US1802396A - Liquid cooler - Google Patents

Description

April 28, 1931. H. w. TAYLOR ET AL 1,802,396

LIQUID COOLER Filed May 28. 1928 2 Sheets-Sheet 1 HHLEEY N- r/man Jaw-5 7'- 5mm April 28,-1931- H. w. TAYLOR ET AL LIQUID COOLER Filed May 28. 1928 MM, %M$

2 Sheets-Sheet 2 HHLSEY w-rnrmn 140155" T- 5M/TH than! Wmmnm m Patented Apr. 28, 1931 UNITED STATES PATENT OFFICE HALSEY W. TAYLOR, OF WARREN, AND J'Am T. SMITH, OI CLEVELAND, OHIO; SAID SMITH ASSIGNOR TO THE HALSEY W. TAYLOR COMPANY, OF WARREN, OHIO, A. COB- PORATION' OF OHIO LIQUID COOLER Application filed May 28, 1928. Serial No. 281,083.

The present invention pertains to liquid cooling apparatus, of the type and kind shown and described in our joint application for patent filed on the 30th day of June, 1927, Serial No. 202,553, now matured into Patent No. 1,689,461. In general our object is to provide a small and compact cooling apparatus or unit having a large capacity and capable of being operated safely and economlcally. Thus the apparatus is de signed to cool a stream of drinking water or any liquid delivered through pipes under pressure, rapidly and efiiciently, and in addition to store the cooled liquid in substantial volume and hold it at a low temperature automatically for rapid delivery in large quantities when sudden heavy demands are made or peak loads must be met, as at meal times or rush hours in ublic places, factories, etc. As arranged and constructed the apparatus will permit re eated heavy withdrawals from the store su ply and effect automatic replacement by a resh supply which is cooled gradually before entering the storage receptacle while flowing in a thin stream thereto. The storage receptacleis preferably encased within an insulated cabinet, and consists of a closed tank or expansion drum surrounded by a double pipe cooling coil through which an evaporable refrigerant flows countercurrent to the liquid to be dispensed, whenever a given amount of liquid is withdrawn. Also, the refrigerant is delivered automatically and caused to evaporate rapidly in the cooling coil whenever the water becomes warmer than desired for drinking purposes. However, the liquid is not permitted to reach an ice-forming stage in either the pipes or the tank, as we provide automatic means to control and time the operation of the refrigerating system to prevent freezing.

On the other hand a relatively close temperature differential is maintained between the refrigerant and the liquid where-delivered from the cooling coil, thereby increasing the efficiency of the apparatus and working economy in operations.

In connection with the foregoing it should be also understood that the double pipe coil permits the refrigerant and the li uid under cooling treatment to flow throug separate channels, and that the counterflow of the respective fluids are separately controlled and regulated by separate thermostatic devices to safeguard operations and to maintain a desired working condition within the apparatus. Safeguards are also provided to prevent condensation and precipitation of water in the region of the drinking fountain bowl and valve devices within the top of the cabinet. Furthermore to prevent the return of liquid "refrigerant to the compressor, the cooling coil is preferably placed axially in a horizontal lane to trap any liquid refrigerant remaining in the coils. However, we do not limit ourselves altogether to that horizontal arrangement of coil, viewing the invention in its broader as ects, nor is the invention limited necessari y to any particular 7 form or kind of valve, switch, refrigerating device, or the like, wherever used in the working aggroupment or assembly.

For an exemplification of one working aggroupment or assembly of parts, reference may be had to the accompanying drawing, in which Fig. 1 is a sectional view, on a reduced scale, of an insulated drinking fountain cabinet, containing a water cooling and dispensing apparatus constructed according to our invention. Fig. 2 is a sectional view, on an enlarged'scale, of an expansion valve and thermostatic valve, connected to a double pipe coil or heat exchanger, which in this view, is placed in an u right position. Fig. 3 is a sectional view 0 a thermostatic valve for regulating the flow of water through the system. Fig. 4 is a sectional view of the double pipe coil.

The invention comprises a portable cabinet 2 having separate upper and lower compartments 3 and 4, respectively. The lower compartment houses a small refrigerating plant or unit A of a known t and the upper compartment is insulate and contains a horizontally-disposed cylinder or storage tank B encircled in part by a tubular heat exchanger or cooling coil C made of double tubing, preferably cop Thus a small tube 5 is s eeve r tubing. within a mo slightly larger tube 6 to provide separate concentric passages for circulating a thin stream of water and an evaporable refrigerant in intimate heat exchange relation. The inner tube 5 conveys the refrigerant, and the outer tube 6 is corrugated longitudinally to contact with the inner tube at a plurality of places to foster heat exchange and to provide a series of narrow annular channels to conduct several fine streams of water lengthwise between the tubes. The opposite extremities of the inner tube 5 ro- 'ect through separate terminal fittings 7' aflixed to the extremities of the outer tube, and the water enters fitting 7 by way of an intake pipe 8 which is connected to a source of supply under pressure, for example, a. municipal service or supply pipe. A strainer 9 may be used to prevent intake of foreign particles, and a check valve 10 is also connected to intake pipe 8 to prevent the water stored in tank B from backing out should a reduction of pressure occur at the supply source.

After the water enters fitting 7 it is cooled gradually as it passes through the coil. Assuming the temperature of the water at the source of supply to be approximately F., and it is desired to cool it to 50 F., the water in passing through the coil would be cooled in successive stages or by degrees.

until it was delivered at 50 F., at the exit fitting 7 of the coil. A temperature of 50 F., or any other desired temperature, may

be obtained in this system by using a uickacting thermostat valve D to control t e inflow of the refrigerant into inner tube 5 of the cooling coil. Moreover, the cooled water is discharged from the coil where the refrigerant enters, and a close temperature differential is maintained at this point, as will be hereinafter explained.

After leaving the coil the water passes through a fitting 10 to two branch pipes 11 and 12, which connect with a valved drinking fountain nozzle 14 and a faucet 15 res ectively. A branch pipe 16 connects dis- 0 large pipe 12 with the bottom or lower part of tank B in which a large amount of cooled water may be stored under pressure. A thermostatic valve E is also placed in one of the discharge pipes, say in pipe 10,, the purpose of which, briefly stated, is to regulate the rate of flow of the water and prevent too frequent operations of the compressor 17 which forms a working part of the refrigerating plant or unit A.

The outlet or suction end 18 of the inner coil of pipe 5 .for the refrigerant is connected to the suction manifold of compressor 17, and the compressor in turn connected by a pipe 19 to a suitable condenser 20 from which the liquefied refrigerant is conveyed by a pipe 21 to an automatic expansion valve F which may be attached directly to the body of thermostatic valve D, aadelineated in Fig. 2.

Expansion valve F may be of any desired kind or type suited to the refrigerant in use, and as shown, comprises a needle 22 which is pressed to the valve seat by a sprin 23 when the pressure within the valve bofy is increased sufliciently to act on a diaphragm or bellows 24 to .overcome the resistance of a heavier spring 25.

Thermostatic valve D comprises a nickacting shut-off valve member 26, which is pressed to its seat by a pair of springs 27 and 28 respectively. A dished diaphragm 29 and an expansible bellows 30 form art of the walls of a fluid chamber 31 whicr is connected by a pipe 32 to a bulb 33 containing an expansible fluid. Bulb 83 is clamped in contact with one or more of the pipe coils of heat exchanger C, preferably in one of the grooves of outer tube 6 (see Fig. 4) or be tween two tubes so that the temperature changes therein effect the expansible fluid to operate valve D. The coupling 34 for valve member 26 is made of two sleeved arts which permits valve 26 to remain seate for an interval while the bellows and diaphragm are being acted upon by the expansion of the fluid in chamber 31, but when diaphragm 29 straightens it buckles outwardly with a sna movement which unseats valve member 26 vrully and completely, thus permittin the refrigerant to enter the inner tube 5 o coil C without restriction or restraint.

The stream of refrigerant moves rapidly through inner tube 5, evaporating as it travels, at practically uniform pressure and consequently uniform temperature until near the exit end of coilC when it has completely passed into a vapor. The latent heat of vaporization is supplied by the water flowing counter-current around and lengthwise of the inner tube and coolin of the water results. There is a slight di erence in ressure between the entrance and exit 0 the refrigerant due to tube friction but the pressure is fairly constant within two pounds per square inch.

The capacity of any refrigerating machine is in direct ratio to the suction ressure of the compressor. The higher t e suction pressure 1n lbs. per sq. in. the greater the capacity. The factor which limits the suction pressure (i. e. the pressure at which the liquid refrigerant is evaporating) is the temperature of exit water desired. The difference between actual evaporating refrigerant temperature and exit water temperature is referred to as lag. It is obviously vital to any such device to have a lag of zero or as near to zero as possible. In the present system the lag is only 3 or 4 E, which means that the heat exchange is so intimate and rapid (due to the fact that both refrigerant and water are moving rapidly over izo Ice

a lar surface with only a thin wall of material of high thermal conductivity separating them) that the exit water assumes a temperature within 3 or 4 of the evaporating refrigerant.

Beverages which are to be drunk are best at temperatures between 35 and In this device if the exit temperature of the beverage is 50 F. then the evaporating refrigerant would be at 46 with a corresponding suction pressure of about 16 or 18 lbs. per sq. in. If the heat exchange was so slow as to have a lag of 20 (as in some types) the refri erant temperature in the above case would be 30 and suction pressure 4 to 5 lbs. with consequent decrease of com ressor ca acity.

The unction of the expansion valve F is to reduce the pressure of the refrigerant to a predetermined pressure before admittin it to the cooling coil and to maintain suc predetermined pressure by increasing or decreasing (even to a point of complete shut off) the stream of refrigerant maintaining a constant pressure since it is the natural law of liquids to evaporate at temperatures dependent on pressure. 7

Three parts of the apparatus are dependent on one another for the even operation i. e. (1) the expansion valve maintains the stream of evaporating refrigerant at an even pressure and consequent even temperature (2) the water surrounding the refrigerant tube supplies the heat units to cause vaporization of the refrigerant, and (3) the compressor removes the vapor of the refrigerant as fast as it is formed to make way for the formation of more vapor.

Now referring to the operation of thermostat valve D, preferably this is a quick opening and closing valve which is actuated by change of temperatures of the exit water from the coolin coil. The bulb 33 is filled with a fluid w ich expands or contracts greatly with raising or lowering of temperatures, and being clamped in contact with the cooling coil it is subject to the same temperature changes as the water in the coil. If the water temperature rises above a predetermined temperature the fluid in the bulb expands and exerts a pressure which opens the valve D thereby admitting liquid refrigerant to the coohng coil with resultant cooling effect. If the water ten'rperature falls below a predetermined temperature the fluid in bulb 33 contracts and valve D closes and shuts off the stream of refrigerant, and the cooling process stops.

refrigerant and cooling starts. When water a stream of stops flowing through the coil the valve D remains open until the water is cooled to the desired temperature whereupon it closes again.

The operation of compressor 20 is intermiitent, an automatic switch'G, see Fig. 1, bein used to start and stop the motor H which operates the compressor. Thus when the water in coil C reaches the low tem- C and thermostat valve D opens and admits the refrigerant, the pressure in the coil increases and switch G is effected and again operates to start the motor and compressor.

Inasmuch as the present apparatus includes a storage tank B for the cooled water, means are also provided to regulate theraie of flow of the cooled water after it passes from the coil. in connection with t e present apparatus comprises a thermostatic valve E, see Fig. 3,. which includes a spring pressed valve member 37 connected to a thermo-coupling 38 confined within the valve body. This particular valve is only one device which can be used for the purpose, and further detailed description thereof is unnecessary. Suflice to say, it regulates the flow of water after leaving the coil.

Thus, say the capacity of compressor 17 is such that it will be operating at full load when cooling water from to 50 at the rate of 10 gallons per hour. Assume that the system is just being started up and regulating valve E is set to allow 10 gallons per hour at 50 F. to pass through pipe or fitting 10, with tank B filled with air at atmospheric pressure and the water pressure in the supply line is 60 lbs.'per square inch. As the discharge pipe 12 is connected to tank B at 16, near the bottom, the air in the tank is trapped and compressed by the incoming water until eventually the pressure of the air and water in the tank is the same as the pressure of the water in the supply line.

The regulating means shown Without valve E the rate of flow of the "tank B. Thus as tank B is gradually filled there is a gradual increase of pressure, and

the tendency is to retard the rate of flow.

The slower rate of flow decreases the lag between the exit water temperature and the refrigerant temperature, thereby causing a lowering of exit water temperature due to the increased time of contact in the coil. Regulating valve E, however, then opens so as to produce a greater flow to compensate for the increased pressure against which the stream of water is delivered into the tank. Accordingly the tank can fill up without causing the compressor to short cycle, that is, to start and stop repeatedly. x

The tank functions as follows: In a water dispensing apparatus, such as a drinking fountain, the demand is spasmodic; many people may drink in rapid succession in a few minutes. Then the apparatus may be inactive for a long period. During the active or peak period the demand quite frequently exceeds the capacity of the system and the excess is supplied in this case by tank B.

Another function of the tank is viz; In a drinking fountain an ideal or desirable rate of flow of a stream of water is about 40 to 50 gallons per hour. A larger stream usually means waste, and a smaller stream does not sup ly water-fast enough. To deliver the deslred amount of cold water continuously and directly from cooling coil C uires a compressor of large ca acity, but using a tank and automatic devices as described a smaller compressor can be used as the pro or amount needed at the fountain is supplied automatically from the tank B.

A suitable valve 13 adapted to be controlled manually is placed in branch pipe 11 to control the discharge of water at the drinking nozzle 14, and an automatic regulating valve I is also used in this discharge line to control the outflow independently of the pressure in tank B. Furthermore, a spring pressed relief. valve J may be used in branch connection 12 or 16 to prevent withdrawal of allof the water in tank B.

Nozzle 14 and the body of valve 13, including the pipes and fittings for the overflow bowl 39, are embedded within cork or other insulating material 10 placed within a separate chamber beneath the metal top 41 of cabinet 2, and this arrangement is very advantageous as it prevents condensation and the collection thereof at the bottom of the bowl and beneath metal top 41.

, Bowl 39, for a similar reason, is set within a recess or opening in top 41, so that its bottom is beneath metal top 41.

Tank B and coil C are shown in Fig. 1 arranged horizontally, but these parts may also be disposed vertically. However, when mounted horizontally as shown, each convolution of the cooling coil traps a portion of the liquid refrigerant, providing complete evaporation thereof has not taken place during operations, thus preventing the refrigerant from being returned to the coml pressor in a liquid state.

We claim:

1. In a refrigerating ap aratus, a storage receptacle, a liquid circu ating coil-encircling said receptacle in delivery connection therewith, and automatic means for circulating a refrigerant at intermittent intervals in heat exchange relation with the liquid passing through said coil.

2. A liquid cooler, comprising a closed receptacle for storing a supply of cold liquid under pressure, means for delivering a stream of liquid under pressure to said receptacle, refrigerating means for cooling the stream of liquid in its passage to said receptacle, means to permit withdrawal of the cooled liquid, and means controlled by the temperature of the liquid for automatically regulating the volume of liquid flowing in a stream to said receptacle.

3. A liquid cooler, comprising a closed receptacle, means for delivering a stream of liquid under pressure into said receptacle including automatic means controlled by the temperature of the liquid for maintaining a constant supply of liquid under constant pressure within said receptacle under intermittent withdrawal of liquid therefrom, and refrigerating means for cooling said supply of liquid, the pressure of said supply of liquid within said receptacle being controlled by the pressure of said delivery stream.

4. A liquid cooler, comprising a closed dispensing receptacle, valve controlled dispensing means for said receptacle and a double pi e coil through which separate streams 0 li uid and a refrigerant may be circulated in eat exchange relation, the intake end of the liquid circulating coil being connected to a source of supply under pres sure, and the discharge end thereof being connected to said closed receptacle and said valve controlled dispensing means, and the coil for the refrigerant being connected in a refrigerating system.

5. A liquid cooler, comprising two sleeved pipes adapted'to permit separate streams of liquid and a refrigerant to flow therethrough in heat exchan e relation, a storage vessel connected to tl ie discharge end of the liquid circulating pipe, means for discharging the cooled liquid from said vessel, means for automatically regulating the flow of liquid through the heat exchanger, and means for circulating a refrigerant automatically at intervals through the second pipe of said heat exchanger.

6. In a liquid cooler, a cooling coil consisting of sleeved pipes through which separate streams of liquid and a refrigerant may be circulated in heat exchange relation, 8.

closed storage vessel encircled by said cooling coil, the liquid circulating pipe in the closed vessel connected to the liquid circulatin pipe adapted to store a part of the cooled iqu1d therein, a thermostat valve to control the flow of the cooled liquid to said vessel, a discharge connection for said coil and vessel, means for passing a refrigerant through the refrigerant circulating pipe of said cooling coil, and valve means to automatically control the flow of the refrigerant passing to said cooling coil.

8. A li uid cooler, comprisin a closed vessel having discharge and inta e connections, a cooling coil composed of two sleeved pipes, one of which is arranged to discharge 1 a liquid under pressure to the intake connection for said vessel, means for circulatin a refrigerant through the other pipe of sai coolin coil, and an ex ansion valve for contro 'ng the flow o the refrigerant through said cooling coil, said valve including regulating means adapted to be activated bylthe temperature present in the cooling C01 9. A liquid cooler, comprising a closed storage vessel, a cooling coil composed of two sleeved pipes coiled jointly around said vessel, one of said pipes being connected to discharge a liquid under pressure into said vessel and to deliver the cooled liquid outside of said vessel, and the other pipe in said cooling coil being connected in and to an automatic refrigerating system.

10. A liquid cooler, comprising a liquid container, a heat exchanger situated in heat exchanging relation to said container, said heat exchanger being connected to a source of liquid supply under pressure and also connected to deliver the liquid to said container under pressure, and said heat exchanger being also connected to a refrigerating system to circulate a refrigerant therethrough, including means for controlling the flow of the refrigerant through the heat exchanger automatically by the temperature of the liquid being dispensed.

11. A liquid cooling apparatus, comprising a cooling coil connected to a source of liquid under pressure, a closed receptacle connected to the discharge end of said coil, a discharge connection for said receptacle, and automatic means for maintaining the cooled liquid in said receptacle constantly under relalssurg. h

ui coo 'n a arat com rising a closdll vessel, aoo g cdilcorindhted to said vessel, means for passing a refrigerant through said coil, automatically at intermittent interva1s,.and automatic means controlling the discharge of liquid from said coil to said vessel.

13. A liquid cooling apparatus, comprising a storage vessel havi valved delivery connections, a cooling coil 1n discharge connection with said vessel, and a thermostatic valve automatically regulating the rate of flow of the cooled liquid passing from said coil to said vessel.

14. A liquid cooling apparatus, comprising a dispensing vessel for storing a liquid under pressure; a heat exchanger connected with a source of liquid under pressure, having liquid discharge connection with said vessel; automatic refrigerating devices connected with said heat exchanger; and means for automatically regulating the flow of liquid between said heat exchanger and vessel to com ensate for changes in pressure within said vessel.

15. A liquid cooling apparatus, comprising a storage receptacle for the cooled liquid; a heat exchanger discharging liquid.

. tac e under pressure into said rece and automatic appliances for circuiiating a refrigerant intermittently through said heat exchanger; including an expansion valve and quick-acting thermostatlc means for controlling the intake of the refrigerant into said heat exchanger.

16. A liquid cooling apparatus comprisin a heat exchanger through which a refrigerant and the li uid to be cooled flow counter-current; re rigerating appliances for circulating the refrigerant throu h said heat exchanger intermittently, inclu g an automatic starting and stopping device; an expansion valve and thermostatic means controlling the intake of the refrigerant into said heat exchanger; and means controlling the flow of the cooled liquid through said heat exchanger.

17. A liquid cooling apparatus, a heat exchanger connected to a source of liquid under pressure and to a refrigerating system, an auxiliary storage receptacle for the cooled liquid; liquid dlscharge connections for said heat exchanger leading to said receptacle; automatic means operable by the temperature of the exit 1i uid, for controlling the intake of the refrlgerant into said heat exchanger; a valved delivery fitting connected to said discharge connections; and,

means for regulating the flow of the liquid after it passes from the heat exchanger.

18. A liquid cooling apparatus, comprising a cooling coil made of two sleeved pipes to provide separate circulating passages for a refrigerant ande liquid, each pipe having separate intake and outlet connections; in combinatien with a refrigerating system, ineluding an'expansion valve an a thermostatie valve at the refrigerant intake connection for said coil said thermostatic valve having a thermo-eiemem in contact with said coil.

In testimony whereof We afix our signa- 10 tures. W T

HALSI- fill OR. JAMEE

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