US1992889A

US1992889A - Method and apparatus for refrigeration

Info

Publication number: US1992889A
Application number: US741465A
Authority: US
Inventors: Jr Edward Rice
Original assignee: Individual
Current assignee: Individual
Priority date: 1930-07-14
Filing date: 1934-08-25
Publication date: 1935-02-26
Anticipated expiration: 1952-02-26

Description

Feb 26, 1935. E. RICE, JR

METHOD AND APPARATUS FOR RFRIGERATION ll Sheets-Sheet 1 Original Filed July 14, 1930 -..nw-.1.. nu...

lldr Feb. 26, 1935. E. RICE, JR .1,992,889

Y METHOD AND APPARATUS FOR REFRIGERATION original Filed July 14, 1930 1l sheets-sheet 2 I l w n l l s s E s l;

furvlfvn vlrl ulllhllll vrrlrfllilrlnllvrlnlllvl/lffr Feb. 26, 1935. E. RICE, JR

METHOD AND APPARATUS FOR REFRIGERATION inal Filed July 14, 1950 ll Sheets-Sheet 3 Orig Feb. 26, 1935. E. RICE, JR 1,992,889

METHOD AND. APPARATUS FOR REFRIGERATION Original Filed-July 14, 1950 l1 Sheets-Sheet 4 'JAL Feb. 26, v192.5'.

E. RICE, JR

METHOD AND APPARATUS FOR REFRIGERATION Original Filed July 14, 1950A ll Sheets-Sheet 5 Feb. 26, 1935. l E MCE, JR 1,992,889

METHOD AND APPARATUS FOR REFIGERATION originall Filed July 14, 1930 1v1 sheetsfsneet 6 Feb. 26, 1935. l E. RlCE, JR 1,992,889

METHOD AND APPARATUS FOR REFRIGERATION original piled July 14, 1930 11 sgeets-spet 7 Feb. 26, 1935. E, RICE, JR 1,992,839

METHOD AND APPARATUS FOR REFRIGERATION Original Filed- July 14, 1930 ll Sheets-Sheet 8 Feb. 26, 1935. E. MCE, JR

METHOD AND APPARATUS FOR REFRIGERATION ll Sheets-Sheet 9 OriginalY Filed July 14, 1930 Feb. 26, 1935. E. RICE, JR

METHOD AND APPARATUS FOR REFRIGERATION l1 sheets-sheet 1o Original Filed July 14, 1930 Feb. 26, 1935. E R|E, JR

METHOD AND APPARATUS FOR REFRIGERATION Original Filed ,July 14, 1930 ll Sheets-Sheet 11 Patented Feb. 2s, 193s 4 UNITED s'rfrlzsll PATENT OFFICE Y. 1,992,889 f i METHOD AND APPARATUS ron narnia-Enanos Edward liice, Jr., New York; N. Y. Original application July 14, 1930, Serial No.

30 Claims.

A faces of a heat vconductor and is transmitted by the conductor to adjacent' surfaces of the lsolid refrigerant. This is accomplished by vproviding an obstruction in the path of heat flow formed by the conductor whereby the heat 'ow is re`- stricted, or varied as desired. 'I'he obstruction consists of any convenient medium of thermal transfer resistance and is preferably located between the surface of the conductor presented in the refrigerant containing space and the opposing surface of the refrigerant. In accordance with the established laws of physics, the thickness andinsulating character of this obstruction determines' the rate of heat exchange between -the conductor and refrigerant and thereby the temperature of theextended heat absorbing surfaces of the conductor, and in turn the temperature of the refrigerated space lor material.

Thev nature and structure of the resistance and of the conductor is determind by the character and melting point of the solid refrigerant used and the refrigerating temperatures desired.- 'I'he conductor and refrigerant containing space are preferably constructed as illustrated so that the solid refrigerant is maintained by gravity in heat exchange relation with the conductor, although any means maybe used for maintaining the desired relation.

A principal object of the'linvention is to provide a method of refrigerating by means of solid refrigerants that shall bemore eilicient than the priormethods and shall permit of close regulation of the effective refrigerating temperatures.-

Another object of the invention is to provide a method of' refrigerating'by means of solid refrigerants whereby the eifective4 refrigerating temperatures areA to be a substantial degreeindependent of -the volume of .the refrigerant, and to this latter end.. the invention contemplates the provision of 'a method for materially increasing the. refrigerating efficiency of relatively small `quantities of 4a solidrefrigerant.

Divided and this application August 25, 1934, Serial No. 741,465

Amilssutu stm another objeet 'of the .invention 1sthe provision of a method of refrigerating by use of eration of practically any desired space whether occupied with a gas (including air), liquid; solid or a combination thereof without actual contact of the refrigerant with the contents of the space whereby when required the refrigrant may be' entirely divorced from the refrigerated area.

A still futher object of the invention is the provision of refrigerating apparatus for u'se with a solid refrigerant in whch the principal heat transfer to therefrigerant takes place from the refrigerated space or mass to a condutor of high thermal conductivity and extended surface', and thence conductively to a relatively small surface of the'refrigerant through a section` of the conductor sufficiently large .to transmit lthe required amount of heat for maintaining a predetermined effective refrigerating temperature. p

'Ihe invention further contemplates the provision of'refrigerating apparatus for use interchangeably with solid C02, solid H2O or other solid refrigerant, in which the principal heat transfer to the solid refrigerant takes place from the refrigerated area or mass to a conductor of high thermal conductivity and extended srface, Vthence conductively to a relatively small surface of the refrigerant through a section of the conductor of suillcient size to transmit an amount of heat required for maintaining a predetermined effective refrigerating temperature and in which differences in the melting or subliming temperatures of the different refrigerants-maybe compensated by means of variable conductor resistances placed between thev conductor and the refrigerant.

Again specifically, and as regards the use of solid refrgerants, such as solid CO2. having a relatively low melting point or` point of sublima tion, another object of the invention is to provide a method of refrigerating with such refrigerants Awhich shall be both relatively eilcient and capable of close and accurate regulation of the of outside atmospheric temperature, of content' A still further object is the provision of refrigerating apparatus for use with solid CO2 or the, like in which the effective refrigerating temperature is controllable at least in part by means of insulation set up inan established principal path of heat travel between the refrigerated area or mass and the refrigerant. u

A still further object -of the invention is to provide a refrigerating apparatus for use with solid CO2 or the like in which provision is made for varying the effectiverefrigerating tempera'- ture by means of an obstruction in the principal path of heat travel between the refrigerated area or mass and the refrigerant and in which said obstruction may be inserted, removed or varied either manually or thermostaticallly during the refrigerating operation.

A further and more specic object of the invention is the provision of a method of refrigeration by the use of carbon-dioxide ice or the like which will permit the automatic maintenance of l' an approximately constant temperature in therefrigerating chamber under varying conditions of refrigerating chamber, and of ice supply. I

' A further object of the invention is the provision f refrigerating apparatus for use with CO2 l ice orthe like inwhich the principal heat transescaping CO2 gas.

' fer from the refrigerating chamber and its congas-tight channels away from the contents of the refrigerating chamber, and in which the gas escapes directly to the outside. atmosphere or Y.

through piping of' high thermalconductivity placed in the top of the refrigerating chamber., thus permitting a secondary heat transfer from therefrigerating chamber and its contents to the A further object' of the Vinvention is to provide a method of and apparatus for refrigerating by the use of CO2 ice or the like whereby an initial .-aapid chilling of the refrigerating chamber or Iits contents may be had when desirable by a com- -paratively rapid melting or sublimation of the ice; and thereafter the required temperature maintained by a much slower sublimation of the ice store. v

A further object 'of the invention is to provide sucha refrigeratingl apparatus for use with CO2 -vt icef or, the like 'that a regulated temperature either above or below 'the freezing temperature of water can be maintained in the--principa1 refrigerating chamber, while in a. second chamber thetemperature is not exactly regulated, but will and in specific embodiments representing various applications thereof to different classes of refrigeration, all as hereinafterv set forth and illustrated inthe attached drawings, in which:

Figure 1 is a diagrammatic sectional view illustrating an embodiment of my invention;

Fig. 2 is a fragmentary sectional viewY of the embodiment shown in Fig. 1 modified for use with solid CO2 as the refrigerant;

Fig. 3 is a section on the line 3.-3, Fig. 1;

Fig. 4 is a fragmentary sectional view similar to that of Fig. 2 but illustrating the apparatus u sed with a refrigerant composed of frozen brine;

Fig. 5 is a sectional view illustrating an embodiment of my invention modified for use with solid CO2;

Figs. 6, 7, 8, 9 and 10 are fragmentary sectional views illustrating different types of nn construction suitable for use in the practice of my invention;

Fig. 11 is a diagrammatic sectional View illustratinga still further embodiment of my invention;

Fig. 12 is a section on the line 12'-12, Fig. 11;

Fig. 1'3 is a diagrammatic-sectional view illustrating another embodiment of the invention;

Fig. 14 is a diagrammatic sectional view illustrating application ofthe principles `of my invention to the construction of a container for frozen product such as ice cream; y

Fig. 15 is a section on the line 15-15, Fig. 14; Fig..16 is a diagrammatic sectional view illustrating a modification of the embodiment illustrated in Fig. 14;'

Fig. 17 is a section on vthe line 17-17, Fig. 16;

Fig. 18 shows another form of refrigerator storage cabinet embodying my invention;

Fig. 19 is a section on the line 19-19, Fig. 18; f

Fig. 20 is a vertical sectional view showing a further form of single chamber container made in accordance with my invention;

Fig. 21 is a sectionn the line 21--21, 20;

Figs. 22 and 23 are vertical sectional views illustrating my invention as embodied in relatively small refrigerator containers;

Figs. 24 and 25 are, respectively, a vertical sectional view and a section taken on the line 25-25, Fig. 24, illustrating a table-or cabinet type of refrigerator made in accordance with myV invention and in condition for use with solid carbon dioxide or other refrigerant of relatively.y low melting point;

Fig. 26 is a vertical sectional view through a small type of shipping refrigerator containerA made in accordance with my invention;

Fig. 27 is a section on the line 2'7-27, Fig. 26;

' Fig. 28 is a plan view of another form of refrigerator employing my methodand apparaus; l

Fig. 29 is a section on line 29-29 of Fig. 28; Fig.- 30 is a4 section on line 30--30 of Fig. 29; Fig. -31 is a vertical sectional view through a moded refrigeratorstructure;

Fig. 32 is a section on line 32--32 of Fig. 31;

Fig. 33 is a horizontal sectional view of a further modied form of the invention. taken on the line 33-33 of Fig. 34;

Fig. 34 is a section online 34--34 of Fig. 33; Y

Fig. '35 is a. fragmentary bottom plan view of a conductor` plate constructed for`use in my apparatus;

. Fig. '36 is a fragmentary' modified view of a slightly modified form of a conductor plate wherein the vanes are transversely corrugated to increase the conduction surface thereof;

Fig, 37 s a fragmentary side elevation of the plate illustrated in the vertical corrugation of the vanes for the same purpose;

Fig. 38 is a front elevation of a household refrigerator constructed in accordance with my invention and adapted dfor making water ice cubes and storage of frozen products;

Fig. 39 is a horizontal sectional View on line 39-39-'of Fig. 40;

Fig; 40 is a vvertical sectional view on line 40-40 of Fig. 39; f

Fig. 41 is a horizontal sectional View taken on line 41-41 of'Fig. 42 and illustrating a modication of a structure, such as shown in Figs. 38 to 40, to produce aj circular refrigerator having rotating shelves; 41Fig. 42 is` a section on the line42 -42 of Fig.

Fig. 43 is a fragmentary vertical sectional view illustrating a modification of the invention com,

. meat, fish and other foodstus /also embodying Fig. 45 is a horizontal sectional view, and

Fig. 46 is a vertical sectional view on the line 46-46, Fig. 45, illustrating my invention as applied to refrigeration of relatively small truck bodies;

4o' shown in the immediately preceding figures in j .eration of any enclosed space;

than-any other form of refrigerant.

Fig. 47 is a vertical sectional view of a refrigerating unit made in accordance with Amy invention and lof a type applicable to the refrig Fig. 4a is a section on'the une 1c-4a, Fig. 47; and

Fig. 49 is a diagrammatic horizontal sectional view illustrating the use. ofaunit of the'type refrigerating the various compartments of a truck or `foar. f

Water ice or solid H2O is more Widely used One of thel principaldrawbacks in the prior methods of using this refrigerantor,l in fact, any 4solicl refrigerant is .that although any given 'mass of. the refrigerant, no matter how small, has a fixed refrigerating. value; yet the smaller the mass becomes, the slower its refrigerating action becomes also. 'I'his is due to the fact that the' heat given no consideration, .and no effort has been inferior results.

made to compensate for the. rapid decrease in efliciency as the refrigerant loses volume Land surface area. As a result, a great deal of ice is constantly being used 'with very indifferent or One reason that the mechanical household refrigerator has progressed so l'rapidly is because the ordinary water ice refrigerator cannotmaintain satisfactory refrigeration unless it is contin- .ually serviced and kept practically full of ice at For the same reason, -a largev andbrine through4 the metal container, however, is growing eldfor refrigeration of foodstuffs in not as constant and controllable as in the direct 75' all times;

motor transportation has avoided the use of water ice and other Vsolid refrigerants. Practically the only method attempted to improve the eiliciency of .water ice as a refrigerant has been the use of salt, a method of limited application which apparently cannot be greatly extended.

I have discovered that the principal obstacles .to the efficient use of waterice and other solid refrigerants can-be largely overcome if the heat from the space or material to be refrigerated is picked up by comparatively extended surfaces of a metal heat conductor, such as copper, aluminum -or iron, and transferred through a subl stantial cross section of the metal conductor directly to. a surface of the body of ice with which the metal conductor is either in immediate contact or'in suitable conductive relation. I have 'found that by this method, the ice can be meltedl at practically a vconstant rate, thus providing a constant effective refrigerating temperature practically independentv of the volume of the refrigerant, and even with extremely small masses of the latter. I have found also that the refrigerant can be melted at an almost inconceivable rate when large amounts-of heat are passed over the extended metal surfaces. a. suflicient cross section of the conductor metal, as small as thirtyA square inches of contact surface with 'the refrigerant will suilice to melt enough water ice to keep a good'household re' .frigeratorbelow 50 F. even on the top shelf in the warmest weather; and after the doors havev been opened as long as three minutes; this refrigerator will return to Vits original low temperaturewithin twenty minutes or one-half hour. It is essential in the practice of my invention that the solid refrigerant be maintained in condlrctive relation with a substantial metal conductor'having a suitably extended surface area 4in the refrigerated space.

While the invention is of great importance in conjunction with the use of water ice, it is also of great value in the use of all other solid re-` .-frigerants, such as s olid carbon dioxide and frozen brine. The apparatus embodying my invention need vary only slightly to meet the requirements lof the particular kind -of refriger. ant Vand the type of refrigeration required. If,

for example, refrigerating temperatures around` 35 to 45 F. vare desired and water ice is to be used by reason of its cheapness and availability, then a relatively large amount of extended conductor or n surface will be required because of` the small temperature/differential betweenthev temperature diiferential be maintained between the conductor and. the refrigerated space. Obviously if temperatures are wanted near or below the melting point of water ice, then some lother solid refrigerant may bevused with a sufflciently lowmelting or subliming point that the 1 conductor 'can be put at a temperature affording the differential required to maintain the refrigeration wanted. Frozen brine may lbe used es-i vpecially when put up in small and easily. handled units in liquid-tight metal containers. heat-transferred-'from the yconductor to the-solid contact of water ice with the conductor or the contact of carbon dioxide ice with the conductor" through a known amount of conducting resistance, as hereinafter more specifically set forth. However, as the frozenbrine can be provided with a melting point practically anywhere between 32 F. and considerably below zero and has now come into more common use and also is comparatively cheap, it is apparent that it Will have a limited use as a solid refrigerant means in my method of refrigeration. Of course, frozen brine directly in solid state can be used `in the same way as water ice or carbon dioxide ice by permitting the melted brine tov drain oi.

When using solid refrigerants such as Vcarbon dioxide ice with a temperature considerably below the melting point of water ice, the use of predetermined known conductor resistances interposed between the conductor and the refrigerant is an important part of my method, as it affords a large degree of control over the action of -the refrigerant and a quick convenient method of varying the temperature ofthe extended conductor surface, and thusthe effective refrigerating temperature.

It will be understood that for maximum control of refrigeration, with this type of refrigerant it is desirable to limit so far as feasible transfer of heat from the 'refrigerated space or mass to that passing through the conductor. This can be accomplished by providing adequate insulation preventing transfer by radiation or by other than conduction through the selected conductor. By thusV establishing a principal and practically sole path of transfer and utilizing in conjunction therewith suitable known resistances,'a substantially perfect control may be obtained. This method of controlalsoaifords a simple method for providing apparatus suitable for use with refrigerants such as water ice and i carbon dioxide ice having widely different melting points. Thus a single refrigerating apparatuscan be built that can use as a refrigerant either carbon dioxide or water ice or frozen brine, or, in fact, any solid refrigerant', and that can maintain practically any required temperature under constant outside temperature conditionsvwithin the limits .ofthe particular refrigerant used by a simple manipulation of conductor resistance interposed between the conductor and the refrigerant, and by providing in the same apparatus either manually or thermostatically-'operated means to regulate the convection currents from the extended conductor surfaces or fins, the required temperature can bel maintained irrespective of normal outside temperature variations.

In Figs. 1 to 4, inclusive, I have illustrated application of the invention to a refrigeratorof the overhead icing type. In this instance, the.

casing 25 has in its interior and upper portion a refrigerant-supporting .shelf 426 which hinclines fromopposite sides towards the center whereby a solid refrigerant placed thereon has a tendency to gravitate toward the conter. From the depressed mid-section Ia drain-pipe 27 extends downwardly passing between the ns and inv contact with the modified for use with solid carbon dioxide. In.

this instance, conductor resistance in the form of sheets 31 of heat-insulating character is interposed between the ice and the conductor shelf 26. Also the solid carbon dioxide is completely surrounded by insulation 32. The refrigerant is in conductive relation with the conductor 26 through the resistance 31, which is of predetermined value and selected to maintain a predetermined effective refrigerating temperature. limation may escape through the pipe 27. It will be noted both as regards the use of waterice and dry refrigerant, a conductive relation between the refrigerant and the conductor 26 is maintained.

In Fig. 4, Ihave illustrated the same apparatus used with frozen brine containers 33. These containers with the brine in the solid state are supported upon the shelf `26, suitable conductor resistance 31 being inserted between .the Vconductor 26 and thel said containers, and the latter also being surrounded by suitable insulation 32. In this instance, the drain pipe from the shelf 26 is eliminated.

Gases of sub- Fig. 5 shows a type of conduct-or of primary down the upright side of the casting to the bottom or ice-supporting wall. Interposed between the solid carbon dioxide and this lower wall is a suitably selected vconductor resistance 4.2, and the ice is also surrounded by suitable insulation 43.

In Figs. 6 to 10, inclusive, I have illustrated various types of fin conductors which have been found suitable in the practice of my invention.

The form of conductor illustrated in Fig. 6 is one that can be conveniently used for household refrigeration purposes, this being made up from a number .of bent copper sheets 45 soldered together at the points designated 46 so as to present a substantially iiat conductor plate surface for contact with the solid refrigerant and a considerably extended fin surface for contact with the convection currents;

Fig. 7 shows a similar construction in which the outer ends 47 of the projecting iin portions are turned inwardly toward each other so as to afford the same amount-of contactsurface in a more restricted space.

Fig. 8 shows a more efficient type of conductor in which thin copper fins 48 are soldered or vwelded to a heavy copper conductor plate 49.

Fig. 9 shows a still more eicient but more Aexpensive form of conductor consisting of a solid aluminuiriK plate 51 with thin copper fins 52 secured to the' aluminum plate by-casting the latter on the ns.

Fig. 10 shows an all-aluminumin conductor formed of a single casting. Y

In Fig. 1l, I have illustrated my invention as applied to a water cooler employing solid carbon dioxide as the refrigerating medium. In this instance, the conductor forming an essential part of the device consists of a solid aluminum or copperlreceiptacle 55 which is embedded in solid insulation 56. A chamber 57 is provided in the insulation 56 for the water or other liquid to be n perature of the conductor.

' ing ice cream, frozen foods or the like.

cooled. This chamber, as shown in Fig. 12, extends completely around the sides of the receptacle 55, but is spaced a suicient distance from the said conductor to maintain a desired temperature of the liquid for any predetermined tem- This temperature in turn is controlled by thethickness of conductor resistance 58 interposed between the solid car` bon dioxide ice and the bottom wall of the conductor. With an arrangement of'this character, I have found it possible tomaintain substantially any desired temperature of the liquid within the container 57 by simple variation in the thickness of the conductor resistance 58 which modifies the conductive relation between the conductor 55 and the refrigerant. It Will. be noted that in this instance the conductor while having the necessary extended surface is not provided with ns, and that further the .surfaces of the conductor are not in direct contact with the liquid to be cooled, but are in conductive relation` therewith through the insulation separating the walls of the liquid container from the said conductor.

Fig. 13 shows a similarly constructed water cooler with the addition of a storage space 60 located below the bottom of the conductor, it being possible to maintain this space at practically any required temperature by variation in the thickness of the insulating member 70 which constitutes conductor resistance between the space and the bottom of the conductor 55. I

A more or less similar form of conductor is shown in Figs. 14 and l5, which show a cabinet suitable for use with solid carbon dioxide for stor- In this instance, the conductor consists of a solid aluminum casting 62, this casting comprising a base 63 and four cylindrical vertical containers 64. In this instance, the walls of the portions 64 constitute the necessary extended surface area, provision being made for supportingthe refrigerant upon the base between the said portions 64, as shown in Fig. 15.- For this purpose, the refrigerant may: be supported within a vertical metallic or other container open at the bottom to permit the ice to come into conductive relation with the base portion 63 of the conductor, from which it may be separated by a suitable conductor resistance member 65 selected to afford a desired temperature within the receptacle 64 in which the refrigerated material is stored. The entire conductor casting is surrounded by a suitable insulating casing 66, and provision is made in the form of removable cover plates 67 for affording access tothe interior of the container 64.

In Figs. 16 and 17, I have illustrated a similar type of refrigerating apparatus which in addition includes storage -chambers or receptacles 67 embedded in the insulating casing 66 in suitably spaced relation to the' sides of the container 64, these compartments 67 being readily kept at.

a non-freezing temperature and being suitable for holding Water or other substances or mate/- rials at a relatively low but non-,freezing temperature.

In Figs. 18 and y19, I show a form of refrigerating storage boxlconvenient for use on store counters and under similar conditions. In this instance, the storage space is surrounded on three sides and the bottom by the conductor 85, and the heat is picked up as it4 comes through the v walls of the storage box and also from the conductor, and thence to the .refrigerant shown asv blocks of solid carbon dioxide, which is separated fromv the conductor by the conductor resistance 86 generally used with this refrigerant. It will be noted that the chamber which holds the refrigerant is separated Ifrom the storage chambers `on the base of the conductor with the usual interposed conductor resistance 93. A small removable shelf 94 is placed over the ice to support the ice cream can or other materials to be stored. A vent 95 affords escape of the sublimed gases or meltage.

In the embodiment shown in Fig. 22, a small storage box adapted for use primarily with CO2 ice is shown. In this instance, the conductor takes the form of a rectangular container 96 which is open at one side, and provision is made for placing the refrigerant on the top wall of the conductor as illustrated, the usual conductor resistance 97 being provided. Access to the ice chamber is afforded through a removable cover 98 in the insulating casing 99, and access to the refrigerating chamber is provided by a suitable removable cover member (not shown) located in the side of the said casing.

Fig. 23 shows still another form of small storage box in which the conductor 101 is in the form .of a removable storage bin, this conductor being made preferably f copper or aluminum. Access to the storage space is afforded through a removable cover 102 in the top of the insulating casing 103, and this top portion 104 of the casing is also hinged at 105 yto permit the entire top to be turned back to permit removal of the conductor 101. The refrigerant in this instance is supported upon a shelf 106 which is movable within the casing and which has legs 107 which project through openings in the bottom of the casing and rest upon the oor or other supporting surface. As the CO2 ice sublimes, the entire casing settles downwardly around the shelf 106, wherebythe refrigerant is maintained in continuous conductive relation with the bottom of the i conductor 101. The usual conductor resistance 108 is interposed between the refrigerant and the bottom of the conductor.

In Figs. 24 and 25, I have illustrated a large table or cabinet type of refrigerator adapted for use either with CO2 ice or water ice and in which provision is made for obtaining in the three separate compartments three different temperatures, when CO2 ice is used, or of two temperatures when water ice is employed. This refrigerator consists of an outer insulated casing 111 having in the top a chamber for a, refrigerant, the opposite sides and the bottom of which are constituted by a channel-shaped conductor 112. 'Ihe side walls of this conductor are provided with outwardly projecting fins 113, and the bottom wall a tendency of the solid refrigerant to move by gravity towards the vertical fin walls. Access to this refrigerating chamber is had through a' removable cover 114. Three refrigerating cham- `is slightly elevated towards the center to create bers are provided numbered 115, 116 and 117, respectively, the chamber 116 being located directly below the refrigerant chamber.V Baflles 118 in the chambers and 117 extend vertically and preferably in Contact with the outer edges of the ns 113 whereby a convective circulation is set up in which the air moves downwardly between the ns and against the side walls of the conductor. The chamber 116 is separated from the other chambers by insulating walls 119, and in one or both of the chambers 115 a valve 120, which may be operated manually or automati- -cally from a suitable thermostatic actuator, is

provided for controlling the movement of the con-- vection currents downwardly past the Walls and ins of the conductor. Where carbon dioxide ice is used, the refrigerant is surrounded in the refrigerating chamber on four sides and the top by suitable insulation 121, while the ice is separated from the bottom of the conductor by means of suitable conductor resistance 122. 'I'he temperature in the chamber 116 is controlled by the thickness and character of the conductor resistance, whereas the temperatures in the

compartments

115 and 117 are controlled not only by the conductor resistance, but also by the thickness and character of the insulation 121, and may be still further controlled by manipulation of the valve 120.

Figs. 26 and 27 illustrate a small shipping refrigerator box in which the conductor 126, which may suitably be made of copper or aluminum, in effect lines the four walls and bottom of the casing 127. This form of refrigerator is particularly suited for use with CO2 ice, and it will be noted that the usual protective Vinsulation 128 and conductor resistance 129 are provided. Referring to Figs. 28, 29 and 30, numeral 140 designates a refrigerating chamber having access doors 141 in the upper wall 142 thereof. The

chamber walls are, of course, insulated in anyV usual or preferred manner and the upper wall`14t2 has formed therein an opening 143. Extending into the refrigerating chamber through this opening is an insulated cabinet 144 approximately gas tight having an open top closed by an access door 145. The bottom wall 144a of this cabinet has imposed thereon a conductor plate 146 which may be conveniently constructed from copper, aluminum or some other metal having a suitably high factor of thermal conductivity. The edges of this plate proa'ect through the cabinet walls and are provided withvvertically-extending varies 147 projecting upwardly along the side walls of the cabinet and preferably constructed integrally with the plate 146. These vanes, as evidenced by Figs. 35, 36 and 37, may be either plane, as in Fig. 35, or transversely or longitudinally corrugated, as indicated at 147 and 1471), respectively, in Figs. 35 and 36, the latter constructions proividing an increased surface for contact with convection currents.

Opposing the outer edges of the vanes are insulated walls 148 which combine with the cabinet to provide channels 149 through which convection currents may pass. The lower ends of these channels are closed by valves 150 regulated through a thermostat 151. In the present instance, the valves are illustrated as pivotally connected to the lower wall of the cabinet at 152 and connected to the movable element 153 of the thermostat by a linkage generallyfdesignated at 154.

From the interior of the cabinet a vent tube 1515 is led through the wall of the refrigerating chamber 140. This vent tube is made of metal of a high thermal conductivity, preferably copper, and includes a coil 155e disposed in chamber 140 for contact with the 'convection currents of the chamber, preferably near the top of the chamber and where warm pockets are liable to occur. The outlet of the vent tube is placed below the inlet in order to induce a ready flow of CO2 gas by siphoning, and is preferably equipped with a regulating valve which may be conveniently housed in a recess formed in the wall of the cabinet.

The interior of the cabinet is preferably subdivided into a plurality of sections by vertically extending partitions -159 constructed of insulating material. 'I'hese partitions are in the present instance illustrated as two in number so that three ice spaces are formed.` The bottoms of these ice spaces are formed by the plate 146 and upon the plate in the bottom of each ice space insulation 160 may be disposed between the ice and the plate, the thickness of this insulation varying in accordance withthe conditions under which the refrigerator is to be employed'. Insulation 160 is removable` and of variable thickness and it will be obvious that if two of the compartments have in the bottoms thereof insulation 160 of a considerable thickness while a third compartment has no insulation as suggested in Figs. 28, 29 and 30, or a relatively thin insulation as suggested in Fig. 34

the ice of this latter compartment will be sublimed more rapidly than that in the remaining compartments so that the ice of this compartment Vacts as an initial chilling supply While that of the remaining -compartments acts as a reserve supply. Thus the first mentioned ice supply serves to rapidly reduce the temperature of the chamber when initiallyr placed in operation or when a rapid reduction of temperature therein is necessary following an opening of the access doors '141.

If, for example, goods are placed in the re-v frigerator at their normal temperature and must be rapidly chilled, the insulation 160 may be completely removed from one of the compartments so that the ice in this compartment ,will act very rapidly to reduce the temperature of the chamber and to chill the goods to the desired point. The desired temperature having been attained, the ice in the remaining compartments is held in reserve to maintain thistemperature, thus materially increasing the period over which refrigeration is possible and particularly adapting the apparatus for use in transportation of perishable goods where facilities for replenishing the "ice store are poor.

When precooled products are placed in the refrigerating chamber, then the bottoms of all of the compartments may be provided with insulation, thus providing a maximum period of refrigeration for a given ice supply. By varying the extent to which the bottoms of the comspaces of the refrigerating chamber are preferably separated from the cabinet spaces by foraminous screens 162. A

The principal amount of the heat used in melting, or subliming the ice is transferred by'conthe insulated chamber walls and doors.

vectionvfrom the storage chamberand its contents to the vertically extending vanes 147, thence conductively to the plate 146, thence conductively directly, or through insulation 160 to the ice, A smaller amount of heat is transferred by conduction through the insulations of the "ice cabinet and walls 148, and by internal convection currents'within the ice cabinet and space 147a. Control of the temperature of vthe storage chamber and contents is secured in part by predetermined fixed variations of the size and character of the conduction plate 146 and vanes 147, and of the

insulations

144, 144e, 148, 150 and However, actual changes in temperature in the contents of the storage chamber during reduction to a desired level, as well as climatic and artificial changes in temperature outside the storage chamber may require a further means for securing aV constant temperature inside the chamber. This is achieved by the thermostatic or manual control of the convection currents through channels v149 and transferring more or less heat to conduction vanes 147 and plate 146. By these several means a variation of the rate of subliming or melting the carbon-dioxide ice of asv much as 1,000% can be attained which I believe is sufficient to accomplish the objects of this invention.

The structure of Figs. 31 and 32 is substantially identical with that of Figs. 28, 29 and 30, with the exception of the fact that the chamber 140 has its access door 141a mounted in the 4side wall thereof vand that communication between the channels 149 and the storage space in the upper endsA ofthese channels instead of being made only through openings 163, formed in the insulating walls, includes one or more ducts 164 opening at the inner end through the wall of channel 149 and having the outerend disposed adjacent to the wall of the chamber 140 or where warm pockets are likely to occur. A further slight modification of the'control of the channelis employed in that the valves 150a instead of being supported by the cabinet, as in Figs. 28, 29 and 30, are directly supported from and secured to the movable member 153 of the thermostat. The thermostat has further associated therewith bafile shields 165 which prevent chilled air, descending from the convection channels, from directly contacting thermostat 151 and thus causing too early a closing operation of the valves 150a. I

The form shown in Figs. 33 and 34 is identical with the structure of Figs. 31 and 32, with the exception of the fact that conduction vanes are provided entirely about the cabinet walls and entrance to the convection channels is largely through ducts 164a, the intake ends of which are disposed adjacent to the vertical Walls of the chamber 140.

In Figs. 38, 39 and 40, I have illustrated refri'geration apparatus particularly adapted for household uses and embodying means for pro? ing pans 168 for the formation of ice cubes or used in freezing confections or for storing frozen ply may rest at its lower end directly upon the plate 146, or uponportable insulation 160A as de,- scribed above. The ice cube and frozen storage compartment 166 may, however, belconveniently combined with structures embodying several vertical columns of "ice as suggested in Fig. 43.

In Figs. 41 and 42, the construction ofi Figs. 38 to 40 is modified to permit its adaptation Ato a circular refrigerator having rotating shelving units 171, the rotation of which will bring storage into alignment with an access door 172 which aligns with the access door of the freezing chamber 166.

In Fig. 44 is illustrated an apparatus made in accordance with my invention adapted forquck freezing of meat, fish and similar products. A casing 203 has established therein a conductor plate 204, this plate being adapted to slide vertically in the casing. Depending from the plate 204 is an insulating apron 205 which fits more or less closely around a post or ram 206 also preferably of insulating material. When a refrigerant is placed between the upper end of the ram 206 and the plate 204 and within the space sur# rounded by the apron 205, it will be apparent that the plate will be supported by the refrigerant, and that as the latter melts or sublimes, the plate will move downwardlyQso that the conductive relation between the plate and the refrgerantwill remain constant. AWhere a refrigerant such as solid CO2 is employed, temperatures may best be controlled by a conductor resistance 207 inserted between the refrigerant and the plate as yillus- In this illustration, wheretrated. An upper plate 208 is' provided having at the top an enclosed insulated space 209 for reception of a refrigerant which is held in conductive relation to the plate 20-8. This plate `208l rests upon the material to be frozen, which latter in turn rests upon the plate 204, so that the material is confined between the two cold plates, insuring rapid freezing. Where arefrigerant of the type of solid CO2 is used, it is preferred to employ a conductor resistance 211 which is interposed between the plate 208 and the refrigerant as illustrated. l

In Figs. and 46, a refrigerating system is illustrated suitable for small truck bodies and the like and adapted for refrigeration with practically any type of solid refrigerant. The body 221 in this instance has a chamber 222 at one endA and in the upper portion for reception of the refrigerant, the bottom and front wall of this' space being constituted by a suitable angular conductor plate 223, and the said front wall being provided with fins 224 which projectinto the interior or refrigerated area'of thel truck.` The space directly `under the bottom of the -conductor plate 223 is enclosed by a partition 225 and constitutes a cold compartment whose temperature may be maintained at a relatively low point. A false wall or baffle 226 is provided in the interior of the body which forms a channel for the circulation of the convection currents, as in' dicated by the arrows, the circulating air passing downwardly over the upright face of the conductor 223 and between the fins 224.v I also may provide in this instance a valve 227 in the air .passage whereby the circulation of air may be controlled either manually or'by a suitable thermostat, thereby affording a further control of the interior temperature of the truck. Where, as illustrated, a refrigerant such as solid-carbon dioxide is employed, this refrigerant will be surrounded by an insulating sleeve 228 and separated from `the bottom of the conductor memberby a suitable conductor resistance element 229. The temperatures may be controlled by regulating the thickness-andcharacter of the-conductor resistance and of vthe insulating sleeve 228.

. Where Water ice is employedthe sleeve 228 and conductor resistance 229 maybe eliminated. It will be noted that in this case also I employ on the top of the truck body a suitable radiation.

shield 231.

Figs. 47 and 48 illustrate a unit of portable character which may be applied Asuccessfully to the refrigeration of any desired enclosedspace. The unit consists of t-he .usual thermal conductor 255 in the form of a container, three side walls of which are provided with outwardly projecting ns 256 and being provided also with baffles 257 secured to the outer edges of the fins and extending to a point short of the tops of the latter. The refrigerant may be .introduced through the side or top of the conductor, and is maintained by gravity in conductive relation to the bottom wall of the latter. Where solid carbon dioxide is used, an insulating sleeve 258 is provided and also a suitable conductor resistance 259 separating the refrigerant from the conductor upon which it rests. Means is provided in the form of a duct 260 for permitting escape of the sublimed gases. An application of this unit is illustrated in Fig. 49, which shows in horizontal section a four-compartment car or truck, each compartment being provided with one of the aforedescribed units preferably suspended adjacent the top and at one side of the compartment.

l. The method of refrigerating by means of a solid refrigerant, which consists in providing between the refrigerant and the region to be refrigerated a principal path of heat transfer in the form of a thermal conductor capable of effecting a transfer of heat from said.l region to the refrigerant at a rate higher than that required for a given effective refrigerating temperature, and interposing between said conductor and the refrigerant a medium of thermal-transfer resistance to thereby control and regulate the rate of heat exchange between the refrigerant and the conductor.

2. The method of refrigerating by means of a solid refrigerant, which consists in providing between the refrigerant and the region to be refrigerated a principal path of heat transfer in lthe form of a thermal conductor capable of effecting a transfer of heat from said region to the refrigerant at a rate higher than that required for a given effective refrigerating temperature, and interposingbetween said conductor` and the refrigerant a medium of thermal-transfer resistance whereby the rate of heat exchange between the conductor and the refrigerant is restricted.

3. The method ,of refrigerating by means of a solid refrigerant, which consists-in providing between the refrigerantand the region to be refrigerated a principal path of heat transfer in the form of a thermal conductor capable of effecting a transfer of heat from said region to the refrigerant at a rate higher than that required for a given effective refrigerating temperature, and interposing in said path a mediumv of thermal-transfer resistance to thereby control and regulate the rate of heat exchange between the refrigerant and the region to be refrigerated.

4. In a 'refrigerating process' the method which consists in taking up heat from the refrigerated area or mass by relatively extended surfaces of a highly conductive metal, conducting this heat bymeans of the conductor to a relatively small surface of a solid refrigerant, and restricting theexchange of heat between the conductor and the refrigerant by means of a medium of thermal transfer resistance located between the conductor and the refrigerant.

5. A refrigerator chamber having therein a thick-Walled, gas-tight, cast-metal container Asubstantially without exterior insulation, and

having exterior metal surfaces exposed for heat labsorption and moisture deposit from the atmosphere of the refrigerated space, and means for supporting solid'carbon dioxidewithin the container in heat exchange relation but out of contact with the metal of said container.

6. Apparatus for refrigerating by the use of carbon-dioxide ice comprising a chamber, an insulating cabinet therein and` sealed therefrom and adapted for the reception of carbon-dioxide ice, a heat conductor having portions disposed interiorly and exteriorly of the cabinet, and vertical partitions within the cabinet subdividing the space therein into compartments, said conductor forming the bottoms of said compartments, and insulation removably superimposed upon said conductor without eliminating heat transfer between said conductor and the ice in said compartments.

'7. Apparatus for refrigerating by the use of carbon dioxide ice comprising .a chamber, an

insulating cabinet therein and sealed therefrom and adapted for the reception of carbon dioxidel ice, a heat conductor having portions disposed interiorly and exteriorly of the cabinet, said conductor forming the bottom of the ice containing space in said cabinet, andinsulation removably superimposed upon said conductor Without eliminating heat transfer between said conductor and the ice vin said cabinet.

8. Apparatus for refrigerating by the use of carbon-dioxide ice comprising a chamber, an insulating cabinet therein and sealed therefrom and adapted for the reception of carbondioxide ice, a heat lconductor plate having portions disposed interiorly and exteriorly of the cabinet, insulation removably superimposed upon said plate and reducing without eliminating heat transfer between said plate and the ice in said cabinet, and an insulating wall coacting with the cabinet to produce a convection channel for the chamber in which the exteriorly-disposed portions of the plate extend.

9. Apparatus for refrigerating by the use of carbon-dioxide ice comprising a chamber, an insulating cabinet therein and sealed therefrom and adapted for the reception of carbon-dioxide ice, a heat' conductor plate having portions disposed interiorly and exteriorly of the cabinet, said plate forming the bottom of the ice containing space in said cabinet, insulation removably superimposed upon said plate and reducing without eliminating heat transfer between said plate and the ice in said cabinet, said plate dividing the cabinet into two sections, and separate access doors for said sections.

10. Apparatus for refrigerating by the use of carbon-dioxide ice comprising a chamber, an insulating cabinet therein and sealed therefrom and adapted for the reception of carbon-dioxide ice, a heat conductor plate having portions disposed interiorly and exteriorly of the cabinet, said plateforming the bottom of the ice containing space in said cabinet, insulation removably superimposed upon said plate and reducing without eliminating heat transfer between said plate and the ice in said cabinet, and thermostatically-controlled valve means regulating contact of convection currents in the chamber with the exteriorly-disposed portions of said plate.

11'. Apparatus for refrigerating by the use of carbon-dioxide ice comprising achamber, an insulating cabinet therein and sealed therefrom and adapted for the reception of carbondioxide ice, a heat conductor plate vhaving portions disposed interiorly and exteriorly of the cabinet, said plate forming the bottom of the ice containing space in said cabinet, insulation removably superimposed upon said plate and reducing without eliminating heat transfer between said plate and the ice in said cabinet, said exteriorly-disposed portions including vanes extending upwardly along the walls of the cabinet.

12. Apparatus for refrigerating by the use of carbon-dioxide ice comprising a chamber, an insulating cabinet therein and sealed therefrom and adapted for the reception of carbon-dioxide ice, a heat conductor plate having portions disposed interiorly and exteriorly of the cabinet, said plate forming the bottom of the ice containing space in said cabinet, insulation removably superimposed upon said plate and reducing without eliminating heat transfer between said plate and the ice in said cabinet, and thermostatically-controlled valve means regulating contact of convection currents in the chamber with the exteriorly-disposed portions of said plate, said exteriorly-disposed portions including vanes extending upwardly along the walls of the cabinet.

13. Apparatus for refrigerating by the use of carbon-dioxide ice comprising a storage chamber, an insulated cabinet therein and sealed therefrom, a heat conductor having portions disposed interiorly and exteriorly of the. cabinet, said cabinet adapted to simultaneously receive a plurality of bodies of ice, and means partially insulating certain of the bodies from the conductor.

1 4. Apparatus for refrigerating by the use of carbon-dioxide ice comprising a storage chamber, an insulated cabinet therein and sealed therefrom, a heat conductor having portions disposed interiorly and exteriorly of the cabinet, said cabinet adapted to simultaneously receive a plurality of bodies of ice, means partially insulating certain of the bodies from the conductor, said conductor subdividing the interior of the cabinet into two compartments, and separate access doors for said compartments. i

15. Apparatus for refrigerating by the use of carbon-dioxide ice comprising a storage chamber, an insulated. cabinet therein and sealed therefrom and adapted for the reception of car-- bon-dioxide ice, a heat conductor having portions disposed interiorly and exteriorly of the cabinet, and means partially insulating the ice from the conductor.

16. Apparatus for refrigerating by the use of carbon-dioxide ice comprising a storage cham- 5 ber, an insulated cabinet therein and sealed therefrom and adapted for the reception of carbon-dioxide ice, a heat conductor having portions disposed interiorly and exteriorly of the cabinet, means partially insulating the ice from the conductor, said conductor subdividing the interior of the cabinet into two compartments, and separate access doors for said compartments.

17. Refrigerating apparatus comprising a thermal conductor in the form of a container, an insulating casing for said container, said conductor having throughout a conductive capacity capable of maintaining in all parts of the contained space a substantially uniform refrigerating temperature by means of a solid refrigerant in conductive 2O association with that portion of the conductor forming the bottom of the container, means in said container for supporting a product above said refrigerant, and means located between the r refrigerant and the conductor for regulating and 25 controlling said conductive association.

18. Apparatus for refrigerating by means of/ solid'carbon dioxide ice, which comprises a. thermal conductor in the form ofa container, an insulating casing surrounding said container, an 30 insulating jacket in the bottom of said container enclosing the said refrigerant and extending between the refrigerant and the said conductor,

`said conductor having throughout a conductive ductor in the form of a container, an insulating casing surrounding said conductor, and a refrigerant-receiving jacket in the bottom of said container extending between the refrigerant and the said conductor whereby the conductive relation. between the refrigerant and the said conductor is regulated, and said conductor having a conductive capacity throughout insuring maintenance of all parts'of the interior space of said container at a substantially uniform predetermined refrigerated temperature.

20. In a refrigerator for use withsolid carbon dioxide, a receptacle for said refrigerant in the form of a thermal conductor having a plurality of walls, each of said walls being associated with a segregated portion of the interior of said refrigerator, and means for conductively associat- `ing the said refrigerant with at least one of said lsaid refrigerant, 'and variable insulation means for regulating the conductive relation between the said refrigerant and those portions of the conductor directly associated with the dierent compaxjtments. I 75