US1896324A - Refrigeration - Google Patents

Description

Feb. 7, 1933. Q MUNTERS 1,896,324

REFRIGERATION Filed June 15, 1928 5 Sheets-Sheet 1 Feb. 7, R933. C G MUNTERS 1,89%,324

REFRIGERATION Filed June 15, 1928 5 Sheets-Sheet 2 I 1 a 1 m Ix, & I

Z Zg.. W IN ENTOR Feb. 7, 1933.. Q & UN E S 1,896,324

REFRIGERATION Filed June 13, 1928 5 Sheets-Sheet 3 Feb. 7, 1933. c. a. MuNTE-Rs 1,896,324

' REFRIGERATION Filed June 13, 1928 5 Sheeis-Sheet 5 'l ENT atentecl Feb. 7, 1933 UNITED STATES PATENT OFFICE CARL GEORG MUNTERS, STOCKHOLM, SWEDEN, ASSIGNOR TO ELECTROLUX SERVEL CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE REFRIGERATION Application filed June 13,

The object of my invention is to improve the functioning of the apparatus shown and described in my co ending application Serial No. 248,244, filed anuary 20, 1928. My invention will be understood from the following description taken in conjunction with the accompanying drawings on which: Fig. 1 is a rear elevational view, partially in cross-section, of a preferred embodiment of my invention installed in a suitable cabinet, the back of which has been removed;

Fig. 2 is an elevational view, partially in cross-section, of the apparatus only, and is taken at right angles to Fig. 1;

, Fig. 3 is an elevational view of the front of the'cabinet, with doors removed, showing the arrangement of the apparatus in the cabinet;

Fig. 4 is a more or less diagrammatic view, partially in cross-section, of an apparatus 90 embodying my invention; 1

Fig. 5 is an elevational view of the lower portion of the apparatus, showing a modified form ofabsorber;

Fig. 6 is an elevational View of the apparatus shown in Fig. 5 and taken at right angles thereto;

Fig. 7 is a front elevational view of a preferred form of evaporator unit; and

Fig. 8 is a view, partially in cross-section,

taken on the line 88 of Fig. 7.

Referring more particularly to Figs. 1, 2 and 4, reference character 10 designates a generator. Generator 10 is placed in a substantially horizontal position and comprises an outer cylindrical shell 11 through which extends a flue 12. Any suitable heating means may be placed in flue 12, such as'a gas burner or electric heating element 13. A

. conduit 14, appropriately termed a riser conduit, communicates with the lower part of generator 10 and extends in a generally upwardly direction to within the upper portion of a receiver or riser vessel 15. A conduit 16, having a small bore in comparison to conduit 14, extends from a point within generator 10 some distance from the top thereof to communicate with conduit 14 at a somewhat higher point. Conduit 16 is U-shaped in order to provide a liquid seal or trap- It will be seen that conduit 16 is connected to 1928. Serial No. 285,046.

the generator at a level higher than that at which riser conduit 14 is connected to the generator.

A conduit 17 communicates with the upper part of vessel 15 and extends upwardly therefrom. Conduit 17 is provided with a series of bafiies 18 in which are formed apertures 19. Adjacent bafiles are preferably so positioned that apertures 19 are in staggered relation to each other. A conduit 20 connects the upper portion of vessel 15 with conduit 17 at a point above bafiles 18. The upper portion of conduit 17 is enclosed within a jacket 21, the ends of which are secured, by welding or otherwise, to the conduit. The interior of that portion of conduit 17 which is within jacket 21, is provided with a series of battles 22, which may be similar to baflles 18. The conduit 17 in combination with jacket 21 and bafiles 22 forms a rectifier or reheat-separator, designated generally by the numeral 7.

Atcondenser conduit 23 communicates with. the upper end of conduit 17 and extends in a generally downwardly direction. Conduit 23, throughout the greater part of its length, is in heat exchange relation with cooling water conduit 24. The lower end of conduit 23 communicates with the lower portion of a vessel 25. A conduit 26 communicates with the bottom of vessel 25, extends downwardly and thence upwardly in a .U-shaped form and passes within a conduit 27 and finally communicates with the upper part of an evaporator 28. A conduit 8 connects the upper part of acket 21 with one of the intermediate turns of condenser conduit 23 while a conduit 9 connects the lower part of jacket 21 with conduit 26 at a point some distance below vessel 25.

Evaporator 28 comprises a cylindrical member placed in a substantially horizontal position. The interior ofthe evaporator is divided into an upper and a lower chamber by a horizontal partitioning member 29. 95 Partition 29 does not extend the entire length of the evaporator and hence the upper and lower chambers are in communication at one end. Partition 29 is provided with a number of lateral ridges 30 which serve to retain 100 shallow pools of liquid thereon. As shown particularly in Fig. 8, the exterior of evaporator 28 is provided with a plurality of fins 31 in order to increase its effective heat absorbing surface. Recesses 32 are formed transversely through a portion of the fins and serve to accommodate ice-freezing trays 33. The evaporator fins are made of flat plates which are cut and punched so that when placed together they form a central evaporator space and separate enclosed spaces for the ice trays.

Conduit 27 connects the'upper chamber of evaporator 28 with a space '34 formed in a vertically disposed heat exchanger 35. Heat exchanger 35 comprises an outer cylindrical shell 36 fitted at both ends with cap- like members 37 and 38. Within shell 36 are positioned a plurality of tubes 39, the ends of which are so flared and welded as to effect closures at both ends of space 34, except at the bottom where a limited communication is established between space 34 and the interior of cap 38 by means of a conduit 47. Space 34 may now be defined as the space within shell 36 between the end closures formed by the flared tubes 39, and exterior to these tubes. Tubes 39 establish communication between cap members 37 and 38. A conduit 40 connects the lower part of space 34 with the upper part of an absorber 41.

Absorber 41 comprises a cylindrical shell placed in a substantially horizontal position and divided into an upper and lower chamber by a horizontal partition 42, which may be similar to partition 29 in evaporator 28, and is provided with ridges 43. As partition 42 does not extend the entire length of the absorber these upper and lower chambers are in communication at the end opposite the point of communication of conduit 40 with the absorber. A cooling water conduit 44, preferably in the form of a square pipe in order to obtain a large contact surface for heat transfer, is wound spirally around the absorber and preferably welded thereto. The discharge end of conduit 44 is connected to the inlet of conduit 24 so that the cooling water passes through the two conduits in series.

A conduit 45 connects the upper portion of the lower chamber of absorber 41 with the interior of cap member 38. The lower end of conduit 47 is below the lowermost point of conduit 45. A conduit 46 connects the interior of cap member 37 with the lower part of the lower chamber in evaporator 28. A conduit 48 connects the upper part of vessel 25 with the lower part of absorber 41.

A conduit 49 connects the lower part of absorber 41 with one end of another conduit 50, which comprises the outer member of a concentric-pipe heat exchanger, designated generally by reference character 51. The conduits comprising heat exchanger 51 extend substantially vertically downward from the point where conduits 49 and 50 are joined, and thence upwardly in the form of a coil. A conduit 52 communicates with conduit 50 and extends within generator 10 where it opens upwardly atthe same level at which conduit 16 opens downwardly.

A conduit 53 communicates with the bottom of riser vessel 15 and extends within conduit 50, thus forming the inner conduit of heat exchanger 51. The other end of conduit 53 communicates with a charging plug 54 which is connected to the upper chamber of absorber 41 by a conduit 55.

In order to obtain maximum efiiciency it is desirable to thermally insulate generato 10, heat exchanger 51 and a portion of riser conduit 14. This is preferably accomplished by enclosing these members in a metal container 56 which is packed with a-suitable insulating material.

The preferred arrangement of the apparatus in a cabinet 57 is shown in Figs. 1 and 3. Cabinet 57 comprises a lower apparatus compartment 58 and an upper refrigerating compartment 59. There is also a shallow apparatus compartment 60 which occupies substantially the entire rear of the cabinet. Within the lower apparatus compartment is housed the generator 10 and heat exchanger 51 within the metal container 56, and the absorber 41. Heat exchanger 35, riser conduit 14, riser vessel 15, rectifier 7, condenser 23 and other connecting conduits occupy the shallow apparatus space 60. Evaporator 28 projects through the rear wall of upper refrigerating space 59 and substantially the entire evaporator and its attendant radiating fins 31 are within space 59.

The gas heat exchanger 35 and riser conduit 14, vessel 15 and conduit 17 are preferably constructed of suflieient strength to support the weight of the upper members, ineluding condenser 23 and evaporator 28.

After the apparatus has been placed in the.

cabinet the space remaining in shallow compartment 60 is packed with a suitable heat insulating material such as, for instance, corkboard.

The operation of the apparatus in accordance with this preferred form of my invention is substantially as follows:

Assume that the lower parts of the apparatus are filled with liquid, for instance Water with ammonia dissolved therein, which stands at the levels indicated in the absorber 41 and conduit 14. The communication between the generator 10 and conduit 14 through conduit 16 is thereby shut off. Ammonia expelled in the generator due to application of heat thereto consequently cannot escape but collects in the upper part of the generator. The condensation of ammonia vapor previously supplied to the condenser 23 will thereby continue and as the communication between condenser 23 and evaporator 28 is shut off by the liquid seal in the U-shaped conduit 26, the pressure in the condenser will decrease and consequently the liquid in conduit 14 is forced upwardly into riser vessel 15 until the liquid level in the generator has fallen below the lowermost portion of the bent portion of conduit 16. When this is the case. the liquid is forced out of conduit 16 and the gas expelled in the generator will escape therethrough and through conduit 14 to the condenser. At the same time the liquid in conduit 14 will flow by gravity back into the generator which is thereby refilled the communication through conduit 16 is again shut off and a new period starts. The liquid drawn up into vessel 15 will flow by gravity through conduits 53 and 55 to the absorber 41. The ammonia vapor expelled and led to the condenser flows upwardly through conduit 17, within 'which any water vapor which accompanies the ammonia is liquefied and separated as it passes baffles 18 and particularly bafiies 28 which comprise a part of rectifier 7. This rectification will be more fully described later in the specification.

When the apparatus is first started the above described operation takes place as soon .as a sufiicient amount of vapor has been expelled and again condensed to fill the liquid seal in U-shaped conduit 26. As conduit 26 is filled to a point above the level of conduit 9, liquid ammonia passes therethrough to jacket 21. The liquid ammonia in jacket 21 is at a temperature but slightly below the boiling point of ammonia at the existant pressure and therefore cools the vapors within conduit 17 sufficiently to cause the lique' faction of the water vapor but not ofthe ammonia vapor. The vaporous ammonia formed in jacket 21, due to the absorption of heat from the vapors within conduit 17, passes therefrom through conduit 8 to condenser conduit 23, where it is recondensed.

In the evaporator the liquid ammonia is distributed over partition 29- and comes in intimate contact with a gas inert with respect to ammonia, for instance hydrogen. The mutual diffusion of the ammonia and hydrogen is attended by a low value of the partial pressures of both gases and the liquid ammonia present evaporates and the accom-v panying reduction of temperature produces refrigeration.

The gaseousmixture of ammonia and hydrogen thus formed in the evaporator has a greater specific weight than relatively pure hydrogen and hence passes from the upper chamber, around the end of partition 29 to the lower chamber of evaporator 28 from where it passes through conduit 46, heat exchanger 35 and conduit 45 to the lower chamber of absorber 41.

In the absorber the gaseous mixture is brought in intimate contact with water containing but relatively little ammonia in solution, commonly termed weak liquor. The ammonia gas is absorbed and the relatively light hydrogen passes from the lower to the upper chamber in the absorber and thence through conduit 40, space 34 in heat exchanger 35 and conduit 27 to the upper chamber of evaporator 28. The heat resulting from the absorption of the ammonia gas by the water is carried away by the cooling water in conduit 44.

A somewhat modified embodiment of my invention is shown in Figs. 5 and 6, wherein the horizontal cylindrical absorber 41 just described is replaced by a tubular absorber coil 61. One end of coil 61 communicates with cap member 38, whilst the other end communicates with space 34 in heat exchanger 35. A receiving vessel 62is placed below the lowermost turn of coil 61 and connected therewith by means of a conduit 63. Conduit 49 communicates with the lower part of vessel 62 while conduit 55 communicates with the uppermost turn of coil 61. Cooling water conduit 44 is wound concentric with coil 61 and is brought in good heat transfer relation therewith b means of welding, soldering or the like. onduit 48 connects vessel 25 with receiving vessel 62.

The operation of this form of the invention is similar to that previously described. The gaseous mixture of. ammonia and hydrogen passes from cap member 38 of heat exchanger 35 into the uppermost turn of absorber coil liquor from generator 10 like- 61. The wea wise enters the upper part of coil 61 through conduit 55. The ases and 1i uid pass downwardly through t e coil, during which passage the ammonia gas is absorbed. The strong liquor thus formed passes from coil 61 through conduit 63 to receiving vessel 62 and thence through conduits 49, 50 and 52 to generator 10. The heat develo ed by the absorption of the ammonia by t e water is carried away by the cooling water in conduit 44. The hydrogen gas passes from the lowermost turn of coil 61 upwardly into space'34 in heat exchanger 35 and thence through conduit 27 to evaporator 28.

While I have shown and described two more or less specific embodiments of my invention, it is to be clearly understood that they are by way of illustration only, and I am not limited thereby except inview of the appended claims taken in connection with the prlor art.

What I claim is:

1. In refrigerating apparatus, an absorber an expeller and means for producing flow 0 liquid therebetween including a riser conduit communicating with the expeller at a first level and extending upwardly above the expeller, and a tubular flow control member communicating with the expeller below the top thereof at a second level higher than said first level and communicating with said riser conduit at a third level above said second level and said tubular member having an intermediate portion below said second level. 2. In refrigerating apparatus, a heated vessel, a cooled vessel and means for producing flow of liuqid therebetween in periodic cycles including a riser conduit communicating 1 with the heated vessel at a first level and extending upwardly above the heated vessel, and a cycle control conduit member communicating with the heated vessel below the top thereof at a secondlevel higher than said first level and communicating with said riser conduit and said cycle control member having a portion below said second level.

In testimony whereof I have afiixed my signature.

20 CARL GEORG MUNTERS.

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