US2560488A - Combination soda fountain and ice-cream cabinet - Google Patents

Description

A. K. SMITH July 10, 1951 COMBINATION SODA FOUNTAIN AND ICE CREAM CABINET Filed Sept. 17, .1949

5 Sheets-Sheet l INVENTOR.

July w, 1951 A. K. SMITH 2,560,488

COMBINATION SODA FOUNTAIN AND ICE CREAM CABINET Filed Sept. 17, 1949 3 Sheets-Sheet 2 Emi 8W2.

,zmwlawli A. K. SMITH July 10, 1951 COMBINATION SODA FOUNTAIN AND ICE CREAM CABINET Filed Sept. 1'7, 1949 5 Sheets-Sheet 5 lllln MLTWZWV' Patented July 10, 1951 COMBINATION some FOUNTAIN AND ICE-CREAM CABINET Arthur K. Smith, Gloucester, Mass. Application September 17, 1949, Serial No. 116,267

g 4 Claims.

This invention relates eration cabinets for maintaining different temperatures in separate spaces within the same cabinet. In one aspect this invention relates to a combination cabinet'for simultaneously cooling carbonated water to near freezing temperature and refrigerating other articles requiring temperatures substantially below the freezing point of water.

'In general, combination soda fountain and ice cream cabinets are not available to small estab- "li'shments, such as country stores, delicatessens and the like. This is because the hitherto known ns for such combination cabinets include complicated machinery and auxiliaries rendering them too expensive and to bulky for convenient use on a small scale. The necessity for such costly and inconvenient design stems from the fact that in combination cabinets of thissort,

to refrigeration cabinets and more particularly to improvements in refrigtwo or more different refrigeration compartments must be kept at different temperatures. The ice cream should be kept in the vicinity of 0 F. and the soda water should be kept near 32 F. but, of course, it should not be allowed to freeze. Furthermore, the requirements as to cooling rate vary in the different compartments. Carbonators require rapid cooling mechanisms because, when they are in use, they introduce large quantities of comparatively warm water into the cooling compartment which water must be brought down to below 38 F. prior to leaving the cooling compartment for the best results in mixing cool drinks. Since the circulatory tract of the water cooling apparatus generally has a relatively small volume, the water passes through it rapidly and must be cooled accordingly. On the other hand, refrigerating ice cream, for storage purposes, "need not be extremely rapid. The introduction of heat due to opening the cabinet top for access to the ice cream is negligible in comparison to the heat introduced by the feed water for the carbonation system.

Generally, two separate refrigeration systems are used, one with a high instantaneous capacity to cool the feed water and carbonation system,

and the other with a low instantaneous capacity a to cool the ice cream. Various attempts have been made to use a single refrigeration system for this purpose. Thermostatically controlled to the compartments. This latter method generally provides successively warmer compartments and has the disadvantage of being unable to handle rapid cooling in one of the compartmentsat the end'of the series without a corresponding decrease in the temperature of the compartments in the first'part of the series, whether they need to be further cooled or not. Separate piping systems connected in parallel to the same refrigeration source have been constructed, employing thermostatically controlled valves at the entrance toeach system. Such apparatus has the disadvantage of requiring complicated piping systems and valves not feasible in the cheaper and more available refrigeration cabinets.

Lastly, conventional refrigeration systems are not satisfactory for maintaining temperatures close to but not below 32 F. In operation, the conventional systems usually have a span of from '10 to 15 degrees in temperature between the cut on point and the cut off point of the valves which control admission of the refrigerant. Furthermore, even after the refrigerant ceases to enter the coils, the temperature in the cabinet will continue to drop due to unavoidable lags'in the conduction and convection of heat within the cabinet surrounding the thermostatic control. Thus, in a conventional cabinet, the carbonated water must be kept at an average temperature of around 40 F. in order to avoid the risk of freezing the water, with the result that such conventional cabinets do not approach the optimum cooling desired.

It is an object of my invention to provide a method and apparatus for maintaining separate spaces in a refrigeration cabinet at different temperatures which method can be easily performed with one refrigeration system and without the "necessity for providing expensive, complicated or bulky apparatus.

It is another object of my invention to provide apparatus for maintaining separate spaces within a refrigeration cabinet at invention to provide a multi c0mpartment cabinet wherein the temperature in the compartments may be maintained in the vicinity of 0 F. and the temperature in a container within one .of the compartments may be maintained in the vicinity of but not below 32 F.

.In the accomplishment of these objects I pro- :vide a small carbonation unit immersed in .a

liquid, in a non-insulated, metal cooling tank. Passing through the cooling tank and likewise =immersed in the liquid is a large surface feed water conduit leading up to the carbonator. The

cooling tank is placed bodily within one of the {compartments of a conventional ice cream cab- -inet. It is a feature of my invention that the -'-coo1ing tank and the carbonator unit within it tion Of heat into a refrigerating cabinet for pur- I poses of regulating temperatures is opposed to universally held opinions on the subject of refrigeration, but yet constitutes one of the important contributions of this invention to the art.

It is a still further feature of my invention that the thermostatically controlled introduction of heat into cooling tank employs an extremely accurate thermocouple connected in series with ;an electric heating coil. Thus the introduction of heat into the tank may be controlled to within one degree of the critical 32 /2" F.

While it is an accepted proposition that heat transfer through a wall takes place at a uniform rate depending upon the temperature differential 0f the surrounding media, it is an extremely important feature of my invention that I am able to slow down the transfer of heat out of the cooling tank during periods of idleness. During periods of constant use, heat is extracted ,as fast as the walls of the tank are capable of conducting it, but the elements of my novel system are so arranged and controlled that during periods of idleness, a thin layer of ice builds up on the inside walls of the tank and effectually reduces the transfer of heat through the tank walls by eliminating the convection of the water adjacent to the surface of the tank walls on-the inside. When the apparatus again undergoes repeated use, the ice layer melts and rapid heat transfer through the walls of the tank again takes place. ducing the amount of heat introduced by the above mentioned heating coils while the carbonator is idle and means that the cooling tank may readily be left in the cabinet overnight without' causing the refrigeration system to work needlessly against the heating coil.

Further objects and features of my invention will best be understood and appreciated from the following description of a preferred embodiment thereof, selected for purposes of illustra-- tion, and described in the accompanying drawings in which:

Fig. 1 is a view in perspective of the combination cabinet of my invention,

Fig. 2 is a plan view of the combination cabinet,

Fig. 3 is a sectional view in side elevation of the combination cabinet of my invention along the line 3-3 of Fig. 2,

This feature is responsible for re- Fig. 4 is a plan View from above of the carbonator unit and feed water cooling tank with cover removed, and

Fig. 5 is an exposed view of the inside of the cooling tank in side elevatiomalong the line 5-5 of Fig. 4.

In the preferred embodiment of my invention, I employ a conventional refrigeration cabinet I0 4 members, but which present some resistance to the passage of heat.

In this illustrative example the compartments are indicated at I4, I6 and I8, respectively, with a space for the refrigeration mechanism indicated generally at 20. The refrigeration mechanism space 20 extends underneath the compartment I8 and therefore compartment I8 is not as deep as compartments I4 and I6. In order to save the compartments having larger volume for the storage of ice cream, I have herein selected compartment I8 for use in cooling the soda water of my combination cabinet but it will be understood that my invention is not dependent upon details of cabinet design nor the convenience of the compartment selected.

The soda fountain unit includes in its general organization a preserve and syrup rack 22, a soda faucet 24 mounted on the rack 22, preserve jars 26 and syrup dispensers 28 inserted in appropriate perforations in the rack, and a soda water cooling and carbonating unit indicated at 30. The cooling and carbonating unit 30 is inserted into compartment I8, resting on the bottom thereof, and the rack 22 is placed over the compartment opening. Of course, the cover for compartment I8 is discarded during the combined operations herein described. 7

It is desirable to maintain the syrup relatively cold preferably below 40 F. in order not to introduce unnecessary warmth into the drinks,' and it is further desirable to keep the preserves below 50 F. to deter flies from alighting thereon. Therefore it will'be seen that the rack 22 supports the jars 26'and dispensers 28 with their lower portions in position to be cooled by the cabinet Ill. The rack 22, however, extends beyond the margin of the compartment I8 on the side where the jars 26 are located with the result that they rest on the cabinet top adjacent to the entrance to compartment I8, while the deeper dispensers 28, extend part way down into compartment I8. Thus the dispensers 28 are main- .tained below 40 F. and the jars 26 are about At one end of the rack 22, the faucet 24 is permanently mounted and provided with a screened drain 32 appropriately located centrally in the rack below the faucet outlet.

The cooling and carbonating unit 30 will now be described and includes, in its general organization, an enclosed metal tank 34 completely filled with water or other suitable liquid, a feed water cooling coil 35, a carbonator unit indicated generally at 38, an electric heating coil 40, and a thermocouple 42.

The feed water cooling coil 36 may preferably consist in copper tubing, and is connected to a suitable water supply line 44, which enters over .ment I8 and into the tank 34 through a suitably sealed aperture. After passing into the tank '34 the supply line 44 connects with the cooling coil 36 which follows a coiled path many times around the interior of the tank adjacent to its side walls,

and finally connects to the carbonator unit 38 at 56 (see Fig. 5).

The carbonator unit 38 is located within the tank 34 and rests upon the heatin coil 40 at the bottom of the tank. A supply line 48 for .carbon dioxide gas is connected to the carbonator at 3I and enters compartment I8 through suitably sealed apertures in the same manner as the feed water sup ly line 44 describe above.

Carbonated water is drawn off through a pipe 5t connected to the carbonator at 58. The pipe 54 leads upward through the top of the tank and connects to the faucet 23.

The rack 22 is provided with a notch 53 in each side (see Fig. 1) to accommodate the supply lines on either side. In addition to the water supply line t4, and CO2 supply line :38, an electrical lead 13 and a drain pipe 52 pass through the notch 56.

Since the temperature of the refrigeration compartment l8 surrounding the tank 22 will be maintained in the vicinity of 5 F., it will be evident that the feed Water in the coil 36 would soon freeze if left standing. In order to prevent this, a heatin coil 453 is provided arranged in broad loops across the bottom of the tank 34. The coil may preferably be waterproof, lead insulated cable having a suitably resistant heating element for a core. 110 volt alternating current may provide a convenient source of power. The operation of the coil 49 is controlled by a conventional waterproof thermocouple 42 connected in series to the said coil, located in the tank 34 between one of the loops of the coil, and adjusted to pass current to the coil when the temperature of the water in the tank drops below 32 F. Conventional thermocouples of the type employed herein may readily be adapted to respond accurately to slight temperature differentials, and in this preferred embodiment the thermocouple 42 is adapted to break the heating circuit when the temperature of the water in the tank 22 reaches 33 F. It is to be noted that such accuracy of control cannot be obtained with the conventional temperature responsive valve systems.

While it might be thought that the presence within compartment it of the tank 34 maintained at a temperature near the freezing point cated at on the surface of the tank Walls on 1 the inside and provides something similar to an insulational blanket interferring with the rapid transfer of heat. At such times convection of heat directly to the metal tank wall by water circulation is eliminated, and the heat passes through the metal wall only after conduction through the ice. Since ice is a poor conductor of heat, the loss is not substantial. Experiments have shown that if the thermocouple is adjusted to admit heat accurately when the temperature of the tank 34 is in the vicinity of the freezing point of water, that it will admit heat only sev eral times an hour but for a total time of less than two minutes per hour. In view of this, efiiciency loss in the entire system during idle periods is negligible.

During periods of use, when the introduction of water into the supply line 44 tends to bring the temperature of the water in the tank 34 several degrees above the freezin point of water, the ice blanket 69 will rapidly melt and heat will commence to be drawn off rapidly by direct convection of heat to the metal tank wall by water circulation. Thus, during extended use, the unit 30 can handle rapid cooling, while during periods of idleness it rate of heat transfer is much slower.

While minor variations such as using liquids other than water, etc., will be apparent to those skilled in the art, it is not intended to confine the invention to the precise limits of the pref'erred embodiment herein shown, but rather to measure it in terms of the appended claims.

Having thus described an illustrative embodiment of my invention what I claim as new and desire to secure by Letters Patent of the United States is:

1. A combination ice cream and carbonated water refrigeration cabinet having in combination, insulated walls forming compartments, a single refrigeration mechanism adapted to main tain the cabinet at a temperature substantially below the freezing point of water, metal walls forming a separate container adapted to fit into one of the said compartments, water filling the said container, a conduit having a large surface area conveying feed water for carbonation through the said liquid in the said container, a heating means within the said container, and temperature responsive means controlling the said heating means whereby heat is admitted to the said container to maintain the temperature of the said liquid above the freezing point of water.

2. Apparatus for cooling water without freezing it comprising, a refrigeration compartment adapted to maintain temperature substantially below the freezing point of water, a tank located within the said compartment, Water filling the tank, a cooling coil serving as a conduit for the water to be cooled and being immersed in the water in said tank, means introducing heat into the tank, and a sensitive thermocouple adapted to control the introduction of heat by said means to commence at the freezing point of the water and to cease within one half degree thereabove, whereby during periods of idleness when the refrigerationload is low a thin blanket of ice will build up on the inside of the tank and retard the transfer of heat, but during periods of extended use when rapid transfer of heat is desired, a rise of temperature in the tank will cause the ice blanket to melt and permit rapid transfer of heat.

3. Apparatus for refrigerating a liquid comprising, a heat exchanging coil containing the liquid, a tank, a liquid refrigeration medium in the tank, the said coil immersed in the said medium in the tank adjacent to the wall thereof, refrigeration means adapted to extract heat through the wall of the said tank and to maintain a temperature below the freezing point of the said liquid refrigerating medium, heating means adapted to introduce heat into the said medium, and a thermocouple control for the said heating means adapted to actuate the heating means only when the temperature of the said medium is substantially at its freezing point.

4. The apparatus described in claim 3 further characterized by the said coils being arranged in close proximity to the walls of the said tank, whereby convection of the medium adjacent to the walls of the tank is substantially opposed.

ARTHUR K. SMITH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,699,613 Ebinger Jan. 22, 1929 1,973,518 Atchison Sept. 11, 1934 2,223,234 Stemme Nov. 26, 1940 2,499,736 Kleen Mar. 7, 1950

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