US2280273A - Refrigeration - Google Patents

Description

April 2.1, 1942.

R. s. TAYLOR REFRIGERATION Filed May 14; 1946 Eiiiiiiiiiiiiiiiiiiiiiiiiiiiib iiiiiiiiiiiiiiiiiiiiiiiiiiiib 44 I I F o7 I x X l3 55 42 6?l 62 64 37 63INVENTOR 65 AQ'ATTORNEY Patented Apr. 21,1942

,UNITED STATES PA ENT OFFICE,

REFRIGERATION Robert s. Taylor, Evansville, Ind., assignor to Serve], Inc., New York, N. Y., a corporation of Delaware Application May 14, 1940, Serial No. 335,077

g 9 Claims. (Cl.'62--125) The presentinvention relates -tcthe art of refrigeration, and more particularly to a new and improved system for transferring heat to efiectcooling at a regionabove a source of refrigeration.

One object of:.the present invention isto provide a new and improved heattransfer system I r of the general type above referred to.

Another object is to provide a heat transfer system of the above type, having new and improved. means for raising liquid refrigerant from a lowlevel to a higher level without resorting to the expedients of mechanical power pumps or other similar power means.

Another object is to provide a heat transfer system of the above type, in which the number of valves for raising liquid refrigerant to a higher level is reduced to a minimum Another object-is to provide a heattransfer system of the above .type, in which refrigeration loss is reduced to a minimum. 7

Another object is to providea new and improved device for creating liquid lifting vapor pressure.

Another object is to provide a heat transfer system of theabove type, having a'liquid refrigerant lifting device, which is of simple, rugged and practical construction, which is more positive and more dependable in operation than for example a simple syphoning arrangement, and which is well suited to meet the requirements of economical manufacture.

refrigeration for said chamber. This primary evaporator unit III is shown of the type comprising a cylinder l3, enclosed in a heat insulated shell l2, and provided at its upper end with an annular tray i4; into which is delivered a suitable volatile liquid refrigerant such as ammonia by means of a pipe i5. This ammonia overflows from the tray 14, over the outer rim thereof or through porous or wire mesh outer walls thereof, and then passes downwardly along the sides of the cylinder i3.

A suitable inert gas such as hydrogen is admitted into the cylinder i3 through an inlet I 6, and flows upwardly to the top of the shell i2,

and then downwardly along the outside of said a cylinder to diffuse the ammonia. The eflect of 1 introducing hydrogen into the evaporator unit H1 is to reduce the partial pressure of the ammonia vapor in accordance with Dalton's law of partial pressures, andto cause evaporation of the ammonia with consequent absorption of heat from the surroundings.

The mixture of ammonia vapors andhydrogen is discharged from the bottom of the shell I! through an outlet l1, and delivered to the other parts of the primary refrigerating system. These other parts may comprise generally an ab- L sorber into which the mixture of ammonia va- Various other objects of the invention'" will be apparent from the following particular description, and from an inspection of the accompanye ing drawing, in which-- Fig. 1 is a diagrammatic view, partly in side elevation and partly in' section, showing a refrigerating system embodying my invention,

Fig. 2 is a vertical section of a combined primary evaporato'runit and secondary condenser unit, forming part of the system indicated in v Fig. 1, but shown on a larger scale,.

pors and hydrogenis delivered forabsorption of the ammonia into a liquid absorbent such as water. The separated inert hydrogen gas is returned to the cylinder l3 through the inlet l8, while the enriched absorption liquid is conductedto a generator. Ammonia is then expelled from the absorption solution by heating of the generator. This expelled ammonia is liquifled in a condenser, and then returned to the evaporator unit. l0 throughthe conduit l5 to complete the.

cycle in the primary refrigerating system. The weakened absorption solution from which the ammoniahas been expelled is conducted from the generator to the absorber to absorb am- Fig.'3 is a longitudinal section through a vaporizing unit of a refrigerant liquid lifting device, forming part of the system indicated in Fig. 1, but shown on a larger scale, and

Fig. 4 is a transverse section taken on line 4 -4ofFig.3.. p s

' The invention is shown in connection with a primary refrigeratlni system or the Platen- Munters absorption type. having an evaporator or cooling .unit ll, which is located remotely below a heat insulated region or chamber H to be refrigerated, and which constitutes a source of the invention are concerned may be of any other I monia gas.

The primary refrigerating system, which is not completely shown in the drawing for the sake of simplicity; forms per se no part of the present invention, and as far as certain aspects of suitable type.

The secondary system for transferring the heat from the storage chamber u to be cooled to the primary evaporator unit I I0 comprises avsecondary evaporator unit 20, disposed insaid chamber, and shown-oi the flooded type with a headeror receiver 2|, and a finnedserpentined coil 22 connected to said header. 1

The secondary heat transfer system also in- I cludes acondenser coil 23, forming with the secondary evaporator unit part of a closed fluid circuit containing a suitable volatile refrigerant. Thiscondenser coil 23 is disposed below thesecondary evaporator unit 20, and is arranged around the cylinder 3 so that the liquid ammonia in the shell l2 overflows from the tray M in sheet-like form over the successive turns of said coil. Refrigeration resulting .from the evaporation of the ammonia in the primary evaporator unit I cools thecondenser coils 23,

and thereby causes evaporation of the liquid refrigerant in the secondaryevaporator .unit 20, and resultant cooling of the storage chamber II.

The vapor flows from theevaporator unit 20 means must be provided to return the condensate liquid in the secondary heat transfer system from thecondenser 23 to said evaporator unit, so that this system is cyclically operated for continuous cooling of the storage space H. For that purpose, the refrigerant condensate from thecondenser 23 fiows by gravity down along apipe 25 and through acheck valve 26, and is discharged into a vessel orreceiver 21 forming part of a liquid lift device for returning the condensate to the evaporator header 2|. The outlet side of thisreceiver 21 ,is connectedto the evaporator header 2| by means of ariser pipe 28.

Means are provided for intermittentlycreating sufllcient vapor pressure in thereceiver 21 to force the liquid in said receiver out through theriser conduit 28 and into the header 2|. In the specific form shown, said means includes anauxiliary condenser 29 in the form of a coil, arranged in the low temperature section of the primary evaporator unit ||l so as to operate at a. lower temperature than thecondenser 23. For that purpose, theauxiliary condenser 29 is arranged above themain condenser 23 and around the cylinder l3. The upper end of thisauxiliary condenser 29 is connected to the upper end of thereceiver 21 by means of apipe 30. The lower end of this auxiliary condenser is connected to an intermittently operated vaporizing device 3| by means of apipe 32.

The vaporizing device 3| comprises avessel 34,- shown in the form of a horizontal cylinder drum,

and having centr'ally at its top an inlet to which thepipe 32 is connected. Thevessel 34 is provided in the interior thereof with a surface which is hot enough to vaporize the refrigerant of the secondary heat transfer system when said refrigerant is dumped in thermal contact therewith as will be described. For that purpose, the

'vessel 34 can be kept at a vaporizing heat by means of a. regulatedburner 36, sothat the'innerwall surface 31 of said vessel will constitute the refrigerating vaporizing surface of the device. The vaporizing heat may be supplied to thevessel 34 by any other suitable source, as'for instance by means-of the circulation of the outlet water in thermal contact with saidvessel 34. If the hot water pipe extends into the interior of thevessel 34, the outer surface of said pipe will serve as the refrigerant vaporizing surface, and may impart sufficientheat to the' walls of thevessel 34, so-that these walls also serve as refrigerant vaporizing surfaces.

If thevessel 34 is located in a warm room, the heat of this room may be suflicient to maintain the walls of this vessel at a vaporizing tempera.- ture, without necessity of additional heating means.

Means are provided in the interior of thevessel 34 for collecting the'refrigerant condensate as it is discharged into said vessel through the inlet 35, and supporting it away from the refrigerant vaporizing surfaces of the device until said refrigerant is dumped into' thermal contact with said surfaces. In the specific form shown, this means comprises a receptacle 42, divided by acentral plate 43 into a pair of adjoiningsimilar buckets 44 and 45. Thispartition plate 43 is desirably shaped witharcuate side edges 46, a flat bottom edge 41 secured to a frame bar 48, and aflat top edge 50. tacle 42 is shown formed by a pair of fiat plates 5|, diverging slightly upwardly from the frame bar 48, while the side walls of said receptacle are shown formed bycurved plates 52, extending from the arcuate sides of thepartition plate 43 and alongthe sides of the respective bottom plates 5|. Theseside plates 52 taper towards the outer edges of the bottom plates 5|,'so. that the twobuckets 44 and 45 will be substantially scoop-shaped as shown.

The receptacle 42 is pivotally supported for tilting movement desirably by means oftrunnions 55, joumalled into the opposite ends of the frame bar. 48, and extending axially inwardly fromscrews 56 respectively, these being threaded intorespective bushings 51 on the sides of theves sel 34.

'The receptacle 42 is tilted from the position shown in Fig.3 to a reverse position with respect thereto, and is yieldably held in either one of these two extreme positions by means of a spring snap device, desirably comprising aleaf spring 60, compressively coiled as shown, and having its upper end anchored in a V-shaped recess in the lower edge of the frame bar 48, and having its lower end anchored in a V-shaped recess of a headed pin 6| The tension of thisspring 60 may be regulated by means of astud 62, which is threaded in a bushing 63- on the lower side of thevessel 34, and which serves as a seat for the headof the pin 6|, and asa journal .for the dependingshank 64 of said pin. Aplug 65 may be threaded in the lower end of thebushing 63 to close said bushing.

The lower end of thespring 60, and the pivot axis of thetrunnions 55 are in substantial vertical alignment along a common center line A, while the lines of action of the frame bar 48 and of said spring meet at the point B on either side of said center line in either extreme tilted position of the receptacle 42. By means of this arrangement, the snap device described operates as a springtoggle.

In' order to predetermine the two extreme tilted positions of the receptacle 42, limiting stops are provided, desirably in the form ofcurved plates 61, connected to the outer ends of the bottom bucket walls 5| respectively, and adapted to engage the top wall of thevessel 34 in said extreme positions. Thesecurved plates 61 have a The bottom wall of the-recepcertain spring action, so that they act as bumpers to dampen the shock caused by thesnap stop engagement of these plates with thetop wall of thevessel 24; f

It should be noted that the receptacle 42 is pivotally supported near the heel of the two component scoop-like buckets 44 and 45, so that the liquid in the buckets in filling position has its center of gravity spaced horizontally from the vertical plane of thepivotsupports 55, and

filling bucket tending to tilt it.

It should also be noted that the receptacle 42 is so constructed and so positioned with respect to the inlet 35, that either bucket in extreme position vof said receptacle will be disposeddirectly below said inlet in filling position, with its bottom wall inclined upwardly from the frame bar 48, while the other bucket is in dumping position with its bottom wall Bi inclined downwardly. v V In the operation of the vaporizing deviceli,

assuming that the receptacle 42 is in tilted posi-' tion shown in Fig. 3, the bucket 45 will be in filling position with respect to theinlet 25. Since 2 theauxiliary condenser 29 is operated in the low temperature section of the evaporator unit It and is operated at a lower temperature than themain condenser 22, the liquid collected in thereceiver 21 from said main condenser will evap crate and condense in saidauxiliary condenser 29, and the resultant condensate will flow by gravity into thevessel 24 through theinlet 25 to fill the bucket 45. When the weight of the liquid in the bucket 45 is sutllcient to gravitationally 4 over balance the spring tension of the toggle yieldably holding the receptacle 42 in the position shown, said receptacle will rotate clockwise about itspivotal supports 55 until theleft hand stop 61 reaches the top wall of thevessel 34. In this position of the receptacle 42, the bucket 45 will dump its contents into contact with the warmer surfaces of the walls of thevessel 24, and

the dumped refrigerant'will evaporate at a rate faster than the rate of condensation in the auxpressure in the-vessel 34, which is transmitted back into thereceiver 21, and which will push the liquid in said receiver up through the riser conphase through.

when all of the liquiddumped from the bucket 4B hasbeen evaporated from the vaporizingvessel 24, theauxiliary condenser 29 will again start its condensing function, and will thereby cause the pressure in thereceiver 21 to drop, and theliquid condensate valve 28 and to flow again from the main" concerned, in place of thespring snap arrangement shown, the receptacle 42 may be weighted as for instance at the upper end of the partition plate 42, or if desired a combination of spring 5 snap device or counter-weight may be used. Also,

instead of using a'double, alternately operating bucket arrangement as described, as faras certain aspects of the invention are concerned, a single bucket may be provided which is autol0 matically returned in position by some spring or thereby creates a gravitational leverage on the counter-weight device after said bucket has been tilted into dumping position.

Although certain novel features of the invention have been shown and described and are 1:; pointed out in the annexed claims, it will be understood that various omissions. substitutions and changes inthe several steps of the method and v in its-operation and in the form and details of the apparatus illustrated may be made by those 20 skilled in the' art without departing from the 30 said latter station, vaporizing a portion'of the liquid in said receiver and condensing the vaporiz ed liquid, delivering the condensed liquid from this last mentioned operation into a vaporizing vessel to create liquid lifting vapor pressure 5 therein, and transmitting this vapor pressure to the receiver to force the liquid therefrom into said first mentioned station.

2. A heat transfer circuit including an evaporator, a condenser at a level below that of said 40 evaporator and connected to receiver vapor from said evaporator, and a vessel connected to receive liquid from said condenser and deliver liquid to said evaporator respectively upon decrease and increase of pressure in said vessel, and means to cause said pressure, changes including a second iliarycondenser 29., This will create a vapor condenser connected to receive vapor,from said circuit, a heater communicating with said vessel, andmeans for intermittently delivering liquid from said second condenser to said heater.

3. 'A heat transfer circuit including an evaporator, a condenser at a level below that of. said 1 evaporator and connected to receive vapor from said evaporator, anda vessel connected to receive liquid from said condenser and deliver liquid to said evaporator respectively upon decrease and increase of pressurein said vessel, and means to cause said pressure changes including a second condenser connected to receive vapor from said circuit, a heater communicating with said I thereceiver 21 and thesecondary evaporator unit 20, if desired, to. function in case the pressureoff.

vessel, and means including a tilt-type bucket for collecting liquid from said second condenser and intermittently delivering collected liquid to said heater.

4. A heat transfer circuit including anevapthe formed m oratona condenser below said evaporator and the vaporizingchamber 24 is not'suiflcient toblow out all the liquid fromv thereceiver 21 in one operation. of the dumping 1 bucket.

When theunit 22 starts to function again as a condenser, the condensate from said unit will start flowing into thebucket 44, which has been raised into filling position by the, previous dumping operationof the bucket 45,- so -that the operation previously described is repeated.

connected to receive vapor therefrom, and a yessel connected to receive liquid from' said condenser and deliver the liquid to said evaporator respectively upon decrease and increase of preswhich is smaller than said first condenser and connected to receive vapor from said circuit, a

As far as certain aspects of the invention are 7s heater' communicating with said vessel, and

means for intermittently delivering liquid from said smaller condenser to said heater.

5. A heat transfer circuit including an evaporator, a condenser at a level below that of said evaporator and connected to receive vapor from said evaporator, a vessel connected to receive liquid from said condenser and deliver the liquid to said evaporator respectively upon decrease and increase of pressure in said vessel, and means to cause said pressure changes including a second condenser connected to receive vapor from said vessel, a heater communicating with said vessel, and means for intermittently delivering liquid from said second condenser to said heater.

6. A heat transfer circuit including an evaporator, a condenser at a level below that of said evaporator and connected to receive vapor from said evaporator, a vessel connected to receive liquid from said condenser and deliver the liquid to said evaporator respectively upon decrease and increase of pressure in said vessel, and means including .a tilt-type bucket for collecting liquid from said second condenser and intermittently delivering collected liquid to said heater.,

7. A heat transfer circuit'includingan evaporator, a condenser below said evaporator and connected to receive the vaporfrom said evaporator, a vessel connected toreceive liquid from said condenser and deliver liquid to said evaporator respectively upon decrease and increase of pressure in said vessel, and means to cause said pressure changes including a second condenser smaller than said first condenser and connected to receive vapor from said vessel, a heater communicating with said vessel, means for intermittently delivering liquid from said second condenser to said heater, and means to receive. heat from said condensers operative to cool said second condenser to a lower temperature than said first condenser.

8. A heat transfer circuit including an evaporator, a condenser below said evaporator and connected to receive vapor therefrom, a ,vessel connected to receive liquid from said condenser and deliver liquid to said evaporator respectively upon decrease and increase of pressure in said vessel, and means to cause said pressure changes including a second condenser smaller than said first condenser and connected to receive vapor from said vessel, a heater communicating with said vessel through said second condenser, means including a tilt-type bucket for collecting liquid from said second condenser and intermittently delivering collected liquid to said heater, and refrigerating apparatus for taking heat from said condensers and operative to cool said smaller condenser to a lower temperature than said first condenser.

9. A method of transferring heat which includes producing a cooling efiect by evaporating liquid at a first elevation, conducting'the resulting vapor to a lower elevation and there condensing the vapor to liquid, segregating a portion of the condensed liquid by distillation, and vaporizing said portion to produce pressure .for raising another portion upward to said evaporator.

ROBERT s. TAYLOR.

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