially vertical tubes which are attached between two tube plates and surrounded by a chamber inside a casing in which chamber a liquid refrigerant is vaporized while absorbing heat from the water flowing down the tubes, after which the ice thus formed is loosened from the tube walls by supplying warm coolant in gaseous form.

For the purpose of increasing the capacity of the generator and for improving the quality of the ice it is important to reduce the time required to loosen the ice rods to a minimum.

This time element is largely dependent on the even distribution of the high pressure gas in the chamber or spaces between the tubes and the casing and provisions should be made to assure a concentrated supply of heat to the lower ends of the tubes. This is primarily due to the fact that the lower tube plate 3 must be heated to the melting point of the ice before the part of the ice rod at the outlet of the tube will loosen. Concentration of heat at the lower ends of the tubes can be effected in several known ways. For example, the generator can be provided with double tube plates at the bottom and in the space between these plates high pressure gas may be allowed to condense continuously. The ends of the tubes are thus kept warm and the formation of ice is prevented. This arrangement has the drawback that the cooling effect is reduced due to the supply of heat. Further, the welding of the double plates is difficult. These problems have been solved by the present invention, which is characterised by the subsequent claim.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is illustrated in the accompanying drawings where

FIG. 1 shows a tube ice generator in longitudinal section and

FIG. 2 shows a part of the same drawn to a slightly larger scale.

1 DESIGNATES VERTICAL TUBES WHICH ARE ATTACHED BETWEEN TWO TUBE PLATES 2, 3 AND SURROUNDED BY A CHAMBER 4 WITHIN A CASING 5.

Water is supplied at the upper ends of the tubes 1 from a conduit 6. The water flows through the interior of the tubes and freezes to ice due to vaporization of the refrigerant in the chamber 4. The water which does not freeze is collected in a container 7 and pumped by a pump 8 through the tube 6 back to the inlet of tubes 1.

9 AND 10 DESIGNATE CONDUITS FOR THE REFRIGERANT MEDIUM TO AND FROM THE CHAMBER 4.

When the ice tube has formed to the desired thickness, the pump 8 is stopped. During the freezing cycle the valves 11, 12 in the conduits 9, 10 to the low pressure side are open and the valves 13, 14 in conduits 15, 16, which connect the tube ice generator to the high pressure side of the coolant compressor, are closed.

When the pump 8 has been stopped the valve 12 is closed and the valve 14 opened. Liquid refrigerant from the chamber 4 is thus pressed through the valve 11 to a liquid separator, not shown. When all the liquid has been evaporated or purged from the chamber 4, valves 11 and 14 are closed, valve 13 opened and an ice knife 17 carried by the shaft 20 brought to rotate by the motor 21.

Secured to the end of the shaft below the knife 17 is a centrifugal basket 22 for receiving the cut ice pieces and from which they may be ejected through the outlet chute 23.

According to the invention, a distributor plate 18 is provided which has holes for accommodating the tubes and which is attached to the casing 5 and arranged above the lower tube plate 3 which is arranged at the bottom ends of the tubes 1 and defines a second or bottom chamber 4b. These holes have a diameter greater than the outer diameter of the tubes 1 so that annular gaps 19 are provided around the tubes, the areas of the gaps around the centrally located tubes being greater than the area of the gaps around the outer tubes.

The high pressure gas which is led in through the valve 13 enters a space between the tube plate 3, and distributor plate 18 and then through the gaps 19 along the outside surfaces of the tubes 1. The ice rods are thus thawed loose and drop down to be cut and removed.

The high pressure drops at the gaps produce an even distribution of the gas to each gap and in this way a concentrated and uniform heat supply is obtained, resulting in a uniform heating of each tube end. In ice generators having many tubes the flow resistance of the gas between the tubes may influence the distribution around the tubes. This can be compensated by making the gaps around the central tubes larger than the gaps around the surrounding tubes.