US2500684A - Water cooler - Google Patents

Description

March 14, 1950 K. JOHNSON WATER COOLER 3 Sheets-Sheet 1 Filed April 16. 1945 March 14, 1950 H. K. JOHNSON WATER COOLER 3 Sheets-Sheet 2 Filed April 16, 1945 L. l n... r.. ..f 1.. in a. .ul t

H. K. JOHNSON WATER COOLER March l 3 Sheets-Sheet 3 Filed April 16. 1945 m T m m Patented Mar. 14, 1950 riso PATENT 'OFQ WATER COOLER Application April 16, 1945, Serial No. 588,571

13 Claims.

The present invention relates to coolers and more particularly to refrigerating mechanism by which plain or carbonated potable liquids, or both, are dispensed at a substantially constant low temperature over a wide range. of variations in the rate of withdrawal Without the liquid or liquids becoming frozen and damaging the associated conduits.

The present invention is an improvement over the cooling apparatus shown in my Patent No. 2,324,707, reference to which is hereby made to the extent that a better understanding of the present invention is concerned.

Diiculties have been experienced with conventional water coolers in keeping the temperature of the dispensed water consistently at a low temperature for good carbonation, such as 38 F. and less Without using a closed body of liquid to cushion variations and without freezing the water when withdrawal is stopped after a sustained Withdrawal. Most conventional sysstems operate at 40 F. or a little higher to avoid the dangers of freeze-ups, but those which employ a cushioning liquid or a water coil immersed in refrigerant to combat freezeups are confronted with the danger of a freezeup rupturing a conduit and causing contamination of the refrigerant line with water or the water line with refrigerant.

Although the'ability of a water cooler to carry the load of cooling water from 80 F. to 38 and less is primarily dependent upon the relationship between the horse power of the refrigerant compressor and the volume of water to be withdrawn, the maintenance of a substantially constant low temperature for the varying volumes of water that is withdrawn depends upon the construction of the water cooler.

The primary object of the invention is to provide a cooler that is brought instantly into operation when withdrawal is started, yet will deliver water constantly at substantially the same temperature under varying rates of withdrawal without danger of freezing the water when the Water flow is shut down.

Another object of the invention is to provide an improved Water cooler assembly which lends itself to rapid and commercial production and whose coils are shielded by a water-proof insulating sealer from ambient temperatures and from contact with atmosphere where humidity is present. y

Another object of the invention is to provide a water -cooling system for potable liquids which eliminates the danger of the liquid getting into 2 the refrigerant line or vice versa, and thereby requiring a complete shut down to purge them.

Another object is to provide a thoroughly ei'- cient refrigerating unit which in shape and size may be located in any comparatively small space that might be available either inside or outside a refrigerated compartment without materially affecting its operation.

The invention is further characterized by a structural arrangement in the unit by which the unit can be readily installed and removed upon occasion from a position otherwise inaccessible if space allocation requires location at that point.

Another object of the invention is to provide an insulated water cooler unit which can be installed in thewall of a refrigerated compartment in a place where insulation is usually installed, whereby space is conserved without saccricing heat insulation for the compartment.

These being among the objects of the invention, other and further objects of the invention Vwill appear from the drawings, the description relating thereto and the appended claims.

In the drawings:

Fig. 1 is a side elevationof a drinking fountain water cooler partially sectioned to show the relationship of the parts.

Fig. 2 is a vertical section taken through a portion of a refrigerating compartment illusi trating a preferred form of the invention as installed in a refrigerating compartment such as the storage cabinetV of a soda fountain.

Fig.l 3 is a plan view of one form of the invention used for carbonated water and plain water.

Fig. 4 is an end View, partly in section, of the embodimentvshown in Fig. 3. Fig. 5 is a side view, partly in section, of the form shown in Fig. 3.

Fig. 6 is a section taken upon line 6-3 in Fis. 3.

Fig. 7 is a diagrammatic section-'through the .coil assembly of the embodiment shown in Fig. 3.

The water cooler is representative of a single potable liquid dispenser where only plain water is dispensed, or a coin controlled dispenser whichv uses refrigerated carbonated water in dispensing l I by a pipe I6 and the outlet of the condenser is connected to the water cooler I1 by a conduit I8 through an expansion valve 20 (Fig. 3). The refrigerant return to the compressor is a `coni duit 2| including a pressure regulating valve 22.

Water is supplied through a connection 23 as conducted through the cooler I1 to a drinking spout 24 under the control of a self-closing hand valve 25. Any water not consumed at the foun- `tain is drained from the machine through the waste pipe 26.

The motor I3 is powered from house current through an extensim cord 21 and controlled .in `its operation in a suitable manner by a pressure control 28 responsive to the pressure of the refrigerant present in the intake conduit 2| of the compressor I2.

When the water cooler I1 is used with a soda fountain, the refrigerant can be supplied from Ithe same compressor ,that the refrigerant coils 30 are supplied, these coils being secured in heat exchange relation with the outer surface of the `inner lining 3I as insulated from. the atmosphere by a layer of insulation 32 protected in turn by a finished shell 33.

Referring to Figs. 3, 4 and 5, the coils making up the layers of conduits in heat exchange relationship shall be identified by the letter S for soda or carbonated water coils, a letter P for `plain water coils and the letter R for refrigerant coils.

The suix numeral will distinguish between the coils for each fluid and their preferred 1 order of assembly.

' All of the coils are fiat spirals, formed of tubing wound preferably in opposite directions for adjacent coils. Furthermore, the refrigerant coils R are made of larger diameter stock, such `as l/z" or more copper tubing while the water coils S and P are copper tubing. Furthermore it is desirable to make the coils of each set `so that they may be practically identical, yet

will join up with each other to form a continuous passage when turned over.

Before describing the coils and their assembly, reference is made to Fig. in which the coils as constructed are shown in solid lines and the mating or joining of each set of coils is indicated in dotted lines. In the order shown from top to the bottom of Fig. 10 a plain water coil P2 f is on the bottom followedl by coils R3, P4, R5,

PG, R1, S8, R9, SID, RII and PI2. lnumerals indicating the order in which the coils The suix are preferably assembled.

After all tubes are wound into the. spiral coils in the forms indicated, adjacent turns of each coil are tacked together by spot welds 34 to hold jthe turns of each coil securely in place. The lturns are made as tightly as possible against each other but in order to lassure good heat exchange over more than a line contact between them, the coils are placed between flattening dies and flattened on opposite sides to the approximate shape shown in Fig. 9. This operal tor (not shown) by a connection 46.

tion increases the planar area on both sides of the coils for better heat exchange, but otherwise does not distort the tube from its original position. The tube in the ilatteningoperation becomes almost square or somewhat oval because in pressing, it down, it bulges at the corners when adjacent turns mutually oppose each otherY ina radial direction. The coil expands somewhat in a radial direction, but once the amount of expansion is determined for the space to be occupied by the coil, depending upon how muchv the tubes are flattened, proper allowance can be made whereby the coil is brought up to the desired size. The ends of the tubes are left round so that connection between coils can be made quite easily.

Thus the coils are formed to a pancake shape from round tubing which is convenient to handle and then flattened for maximum heat exfchange without destroying the roundness at the ends which facilitate connections between coils. Each coil is formed in this way, the coils R and P being made out offcopper tubing and the coils S out of 18-8 stainless steel tubing to resist the action of the CO2 in the carbonated water. Before assembling, one end of each coil is burred after cutting and the end of the coil to be connected thereto is expanded outwardly sufficient to receive the burred end. During assembly, once a telescoping relationship between two ends of connected coils is established, these ends are brazed together under heat with suitable flux in a well known manner before the next coil is dropped into place.

In assembling the coils, coil P2 is provided -with a long lead extending upwardly from the center of the coil which lead 35 is bent to provide` a length 36 running parallel with the face ofthe coil for connection with a water faucet such as 24.

Coil R3 is then slipped in place over the lead 35 with the end 31 thereof pn the outer turn extending upwardly on the outside of the coils for connection with the expansion valve 20.

On top of the coil R3 is placed the coil P4 whose outlet is on the outer turn and is connected to the inlet of coil P2 as indicated at 38. Once the coils P4 and P2 are in place the connection 38 is lbrazed as already mentioned.

On top of the coil P4 is dropped the coil R5 with the inlet thereof on the inside turn connected as at 40 to the outlet upon coil R3.

Thereafter the coil P6 is dropped into place and the outlet thereof on the inside turn is connected as at 4I to the inlet on the inside turn of the coil P4. Once this connection is brazed, the coil R1 is dropped in place with the inlet thereof on the outer turn connected to the outlet on the outer turn of the coil R5 as indicated at 42.

The coil S8 is then dropped into place as provided With an outlet connection 43 leading upwardly from the inner turn and an inlet connection 44 on its outer turn. The outlet con` nection 43 is connected to a soda water draft arm or other device by which the carbonated Vwater may be dispensed as a beverage.

On top of the coil S8 is dropped a refrigerant coil R9 whose inlet upon the inner turn is connected with the outlet upon the inner turn of coil R1 by aconnection 45. The coil SIU is then placed on top of the coil R9 with the inlety thereof on an inner turn connected to a carbona- The outlet 41 upon .the outer turn of coil SIU is connected to the inlet 44 upon S8 by eta-connection 48.

A fifth refrigerant coil Rl I is then dropped into place with the inlet 50 on the outer turn thereof connected with the outlet on the outer turn of R9 by a connection indicated at 5l. The outlet connection of RH is upon an inner coil and is connected to the suction side of the compressor l2 by a connection indicated at 52. The fourth plain water coil P12 is then dropped into place with the outlet 53 thereof on the outer turn connected to the inlet on the outer turn of P6 by a connection indicated at 55. The inlet of the coil PI! is upon the inner turn as indicated at 55.

Aside from the inlet connection to the' refrigerant coil R3, which is upon an outer turn of that coil, all other connections to the carbonated water, plain water and refrigerant conduits formed by the coils are disposed centrally of the coils as shown in Fig. 3.

After all eleven coils are assembled and the intercoil connections have been brazed, the assembly is clamped together preferably by turn buckle clamps and pressure tested under water, each circuit being subjected to approximately 250 lbs. pressure per square inch. After the tests have been successfully passed, the assembly is then l dipped in a, tinning solution at high heat so that all interstices between the coils and the turns in each coil are filled with heat conducting metal 29 whereby each abutting coil or turn is in heat exchange relationship with the next abutting coil or turn.

Thereafter the unified assembly of coils is placed in a metal box 56 with the terminal connections upwardly. The coils are then covered with Water-proof insulating material. The material is preferably an odorless asphalt filler whichhasa comparatively low melting point such as 160 Fahrenheit which enables it to be poured into and around the coils without the temperature thereof in its liquid state affecting the condition of the coils.

With this arrangement as particularly shown in Fig. 3, the inlet 46 of the soda Water, the inlet 55 -lll of the plain water and the outlet 52 of the refrigerantl coil are in close proximity to one another at the point where the section 6 6 is taken upon Fig. 3. At this point the bulb 5l oi the expansion valve 20 is located and the bulb and conduits are clamped together by a band 5Bfin intimate heat exchange relationship. This heat exchange relationship is located as close to the point where these conduits enter the insulating sealer as possible.

Of special interest` is this arrangement in which the two inlets of the water circuits are bound together in intimate contact with the control bulb of the thermostatic expansion valve. The bulb being in intimate contact with the inlet of the plain and carbonated water as well as the suction line for the cooler, is instantly responsive to the temperature of the incoming water and for that reason the thermostatic valve will act instantly to supply the liquid refrigerant into the expansion coils when the water is being withdrawn. Whenever water is being withdrawn, the bulb operates to open the thermostatic valve and provide an immediate supply of refrigerant to the cooler. This control, because of the location of the valve at the inlet of the refrigerant circuit, is such that the flow of refrigerant is instantly controlled with the flow of warm water and is immediately cut oi the moment the temperature is lowered to the desired point. Furthermore, this heat exchange relation is at the very beginning of the heat exchange contact between the refrigerant line and the water coils so that the bulb is instantly responsive to the conditions developing in the coils as they occur. In some installations it may be desirable to cover the bulb with insulating sealer also, but it has been found thatthe location of the bulb immediately outside of the insulating sealer is satisfactory as long as there is no substantial space between the bulb and the point where heat exchange between the coils begins.

Furthermore, as long as that portion of the refrigerant line which is disposed outside of the insulating sealer is insulated from heat exchange with the atmosphere, the pressure regulating valve may be located any place conveniently close to or remote from the unit. This is also true of the thermostatic control valve as long as the bulb is' located where described. Suitable hand shut-off valves (not shown) may be located any place in the conduits outside of the insulating sealer but it has been found that the automatic valves illustrated in the drawing are sufficient for commercial applications.

The expansion valve is one which can be purchased on the open market and is so connected that it permits the flow of liquid into the refrigerant coils R when they are above a certain temperature. It is important in selecting the expansion valve that it have a high eiciency in its operation and that its size be small enough to be located in a comparatively smallspace.

The pressure control valve is also one purchased on the open market whose construction is such that it is provided with a bellows responsive to the differential in pressure between atmosphere and the pressure present in the refrigerant coil, which differential operates a ball check valve to open it when the pressure in the refrigerant coils exceeds a predetermined amount. For instance, in the particular embodiment illustrated where Freon gas is used as a refrigerant, the optimum pressure in the refrigerant line would be approximately 29 lbs. as the pressure to be maintained in the refrigerant line.

From the description of the coils relating to their size and assembly, it will be seen from Fig. 9 that the half inch refrigerant coil is of suflicient radial width for one turn thereof to overlap more than one turn of the smaller diameter water coils.

With this arrangement, particularly where water coils are on opposite sides of each refrigerant coil there is a normalizing effect among more than three turns of thecoils at any given turn of the refrigerant coil by which low temperatures attained under resting conditions in one coil assist the refrigerant coil in cooling water in another coil when it is being withdrawn. The tinning metal which lls the interstices assists in this cooperative action between adjacent coils and their respective turns. The size of the refrigerant coil is preferably determined in relationship to its length so that the movement of refrigerant therethrough may be suciently free that very little, if any, pressure differential exists between the pressure existing at the expansion valve and the pressure present at the pressure control valve during withdrawals.

In addition to the advantage of the overlapping relationship between one turn of the refrigerant coil and several turns of one or more water coils, the additional advantage may be attained by spiraling the refrigerant coil in a right hand direction and the water coils in the left hand direcis placed in contact with more than one turn .of

i can be framed with an insulating frame 6I.

cooling unit, after having the sealer poured in` atadas@ vthe refrigerant coil even though the water coil is of a smaller size.

Furthermore, the invention is not limited to a particular number of coils that may be present in the assembly since by the superposition of other and further coils, either including additiona1 beverage systems or further turns in a systerr which might be subjected to extra heavy loads, the cooler can be made'larger or smaller to take care of any particular condition.

It will be noted that the water cooler described has two different metals in its make-up; namely, the copper tubes and the stainless steel tubes. In those water coolers which do not have the stainless steel tubes in them, the entire assembly is hydrogen furnace brazed without a preliminary brazing of each connection as other coils are added. Under these circumstances the telescoping ends of connecting coils are merely mated and suilicient brazing metal-in the form of a ring is located at their juncture so that upon melting it will flow into the joint. The entire assembly is passed through a hydrogen atmosphere furnace as an entire unit with the brazing of all connections thus accomplished in a single operation. Furthermore, once the coil is brought up to brazing temperature it can be moved from the brazing furnace into the tinning bath to fill all interstices remaining where heat conduction would be desirable.

'The presence of the insulating sealer which completely surrounds and seals off the tinned assembly operates to prevent moisture condensing on the coils in a humid atmosphere. Furthermore it shields the refrigerating action from absorbing ambient temperatures. In addition to this the sealer is of particular Value in keeping the coils dry because it reduces possible electrolysis which might take place between the copper and stainless steel where they are brought into close proximity with each other. This is of particular interest where the stainless steel tubing and the copper refrigerant tubing are used in coin controlled dispensers for carbonated water which dispensers must be capable of sustained successful operation regardless of humidity.

Referring to Fig. 2 a further embodiment of the invention is illustrated in which the number of superimposed coils are reduced so that the height of the unit lla is approximately the thickness of the cork insulation 32 used in the refrigerating cabinet I l In this particular embodiment what is lost by reduction in number of coils, is made up for by the length' of the coils which can be varied as desired having in mind the fact that the coils must not be so long as to be cumbersome to handle during assembly operations. valves in this particular embodiment are preferably located at one end of the sealer bed in a separate cover 60 which can be removed for access to the valves when desired.

In installing this' particular embodiment, the inner wall and insulating material, preferably upon the bottom of a refrigerated compartment, are cut away to providea compartment 62 which The place is then taken from the mold and covered with a covering such as waterproof paper which is free to sleaze under the creep of the sealer when the unit is installed in place. In some installations it may be advisable to install the coils in the compartment before pouring the sealer. In either instance, however, the sealer lls up the compartment completely and serves as an insulat- The ing material that/prevents the passage of heat from outside the refrigerator to the refrigerating compartment throughV the region where the water cooler is installed. b

With this arrangement thecooling unitcan be located in otherwise dead space within the outer confines of the refrigerating cabinet without taking up any appreciable refrigerating space. Furthermore, if desirable the cooling unit can be located near the wall separating the refrigerating compartment from the compressor and the controls for the water cooler can be located in the compressor compartment where they are readily accessible.

Otherwise the unit can be located in any position as long as the pressure control valve 22 is located in a vertical position aslit is shown in Fig. 3.

By way of indicating the size of a water cooler which will lower the temperature of approximately 28 gallons of water per hour from 80 Fahrenheit to 38 F., for both plain water and carbonated water, the dimension of the unit I1 is approximately 16 inches long as taken lengthwise of the coils, 11 inches wide as taken transversely of the coils and approximately 9 inches high including the control valves and all connections as shown in Figs. 3, 4 and 5.

Consequently, having thus described the invention and several modifications thereof, it is readily apparent to those skilled in the art that various and further changes can be made without departing from the spirit of the invention, the

scope of which is commensurate with the .ap-

pended claims.

What is claimed is:

1. A water cooler comprising a plurality of spiral refrigerant coils connected in series to form a conduit having an inlet and outlet, a plurality of spiral coils for water connected in series to form a conduit having an inlet and outlet, said water Icoils and refrigerant coils being superposed one upon another alternately, and an expansion valve for controlling the admission of refrigerant to the inlet of the refrigerant conduit including a thermo-sensitive bulb, said bulb being disposed in intimate heat exchange relationship with the inlet of the water conduit l and the outlet of the refrigerant conduit.

2. A water :cooler comprising a plurality of refrigerant coils connected in series to form a conduit having an outlet, a plurality of coils for a potable liquid connected in series to form a conduit having an inlet, said potable liquid coils and refrigerant coils being superposed one upon another in heat exchange relationship, and an expansion valve for controlling the admission of refrigerant to the refrigerant Iconduit including a thermo-sensitive bulb, said bulb and the inlet and outlet of the conduits being in intimate heat exchange relationship with one another.

3. A water cooler comprising a plurality of 'spiral refrigerant coils connected in series to and outlet of the three conduits being in intimate heat exchange relationship with one another.

4. The combination defined in claim 3 the coils being embedded in a low melting point sealer, said bulb and said inlets and outlet of the three conduits being outside the sealer.

5. A water cooler comprising a plurality of spiral refrigerant coils connected in series to form a conduit having an inlet and outlet, a plurality of spiral coils,for a potable liquid connected in series to form a conduit having an inlet and outlet, said potable liquid coils and refrigerant coils lbeing superposed upon one another in heat exchange relationship, an expansion valve for controlling the admission of refrigerant to the inlet of the refrigerant conduit including a thermo-sensitive bulb, a pressure regulating valve at the outlet of the refrigerant conduit, means for disposing said bulb and the inlet portions of the two conduits close to the coils in intimate heat exchange relationship with one another and insulating means for covering said.

coils in embedded relationship to seal the coils from contact with atmosphere.

6. A water cooler comprising a plurality of spiral refrigerant coils connected in series to form a conduit having an outlet, a plurality of spiral coils for a potable liquid 'connected in series to form a conduit having an inlet, said potable liquid coils and refrigerant coils being superposed upon one another in heat exchange relationship, an expansion valve for controlling the admission of refrigerant to the inlet of the refrigerant conduit including a thermo-sensitive bulb, a pressure regulating valve at the outlet of the refrigerant conduit, means for disposing said bulb and said inlet and outlet of the two conduits in intimate heat -exchange relationship with one another at a point close to the coils, fuse metal filling the interstices between the turns of the lcoils and between the coils.

7. A Iwater cooler including a plurality of iiat spiral refrigerant coils connected in series to form a conduit having an inlet and an outlet, a plurality of fiat spiral watercoils connected in series to form a water conduit having an inlet and an outlet, said coils being superposed alternately upon one another, and means for holding said conduit coils in heat exchange relationship including a heat conducting material filling the interstices between coils.

8. In a refrigerator having a refrigerant expansion conduit for cooling the interior thereof and an insulated wall covered by a finishing shell, a compartment in said wall next to said shell and opening into the interior of said refrigerator and a mechanically refrigerated water cooler unit including a plurality of water and refrigerant coils,

said coils being embedded in heat insulating material disposed in'said compartment against said shell.

9. In a refrigerator cabinet having an outer shell and an insulating material disposed in- Mardly thereof; conduit means disposed within the coniines of the insulating material for refrigerant; means for expanding refrigerant in said conduit means including an expansion valve having a thermosensitive bulb; and a second conduit means for a potable liquid within the connues of the insulating material in heat exchange relationship with the iirst conduit means;

the outlet of the first conduit means, the inlet of the second conduit means and said bulb being secured together in intimate heat exchange relationship.

I 10. A cooler Acomprising a plurality of fiat spiral refrigerant coils connected in series to form a refrigerant conduit, a plurality of flat spiral beverage coils connected in, series to form a beverage conduit, said coils being superimposed one upon another in the form of a cylindrical stack and each individual refrigerant coil being separated from the individual refrigerant coil connected next in series by one of said beverage coils, and means for holding said assembled coils in heat exchange relationship.

l1. A beverage cooler comprising a pluralityv of flat spiral refrigerant coils and a plurality cf flat spiral beverage coils, said refrigerant coils and said beverage coils being superimposed alternately one upon another to form a cylindrical stack, the ends of each of said refrigerant coils being connected to those of adjacent refrigerant coils in series to form a refrigerant conduit, the ends of each of said beverage coils being connected to those of adjacent beverage coils in series to form a beverage conduit, and means for holding saiid assembled coils in heat exchange relationsh p.

12. A cooler comprising a plurality of flat spiral refrigerant coils and a second plurality of flat spiral coils for a fluid to be cooled, said coils being superimposed in heat exchange contact one upon the other in the form of a cylindrical stack, the refrigerant coils and the other coils being alternated so that each refrigerant coil is separated from the next refrigerant coil by one of the other coils, the ends of the refrigerant coils being connected to one another forming a continuous refrigerant conduit and the ends of the other coils being connected to one another forming a )continuousv conduit for the iluid to be cooled.

13. A cooler comprising a refrigerant expansion conduit and a second conduit for fluid to be cooled, spaced portions of said refrigerant conduit and spacedportions of said other conduit being wound into flat spirals and the individual spirals of the refrigerant conduit being interposed between the individual spirals of the other conduit in heat exchange contact.

HERMAN K. JOHNSON.

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

UNITED STATES PATENTS Number Name Dateeo 1,965,553 Lear July 3, 1934 2,039,188 Reeves '-Apr. 28, 1936 2,042,418 Askln May 26, 1936 2,142,856 Lieb Jan. 3, 1939 2,267,819 DiPietro Dec. 30, 1941 es 2,276,811 Ward Mar. 17, 1942 2,324,707 Johnson July 20, 1943 2,400,135 Quinn May 14, 1946 FOREIGN PATENTS Number Country Date 804,881 France Aug. 10, 1936

Images