US2067325A - Refrigerating apparatus and method - Google Patents

Description

Jan. 12, 1937. c. L. JONES ET AL 2,067,325

REFRIGERATING APPARATUS AND METHOD Original Filed April 27, 1931 3 Sheets-Sheet l INVENTOR CkarleJL. fonas' Q'owardJ MYlvaz'n ATTORNEY Jan. 12, 1937. NE Er AL 2,067,325

REFRIGERATING APPARATUS AND METHOD Original Filed April 27, 1931 5 Sheets-Sheet 2 W /M "A Zw/ WM/ y M 161 g r MW WW" i INVENTOR Charles L.Jones /g Bjgoward flvmim ATTORNEY Jan. 12, 1937. I c. L. JONES ET AL 2,067,325

REFRIGERATING APPARATUS AND METHOD Original Filed April 27, 1931 s Sheet s-Sheet s 7 #jAw WW @W INVENTOR Ukarhs .5. kfo'rzes Howard A. M 710001 BY J Patented Jan. 12, 1937 UNITED STATES PATENT OFFICE I REFRIGERATING APPARATUS AND METHOD Charles L. Jones, Pelham, N. Y., and Howard S.

Mcllvain, Belleville, N. J., assignors, by mesne assignments, to Adico Development Corporation Original application April 27, 1931, Serial No. 533,036. Divided and this application May 7, 1931, Serial No. 535,784

17 Claims.

Our present invention relates to refrigerating apparatus and methods particularly adapted for use in connection with solid carbon dioxide as the refrigerant. By our invention, we simplify the apparatus and make it readily adaptable for refrigerators of widely varying types and sizes, and for widely varying conditions of use of any refrigerator in' which the invention has been embodied.

1 An important feature is to make the solid car- .bon dioxide and its container respond quickly and effectively for re-chilling the atmosphere of the refrigerator, when suddenly over-heated as by frequent use of side-opening doors of refrigerated delivery trucks, but many of its features may be effectively utilized in other types of refrigerators, as for instance, household, display-case, or storage room refrigerators; also refrigeratoi 'cars and less-than-carload lot containers.

One object of the invention is to-provide a novel container forthe solid carbon dioxide, constructed with a view to collecting heat from a comparatively wide area of the atmosphere of the refrig crated space and preferablyfrom theupper or warmer region of said space; preferably also to collect it rapidly through metal surfaces and to conduct it to the interior of said container through an all metal path. When the exterior surface of the metal is exposed to the atmosphere directly, its response to changes of temperature of the atmosphere is very I rapid as compared with the much slower response of metal containers that absorb heat through heat insulation. The less the exterior insulation and the further the collected heat has to travel through the all metal path, the more closely will the collecting surface tend to follow the tempera ture of the contacting air rather than that of the refrigerant source. Consequently, the quicker and more effective the response will be.

In certain special cases, where low temperature or a high rate of refrigeration is required, the refrigerant container may be used without any insulation either outside or inside, the solid carbon dioxideresting directly on the metal bottom of the container. On the other hand, interior insulation as by wrapping the blocks of solid carbon dioxide in one or many thicknesses of paper or insert'ng one or many thicknesses of paper or of corrugated paperboar-d'between the solid and thebottomof the container may be availed of to slow down the rate of sublimation of the solid,

thereby increasing the effective refrigerant temperature of the walls of the container and its remote collecting surfaces, without proportionally decreasing the sensitiveness with which said surfaces will collect and deliver the heat.

One important factor is that'whatever may be the basic refrigerant evaporation rates thus predetermined, it is seldom possible to avoid formation of frost on the heat collecting surfaces. The lowerthe temperature of these surfaces, the more frost they are likely to collect, and such frost layer is variable and therefore unreliable exterior insulation tending to make the exterior refrigerant surface vary from approximately the freezing point of water when the frost is very thick, down to say 50 or more below zero R, which may be the temperature of the bottom of the container when it is free from frost.

It will be evident that by having metallic heat conducting flanges a-nd fins of large area extending into contact with relatively remote parts of the atmosphere of the refrigerated space, particularly at a high level therein, the coldest spot will be at the bottom of the container, and that the temperatures will be progressively higher toward the more remote edges of said heat collecting flanges or fins. In a particular case, the latter might be at or above zero F. while the bottom of the metal container would be 50 or more below zero. thinnest toward the remote edges,-and progressively thicker along the lines of heat flow to the bottom of the container on which the solid carbon dioxide; is supported. It will be evident that by this distribution of the insulating host, the direct heatabsorbing effect of the cold bottom of the collection by circulating the evaporated gas in conduits, preferably thin and fiat, arranged around the upper angles of the ceiling and side walls. V 'However, in the preferred case, the

In such case, the frost formation will be gas circulating conduits are dispensed with; the metal capacity; and said collectors are extended as far as may bedesired, sometimes to the walls or even downward on the wall.

In any case, the gas may be discharged inside or outside the refrigerated space, but preferably 7 outside, either to the exterior atmosphere or into the insulation container between exterior wallsof the refrigerator, to there serve asdrying and insulating as well as somewhat refrigerant medium.

Lin section and showing it attached to the roof The above and other features of my invention will be more evident-from the following description in connection with the accompanying drawings, in which Fig. 1 is an enlarged plan view of a form of the bunker designed for various uses in accordance with our present invention;

Fig. 2 is a side elevation of the bunker, partly of a truck or other refrigerator chamber;

Fig. 3 is a vertical section of the bunker, taken on the line 3-3 of Fig. 1';

Fig. 4 is a vertical section taken on the irregular line 4-4 of Fig. 2;

. Fig. 5 is a perspective view of the refrigerant insulated as by wrapping in a number of thicknesses of paper; or by merely supporting on a layer of insulation such as corrugated paper board; or both;

Fig. 6 is a similar view showing-a single chamber' with two bunkers; I

Fig. 7 is a horizontal section of the adjacent refrigerator' chambers each corresponding to Fig. 2 but with the roof removed to show the bunkers in place, the bunkers being different in detail; and

Fig. 8 is a vertical section of refrigerator chamher, the interior and a modified form of bunker being shown in perspective.

The refrigerated space as shown in Figs. 6, 7 and 8, may be the body of an ordinary motor truck or any other refrigerator, and may have any desirable number of doors 3 arid, preferably in' the top, there are hatchways 4,-Fig. 2, each having directly thereunder an opening 8 through tight in any conventional manner and we have for labor in assembling difi'erent parts.

found it very effective and economical to provide inner and outer gas-tight metallicv walls 9 and III with any desirablelthickness of good insulating material, such as kapok or cork, between the said gas-proof walls '8 and 10.

is suddenly warmed, as by opening the service doors.-

The bunker 8 has integral bottom and side walls, and is closed-in by the gas-tight top I8,

except for the opening 6, to permit of charging of same with solid; and said opening has upright walls l5 forming a gas-tight well'or combing that projects up into the hatchway and is sealed therer in by rubber or other gas-tight packing or cement.

The upper surface of the bunker is preferably spaced away from the ceiling any predetermined distance by provision of cross ribs 23, which may be made, say, one-half inch thicker than the balance of thetop I8 so that they not only provide for a space of definite thickness between the bunker and the ceiling of the refrigerator, but also afford a stronger portion" through which the bunker may be fastened to the ceiling, the fastening being accomplished by the screws or bolts passing through the openings 24.

The bunker 8 is preferably of cast aluminum or aluminum alloy, and in a particular case the,

various parts were approximately 1 5' inch in thickness. It has a plurality of heat collecting extensions including-fins l7, extending from the sides and havingthe largest portionof their heat, collecting area, in direct heat-imparting relation to a relatively high level portion of the bunker.

The high level heat collecting surface is further increased by extending thetop l8 of the bunker beyond the vertical sides iii to form lateral flanges Na and preferably thefins II, are formed as brackets supporting said flanges and operating as short circuiting, all-metal conducting paths for flow of heat directly to the lower, colder portions of the walls of the bunker.

In Fig. 2, the bunker is shown in position in a section of the roof of a refrigerator, the hatch- While the bunker 8 may be made of galvanized ir'on, copper'or other metal, or may be fabricated from sheet metal, it is preferably made of aluminum and cast at one operation, thus minimizing the cost and doing away with the necessity The aluminum, or aluminum. alloy is comparatively cheap, is of exceptionally good heat conducting quality. A- shallow bunker of convenient capacity may have its body portion, say, 50" x 14" x 8". The walls of :thecasting may he, say, inch thick, but in any event, the

tal fnay be made thick enough to afford ample cross-section for.

flow of heat; also to afford great heat storage capacity,.which is another way of saying that, when cold, it represents readily and locally available refrigerating capacity which is effective for absorbing'lieat when the refrigerated atmosphere 'jolting of a truck or. refrigerator car.

The openings shown at 29 and plugged by the plugs 30 are placed at any-convenient location and may be used for hooking-up an automatic temperature control, valve operation, or the like. Our invention can be used eitherfor frozen 'or non-frozen products and because of the ab- 'sence of insulation, in the preferred form, around the bunker itself, a very low temperature can be reached in a minimum of time, and by the simple expedient of placing varying amounts of insulation, either around the solid carbon dioxide 20,

'as shown at 2!, Fig. 5; or between it and the metallic bunker, as shown at 22,'we can accurately control theheat absorption, thus controlling the sublimating rate of the solid carbon dioxide and still having the advantages of an uninsulated bunker when the same is desirable.

Theheat is.conducted from the refrigerated atmosphere to the refrigerant through the uninsulated, metal walls, and the heat from more remote and warmer portions is conducted directly to the bunker through the heat collecting extensions ma, [1. The usual top to bottom thermo currents of the atmosphere of the refrigerated space will be set up but will not be as localized in this case as in other refrigerators of this, 75

, the flanges No.

general type, because the relatively great heat absorbing area in'the upper or normally'warmest region will offset thenatural tendency of the bottom to become much colder than the top, and as this difference in temperature between the different regions is what tends to set up such currents they will therefore be greatly diffused. The heat absorbing area is distributed over a wide space, which space may include-practically all of the ceiling ara, this region normally tending to be the warmest and most diflicult to refrigerate. Another advantage is that the various parts are placed almost entirely out of the path of incoming and outgoing products and they will not be subjected to the hazard of injury due to the jolting or sliding around of the cargo while the vehicle is in motion. This also-obviates the necessity for erecting a protecting wall between the lading and the ducts, when a duct system is used; and the ducts may be confined to a high level.

In Fig. '7, the bunker of Figs. 1 to 4 is shown as varied by having the laterally extending flanges l8b as much wider as may be desired. Also the end of the bunker is flanged as at I80, in addition to the side flange shown in the other figures. In the left compartment of Fig. 7, we have shown how instead of widening the integral flanges, supplemental flanges l8d may be bolted or riveted in firm heat conducting contact with I These supplemental flanges 'may be extended to the side walls of the refrigerator, as shown, and theouter edges may be turned down and secured to said side walls, if desired.-

In Fig. 6, the arrangement is like that shown in Fig. ,7, except that the bunkers are supposed to be of'the construction shown in Figs.' 1 to 4,

' and the entire distance between them is bridged by a supplemental sheet metal piece 181:.

In all cases, the supplemental extension may be a casting, or sheet aluminum or sheet copper,

- or any other desired metal.

how the interior of the refrigerator may appear when it is the proper size fora single bunker. In this case the entire bunker construction in- Y cluding heat collecting flanges and brackets may be the same as in Figs. 1 to 4. However, we have utilized this view to show how the bunker may be tapped and supplied with a coupling plate SI for a low level gas-outlet 32'; also how the sides may be similarly providedwith outlet couplings 36a for high level gas conduit connections. Either of these connections may be. used for flat gas flow conduits leading to any desired part of the refrigerator space and if desired, a closed circuit of gas circulation may be conducted from the low level outlet 32around the comers between the roof and side walls, in which case the gas may bereturned through the side high level coupling 3|a. It will be obvio s that the coupling 3| and 3m may be rem ved and imperforate plates bolted on in their'stead; in which case the construction will become to all intents.

and purposes, the same as that shown in Figs. 1 to 4. i

' In most cases we prefer not to discharge the gas into the refrigerated 'spme because air is lighter-and gives a much more lively convection circulation to and from the metal heat collecting surfaces, thereby tending to more rapid equalization of temperature between the top and the bottom. This is highly desirable where service doors are frequently opened.' Also pure air is desirable where the space must be entered 1 for loading or unloading.

the atmosphere to be refrigerated, said container raving heat conducting extensions disposed horizontally from opposite sides of the container at a level at the top side thereof and extending to portions of the chamber remote from the container, and heat collecting fins below said extensions for conducting heat to the container.

2. A refrigerating apparatus including a heat insulated chamber, a metallic container for a solidified gas refrigerant mounted at a high level n the chamber in spaced relation to the chamber walls and uninsulated from the atmosphere in the chamber, said container having heat conducting extensions disposed horizontally' from opposite sides of the container at a level at the upper side of the container, and said extensions extended from the container to opposite side walls of the compartment across the space in the chamber between the container and compartment walls.

3. A refrigerating apparatus including a hea insulated chamber, separate metallic containers for a solidified gas refrigerant mounted at a h gh level in thechamber adjacent but spaced from opposite walls, respectively, of the chamber,-

each of said containers in spaced relat on to the walls of the chamber and uninsulated from the atmosphere to be refrigerated, said con- *a ners each having heat conducting extensions disposed horizontally from opposite sides thereof at a level at the top of the container, and the extensions on facing sides of the conta ners joined to extend across the space in the chamber between said containers.

I 4. A refrigerating apparatus including an insulated chamber. a metallic container for a solidified gas refrigerant supported at a high level in a d chamber spaced from all the chamber walls or circulation of the chamber atmosphere completely there-around, said container uninsulated from the chamber atmosphere and having metall c heat conducting extensions horizontally disp"sed and extending from above the bottom of the container to remote portions of the chamber or conducting heat from such remote portions t the container and a refrigerant therein.

5. A refrigerating apparatus including an insulated chamber to be refrigerated. a container of heat conducting material adapted to receive a solidified gas refrigerant therein. said containcr mounted at a high level in said chamber spaced away from all of the walls of the chamber for circulation of air within the chamber complete-- ly there-around, and the said container having high heat conducting extensions extending from above the bottom ofthe container to the top thereof and terminating in extensions extend-- ing from the top of the container to relatively remote portions of said chamber. 6. A .refrigeratlng apparatus insulated chamber, a container of heat conducting material adapted to be charged with a solidified gas-refrigerant in thermal relation therehaving heat conducting extensions extending from the top of the longer sides of said container above the bottom thereof, to portions of the chamber relatively remote from said refrigerant container. v

7. A refrigerating apparatus including an insulated chamber, a container of heat conducting material adapted to receive a solidified gas re-.

frigerant therein in heat'exhange relation therewith, said refrigerant container mounted 1 in the chamber at a high level adjacent the top wall thereof and uninsulated from and in direct heat conductive relation with the atmosphere within the chamber, the said container being of greater length than width and having heat conducting extensions fextending horizontally from the longer sides of said container from a level near the top thereof, to portions of the chamber relatively remote from the container.

8. A metallic container for a solidified gas refrigerant, having an opening through the top wall for access to the interior of the container, the container top side extended a considerable distance beyond the container side walls to provide metal heat conducting paths from locations relatively remote from the container, and heat colle'cting fins extending from the container side walls below said extended container 'top side.

'9. A relatively thick-walled, cast-metal container for a gas producing refrigerant, said container having'a normally closed top opening for charging the container withrefrigerant and the container walls being substantially without exterior heat insulation, the top side of said container being extended a' considerable distancebeyondthe side walls thereof to provide metallic heat conducting paths to the container from locations relatively remote from the container, and

including an v I heat collecting fins extending from the container side walls below said extended top side of the container.

10-. A metallic container for a solidified gas refrigerant, having the walls of the container -without substantial exterior heat insulation, the

top side of the container being extended a considerable distance beyond a sidewall. of the container to provide a metallic heat conducting path I from a location remote from the container, and

vertically disposed heat conducting fins extend-- side of the container.

11. A metallic container for a solidified gas refrigerant, having the container walls' without exterior heat insulation, the top sideof the container being extended a considerable distance beyond a side wall of thecontainer to provide. a-

heat conducting path from a location remote from and out of substantially direct thermal effect by the wall of the container, and spaced vertically disposed heat conducting fins extending from the wall of the container below said extended top side, the outer ends of the spaces between said fins being open and substantially completely unobstructed through-out the depth I of the outer ends of the fins;

12. A metallic container for a solidified gas refrigerant, said container adapted to be mounted in a chamber to be refrigerated adjacent the top wall of the chamber, the container having tainer having the top side thereof extended beyond a side wall thereof for a considerable dis-.

tance to provide a heat conducting path from a portion of a chamber remote from the container,

and heatconducting fins extending from the container side wall below the extended top side of the container. s

13. A refrigerating apparatus including in combination, an insulated chamber to be refrigerated, a'metallic container for a solidified gas refrigerant, mounted in said chamber at a high level adjacent the top wall of the chamber, said container being uninsulated from the atmosphere in the chamber and spaced from' the top wall and remaining walls of the chamber for circulation of i the chamber atmosphere completely .around and over the container, and said container provided with heat conducting extensions disposed substantially horizontally from opposite sides thereof at a level adjacent the top of the container, said extensions extending considerable distances across the chamber to portions of the chamber atmosphere remote andremoved from I the direct thermal effect of the uninsulated con tainer.

14. A refrigerating apparatus. comprising an insulated chamber, a container for solid carbon dioxide at a highlevel therein and uninsulated from the atmosphere to be refrigerated, said container being of greater length than width and having" high heat conducting extensions extend-- ing from the longer sides of said container and increasingin area from the bottom towards the top, and from a point near the top of said container.

15. vA metallic container for a refrigerant, having an opening for access to theinterior thereof and having the .top side extending beyond the side 'walls thereof and heat collecting fins below and in contact withsaid extended top, and arranged at right angles thereto.

16. A metallic container for a refrigerant, havingan opening for access to the interior thereof .and having the top side extending beyond the side walls thereof and heat collecting fins, extending from said side walls below said extended top and being of increasing area towards the top.

17. A metallic container for a refrigerant, having an opening for access to the interior thereof and having the top side extending beyond the side walls thereof and heat collecting fins ex-' tending at right angles from said side walls and connectedto said top.

' CHARLES -L. JONES.

HQWARD s. McILVAIN.

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