US2065537A - Refrigerating apparatus - Google Patents

Description

De.29, lesa L. A. PHlLiPP f 2,065,531-

REFRIGERATING APPARATUS original Filed Feb. 27, 193:5

INVENTOR. Lewes/wi: l?. PML/PP BY 4 W 2 M ATTORNEY.

Patented Dec. l2li), 1936 REFRIGERATING APPARATUS Lawrence A. Philipp, Detroit, Mich., assigner to Kelvinator Corporation, Detroit, Mich., a corporation of Michigan Application February 27, 1933, Serial No.

' Renewed July 15, 1936 1': claims. (ci. s2-12s) 'Ihis `invention relates -to refrigerating apparatus, and more particularly to refrigerating apparatus of the household type.

One of the objects of my invention is to provide a new and improved arrangement for freezing substances and for cooling circulating air in a refrigerator cabinet.

Another object of my invention is to provide within a refrigerator cabinet refrigerantevaporating means which is arranged and operated without the collection vof frost thereon or a slight film of frost is allowed to collect thereon during the ori-phase of the refrigerating cycle and is melted oil' during the off-phase of the refrig- -erating cycle while at 'the same time provisions are made for freezing substances, such as ice cubes and the like, and for cooling circulating air in the food storage compartment of the cabinet whereby continuous refrigeration at substantially constant predetermined temperatures is assured and the necessity of periodic inoperative conditions of the system for defrosting is avoided.

Another object of my invention is to provide a new and improved refrigerant evaporator for cooling circulating air in a food storage compartment of a refrigerator cabinet.

Other objects and advantages of the present invention will readily be apparent from the following description and by referring to the Vaccompanying drawing. i

In the drawing:

Fig. 1 is a front view in elevation of a refrigerating apparatus embodying features of 'my invention;

Fig. 2 is a fragmentary, vertical view in cross section of the heat. absorbngmeans embodyingfeatures of my invention;

Fig. 3 is a side view in elevation of ther'elaf" tively small heat capacity refrigerant evaporator forming part of the heat absorbing means;

Fig; 4 is a top plan view in elevation of the heat absorbing means;

Fig. 5 is a fragmentaryA View-in cross section and partly in elevation of a modied form of heat absorbing means; and

Fig. 6 is a View taken along the lin'e 6-6 of .Fig 5.

Referring to the drawing, the numeral 2ll'des1 ignates, in general, a refrigerator cabinet having a food storage compartment 2l. Within the food storage compartment there is disposed heat absorbing means designated, in general, by the numeral 23. A refrigerant Acondensing element 25 is operatively connected to the heat absorbing means 23 by means of a liquid supply conduit 26` and a. vapor return conduit 21. The condensing element 25 may be located at any convenient place either within the cabinet or remote therefrom.

Referring more particularly lto Figs. 2,.3 and 4, theheat absorbing means 23 comprises, in general, a refrigerant evaporator 3D which is of relatively small heat capacity and which has a large areaexposed to the circulating air within the food storage com- 10 partment 2l. The evaporator 30 comprisesfin general, an outer metallic shell 32 which is of box-like construction and is provided with an open top which is secured to the top insulating wall33 of the food storage compartment by 15 brackets 34 to prevent the admission of circulating air in the food ,compartment into the interior of the shell 32. The shell 32 includes Vertical in detail to the drawing, 'and 5` lside walls- 35, bottom wall 31, rear wall 38 4and a front wall 40.l The front wall 4U is provided 2D with openings 42 of sufficient size for receiving ice making receptacles 45. If desired, `the closure member or rear wall 38 may be omitted and the shell 32 disposed in thefood storage compartment 2| adjacent the rear wall thereof to 2'5 prevent circulation of 4air from the food storage compartment into the interior. of the shell 32. The evaporator 30 also includes a pair of embossed sheetmetal plates 41, one of each. being secured to side walls 35 to provide spaces 48 and 30 49 for refrigerant. Preferably, the embossed plates 41 are formed to provide serpentine-like passageways for refrigerant between its inner wall and'theshell 32. The refrigerant spaces 48 and 49 between the plates 41 and the sheet metal 35 shell 32 are inter-connected by means of a refrigerant conduit 50 which inter-connects said spaces adjacent the lower parts thereof. Liquid refrigerant is supplied to the refrigerant spaces from the liquid supply conduit 26', first into space 40 48 whence it passes through conduit 50 into the refrigerant space 49. In order' to increase the' heat transferV characteristics of the evaporator 30,

I have provided a plurality of U-shaped heat ab- These fins are vertically dis- 45 posed in parallel relation on each side of the evaporator adjacent thel refrigerant spaces V48 and`49. Preferably, the flns are welded to the shell 32.

VThe heat absorbing meansv 23' also includes a 50 relatively large heat capacity refrigerant evaporator or low temperature evaporator which is disposed entirely within the confines of the relativelysmall heat capacity evaporator 30 so that its exposed surfaces will be exposed to substan- 55 'absorbing means.

tially non-circulating air. This arrangement either substantially or entirely avoids the necessity of periodically defrosting the4 low temperature evaporator 55. The low temperature evaporator 55 includes an outer sheet metal shell 51 and an inner sheet metal shell 5 8 suitably secured together as by welding adjacent their edges and at various contacting points between the edges. These shells are formed substantially in the shape of a U and the outer shell being corrugated as at 8| to provide spaces for the passage of refrigerant, between said shells. The inner shell is provided with a pair of arcuate portions 82 adjacent the upper opposite extremities thereof toprovide refrigerant headers 83 for liquid and gaseous refrigerant. The headers 83 are inter-v connected by means of conduit 84 to which the vapor return conduit 21 is connected. Liquid refrigerant is delivered to the low temperature evaporator 55 through a conduit 81 which is connected to the outlet end of the relatively small heat capacity evaporator 30. Both liquid and gaseous refrigerant passes from the evaporator 30 through conduit 81 into the low temperature evaporator 55. The gaseous refrigerant is withdrawn l'from the headers 83 and. conduit 84 through the vapor conduit 21. Suitable shelves 1| are provided within the ice freezing. zone 13 of evaporator 55 to support the ice trays 45.

The refrigerant condensing element comprises, in general, a compressor 10, motor 12 for operating the compressor, condenser 14, and a high side float mechanism 15. The compressor withdraws evaporated refrigerant from the heat absorbing means through conduit 21, compresses the gaseous refrigerant and delivers it to the condenser wherein it is liquefied and from which it is delivered to the high side float mechanism. Liquid refrigerant is supplied to the heat absorbing means through conduit 28 under the control of float mechanism 15.- Preferably, the condensing element is intermittently operated for maintaining substantially constant predetermined temperatures in the heat In) order to control the operation of the condensing element', I have provided an automatic switch 80 which is actuated by expansible bellows B2 and a thermostatic uid containing bulb 85 in response to changes in temperatures in the relatively small heat capacity evaporator 30 for connecting and disconnecting the motor to and from the power mains 81. Preferably, the bulb` 85 is soldered ,to a side wall of the evaporator 30 adjacent the refrigerant space 43. From the foregoing, it will be noted that the low temperature evaporator 55 is disposed within the confines of the evaporator 80 which is sealed to a wall of thefood storage compartment. Un-

der these conditions, none of the exposed surfaces` 'are arranged 4so that the circulating air in the food compartment willcontact therewith. Only the substantially, non-circulating air within shell 1 32 can contact with the low temperature evaporator. Thus, ,it is unnecessary to temporarily interrupt the normal cyclic operation of the condensing-element to defrost the low temperature evaporator as the accumulation of frost thereon is unlikely. Thus, insofar as the low temperature' evaporator isl concerned, continuous 4refrigeratiorf' of a substantially constant predetermined value is assured.

In' order to avoid/ the necessity of interrupt-I ving the-refrigerating effect ofthe relatively small heat capacity evaporator, I have arranged the thermostaacauy controlled switch an so that the condensing element is operated in such a manner that the demand for refrigeration by the evapoon its exposed surfacesdue to the deposit of moisture from the circulating air. If desired, the switch may be set so that only a slight film of frost collects thereon during the on-phase of the refrigerating cycle and is melted off during the olf-phase ofthe refrigerating cycle. B'y providng a relatively small heat capacity refrigerant evaporator whlc has a large area exposed to the circulating air, it may be operated under these conditions and maintain proper temperatures within the food compartment for the preservation of foods stored therein. Thus, continuous refrigeration of a substantially constant, predetermined value in the evaporator 30 is assured. In an apparatus of the type hereinbefore described, the moisture contained in the circulating air is deposited on the walls of the evaporator and whether the evaporator is permitted to ac cmulate a slight film of frost between cycles or whether it operates so that no frost forms thereon the temperature is low enough to accumulate moisture on the side walls adjacent the spaces 48 and 48 and on fins 5|. In order to carry off the drip water received from the fins 5| and sides 35 of evaporator 30, I have provided troughs immediately below the fins 5| and at the lowermost parts of side walls 35. Preferably, the troughs 90 are formed integrally with a sheet metal member 92 which serves to clamp a slab of insulation 94 to the ,bottom Wall/ 31 of the evaporator 30. This insulation prevents the deposit of moisture on the lowermost -part of the evaporator 30. Thus, it will be noted that the drip water from the side walls is taken care of by troughs 90, and it will also be noticed that moisture is not de posited on the bottom wall of the relatively small heat capacity evaporator. If desired, the troughs 80 may be interconnected by a conduit (not shown) which may be used for carrying olf the drip water to a suitable drain.

Referring now to Figs. 5 and 6, there is shown a modified form'of heat absorbing means whichcom'prises, in general, a relatively small heat capacity evaporator |00, which is constructed in all respects like evaporator 30 and is operated under plied to evaporator |00 through conduit |28, and

evaporated refrigerant is withdrawn from the up- 'permost plate evaporator |05 through conduit |21. Conduits '|28 and |21 correspond to conduits 28 and 21 and may be connected to the condensing element 25 in a like manner as conduits 28 and 21 are connected thereto. The plates 05 are adapted for supporting ice trays and provide means for rapidly freezing the water in the trays.

From the foregoing, it will be apparent that I have provided refrigerantv evaporating means which I have arranged in V,such a manner that itoperates without the collection of frost thereon or with a slight illm of frost collecting thereon only between cycles, while at the same time provisions are made for freezing substances, such as ice cubes and the like, and for cooling circulating air in the food storage compartment of the cabinet whereby continuous refrigeration at substantially constant predetermined temperatures is assured and the necessity of periodic inoperative conditions of the system for defrosting is avoided. yInasmuch as the formation of a blanket of frost or ice onk the surfaces of an evaporator` acts as an insulating medium to the transfer of heat, it will also be apparent from the foregoing that the system described herein operates at maximum emciency and continuous refrigeration is furnished without interrupting the refrigerating effect of the heat absorbing means to free frost and ice therefrom.

Although onlya preferred form of the invention has been illustrated, and that form described in detail, it will be apparent to those skilled in the art that various modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims. i

What I claim as my invention is:

l. Refrigerating apparatus comprising, in combination, a cabinet having a food storage compartment, a refrigerant evaporating element disposed in said compartment for cooling circulating air therein, a second evaporating element for maintaining relatively low temperatures for freezing substances, said second evaporating element being shielded fromthe path of circulating air in the food storage compartment by said first named evaporating element to prevent the deposit of moisture on said low temperature evaporating element from the circulating air, an intermittently operating refrigerant condensing element associated with said evaporating elements for maintaining said evaporating elements substantially flooded with liquid refrigerant, and means directly associated with said first named evaporating element for controlling the operation of saidcondensing element, said means controlling the on and ofi phases of the Vrefrigerating cycle in such a manner that frost does not accumulate on the rst named evaporating element at least part of the time.

2. Refrigerating apparatus comprising a rela-l -evaporatoxs and means directly responsive to changes in temperaturein said first named evaporator for controlling said means.

3. Refrigerating apparatus comprising, in combination, a 'cabinet having a food storage compartment, a box-like refrigerant evaporating element having an open top secured to an insulated wall in said compartment, said evapo` rating element including an insulated bottom wall, a front'wall having an opening, means associated with each side wall to provide spaces for` refrigerant, closure means. for the rear of said element and a refrigerant conduit interconnectying said side walls, a refrigerant evaporating element disposed within the confines of said boxlike evaporating element arranged for receiving an ice making receptacle throughthe opening in the front wall 'of the box-like element, and means for supplying refrigerant to said elements.

4. A refrigerant evaporating element comprising a sheet metal shell including vertical walls and a bottom wall, one of said vertical walls having an opening of sufficient size to receive an ice making receptacle, an embossed sheet metal plate cooperating with one of said vertical walls to provide a space for refrigerant, a second embossed sheet metal plate cooperating with an opposite wall to provide an additional space for refrigerant, and a refrigerant conduit interconnecting said spaces adjacent the lower parts' thereof.

5. A refrigerant evaporating element comprising a sheet metal shell including vertical walls and a bottom wall, one of said vertical walls having an opening of suincient size to Areceive anice makingreceptacle, an` embossed sheet metal plate cooperating with one of said vertical walls t'o provide a space for refrigerant, a second embossed sheet metal plate cooperating with an opposite wall to provide an additional space for refrigerant, a refrigerant conduit interconnecting said spaces adjacent the lower parts thereof, and a relatively low temperature refrigerant evaporator disposed within said shell for freezing the contents of said receptacle.

6. A refrigerant evaporating element comprising a sheet metal shell including vertical walls and a bottomwall, one of said vertical walls having an opening of sufficient size to receive an ice making receptacle, an embossed sheet metal plate cooperating with one vof said vertical walls to provide a space for refrigerant, arsecond embossed sheet metal ,plate cooperating with an opposite wall to provide an additional space for refrigerant, a relatively low temperature refrigerant evaporator disposed Within said shell for freezing the contents of said receptacle, means for delivering liquid refrigerant to one of said spaces, a conduit interconnecting said spaces for delivering liquid refrigerant from said space toV the other, means for carrying off liquid and gaseous refrigerant to the low ytemperature evaporator, and means for withdrawing exaporated refrigerant from the low temperature evaporator.

'7. Refrigerating apparatus comprising, in combination, `a cabinet having a food storage element having an' open top secured to a wall of said compartment, said evaporating element including an insulated bottom wall, vertical walls, independent embossed plates cooperating only with the two oppositeside walls to provide spaces for-refrigerant, a refrigerant conduit interconnecting said spaces at the lower parts thereof, fins on said side walls adjacent said plates, and troughs associated with said elements for receiving moisture deposited from said fins.

8.l Refrigerating apparatus comprising a refrigerant evaporator adaptedto be positioned in a cabinet for cooling circulating air therein and having a relatively large area exposed to the circulating air in the cabinet, a refrigerant evaporator disposed within the confines of the first named evaporator so as to be shielded from said l circulating air, a liquid refrigerant conduit .in-

terconnecting said evaporators for conducting liquid refrigerant from one evaporator to the other, means for maintaining a substantially constant quantity of liquid refrigerant in said compartment, a box-like refrigerant evaporating evaporators, and a thermostat responsive to changes in temperatures in said first named evaporator and arranged to so control said means as to operate the first named evaporator at least part of the time above a frost forming temperature and the second evaporator constantly at a freezing temperature.

9. Refrigerating apparatus comprising a sheet metal shell having an opening in a wall thereof, a sheet metal member cooperating with a second wall of said shell to provide a spacefor refrigerant, a refrigerant evaporator disposed within the confines of said shell and having provisions for receiving an ice' making receptacle through said opening, means for maintaining a substantially constantle'vel of'liquid in said space for refrigerant and in said evaporator, andathermostat thermally associated with the refrigerant in said space for controlling said means. 1

10. A refrigerant evaporating element comprising a sheet metal shell including vertical wallsj and-a bottom wall, one of said vertical walls having an opening of sufilcient size to receive an ice making receptacle, sheet metal material cooperating with opposed vertical walls to provide spaces for refrigerantga.refrigerant conduit interconnectingl said spaces, and a relatively low temperature refrigerant evaporator disposed within said shell for freezing the contents of said receptacle.

11. A refrigerant evaporating element comprising a sheet metal shell including vertical walls and a bottom Wall, one of said vertical walls having an opening of suflicient size to receivelan ice making receptacle, sheet metal material cooperating with opposed vertical walls to provide spaces for refrigerant, a refrigerant conduit interconnecting said spaces, a low temperature refrigerant evaporator disposed within said shell for freezing the contents of said receptacle, and insulating material associated with said bottom wall.

12. Refrigerating apparatus comprising, in combination, a cabinet having a food storage compartment, a box-like refrigerant evaporating element constructed 'of sheet metal material and having an open top secured to an insulated wall in said compartment, said evaporating element having an open front, sheet metal means associated with opposed side walls to provide spaces for refrigerant; a refrigerant evaporating element disposed within the confines of said boxlike element and being arranged for receiving an ice making receptacle through said open front of the box-like element, and means for supplying refrigerant to said elements.

13. Refrigerating apparatus comprising,v in combination, a cabinet having a food storage compartment,`a box-like refrigerant evaporating element constructed of sheet metal materialand having an open top secured to an insulated wall provide spaces for refrigerant, and ice tray, heat.

absorbing means disposed within the confines of said element and, being arranged for supporting said. ice tray, a tray front secured tosaid tray, said tray front being arranged to close said opening when supported by said means, and means for supplying refrigerant to said element and heat absorbing means.

14. yRefrigerating apparatus comprising, in

, said second element as rapidly as the first named element, means for delivering liquid refrigerant rst to said first named element and then both liquid and gaseous refrigerant from said first element to said second element, and thermostatic means associated .with said first element for controlling the operation of said apparatus in such a mannerthat frost does not accumulate on said first element at least part of the time.

15. A refrigerating system of the flooded type comprising a refrigerant evaporating element adaptedto be positioned in a compartment for cooling circulating air, a second refrigerant evaporating element for freezing substances, a refrigerant condensing unit associated with saidA elements, a high side float mechanism for controlling the flow of refrigerant to saidflrst element, conduit means for conducting vthe flow of both liquid and gaseous refrigerant to the second element after the refrigerant haspassed through said first element, and means directly responsive to the conditionA of said first element for controlling the operation of said condensing unit.

16. Arefrigerating system of the flooded type comprising a refrigerant evaporating element adapted to be positioned in a compartment for cooling circulating air, a second refrigerant evaporating element for freezing substances, a refrigerant condensing unit associated with said elements, mechanism for controlling the flow of refrigerant to said first element, conduit means for conducting the flow of both liquid and gaseous refrigerant to the second element after the refrigerant has passed through said first element, and means directly responsive to the condition of said first element for controlling theoperation of said condensingunit.

17. A refrigerant evaporatingA element of the type adapted to be positioned in a compartment for cooling circulating air therein, comprising refrigerant containing walls exposed to the circulating air in the compartment and a bottom wall insulated so that cooling of the circulating air is accomplished only by said other walls.

LAWRENCE A. PHILIP?.

Images