US2350347A

US2350347A - Refrigerating apparatus

Info

Publication number: US2350347A
Application number: US395944A
Authority: US
Inventors: Richard S Gaugler
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1941-05-31
Filing date: 1941-05-31
Publication date: 1944-06-06
Anticipated expiration: 1961-06-06

Description

June 6, 1944. R. S. GAUGLER 2,350,347 REFRIGERATING APPARATUS Filed May 31. 1941 n 5 sheets-sheet 1 u2 94 @C 'as `lune 6, 1944. R, s, GAUGL|5R 2,350,347" REFRIGERATING APPARATUS Filed May 31, 1941 5 sheets-sheet 2 I Y fos 1' @im V f 11' June 6, 1944. R, s GAUGLER 2,350,347

REFRIGERATING APPARATUS Filed May' 51, 1941 5 sheets-sheet 3 MMLWEIZV June 6, 1944- R. s. GAUGLER REFRIGERATINGYAPPARATUS Filed May 31, 1941 5 sheetssheet 4 June 6', 1944. RQ s GAUGLER 2,350,347

REFRIGERATING APPARATUS Filed May 3l, 1941 5 Sheets-Sheet 5 74 y INVENToR.

MPM l a Patented June 6, 1944 2,350,347 REFRIGERA'I'ING APPARATUS Richard S. Gaugler, Dayton, Ohio, assignmto General Motors Corporation, corporation of Delaware Dayton, Ohio, a

Application May 31, 1941, Serial No. 395,944

14 Claims.

This invention relates to refrigerating apparatus and more particularly to household absorption refrigerating machines.

The cooling elements of, household absorption refrigerating machines have been somewhat -complicated and costly. It is an object of my invention to provide a cooling unit of improved construction which is more simple and less expensive than prior cooling units.

It is another object of my invention to provide an improved yhigh humidity compartment in household absorption machines.

It is another object of my invention to provide an economical eficient arrangement of primary and secondary cooling units in an absorption system.

In absorption machines, it has ben customary to place a screen or screens within the passages of the evaporator and other means in the absorber in order to increase the amount of liquid surface exposed to the gas and vapor. 'I'he liquid by capillary action spreads over the surface of the screens. I nd that there is poor heat transfer between the walls of the passages and the screens so that the eiciency of evaporation is reduced.

It is an object of my invention to provide a capillary means forming an integral part of the wall surface of the passages of .the absorber and/or the evaporator by which liquid collected in the bottom of the passages is spread by a. capillary action over the entire wall surface of the passages.

In the past, in absorption machines the condenser has been located in the upper Dart of a ue at the back of the cabinet which at its lower end received waste heat from the absorber and generator as well as the products of combustion of the gas burner used to-heat the generator. In such an arrangement. the air rising in the flue for cooling the condenser was already warm so that the condenser was not contacted and cooled by air at room temperature.

It is an object of my invention to provide a cooling arrangement for refrigerating systems wherein air at room temperature is used for cooling the condenser.

It is an other object of my invention to provide an improved condenser for absorption systems in which condensation is assured under varying temperature conditions.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings, wherein a preferred form of lthe present invention is clearly shown.

Fig. 4 is a sectional view of the cooling unit taken along the line 4 4 of Fig. 3;

Fig. 5 is a view in side ,elevation of the cooling unit;

Fig. 6 is a sectional view taken along the line 6 6 of Fig. 3;

Fig. 7 is a view taken along the line 1 1 of Fig. 3; Fig. 8 is a sectional 3 8 of Fig. 3;

Fig. 9 is a sectional view taken along the line 9 9 of Fig.3; i

Fig. 10 is an enlarged longitudinal sectional view of the tubing shown in Figs. 3 to 5;

Fig. 11 is an enlarged transverse sectional view of the same tube;

Fig. 12 is a sectional |2 l2 ofFig. 3;

Fig. 13 is a sectional view smaller but in other Ways corresponding to the sectional view shown in Fig. 11 of a modified form of capillary surface in the tubing of the cooling unit and/or absorber.

Fig. 14 is a diagrammatic view of the absorption refrigerating system;

Fig. 15 is a fragmentary enlarged section through the rear wall of the cabinet taken substantially on the line |5 |5 of Figs. 3 and 4; and

Fig. 16 is a rear view of the inner liner member with the secondary refrigerant circuit wrapped around it.

Briefly, I have shown an absorption refrigerator characterized by a flat cooling unit formed of tubingshaped in serpentine fashion to which is bonded a metal plate for receiving ice trays. The portion of the refrigerator containing the cooling element is separated from the lower portion by a transparent plate of poor heat conductivity. This lower compartment, formed by the glass plate, is cooled by a secondary refrigerant circuit surrounding the compartment which is connected to the secondary condenser which in turn is clamped to the gas outlet portion of the view taken along the line view taken along the line cooling unit. The interior of the tubing used to make the evaporator is provided with a capillary means so designed as to accomplish intimate thermal contact between the surface of the liquid liner member Ythe tube 31 into the refrigerant where refrigeration is produced and the walls of the tubing. For example, the interior of the cooling unit may be provided with helical grooves which are square in cross-section as shown in Fig. 10. These grooves have their parallel walls sumciently close together that they form a capillary cavity so that liquid will be drawn by capillary attraction from the bottom of the tube all the way around each of the grooves. In modified form, this capillary surface is provided by providing sintered metal upon the interior wall of the tube. This sintered metal is porous and its pores are capillary size so that hquid is distributed throughout the surface of the sintered metal, as in the case of the grooves. 1 A diagonal partition separates the air flowing from the generator and absorber of the back of the cabinet from the air flowing from the condenser. The condenser is of a peculiar construction in which the vapor inlet and the gas outlet are connectcd to inclined condensing passages which in turn connect at their lower ends to a common .liquid receiver.

Referring now to the drawings and more particularly to Fig. 1, there is shown an insulated' refrigerator cabinet generally designated by the reference character 20 and provided with inner 22 surrounded by linsulation 24. A cabinet door 24 closes the food compartment. The food compartment is divided into an upper freezing compartment 28 and a lower high humidity compartment 30 by a dividing shelf l2 preferably formed of a sheet of transparent material which may be sealed to the walls of the compartment. If desired a seal may also be provided between the front edge of the shelf and the rear face of the door 26Aso as to substantially completely seal the compartments from each other.

The upper compartment 28 contains a primary evaporator 34. This primary evaporator 34 is primarily formed of tubing bent into a serpentine shape, as shown in Fig. 3. In addition to being formed into a serpentine shape as shown in Fig. 3, this tubing is also flattened in varying amounts which decrease uniformly from the front edge to the rear edge of the evaporator as is illustrated by the sections shown in Figs. 6 to 8 inclusive. In addition, the portion of the tubing designated by the reference character 36 is provided with a sloping wedge 38 which is U-shaped in cross-section and has its largest end adjacent the rear of the evaporator so as to provide a thermal connection between this portion of the tubing and the metal plate 40 which forms the top surface of the evaporator. This metal plate 40 `is bonded metallically directly to the evaporator tubing as shown in Figs. '7 and 8 and through the wedge 38 as shown in Fig. 9. With this attening of the tubing and the use of the wedge 38 the portion of the tube beneath the plate 40 has a uniform downward slope to the end 42 which serves as the inert gas inlet of the evaporator tubing.

Any unevaporated liquid collecting in the end 42 of the evaporator tubing may be drained by gas tube 92 which carries it to the absorber receiver.

The evaporator 34 is supported at one end from the back plate 124 by a set of U-shaped brackets. Cine of these U-shaped brackets |26 is fastened to the back plate |24 while the other bracket 35 is welded to the portion 44 of the evaporator tubing in the insulation space. These brackets are connected together by a 13011739.

The other end of the evaporator 34 is supported by the connections of the ends of its tubing with the gas interchanger which is fastened to the back;plate l|24.

The end 44 which serves as the liquid refrigerant inlet and the inert gas outlet of the evaporator tubing is located within the insulation space and is provided with a connecting plate 46 to which is clamped a secondary plate 44 by means of the screws l and 52. A cover 2l closes the opening in the back of the inner liner 22 which opening provides access to the insulation space where the end 44 of the evaporator 34 and the plates 46 and 45 are located. Bonded to this secondary plate 4B is the condenser portion 54 of the secondary refrigerant circuit. This condenser portion 54 slopes downwardly parallel to the portion 44 of the evaporator tubing to which it is clamped.

Prior to forming the tubing into the serpentine shape the evaporator tubing is threaded on the inside by a tool which forms the capillary grooves 55 (see Figs. 10 to l2). These capillary grooves 58 have square bottoms and parallel sides which are sufliciently close together to cause any liquid in the tube to be drawn into the grooves by capillary attraction. This capillary attraction will cause liquid to spread throughout the grooves in the tubes so that when hydrogen and liquid ow through the tubing .amount of liquid surface with the inert hydrogen.

there will be a large provided for contact Th'is improves the eficiency of evaporation since the configuration which provides capillary action within the tube is an intimate part of the metal wall of the tube so that there is the maximum heat transfer between the outer walls of the tube and the liquid held in capillary attraction.

In Fig. 13 there is shown another way in which the capillary surface may be in intimate thermal contact with the walls of the tubing. In Fig. 13 the capillary surface is formed by a layer of sintered metal 58, such as sintered iron. which is bonded to the interior of the tube by applying the powder prior to sintering to the interior walls of the tube, after which the powder,l which has been applied to the walls of the tube, is sintered by placing the tubing in a non-oxidizing atmosphere for .asufilcient length of time at a sufficiently high temperature. For example, the sintering may be carried out at temperatures around 2000 F. for periods from l5 minutes to an hour. Preferably the tubing is formed of steel and a sintered material is formed from powdered iron which includes some ferrous powder. For the sintered wall coating, I prefer to use theprocess and materials described in the Lenel Paten't No. 2,226,520, dated Dec. 24, 1940. However., other processes and materials may be used if desired. For example, the metal particles may be bonded to the wall of the tubing and to each .other by another metal or other material such as tin or solder. This inner coating of sintered .material provides a capillary layer which will distribute any liquid in the bottom of the tube throughout the inner wall surface of the tube until the pores of the sintered metal are saturated. The metal plate 40 may also be made of iron or steel and may be bonded to the tubing by copper hydrogen brazing, welding, soldering or other suitable means. If the copper-hydrogen brazing process is used this could be performed at the same time when the sintering is performed. The secondary condenser 54 drains into the secondary evaporator 60 which is provided with .The upper end of the analyzer I|2 highest point of the weak liquor conduit sure equalizing tube |08 ascesa? serpentine loops extending over the outside of the bottom, back, and side walls of the lower compartment 30. Since theinert gas outlet portion 44 of the cooling unit is at a much higher temperature than other portions thereof the secondary evaporator will be maintained at a comparatively high refrigerating temperature so that a relatively high humidity will be maintained in the lower compartment 30. The temperature of the walls of the lower compartment 30 and the secondary evaporator is suiliciently low to provide adequate refrigeration. v

The evaporator 34 is supplied with liquid ref gerant from a novel form of condenser 0l. This condenser 34 is 'mounted upon the upper portion of the rear wall oi' the cabinet and is provided with an inlet header 00 which connects to a plurality oi' parallel tubes 10 which slope downwardly at an angle and terminate in a liquid receiver 60 at the lowest portion ofthe condenser.

the liquid receiver 60 are a plurality of parallel tubes 12 which extend upwardly to a point ad- `iacent inlet header 66, after which they curl downwardly and terminate in a gas header 14. Transverse tins 16 are distributed uniformly over both groups of tubes. Ii' desired, these lns may be divided to provide a sep'arate section for each bank of parallel tubes. 'I'he liquid receiver 68 is connected by a liquid tube to the refrigerant inlet and inert gas outlet portion M of the evaporator tubing. The inlet header 66 is connected by tubing 80 which extends downwardly to the generator structure. I'he gas outlet header 14 ls connected by tubing 34 to a hydrogen tube 86 which connects to the gas interchanger 88 which in turn connects to the

tubes

90 and 92. 'I'he lower end of the tube 92 connects to the top of the absorber receiver while the lower end of the tube 30 connects to the upper end of the l' absorber 34.

Beneath the insulated portion of the cabinet there is a generator |0| provided with a standpipe |03 and a vapor lift pump |05 which discharges through a tion of the standpipe |03. The vapor discharged from the' vapor lift tube through the first part of the pressure tube |03 to the connecting tube 0 which discharges its vapor beneath the liquid level in the lower end of the slightly inclined analyzer I I2. is provided with a standpipe ||4 containing bailles forming a rectifier. This standpipe IH is connected to equalizing the vapor conduit 00 which in turn connects to the condenser inlet 66. 'I'he lower end of the pressure equalizing tube '|08 connects to the |02 extending from the generator |0| to the top of the absorber 94 to prevent gas or vapor from collecting in this conduit. The lower end of the prescontains a column of at the same level as stand pipe |03. This pressure equalizing weak liquor substantially the level of liquid in the seals the lower end of the tube |08. The liquid from the generator passes through the liquid conduit |02 which extends through the slightly inclined analyzer 2 and discharges the liquid from the generator through the exposed portion I|3 into the lower end of the pressure equalizing tube |00. 'I'he lower end of the pressure equalizing tube |08 connects to and discharges the liquid into a tube |51 which extends through the liquid heat interchanger |01 and connects to a precooler |09 which in turn Extending upwardly at an angle fromA tube |00 into the upper por- |06 iiowsv discharges into the upper end of the absorber 9i. 'I'he absorber 04 preferably is provided with capillary grooves in its vinner wall surface such as the grooves 50 shown in'Fig. 11 for the purpose oi' spreading by capillary action the weak absorption liquid t oughout the inner wall surface of the absorber. Instead of the capillary grooving, the sintered metal layer may be bonded to the lnner'walls of the absorber as shown in Fig. 13. The absorber 34 is provided with a receiver at its outlet which in turn is connected through the connection |6| to the liquid interchanger |01. The outer portion of .the liquid interchanger |01 connects through the iiq.- uid conduit |50 with the upper portion of the slightly inclined analyzer ||2. The lower end of the analyzer ||2 is connected duit 99 to the rear portion of the generator to supply the generator with rich liquor.

Upon the back of the cabinet there is provided a ilue formed of the extensions ||3 and ||5 of-the side walls of the cabinet and the rear covers ||1 and ||9 which tormthe back wall of,

the llue. 'Ihe flue is divided into two parts by a diagonal metal dividing wall |2| which extends from the left end of the absorber to the right end of the condenser as shown in Fig. 2. This then provides a iiue |23 between the dividing wall |2| and the extension ||5 and a second flue |25 between thedividing wall I 2| and the extension ||3. Vertical metal walls |21 and |20 are provided at opposite ends of the absorber. Louvers |3| are provided in the upper portion of the extension ||5 while louvers |33 are provided in the lower portion of the extension |I3.

By this arrangement all of the waste heat and products of combustion oi' the absorber and the generator pass upwardly through the ilue |23 and are discharged through the louvers 3| without contacting the condenser 64. This pro- .vides a nue of ample proportions for creating .a

natural draft for cooling both the absorber and the generator. Provision of a condenser in such a flue would not add to the circulation through the ue. By locating the condenser 6I in a separate due |25, the air at room temperature contactsI the condenser 64 without being warmed by any other elements of the system. Thus the condenser, excepting for diiferential due to heat transfer, may be maintained at room tempera'- ture. This arrangement greatly increases the eiiciency of the system. o

My improved form of condenser also increases the efficiency since the warm vapor from the analyzer flrst'passes through` theupper bank of tubes of the condenser and normally substantially all the vapor is condensed in this upper bank of tubes and is collected in the liquid receiver and is thence conducted through the liquid tube 10 to the primary evaporator. ever, if the vapors should not be suiiciently cooled to be liqueiied in the upper pass, when they reach the receiver 6B they will ascend the lower pass 12 where they will befurther cooled and then will continue to ascend until they are liqueed after which they will ow downwardly in lquid form through the lower pass to the liquid receiver 68.

In the absorber 94, the cooled weak liquor flows downwardly and removes ammonia from the mixture of ammonia and inert hydrogen gas which flows upwardly through the absorber 94. Theinert gas arrives at the upper end of the absorber substantially free of ammonia. This inert gas then rises through the tube to the by the, liquid con- Howgas interchanger 8B where it is further cooled and then enters the lower portion 36 of the In the evaporator tubing, the

inert gas will continue upwardly through theevaporator tube while the liquid refrigerant ows downwardly therein. The amount of refrigerant in the inert gas will increase as the inert gas ows upwardly through the evaporator tubing. This will cause the evaporating temperature to -rise since the partia1 pressure of the refrigerant in the hydrogen will increase as it flows toward the upper end of the evaporator tubing. Since the greater portion of the evaporator tubing is bonded thermally'to the metal plate 40 it will be malntained at somewhat the same temperature.

However, the nal portion of the evaporator tubing which is located in the insulation space, is not bonded thermally to the plate 40, so that this portion will reach a higher temperature. Also, the secondary circuit will supply heat at a higher temperature level than is supplied in the compartment 28 so that the temperature of that portion within the insulation space will be maintained at a higher temperaturelevel. Refrigeration performed at this temperature level could not be used for freezingfpurposes or for cooling the compartment 28. However, refrigeration at this temperature level serves very desirably in providing refrigeration of the lower compartment at a high temperature through the large surface, mainly the surface of the liner, so that there is only a small temperature differential between the air in the compartment 30 and the secondary condenser 54 and the upper portion Mv of the evaporator tubing. By this arrangement of cooling the compartment 30 at a higher temperature level and conducting this heat to the outlet portion of the evaporator, additional refrigeration can be accomplished with the inert gas which is already rich in refrigerant vapor. Furthermore by this introducing an additioiial amount of refrigerant vapor into the inert gas, the saturated inert gas is made heavier. This increases the rate of circulation throughout the inert gas circuit which takes place by reason of the difference in gas which has been robbed of refrigerant and inert gas which is saturated with refrigerant. This saturated inert gas leaves the evaporator 3l and passes downwardly through the gas interchanger 88 and the gas tube 92 to the receiver HI located at the bottom of the absorber from which point it flows upwardly through the absorber 94.

While the form of embodiment of the invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms mightbe adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

' l. Absorption refrigeratng apparatus comprising a cabinet, a system for cooling the interior of the cabinet including a cooling unit in heat exchange relation with the interior of the cabinet and a generator, a condenser, and an absorber outside the cabinet, said cabinet being provided with a vertical flue upon its back wall, said generator and absorber being located adjacent the bottom of the flue, said condenser being located adjacent the top of the flue, a dividing member extending diagonally upwardly to densitybetween the inert divide the iiue into two paths of ilow, the one division of the flue being wide at the top and having the condenser located at its upper end, the second division of the ilue being wide at the bottom and having the generator and the absorber located at its lower end.

x 2. Absorption refrigerating prising a cabinet apparatus comhaving an inner liner enclos- Ying a compartment to be cooled. means within the liner for dividing said compartment, insulating means surrounding the inner liner, an ab sorption cooling unit having an inert gas outlet portion located outside said liner within said insulating means and a second portion arranged serially with respect to the initial portion located in one of the divisions of said compartment for receiving refrigerant liquid discharged from said initial portion, generating and absorbing means for supplying refrigerant to said inert gas outlet portion and for circulating a gas inert with respect to said refrigerant through said cooling unit in such a direction that it leaves at the inert gas outlet, avsecondary refrigerant system having an evaporating means mounted in heat exchange relation with the outside of said inner liner and a condensing means-`in heat exchange relation with said inert gas outlet portion.

3. Absorption refrigerating apparatus including an absorption cooling unit in the form of an elongated conduit means having metal walls and having an inert gas inlet at one end and a gas outlet at the other end, the metal walls of said conduit means adjacent the gas inlet being adapted for arrangement in heat exchange relation with a first medium to be cooled, la secondary refrigerating system for maintaining a second medium at a higher temperaturethan the first, said secondary refrigerating system having its condensing portion in heat exchange relation only with the portion of the metal walls adjacent the gas outlet of the cooling unit for increasing the evaporation of refrigerant Ainto the inert gas as it leaves the cooling unit.

4. Absorption refrigerating apparatus including an absorption cooling unit in the form of an elongated conduit means having metal walls and having an inert gas inlet at one end and a gas outlet at the other end, the metal walls of said conduit means adjacent the gas inlet being adapted for arrangement'in heat exchange relation with a rst medium to be cooledand being Aprovided with means for increasing the area of heatexchange relation with said first medium, wall means for separating a portion of the metal walls of said passage adjacent said gas outlet from said first medium to be cooled so as to be out of direct contact with said rst medium, a secondary refrigerating system formaintaining a second medium at a higher temperature than the first, said secondary refrigerating system having its condensing portion in heat exchange relation only with said portion of the metal walls adjacent the gas outlet of the cooling unit for increasing the evaporation of refrigerant into the inert gas as it leaves the cooling unit.

5. A heat transfer device comprising an enliquid upwardly from the surface by capillary action, Said capillary structure having a portion of itssurface exposed in the vapor space saturated with the liquid to expose the volatile liqcontainer means being provided with a porous4 capillary structure extending upwardly from the surface of the volatile liquid for conducting the liquid upwardly fromv the surface by 'capillary action, said capillary structure having a portion of its surface exposed in the vapor space saturated with the liquid to expose .the volatile liquid in the upper portion of the vapor space, said capillary structure being in the form of sintered powdered metal.

7. Absorption refrigerating apparatus including a container. means for supplying liquid refrigerant to the container in an amount insumcient to completely flll the .container to leave a space above the surface of the liquid and also for circulating an inert gas through the container, said container being provided with a porcus capillary structure of sintered metal in contact with the refrigerant liquid and extending upwardly from the liquid surface into contact with said gas, said refrigerant liquid saturating said structure by capillary action to provide an increased area of contact between the refrigerant liquid and the gas.

8. Absorption refrigerating apparatus including a cooling unit, means for supplying sumcient liquid refrigerant to partially fill but insufficient to completely fill the coolingunit and also for circulating an inert gas through said cooling unit, said cooling unit being provided with a porous capillary structure of sintered metal having a portion in contact with the liquid refrigerant and extending upwardly from the liquid surface into contact with said gas, said liquid refrigerant saturating said structure by capillary action to increase the area of contact between the refrigerant liquid and the gas.

9. Absorption refrigerating apparatus including a cooling unit, means for supplying sufficient liquid refrigerant to partially fill but insuiiicient to completely fill the cooling unit and also for circulating an inert gas through said cooling unit, said cooling unit being provided with a porous capillary structure of sintered metal having a portion in contact with the liquid refrigerant and extending upwardly from the liquid surface into contact with said gas, said liquid refrigerant saturating said structure by capillary action to iny crease the area of contact between the refrigerant liquid and the gas, said capillary structure being in the form of a continuous coating upon the interior walls of the cooling unit.

l0. Absorption refrigerating apparatus including an absorber, means for supplying weak liquor in an amount insuiiicient to completely ll the absorber and also for circulating an inert gas charged with refrigerant vaporthrough the absorberfor transferring the vapor to the liquor, said absorber being provided with a porous capillary structure of sintered powdered metal having 'a portion in contact with the weak liquor and` extending upwardly from the liquid surface into contact with said inert gas charged with refrigerant vapor, said weak liquor saturating said structure by capillary action to increase the area of contact between the weak liquor and the gas.

11. Absorption refrigerating apparatus including an absorber, means for supplying weak liquor` in an amount insufficient to completelyll the absorber and also for circulating an inert gas charged with refrigerant vapor through the absorber for transferringthe vapor to the liquor, said absorber being provided with a porous capillary structure of sintered powdered metal having a portion in contact with the weak liquor and extending upwardly from the liquid surface into contact with said inert gas charged with refrigerant vapor, said weak liquor saturating said structure by capillary action to increase the area of contact between the weak liquor and the gas, said capillary structure being in the form of a continuous coating upon the interior walls of the absorber.

12. A heat transfer device comprising an enclosed container means only partially filled with a volatile liquid leaving a space for vapor above the surface of the liquid, the interior of the container means being provided with a structure .having capillary grooves extending upwardly from the surface of the volatile liquid into'the vapor space, said capillary grooves having substantially parallel walls spaced suiiiciently close together that the-volatile liquid will be attracted to all parts of the grooves by capillary action.

13. A heat transfer device comprising an enclosed container means only partially filled with a volatile liquid leaving a space for vapor above the surface of the liquid, the interior walls bordering the vapor space of the container means being of metal and being provided with a capillary surface forming an integral'part of the wall structure of the container means, said capillary surface extending from the surface of the liquid upwardly to carry the liquid through capillary action up over the wall surface bordering the vapor space to keep this wall surface wetted with liquid.

14. A heat transfer device comprising an enclosed container means only partially filled with a volatile liquid leaving a space for vapor above the surface of the liquid, the interior walls of the container means bordering the vapor space being of metal and being provided with a capillary metal coating of porous sintered'iron forming an integral part of the metal wall structure, said capillary surface extending from the surface of the liquid upwardly to carry the liquid through capillary action up over the wall surface border- 'ing the vapor space to keep this wall surface DISCLAIMER 2,350,347.-Rz`chard S. Gaugler, Dayton, Ohio. vREmuGERA'IING APPARATUS. Patent dated June 6, 1944. Disclaimer filed Mar. 17, 1947, by the assignee, General Motors Corporation.

Hereby disclaims the subject matter of claim 12.

[O zc'ial Gazette April 15, 1.947.]

DISCLAIMER 2,350,347 .--Rz'chard S. Gaugler, Dayton, `Ohi. REFRIGERATING APPARATUS. Patent dated June 6, 1944. Disclaimer filed May 9, 1946, by the assignee, General Motors C'orporat'm. A Hereby disclaims the subject matter of claim 13 of said patent.

[Oficial Gazette June 11, 1.946.]