US2648956A - Ice maker - Google Patents

Description

Aug. 18, 1953 J. FLETCHER EI'AL ICE MAKER Filed Jan. 19, 1950 Patented Aug. 18, 1953 UNITED STATES ATENT OFFICE ICE MAKER Delaware Application January 19, 1950, Serial No. 139,366

5 Claims.

This invention relates to an ice maker for use in restaurants, bars, or the like and, more partioularly, to an ice maker adapted to be provided with city water for the formation of ice including means for preventing substantial concentration of minerals in the water used for ice formation without substantial loss in refrigeration capacity of the device.

In ice makers of the type contemplated herein, to permit full use of existing refrigeration capacity, water to be formed into ice is supplied from a tank to the ice forming members and again returned to the tank. It will be appreciated the water returned to the tank is cooled by the ice forming members so that when such water is again supplied to the ice forming members it is substantially at freezing temperature. Hence, the refrigeration effect required to form such water into ice is not great thereby permitting a small refrigeration system to be employed which may be operated economically.

Unfortunately, in many areas, the amounts of minerals present in the water supplied for use in the formation of ice are great. Continual reuse of such water, as required for economical It has been proposed to eliminate mineral de-' posits by continuously bleeding water from the supply tank while continuously supplying fresh water to the tank; such practice, of course, prevents undue concentration of minerals in the water being used, since the water in the tank is diluted, thus preventing too high a concentration of minerals therein. Such practice is highly unsatisfactory in actual operation for it greatly reduces the refrigeration capacity of the device. It reduces the refrigeration capacity of the device since the fresh water supplied to the tank may be at a temperature of approximately 60 F. for example; thus water in the tank is at an approximate temperature of 60 F. so that when it is supplied to the ice forming equipment it is necessary to reduce the temperature of such water to 32 F. to permit the formation of ice. Since it is necessary for economical operation that water supplied to the ice form ng m r be at a temperature as close to freezing temperature aspossible, it will be appreciated this proposal is not satisfactory since it reduces capacity of the equipment, perhaps as much as 25% or even greater depending upon the amounts of minerals in the water and the consequent dilution required.

The chief object of the present invention is to provide an ice maker equipped with means for preventing substantial concentration of minerals in water used for ice formation, without substantial loss of refrigeration capacity. Likewise, in vicinities in which a substantial amount of corrosive elements such as acids are present in the water employed for ice making purposes which may not freeze into ice, the present invention is of value since it prevents substantial concentration of such elements in the water used for ice manufacture by dilution thereof.

An object of the present invention is to provide an ice maker equipped with economical means for preventing formation of mineral deposits in the tank without substantial loss of refrigeration capacity.

A further object is to provide an ice maker in which fresh water is supplied to the machine without substantial loss of refrigeration effect. Other objects of our invention will be readily perceived from the following description.

This invention relates to an ice maker including an ice forming member, means for refrigerating the ice forming member, means for heating the ice forming member to harvest formed ice, a water tank, means to circulate water from the tank to said member, cooled water unused in the formation of ice returning to the tank, and means for preventing substantial concentration of minerals in the water without substantial loss of refrigeration capacity, said means including an element for supplying fresh Water to the tank, means for bleeding water from the tank, and means for placing the stream of fresh water being supplied to the'tank in heat exchange relation with the stream of water being removed from the tank.

The attached drawing is a diagrammatic view of an ice maker embodying the present invention.

Referring to the drawing, there is shown an ice maker including a plurality of tubes 2 in which ice is formed. An evaporator 3 of a refrigeration system is disposed about the exterior wall of the tubes in order to cool spaced portions of the tubes to form separate pieces of ice. Evaporator 3 isa portion of a refrigeration system which includes a compressor 4 connected by a line 5 to a condenser 6, condenser 6 being connected to evaporator 3 by line 1 in which an expansion means 8 such as a capillary tube or expansion valve is placed to regulate flow of refrigerant to evaporator 3. A line 9 connects evaporator 3 with compressor .4; preferably, an accumulator I i) is placed in line 9 to-prevent liquid refrigerant passing to the compressor 4. Condenser 6 may be water-cooled by the supply of city water through line H in heat exchange relation with refrigerant therein although, if desired, pendenser may be air-cooled.

To harvest ice formed in tubes g, ;a line I g rnay be provided connecting line 5 with line i to permit hot gas from the compressor to be circulated through evaporator 3. A solenoid valve l3 may be provided in line l2 and actuated auto.- matically in response to an indication that the formation of ice in tubes 2 is complete to harvest formed ice, When the harvesting operation is complete, valve l3 may be again actuated to resume operation of the refrigerating system in the usual manner.

A water supply tank 38, preferably, is below tubes '2 or is connected to such tubes in any suitable manner in order that water passing through the tubes is returned to tank I8. As shown pump P withdraws water from tank l8 and supplies sufiicient water through line 2 to supply members 2! placed above tubes 2; preferably targets 22 are placed within tubes 2 in order that the sprays of water are directed to the interior wall of each tube, A screen or grating 23 is placed beneath tubes 2 to permit formed ice to be directed to a bunker (not shown) while permitting water passing through the tube to be returned to tank [8.

In the present invention, fresh water is supplied to tank it while water is continuously drained from tank It to prevent concentration of minerals in the water the tank. fresh water supplied to tank 58 be at a temperature of approximately 60 as is customary when city water is employed in the formation of ice. The water leaving 8 to waste may be at a temperature of about 33 F. since it been cooled greatly by passing through tubes 2. As shown, the fresh water line 2,4 is connected to condenser water line H. Line 26 is connected to a heat exchanger, 25 hereinafterdescribed while line 25 connects heat exchanger .25 with tank is. Th bleed line 2] is connected to an inlet-8 adjacent one end of heat exchanger 25, and outlet 29 is provided in heat exchange-r25 to permit the Water containing ninerals to flow through line 38 to a suitable drain. To permit the water bleeding from the tank to be vented, abypass line 36 is provided.

Heat exchanger 25 contains a coil -31 connected to lines 25 and 25 to permit fresh water flowing to tank ill to pass therethrough. To permit Water to be easily removed from ;'heat exchanger 25 when it is desired to clean the exchanger, a drain 32 may be provided therein.

Considering the operation of the devicatherefrigeration equipment cools the walls of tubes 2 while simultaneously pump P circulates water from tank 28 through tubes 2. Water draining from tubes 2 returns to tank 18. Within a short periodof time it will be appreciatedthetemperature of the water in tank 18 is at approximately freezing temperature. When a satisfactory quantity of ice is formed in tubes 2, solenoid valve 53 may be actuated to supply hot gas to evaporator 3 thereby thawing the-ice from-the in- 4 terior wall of the tubes. The formed ice drops from the tubes onto grating 23 and is forwarded by forces of gravity to a suitable bunker.

While the refrigerating and harvesting steps are being conducted, fresh water is supplied through line 2 5 to heat exchanger 25 and from heat exchanger 25 through line 26 to tank i8. At the same time, water from tank E8 is continuously removed through line 2? to heat exchanger 25 in heat exchange relation with the fresh water passing through coil 3! and then flows to a drain. Fresh water entering heat exchanger 25 may be at a temperature of about 60. Water flowing from tank is is at a temperature of about 33 F. The fresh water passes through line 25 to tank 18 and is lowered in temperature to about 48 F. while the water from tank it going to waste is raisedin temperature to about 57 F. It will be understood the temperature of the fresh water so obtained depends upon the percentage of waste water compared to the percentage of water frozen; with waste water approximately equal to the amount of water in the formed ice the temperature is about 48 F. By this means the refrigeration effect is saved, permitting smaller refrigeration equipment to be employed and reducing the cost of operation while preventing formation of mineral deposits in the tank.

The present invention provides an ice maker including means for preventing concentration of minerals in the water used for ice formation without substantial loss of refrigeration capacity. The means so provided do not materially increase the cost of operation of the device and do not materially affect initial cost.

While we have described a preferred embodiment of our invention it will be understood our invention is not limited thereto since it may be otherwise embodied within the scope of the following claims.

We claim:

1. In an ice maker, the combination of a pluirality of tubes in which ice is formed, means for refrigerating the tubes including a water-cooled condenser, means for heating the tubes to harvest formed ice, a water tank, means to circulate water from the tank through the tubes while the tubes are being refrigerated, cooled water unused in the formation of ice returning to the tubes, and means for preventing substantial concentration of minerals in the cooled water Without substantial loss of refrigeration capacity, said means including a control for maintaining a desired level of water in the tank, a line through which cooling water is supplied to the condenser, a line connected to the condenser water line for continuously supplying fresh water to the tank, a third line connected to a drain for bleedin Water from the tank, a shell member in the third line containing an inlet adjacent one end and an to prevent concentration of minerals in the supply water without reducing the refrigeration capacity of the ice maker, the steps which consist in forming ice while cooling water from which the ice is formed, returning the cooled water to a water -reservoir, supplying a stream of water from the reservoir for ice formation, bleeding a second separate stream of water from the reservoir to prevent concentration of minerals in the water supplied for ice formation, supplying a stream of fresh water to the reservoir, passing the second stream and the stream of fresh water in heat exchange relation to prevent substantial loss of refrigeration capacity by the removal of cooled Water from the reservoir, harvesting the formed ice while discontinuing ice formation, then discontinuing the harvesting operation, and repeating the steps automatically until a desired amount of ice is formed.

3. In a method of operation of an ice maker the steps which consist in refrigerating an ice making element, supplying an excess of water from a reservoir to the element for the formation of ice thereby cooling water unused in ice formation, returning the cooled water to the reservoir, again supplying an excess of water from the reservoir to the ice making element, bleeding water from the reservoir to prevent concentration of minerals in the water supplied for ice formation, replenishing the reservoir with fresh water, passing the streams of fresh water and waste water in heat exchange relation to prevent substantial loss of refrigeration capacity by the removal of cooled water from the reservoir, discontinuing supply of water to the ice making element and refrigeration of the ice making element, heating the ice making element to harvest formed ice, then after harvesting discontinuing heating of the ice forming element and again supplying water to the ice making element and refrigerating the same.

4. In an ice maker, the combination of an ice forming element, means for refrigerating the element including a water cooled condenser, means for harvesting formed ice, a water tank, means for circulating water from the tank to the ice forming element while the element is being refrigerated, cooled water unused in the formation f ice returning to the tank, and means for preventing substantial concentration of minerals in the cooled Water without substantial loss of refrigeration capacity, said means including a control for maintaining a desired level of water in the tank, a line connected to the tank for supplying a stream of fresh water directly thereto, flow of fresh water through said line being regulated by said control, a second line connected to a drain in said tank for bleeding a stream of Water from the tank, and means in said lines for placing said streams in heat exchange relation.

5. An ice maker according to claim l in which said heat exchange means comprise a shell, a coil in said shell, and inlets and outlets to said shell and coil for the fresh water and the waste water arranged to pass the stream of fresh Water in counterflow heat exchange relation with the stream of water removed from the tank.

JAMES L. FLETCHER. SAMUEL C. OSBORNE.

References Cited in the file of this patent UNITED STATES PATENTS Number

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