US2033554A - Refrigerating apparatus - Google Patents

Description

\ March 10, 1936. H. F. SMITH REFRIGERATING APPARATUS Original Filed Jan. 29, 1932 2 Sheets-Sheet l March 10, 1936. H F, SMH-H 2,033,554

REFRIGERATING APPARATUS Original FiledJan. 29, 1932 2 Sheets-Sheet 2 Patented Mar. l0, 1936 PATENT OFFICE REFRIGERATING APPARATUS Harry F. Smith, Dayton, Ohio, assignor, by mesne assignments, to General Motors Corporation, al corporation of Delaware Application January 29, 1932, sei-iai No. 589,616 Renewed June 26, 1983 19 claims. (cica-711.6)

This invention relates to refrigerating apparatus and more particularly to refrigerating ap- Daratus utilizing a plurality oi refrigerant circuits.

Ihe object of the present invention is to provide an improved refrigerating apparatus which prevents dehydration of food by the uniform cooling of a food storage compartment at a relative highv refrigerating temperature and which at the same time provides a freezing compartment maintained at a relatively low temperature.

Another object of the present invention is to provide means whereby a chamber of arefrigerator cabinet, cooled by an evaporator of a refrigerating system, can be divided into two or more compartments at will and which compartments will be efficiently maintained at different constant temperatures.

Another object of the present invention is to provide means whereby the foregoing objects can be accomplished in cabinets now in use without altering the construction thereof.

In carrying out the foregoing objects it is a further object to enable the accomplishment of having a wide variation of temperatures between a freezing and a food storage compartment.

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 formo the present invention is clearly shown.

In the drawings:

Fig. 1 isav front vview of a refrigerator cabinet having my improved refrigerating apparatus 1ocated therein and having the refrigerant liquefying unit `of the primary refrigerating circuit shown diagrammatically; y

Fig. 2 is lan enlarged vertical sectional view of my improved refrigerator cabinet;

Fig. 3 is a vhorizontal sectional view of the cabinet shown in Fig. -1 and taken on the line 3--3 of Fig. 2 showingthe cabinet door in closed position;

Fig. 4 is a sectional view taken on the line 4-4 of Fig. 3 showing a sealing member secured to they cabinet door; y 4

Fig. 5 is a front viewof a refrigerator cabinet of the commercial type having a refrigerating apparatus constructed according to the present` net shown in Fig. 6 and taken on the line 1-1 thereof.

For the purpose of illustrating my invention I have shown in the drawings a refrigerator cabinet of the household type and also a refrigerator cabinet of the commercial type adapted for installation in small stores or the like. The desirability of having a low temperature or freezing compartment and a compartment maintained at a relatively higher temperature in such refrigw erator cabinets occurs almost daily because of the increasing sales of frozen meats or the like together with the sale of other commodities usually stored or maintained at a relatively higher temperature until being dispensed -by the retailer or consumed by the purchaser. Therefore, myr invention is particularly directed to a method of and an apparatus for dividing a refrigerating chamber, normally entirely maintainedlat a sub'. stantially uniform temperature, of a refrigerator cabinet into two or more compartments at will to afford a low temperature or freezing compartment maintained, for example, at 10 Fahrenheit and a 'compartment maintained at a relatively higher temperature such, for example, as 40 Fahrenheit.

Referring tothe drawings the numeral 20 designates a refrigerator cabinet'of the household type having a cooling chamber divided into two differently refrigerated compartments. According to the present invention the cabinet 2D normally comprises a chamber `formed by the lining 2| and having an evaporator or cooling unit 22 disposed therein usuallyin .the upper portion of the chamber; The evaporator 22 'is adapted to 35 be connected teeny-suitable type refrigerant liquefying unit which unit V,isusually located in a compartment 23l disposed belowA the chamber formed by the lining 2l of cabinet 20. However, this unit .may be located,vif desired, in the basement of the building housing: the cabinet 20. The refrigerant liquefying unit is shown diagrammatically in the present disclosure and includes the compressor 25 Vwhich compresses refrigerant contained in the system and forwards it to a condenser 26 where it. is cooled and liqueed in any suitable 'manner .and flows into a liquid refrigerant storage tank` or receiver 21. The evaporator 22 is connected by the conduit 28 with the receiver 21 andreceives liquid re- 50 frigerant therefrom. Liquidrefrigerant in the evaporator 22 upon absorbing heat, from the medium to be or being cooled' by the evaporator, vaporizes andis pumped back to the crankcase of compressor 25 through the conduit 29. Com- 55 pressor may be operated by any suitable means such as by being connected to an electric motor through belt and pulley connections 3|, 32 and 33 respectively. Operations of the motor 30 and consequently compressor 25 may be controlled in any suitable manner. For example, I have shown a control switch 35 actuated, in response to pressures existing in the low pressure conduit 29, by a bellows 36 connected to the conduit 29 by pipe 3l. Movement of switch 35 by bellows 36 actuates a snap mechanism to move a contact 38 relative to a contact 39 to make or break the electric circuit to motor 30 for starting or stopping operation of the compressor 25.

The evaporator or cooling unit 22 may be of the type disclosed in the patent to R. G. Osborn 1,556,708, issued October 13, 1925, and may include depending refrigerant expansion ducts, loops forming a freezing chamber or compartment therebetween and havingice making receptacles supported thereby for receiving ice trays containing substances to be frozen. 'I'he control switch 35 may be of the type disclosed in the patent to Otto M. Summers 1,819,979, August 18, 1931, which switch includes means for modifying the action of the refrigerant liquefying unit to produce a modifying temperature of the evaporator 22. The evaporator 22 produces a refrigerating effect for normally cooling the entire chamber of the cabinet 20 to a substantially uniform temperature to preserve food products stored on shelves located at various places in the chamber. This normal cooling effect of the evaporator 22 or the temperature within the chamber is unsuitable for preserving a wide varlety of food products. For instance, the user may have purchased a large supply of frozen meats,.berries or the like which must be maintained at a very low temperature in order to prevent thawing thereof, together with other food products which should be maintained at a relatively higher temperature in order to prevent dehydration thereof. Therefore my invention is directed to the provision of one or more compartments in the chamber of a refrigerator cabinet and means for maintaining one of said compartments at a very low temperature while at the same time maintaining the other of said compartments at a relatively high uniform temperature in order to provide for the proper cooling and storing of a wide variety of food products.

In order to accomplish the results to which my invention is directed I have provided means for ividing the chamber, of the refrigerator cabinet formed by the lining 2|, into two compartments 4| and 42. This means comprises a hollow member or a substantially fiat hollow plate 43 (see Fig. 2) comprising a top wall 44, a bottom wall and end walls 46. The member 43 may be formed oi' any suitable material of high heat conductivity such, for example, as aluminum or copper and its construction may also be of any suitable form. Member 43 is hermetically sealed and contains therein a refrigerating medium to be more fully discussed hereinafter. In order to insure against bursting or deformation of the hollow member 43 I interpose studs or bars between the walls 44 and 45 of the member 43. These bars or studs 41 are preferably made of a suitable insulating material and may be securely fastened to the walls 44 and 45 in any suitable manner. 'I'he hollow plate or member 43 may be installed in the cabinet 20 by inserting same into the door opening, which opening is closed by a door 5| and provides access to the chamber formed by the lining 2|, and supporting same on shelf supports located in the chamber after a shelf has been removed therefrom. This member may, if desired, be placed above a shelf and supported thereon thus eliminating the necessity of removing a shelf from the cabinet. In either event the hollow plate or member 43 is of such size that three of the end walls 45 thereof snugly fit against the cabinet lining 2| in order to block or prevent the circulation of air between compartments 4| and 42. To block or prevent such circulation of air at the front ci the chamber formed by lining 2| I provide a gasket or scaling member 53 which may be constructed of any suitable soft insulating material, such as rubber or the like, and which may be secured in any suitable manner to the door 5| (see Fig. 4). For example, gasket 53 may be disposed in a cut-away portion of the insulation of door 5| and secured in this position by the edges of the inner lining of the door. It is apparent from Fig. 4 of the drawings that gasket 53 will be compressed by its engagement with the member 43, when the door 5| is closed, thus sealing compartments 4| and 42 from each other at the front of the hollow plate or member 43.

In Figs. 5, 6 and 7 of the drawings I have shown a refrigerator cabinet of the commercial or showcase type having my invention embodied therein.

This cabinet is of the type suitable for installation in small stores or the like and is adapted to be located upon a counter 55 of such stores. Access to the interior of cabinet 55 is provided by a door 51 in the back of cabinet 55. The front wall of cabinet 55 may be provided with a plurality of glass panels or windows 53 so that food products contained in the cabinet may be displayed to prospective purchasers. It is to be understood that other parts or elements of the cabinet 55 are similar to parts of the cabinet 20 disclosed in Figs. i, 2, 3 and 4 and are designated by like reference characters, even though these parts may be of a different form or size.

Preferably a volatile liquid refrigerant is sealed within the member 43 such as a halogen derivative of an aliphatic hydrocarbon and for instance difiuorodichloromethane. It is apparent that the refrigerant circuit heretofore described and illustrated in Fig. 1 forms a primary refrigerating system of my apparatus which uniformly cools the entire refrigerating chamber, formed by the lining 2| of cabinet 23, to a predetermined low temperature. It is also apparent that. by the sealing of refrigerant in the hollow flat plate or member 43, this member forms a secondary refrigerating system. When member 43 is placed in the cabinet 2|) to divide the cabinet into the compartments 4| and 42 the secondary refrigerating system formed thereby will be rendered effective for cooling the lower compartment 42 and consequently food products stored therein. Upper compartment 4| is adapted to be maintained at a low temperature such, for example. as 10 Fahrenheit for properly refrigerating or preserving frozen food products stored therein. Through the action of the secondary refrigerating system, formed by the hollow fiat plate or member 43, compartment 42 will be maintained at a relatively higher temperature than compartment 4| for refrigerating or preserving food products not desired to be maintained at a very low temperature because of the likelihood of these foods being dehydrated by such low temperatures. In order to control the temperature differential between compartments 4| and 42 a quantity of gas such as air, non-condensible at temperatures prevailing in the secondary refrigerating system. may be injected into the said secondary refrigerating system, Thus it is to be understood that a wide variation of temperatures can be had between compartments 4I and 42.

The operation of my refrigerating apparatus to cool compartments 4I and 42 at differenttemperatures will now be explained. Compartment 4I is maintained at a low or freezing temperature by the cooling effect produced by the evaporator 22 through the action or operation of the refrigerant liquefying unit for freezing substances in the cooling unitv 22 and for preventing thawing of frozen products placed in the compartment 4i for storage. Compartment 42 and food products placed therein for storage will be maintained at a predetermined relatively higher temperature by the use of the secondary refrigerating system formed by the hollow flat plate or member 43. Upon an increase in temperature within compartment 42 above a predetermined limit,

accordingto the character of the charge kof reg -irigerant or gas in member 43, liquid refrigerant lying in contact with the bottom wall 45 or member 43 Will absorb this heat and will vaporize.

This vaporized refrigerant rises and comes in contact with'the cold top wall 44 of member 43 and gives vup its heat to this wall. The vaporized refrigerant. is therefore condensed and flows 'or drops back into the body of "liquid refrigerantr` containeddn the hollow plate or memberv 43,91" Heat dissipated by the secondary refrigerating', system to the top wall 44 of member 43 is abi" sorbed by the evaporator 22 of the primary rev frigerating system and is extracted from the compartment 4|. Thus the secondary refrigerating system maintains the temperaturel within the compartment 42 at a predetermined uniform temperature in Yaccordance with the character of the charge of refrigerant in'the member 43 to obtain the desired temperature differential between compartments 4i and 42.

From the foregoing it is apparent that I have provided an improved refrigerating apparatus, inf cluding a Vcabinet and provisions whereby the cabinet maybe altered at will to provide two compartments' therein maintained at different uniform temperatures, so that a large variety of food -products may be stored in the cabinet without causing dehydration of certain of the food products. It is also apparent that my apparatus is capable of obtaining a wide temperature variation between the freezing compartment provided therein and the food compartment maintained at a relative higher temperature.

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

What is claimed is as follows:

1. Refrigerating apparatus comprising in combination; a cabinet, means dividing the interior of said cabinet into a plurality of compartments, a primary refrigerating system including a refrigerant lquefying unit and a refrigerant evaporatingv element, said evaporating element being disposed in one of saidcompartments and adapted to maintain said compartment at` a predetermined low temperature, said dividing means comprising a hollow member having a refrigerating medium sealed therein for providing a-secondary refrigerating system, s aidfemember having one of its walls in thermal association with the compartment cooled by the evaporating element of the primary system and having another wall thereof in thermal association with the other of said compartments whereby said secondary refrigerating system is rendered effect-ive to maintain said other compartment at a predetermined higher temperature.

2. Refrigerating apparatus comprising in com ,.1

bination, a cabinet, means dividing the interior of said cabinet into a plurality of compartments, a primary refrigerating system including a refrigerant liquefying unit and a refrigerant evaporating element, said evaporating element being disposed in one of said compartments and adapt-A ed to maintain said compartment at a predetermined low temperature, said dividing means comprising a hollow member having a refrigerating medium sealed therein'for providing a secondary refrigerating system, said secondary refrigerating system having therein a gas non-condensible at temperatures prevailing in the secondary system for maintaining a temperature differential with respect to the primary system, and said member having one of its walls in thermal association with the compartment cooled by the evaporating element of the primary system and having another wall thereof in thermal association with the other of said compartments whereby said secondary refrigerating system is ,rendered effective to maintain'said other compartment at a predetermined higher temperature.

` v3. ,Refrigerating apparatus comprising in combination, a cabinet, means dividing the interior of said cabinet into two compartments disposed kone above the other, av primary refrigerating system including a. refrigerant liquefying unit and a refrigerant evaporating element, said evaporating element being disposed in the upper of said compartments and adapted to maintain said upper compartment at a predetermined low temperature, said dividing means comprising a hollow member having. a refrigerating medium vsealed therein for providing a secondary refrigerating system, said member having one of its walls in thermal association with the compartment cooled'by the evaporating element of the primary system and having another wall thereof in thermal association'with the lower compartment whereby said secondary refrigerating sys- 'tem is rendered effective to maintain said lower compartment at a predetermined higher temperature.

4. Refrigerating apparatus comprising incombination, a cabinet,l means dividing the interior of said cabinet into two compartments disposed one above the other, a primary refrigerating system including a refrigerant liquefying unit and a refrigerant evaporating element, said evaporating element being disposed in the upper of said compartments and adapted to maintain said upper compartment at a predetermined low temperature, said dividing ans comprising a hollowl member having refrigerating medium sealed therein for providing a secondary refrigerating system, said secondary refrigerating sys- 1 tem having therein a gas non-condensible at temperatures prevailing in the secondary system for maintaining a temperature differential with respect to the primary system, and said member having one of vits walls in thermal association withY the compartment cooledvby the evaporating element of the primary system and having another .wall thereof. in thermal association with the lower compartment whereby said secondary refrigerating system is rendered effective to maintain said lower compartment at a predetermined higher temperature.

5. Refrigerating apparatus comprising in combination. a cabinet, removable means dividing the interior of said cabinet into a plurality of compartments, a primary refrigerating system including a refrigerant liquefying unit and a refrigerant evaporating element. said evaporating element being disposed in one of said compartments and adapted to maintain said compartment at a predetermined low temperature. said removable dividing means comprising a substantially dat hollow piate having a refrigerating medium sealed therein for providing a secondary refrigerating system. said plate having one of its walls in thermal association with the compartment cooled by the evaporating element of the prlmarysystemandhavinganotherwallthereof in thermal association with the other of said compartments whereby said secondary refrigeratlng system is rendered effective to maintain said other compartment at a predetermined higher temperature.

8. Refrlgerating apparatus comprising in combination, a cabinet, removable means dividing the interior of said cabinet into a plurality oi' compartments, a primary refrigerating system i including a refrigerant liquefying unit and a refrigerant evaporating element, said evaporating element being disposed in one of said compartments and adapted to maintain said compartment at a predetermined low temperature, said removable dividing means comprising a substantiaily fiat hollow plate having 'a refrigerating medium sealed therein for providing a secondary refrigerating system, said secondary refrigerating system having therein a gas non-condensible at temperatures prevailing in the secondary system for maintaining a temperature diii'erential with respect to the primary system. and said plate havingoneofitswallsinthermalassociation with the compartment cooled by the evaporating elementoftheprimarysystemandhavinganother wall thereof in thermal association with the other of said compartments whereby said secondary refrigerating system is rendered eilectivetomaintainsaidothercompartmentata predetermined higher temperature.

7. Refrigerating apparatus comprising in combination, a cabinet. removable means dividing the interior of said cabinet into two compartments disposed one above the other, a primary refrigerating system including a refrigerant llquefying unit and a refrigerant evaporating element, said evaporating element being disposed in the upper of said compartments and adapted to maintain said upper compartment at a predeterminedlow temperature, said removable dividing means comprising a substantially dat hollow plate having a refrigerating medium sealed therein for providing a secondary refrigerating system. said plate having one of its walls in thermal association with the compartment cooled by the evaporating element of the primary system and having another wall thereof in thermal association with the lower compartment whereby said secondary refrigerating system is rendered effective to maintain said lower compartment at a predetermined higher temperature. v

8. Refrigerating apparatus comprising in combination. a cabinet, removable means dividing the interior of said cabinet into twocompartments disposed one above the other. a primary rcfrigerating vsystem including a refrigerant -last named means liquefying unit and a refrigerant evaporating element. said evaporating element being disposed in the upper of said compartments and adapted to maintain said upper compartment at a predetermined low temperature. said removable dividing means comprising a substantially fiat hollow plate having a refrigerating medium sealed therein for providing a secondary refrigerating system, said secondary refrigerating system having therein a gas non-condensibie at temperatures prevailing in the secondary system for maintaining atemperature dierentlai with respect to the primary system, and said plate having one of its walls in thermal association with the compartment cooled by the evaporating eiement of the primary system and having another wall thereof in thermal association with the low' er compartment whereby said secondary refrigerating system is rendered effective to maintain said lower compartment at a predetermined higher temperature.

9. Refrigerating apparatus comprising in combination, a cabinet. means -dividing said cabinet into a plurality of compartments to be maintained at different temperatures relative to one another. means for refrigerating the low temperature compartment. a fluid heat transfer medium in said low temperature compartment. and means for cooling the other of said compartments, said last named means comprising asecondary .volatile refrigerant container forming at least a portion of said dividing means, the container transferring heat to said refrigerating means solely through said fluid medium.

l0. Refrigerating apparatus comprising combination, a disposed cabinet. means dividing said cabinet mio a plurality oi superto be maintained at diferating compartment, a duid heat transfer medium in said low temperature compartment, and means for cooling the other of said compartments. said comprising a secondary voiatile refrigerant container forming at least a solelly through. said fluid medium.

l Refrigerating apparatus comprising in combination. a cabinet, a hollow plate dividing said cabinet into a plurality of compartments to be maintained at diderent temperatures relative to one another. said hollow plate forming the bottom wall of one of said compartments. and forming the top wall of the other of said compartments. a iiuid heat transfer medium in said low temperature compartment. and a volatile refrigerant sealed within said hollow plate and forming a refrigerant circuit for cooling the other of said compartments, said plate transferring heat to said refrigerating means solely through said fluid-medium.

12. Refrigerating apparatus comprising in combination. a cabinet, a hollow plate dividing said plate into s plurality of compartments to be maintained at diiierent temperatures relative to one another, a volatile refrigerant sealed within said hollow plate, means for refrigerating the low temperaturelcompartment. a fluid heat transfer' medium in said low temperature compartsaid hollow plate forming the top wall of the other of said compartments and also forming the evaporating surface for said volatile refrigerant, said plate transferring heat to said refrigerating meanssolely through said fluid medium.

13. Refrigerating apparatus comprising in combination, a cabinet, means dividing said cabinet into an upper food storage compartment and a lower food storage compartment to be maintained at different temperatures relative to one another, means for refrigerating the low temperature compartment, means for maintaining said second named means between substantially constant predetermined temperature limits, and means for cooling the other of said compartments, said last named means comprising a secondary volatile refrigerant circuit forming at least a portion of said dividing means.

14. Refrigerating apparatus comprising in combination, a cabinet, means dividing said cabinet into an upper food storage compartment and a lower food storage compartment to be maintained at different temperatures relative to one another, means for refrigerating the upper of said food storage compartments to a predetermined low temperature, means for maintaining said second named means between substantially constant temperature limits, and means for cooling the lower of said food storage compartments.' said last named means comprising alfsecondary? volatile refrigerant circuit formingat' leastga;

portion of said' dividing means'. i..

15. A 'refrigerating apparatuscomprising in combination, a cabinet having a plurality of ver? tically and horizontally disposed stationary insulated walls defining a chamber therein, said chamber extending continuously from one horizontal insulated wall to another thereof and from one vertical insulated wall to others thereof, a thermally conductive partition dividing said chamber into an upper compartment and a lower compartment and substantially isolating said compartments from air circulation therebetween, an evaporator of a closed refrigerant circulating system disposed in one of said compartments and exposed to the air therein for cooling and causing circulation of the air, said evaporator being arranged withln said compartment to provide a food storage space on at least one side thereof, a door opening and a single door cooperating therewith and providing access to both of said compartments, and sealing means cooperating with said door and with said partition when the door is in closed position for preventing air circulation between said compartments adjacent the partition.

16. A refrigerating apparatus comprising in combination, a cabinet having a plurality of vertically and horizontally disposed stationary insulated walls defining a chamber therein, said chamber extending continuously from one horizontal insulated wall to another thereof and from one vertical insulated wall to others thereof, a thermally conductive partition dividing said chamber into an upper compartment and a lower compartment and substantially isolating said compartments from air circulation therebetween, an-evaporator of a closed refrigerant circulating system disposed in one of said compartments and exposed to the air therein for cooling and causing circulation of the air, said evaporator being arranged within said compartment to provide a food storage space on at least one side thereof, a door opening and a single door cooperating therewith and providing accem to both of said compartments, sealing means cooperating with said door and with said partition when the door is in closedl position for preventing air circulation between said compartments adjacent the partition, and said partition being removable from said chamber horizontally throughsaid dooropening.

17. A refrigerating apparatus comprising in combination, a cabinet having a plurality of vertically and horizontally disposed stationary insulated walls Idefining a chamber therein, said chamber extending continuously from one horizontal insulated wall to another thereof and from one vertical insulated wall to others thereof, a thermally; conductive partition dividing said chamber into an upper compartment and a lower compartment and substantially isolating said compartments from air circulation therebetween, an evaporator of a closed refrigerant circulating system disposed in the upper of said compartments and exposed to the air therein for cooling and causing circulation of the air, said evaporator being arranged vwithin said upper compartment to provide a food storage space on at least one side thereof, a door opening and a single door cooperating therewith and providing access to both the upper and lower compartments, and sealing means cooperating with said door and with said partition when the door is in closed position for preventing air circulation between Vsaid compartments adjacent the partition.

,l 18. A" nefrigeratingy apparatus comprising in' combination, a cabinet 'having a pluralityof vertically and horizontally disposed stationary in sulated `walls defining a chamber therein, said chamber extending continuously from one horizontal insulated wall to another thereof and from one vertical insulated wall to others thereof, a thermally conductive partition dividing said chamber into an upper compartment and a lower compartment and substantially isolating said compartments from air circulation therebetween, an evaporator of a closed refrigerant circulating system disposed in the upper of said compartments and exposed to the air therein for cooling and causing circulation of the air, said evaporator being arranged Vwithin said upper compartment to provide a food storage space on at least one side thereof, a door opening and a single door cooperating therewith and providing access to both the upper and lower compartments, sealing means cooperating with said door and with said partition when the door is in closed position for preventing air circulation between said compartments adjacent the partition, and said partition being removable from said chamber horizontally through said door opening.

19. A refrigerating apparatus comprising in combination, a cabinet having a plurality of vertically and horizontally disposed stationary insulatedwalls defining a chamber therein, said chamber extending continuously from one horizontal insulated wall to another thereof and from one vertical `insulated wall to others thereof, a thermally conductive partition extending entirely across said chamber to divide the chamber into an upper compartment and a lower compartment and to isolate said compartments from air circulation therebetween, an evaporator of a closed refrigerant circulating system disposed in the upper of said compartments and exposed to the air therein for cooling and causing circulation of the air, said evaporator forming a freezing compartment within said upper compartment and also being arranged within said pper compartment to provide a food storage space on at least one aide thereof. a door opening anda single door cooperating therewith and providing accesa to both ot said compartments, sealing means cooperating with laid door and with said partition when the door ia in closed position for preventing air circulation between said-compartments adjacent the partition, and laid partition being removable from said chamber horiaontaliy through aaid door opening.

HARRY l". SMITH.

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