US1761606A - Refrigeration - Google Patents

Description

June 3, 1930. l.. F. WHITNEY 1,761,606

REFRIGERATION Filed Jan. 6, 1927 2 Sheets-Sheet l L. F. WHITNEY June 3, 1930.

REFRIGERATION Filled Jan. 6, 1927 2 Sheelzs-SheefI 2 @/4 graan? in ey -yweww/) W Z n e D j@ Patented June 3, *1930 UNITED STATES PATENT OFFICE LYMAN vIl?. WHITNEY, 0F BOSTON, MASSACHSETTS, ASSIGNOR, BY` MESNE ASSIGN- MENTS, TO STATOR -REFRIGERATION, INC., A CORPORATION OF DELAWARE REFRIGERATION Application mea January e, 1927. semi No. 159,344:

torily low temperature which will not fall below a predetermined minimum.

More specifically the present invention discloses means whereby a portion of the iiuidcontained within the refrigerating apparatus may be frozen when the temperature of the cooler goes below a predetermined minimum and may thus automatically stop the normal cyclic action of the system. Such a feature is illustrated more particularly as arranged in conjunction with a system for evaporating a liquid refrigerant by the aspiration of a heavier propellent fluid, for example, using water or water containing a solvent for the refrigerant and mercury for the propellent fluid as disclosed and described in the copending application of Eastman A. Weaver, Serial No. 733,699, led August 29, 1924, or my copending applications Serial Nos. 159,342, 159,343 and 159,345 filed on even date herewith.

h' Because of its ygreater simplicity and reliability of operation, the invention is applicable to a wide variety of installations, and it is especially advantageous when used in conjunction with a combined refrigeration and hot water heating system in the manner more particularly disclosed in the above-identified application, Serial No. 159,345, the energy imparted to the vaporizer or equivalent elenient serving at all times to impart heat to the hot water supply and also serving to provide the right degree of refrigeration to answer the individual requirements of the particular installation.v Thus the means whereby refrigeration automatically ceases and yet the' propellent fluid may continue movement about its circuit is especially desirable when a water heatin system and a refrigeration system are com ined.

'Further objects and advantageous features of the invention will be apparent to those skilled in the art upon the reading of the subjoined description and claims in conjunction with the accompanying drawings in which Fig. 1 is a diagrammatic view of a refrigerating system embodying the improvements of the present invention; j

Fig. 2 is an end View of a portion of such a system;

Fig. 3 is a top plan view of a portion of the system;

Fig. 4 is a central longitudinal section of the aspirator; and l Fig. 5 is a detailed section of amodiiication of the refrigerating apparatus.

Referring to the accompanying drawings and more particularly to Fig. 1 thereof, refrigerating apparatus which may be arranged to be automatically self-regulatin comprises a suitable cooler lof any desired form, such as a series of pipe coils 2 provided with suitable transverse plates 4() as disclosed. A refrigerant condenser or dissipator 3 is preferably located at a higher level than the cooler 1 and may conveniently comprise a series of oppositely disposed open loops formedA by a pipe having a general downward inclination in the manner shown, suitable radiating fins 5 being provided upon the pipe in order to aid heat dissipation. Condenser 3 may be cooled in any desired manner, as by exposure to the atmosphere, by an artificially induced air draft, or by circulating water.

At the lower art -of the apparatus is a vaporizer 7 whic 'is provided with a heating element, such as a burner or an-electrical resistance element 8 and supplied with current by leads 9, which is adapted to boil the propellent liquid, e. g. mercury. Boiler 7 is provided with an upstanding outlet tube 12 leading to a high pressure chamber or'elbow 10 and an aspirator nozzle 13 which is adapted to emit propellent vapor into a mixing chamber 16. A vapor duct 15 connects the into compression duct 19, which also comprisesacondenserforthe propellant. Duct 19 terminates in an upwardly directed curve, a continuation of which comprises a vertically extending tube which is connected with the separating chamber 6, Fig. 2. A suitable drain is adapted to conduct condensed propellent fluid from mixing chamber 16 back to the boiler 7 through the liquid trap 4l, and drain 25 is joined intermediate its length by the downwardly inclined pipe 26 which is connected with the lowermost part of compression duct 19 by a suitable tube 42, whereby propellent fluid condensed 1n the duct 19 may pass into pipe 26 and thus through trap 41 into the boiler. Pipes 25 and 26 are de signed to hold suitable static columns of liquid propellant in order to provide a suitable head to balance the vapor pressure in the v26 and 15 so that fluid in the tra boiler and tube 12. 0

The lower end of the condenser tube 4 1s i connected with the separating chamber 6, -into the intermediate portion of which the tube 20 vents and to the bottom of which is connected duct 21, comprising a suitable trap 23 and havingr an outlet 24 leading into cooler 1. A suitable drain for any residual propellent fluid that may be carri to the cooler is provided by the downwardly extending tube 28 which comprises the liquid trap 27 and forms a continuation of tube 26, a suitable connection 29 being provided between tubes Will not be displaced when the system is su jected to certain special conditions such as when, after being evacuated, gas is admitted to the system and so that there will be no tendency for gas to pocket when the system is being evacuated.

While the combined compression and condenser duct 19 may be cooled in any suitable manner, as by exposure to the atmosphere or to an artificially induced current of air, cool- -ing may preferably take place by circulation of water in a suitable water jacket 35 having pipe connections 36 and 37 with a hot water storage tank 38 which is connected with a suitable exterior source of water supply by pipe 39 and is provided with one or more outlets designated by the numeral 40. Pipe 36 preferably connects the lower portion of the tank with the corresponding portion of the water jacket, while pipe 37 similarly connects the upper portions of these units. If desired, a

' dra-in 47 provided with the thermostatically controlled valve 48 may be located at the upper part of the tank in order to provide an voutlet when the water exceeds a predetermined temperature, for example, when it approaches boiling temperature. As more particularly disclosed and described in my aboveidentified copending application No. 159,345, the heat absorbed from condenser duct 19 passes to the water circulating in jacket 35 and is thence transferred by the thermoliquid propellant, for exam le, mercury, be-

ing provided for the boiler ,heat is applied to the boiler and the system exhausted of air. Due to the fact that the tube 25 enters the boiler below. the level of the mercury, boiling of the mercury will cause a building up of vapor pressure in tube 12 which will be balanced by the head of static columns of mercury in tubes 25 and 26. The aspirator nozzle 13 is designed to vent the propellant into mixing chamber 6 at a pressure which will substantially equal -a vapor pressure in cooler 1 that will provide a suitable rate of evaporation to give the desired refrigerating capacity, the nozzle being shaped to ermit substantially adiabatic expansion o the propellent vapor and consequent increase in the velocity and kinetic energy thereof. The suction or entraining action of the propellent fluid will draw vapor through duct 15 from the surface of the liquid refrigerant in cooler 1, causing rapid evaporation in the cooler and a resultinglow temperature. The water vapor being entrained by the rapidly moving and heavier molecules of the propellent fluid 1s compressed in the compression duct 19 wherein the propellant is mostly condensed at a temperature considerably above the condensing point of the refrigerant.

A portion of the condensed propellant will flow back to the boiler through tube 25 and a larger quantity thereof through tube 42. The refrigerant vapor passes upwardly through pipe 2O and chamber 6 to the condenser 3, wherein it is cooled and condensed and flows down'as a liquid to tube 21, forming a head of water above the liquid trap until the fluid in the trap, if heavier than the refrigerant, as for example when the fluid in the trap is mercury, is forced out of the leg thereof, adjoining tube 21 so that the condensed refrigerant thus returns to cooler 1. Obviously the pressure in the condenser 3 will normally be somewhat higher, due to the action of the aspirator, than the pressure inthe cooler 2, and the liquid trap 23 permits the existence of this difference in pressure.

Pipe 28 is adapted to permit the drainage of any residual mercury which fails to pass down drain 42 and is carried upwardly into the refrigerant condenser and thus into the cooler 1. The trap 27 is located in tube 28 to permit the seepage or flowof mercury aspirator nozzle whereby the propellant may give up its. energy in pumping the refrigerant. In order to permit automatic self-re ation of a refrigerating system of this .c aracter and to maintain the refrigerator at a suitable temperature, for example preferably, somewhat above freezing, it is desirable to provide a refrigerant which differs in its liquid and vapor phase, for example, using water in the form of a saline or caustic solution so that.

the vapor in the cooler 'and the returning llquid substantially are pure water, while the freezing temperature o freezing point of water. Use of a refrigerant of this character in this type of refri erating system facilitatesthe automatic sel -regulation of the system. Other factors vaffecting the temperature at which the machine stops functioning are the diameterand thickness of wall of the pipe through which the returning liquid enters the cooler and the distance to which this pipe projects into the cooler.

Under such conditions let us assume that the temperature on the outer -surface of the cooler 1 has fallen below the desirable minimum-so that the articles in the refrigerator may be near the freezing point.v The Water vapor returning through tube 21 and its extension 24 will be cooled below freezing temperature atthe mouth of the duct, and consequently formation of ice will take place so that the pipe 24 will be stopped. As soon as the condensed refrigerant vapor can no longer pass from the dissipator 3 to the cooler 1 further vapor from the dissipator 3 will fill pipe 2l and overflow into the separating chamber 6 from which it will empty into the tube 20 sealing the lower end of ,ducty 19. As

soon as the condensed refrigerant thus seals the lower end of this duct it will become heated by the continued infiow of propellent v vapor which condenses in duct 19 and theremitting the continued operation of the heating element as well as heating ofthe water in tank 38, without necessity of interposmg as, for example, the ref effecting the automatic se the solution in the' cooler may be somewhat'below the normal,

a thermostatic or hand regulatedcontrol, and yet at the same timepreventing an excessivel low temperature in the region to be coole erator, and thus f-regulation of arefrigerating system.

It will be understood that continued circulation lof the mercury causes the temperature of the refrigerant column in pipe 20 to rise, .thus increasing the vapor pressure above the water column soA that the total pressure against which the refrigerant is pumping is t' still further increased. Due to this heatmg of the refri erant, vapor is continually passing upwar y from the column in pipe 20 .to the condenser 3 where it condenses again returnin as liquid through separating chamber 6 to t e column in pipe 20 as long as the ice continues to choke pipe 24. When this ice melts, the refrigerant which is constantly being evaporated from the liquid column in pipe 20 and being condensed in condenser 3 can run down p1pe 21, thence passing into the cooler through pipe 24. Thus the pressure above column 20 is relieved and all of the liquid from the column is soon evaporated` and condensedv in condenser 3, returning to the cooler and permitting the normal unobstructed aspirating act-ion of the nozzle 13.

Obviously7 therefore when evaporation in cooler 1 ceases, the cooling effect thereof is immediately halted and it tends to warm up, thus eventually melting the ice in passage 24, and permitting the system to reassume its normal cyclic action.

Instead of using caustic or other substance which does not evaporate, in the cooler for the aforesaid purpose, I may use in the refrigerant a substance such as ethylene glycol (either with orwithout caustic or the llke) which evaporates and therefore is present in the returning liquid, but which has a different concentration in the 1i uid in the cooler and in the returning liqui respectively. Under these conditions in the particular case assumed the returning liquid freezes at a lower temperature than pure Water but at a higher temperature than the liquid in the cooler so that the action of the system will be substantiall as described above except that I may in t` is way vary the temperature at which pumping action ceases and at which it again begins.

Fig. 5 shows an arrangement of piping which may be substituted for the separating chamber 6 and is particularly useful in conjunction with a pro ellant having a lower density than'the re rigerant, for example, penta ethyl benzine; In this form of the invention the duct 20 terminates in a substantially horizontal extremity which vents directly into pipe 21, this junction being located at such a height in rela-tion to the cooler that a liquid column of refrigerant, sufficient to balance the li uid in trap 23, will not overflow into pi e 60, iit so that a column formed by the lig ter propellant would overflow into pipe 60 rather than passing through the liquid trap to the cooler. The height of the outlet 60 should also be such that the wei lit of a column of refrigerant filling pi e 21 rom the trap 23 up to outlet 60 differs rom that of a similar column of propellant by an amount correspondingl to the maximum difference in pressure in t e cooler and refrigerant condenser respectively, for which the system is designed. lVhen a light propellant of this type is used, obviously the drain 28 may be omitted. v

I claim:

1. The art of refrigeration comprising the l pumping of a refrigerant by the aspiration of a propellent fluid to draw refrigerant from a cooler in its vapor phase, condensing the `refrigerant and returning it in its liquid e a cooler in its vapor phase, condensing the refrigerant and returning it in its liquid phase to the cooler, and freezing a portion of said liquid to accumulate a body of liquid between the point of aspiration and the condenser, thereby to diminish said withdrawal of refrigerant from the cooler.

3. A refrigerating system comprising a cooler, a condenser, a duct therebetween, means for pumping refrigerant ont of the cooler and concomitantly vaporizing it, sending it through a passageway to the condenser, the duct extending upwardly from the cooler and being provided with downwardly extending branch intermediate its height which leads to the outlet of the pumping means, whereby freezing of refrigerant in the duct may cause liquid refrigerant to overliow and form a liquid seal following adjoining the pumping means to provide a back pressure to retard or prevent further evaporation of the refrigerant, thereby causing the system to be self-regulatory although permitting the con.- tinued operation of the pumping means.

4. A refi'igerating system comprising a cooler, a liquid refrigerant within the cooler, a condenser, an upwardly extending duct between the cooler and condenser, a boiler containing a liquid propellant, an aspirator nozzle connected to the boiler, a mixing chamber at the outlet ofthe nozzle and below the condenser a passageway joining the cooler and the mixing chamber, a pipe concentrically aligned with the nozzle at the opposite' side of the mixing chamber, a continuation 'of said pipe joining the upwardly extending duct intermediate its extremities.

5. A household utility system comprising refrigerating apparatus which includes a circuit aving a cooler for refrigeration and a condenser, means for pumping refrigerant about the circuit through said cooler and condenser with heat supplied to the circuit, said circuit including a. portion wherein a partof said heat is abstracted from said refrigerating apparatus, said system) also comprising a hot water supply reservoir and means for supplying part of said abstracted heat to s aid reservoir, said refrigeration system being automatically self-regulating whereby pumping of the refrigerant may be retarded when its temperature-.falls below a given point but whereby heat abstraction may continue.

6. Household apparatus comprising a refrigerant circuit including a condenser as well as a cooler for refrigeration or the like, means associated therewith to pump the refrigerant about the circuit, a liquid jacket to cool the condenser, a hot water storage tank, means for transferring heated liquid from the jacket to tlie tank, and automatic means for discontinuing the cooling of the cooler when the temperature thereof falls below a predetermined minimum, said last-named means permitting the continued transfer of heat from the condenser jacket to the tank.

7. The process of providing refrigeration v and heating water for household uses or the like. which comprises aspirating a refrigerant fluid having anormal boiling temperature witlia propellent fluid having a comparatively h igh boiling temperature, passing the resulting mixture of vapors through a condenser at a tem rature above the boiling point of the re rigerant whereby the`propellant is condensed out of the refrigerant, condensing said propellant by a current of water whereby the heat of condensation is absorbed in the water, and Supplying the heated water to a point of household use, con-A densing the refrigerant and returning the same to the pointof aspiration, and preventing the free movement of refrigerant and further refrigeration when the temperature of the refrigerant falls below a predetermined minimum while continuing the supplying of propellent fluid to the condenser and the heatin of water thereby.

8. T e process of roviding suitable refrigeration and heat or a hot water supply sgstem, comprising the input of energy into t e system, normally applying the energy in part to obtain refrigeration, absorbing the energy in part in heating water for the hot water supply system, and when the desired,

refrigerating capacity is exceeded temporarily diverting the energy from refrigeration while continuing the heating of water.

9. The process of providing suitable refrigeration and heat for a hot water supply system, comprising the vaporizin of a propellent Huid and the directing 0% the same about a circuit normally to pump refrigerant by aspiration, abstraction of heat from the propellant following aspiration, transferring a part of said abstracted heat to the Water supply system, preventing the pumping of refrigerant When it falls below a predetermined temperature and meantime continuing the vaporizing of the propellant and transfer of heat to the hot Water supply system.

10. A household utility system comprising refrigerating apparatus which includes a ping said supply of abstracted heat to said' 11. Household apparatus comprising a refrigerant circuit including a condenser as Well as a cooler for refrigeration, means to pump refrigerant about the circuit, a hot water storage tank arranged to receive heat from the condenser, automatically actuable means for discontinuing cooling of the cooler `when the temperature thereof falls below a predetermined minumum, said lastnamed means permitting the continued action of the pumping means and the oontinual transfer of heat to the hot Water storage tank from the condenser.

12. The art of refrigeration comprising the pumping of a refrigerant vapor stream from a cooler to a region of condensation, there condensing the refrigerant vapor, directing a stream of the condensed refrigerant to the cooler, andfreezing a portion of said refrigerant stream in response to a predetermined low temperature of the cooler, thereby stopping normal working of the refrigerant cycle.

13. The art of refrigeration comprising the pumping of a refrigerant va or stream rom a cooler to a region of con ensation, there condensing the refrigerant vapor, directing a stream of the condensed refrlgerant to the cooler, and freezing a portion of said refrigerant stream in response to a predetermined low temperature of the coolerrand thus causing diversion of condensed refrigerant into l the path of the refrigerant vapor stream, thereby impeding the normal withdrawal of vapor from the cooler.

14. In the art of refrigeration, the method which comprises pumping refrigerant vapor from a cooler to afford a low temperature in the region of the latter, condensing the refrigerant vapor thus pumped and returning the same to the cooler until the cooler reaches a predetermined low temperature, and shunting at least a portion of the condensed refrigerant past the cooler to the region of pumping when such a loW temperature is reached.

15. Refrigerating apparatus comprising a circuit containing refrigerant and including a cooler having a vapor outlet and a liquid inlet, the portion of the circuit adjacent said inlet being subject to the lovvr temperature of the cooler and shaped to be readily closed by refrigerant freezing therein, and the refrigerant having a freezing point of the order of the minimum temperature of the cooler.

1G. In a refrigerating system comprising a circuit containing refrigerant and including a cooler having a vapor outlet and a liquid inlet, the method of regulating the temperature of the cooler which comprises using a refrigerant having a freezing point of the order of the minimum temperature of the cooler and, when the temperature reaches said minimum in response to evaporation in the cooler, restricting circulation in said circuit by freezing refrigerant in said inlet.

17. The art of refrigeration which comprises moving refrigerant vapor from a cooler to a region of heat dissipation, there condensing the refrigerant vapor, directing condensed refrigerant from said region to the cooler, and causing the formation of a crystalline deposit in the path of said condensed refrigerant in response to a predetermined low temperature of the cooler, thereby impeding normal Working of the refrigerant cycle.

18. The art of refrigeration which comprises moving refrigerant vapor from a cooler to a region of condensation, there condensing the refrigerant vapor, directing the condensed refrigerant to the cooler, and causing the formation of a crystalline deposit in the path of said condensed refrigerant in response to a predetermined low temperature of the cooler, and thus causingdiversion of condensed refrigerant into the path of the refrigerant vapor passing from the cooler to the condenser, thereby impeding the normal withdrawal of vapor from the cooler.

Signed by me at Boston, Massachusetts, this 20th day of December, 1926.

LYMAN F. WHITNEY.

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