US3050961A

US3050961A - Single evaporator two-compartment refrigerator

Info

Publication number: US3050961A
Application number: US116224A
Authority: US
Inventors: Leonard J Mann; John J O'connell
Original assignee: Motors Liquidation Co
Current assignee: Motors Liquidation Co
Priority date: 1961-05-09
Filing date: 1961-05-09
Publication date: 1962-08-28
Anticipated expiration: 1979-08-28

Description

Aug. 28, 1962 1.. J. MANN ETAL 6 Sheets-Sheet 1 i w w Wa INVENTORS LEONARD J. MANN JOHN J. ocomusu 1' man ATTORNEY Aug. 28, 1962 L. J. MANN ETAL 3,050,961

SINGLE EVAPORATOR TWO-COMPARTMENT REFRIGERATOR Original Filed July 8, 1960 6 Sheets-Sheet 2 INVENTOR5 LEONARD J. MANN JOHN J. O'CONNELL BY Z5555 THEIR ATTORNEY Aug. 28, 1962 J. MANN ETAL SINGLE EVAFORATOR TWO-COMPARTMENT REFRIGERATOR Original Filed July 8, 1960 6 Sheets-Sheet 3 l1lllllllllllll|llllllll|lllll llll'lulllllllll lllllullllllfillllll N \R Q INVENTORS LEONARD J. MANN JOHN J.- c u. L

THEIR ATTORNEY Aug. 28, 1962 J. MANN ETAL. 3,050,961

SINGLE EVAPORATOR TWQ-COMPARTMENT REFRIGERATOR Original Filed July 8, 1960 e Sheets- Sheet 4 THEIR ATTORNEY s 5 a I I N j 1 I I 3:

g Q k :5:

y INVENTORfi -5 LEONARD J. MANN 1 k JOHN J. o'cnmm I Q BY wp Aug. 28, 1962 J. MANN ETAL 3,050,961

SINGLE EVAPORATOR TWO-COMPARTMENT REFRIGERATOR Original Filed July 8, 1960 6 Sheets-Sheet 6 @Y Ma 5 ww INVEN-TOR5 LEONARD J. MANN JOHN J. O'CONNELL BY 7 THEIR ATTORNEY United States Patent Ofiice 3,050,961 Patented Aug. 28, 1952 3,tl50,96l SINGLE EVAPGRA'IGR TWO-QGMPARTMENT REFRIGERATGR This application is a continuation of our copending application Serial No. 41,614, filed July 8, 1960, now abandoned.

This invention relates to refrigerating apparatus and more particularly to household refrigerators with above and below freezing compartments in which frost will not collect.

Refrigerators that are free of frost are popular. Because of the high sale price, they are limited to those having larger incomes. This is partially caused by the fact that these frost-free refrigerators have been built with separate evaporators for each compartment. Attempts have been made to cool both compartments with a single evaporator. However, the rapid accumulation of frost from the air received from the above freezing compartment caused the evaporator air spaces to become rapidly clogged with frost so as to prevent the proper circulation of air between the compartments and the evaporator. This required very frequent defrosting. Furthermore, because of the relatively large accumulation of frost where the circulating air first contacted the evaporator, it was difficult to defrost the evaporator rapidly enough to prevent the below freezing compartment temperature from rising an undesirable amount.

It is an object of this invention to provide an arrangement in which a single evaporator cools the below and above freezing compartments by circulating the air in such a way that the air from the below and the above freezing compartments each initially contact the evaporator at different places to distribute the frost formation and to prevent obstruction to the air flow and to make possible rapid and complete defrosting.

It is another object of this invention to provide a refrigerator arrangement in which a single evaporator cools the below and above freezing compartments in which the air is circulated in such a way that the air from the above freezing compartment is passed along one side of the evaporator to remove the greater portion of the moisture from it before it joins the below freezing compartment circulating air in heat transfer with the remainder of the evaporator to prevent the obstruction of the air flow and to make possible rapid and complete defrosting.

These and other objects are illustrated in the two forms shown in the drawings in which the upper below freezing compartment is provided with a false bottom wall extending over the evaporator compartment which contains a folded plate type evaporator provided with louvers between the refrigerant passages so as to allow air flow through it. This evaporator compartment is divided by dividing members into a central passage and two side passages extending from the front to the rear. The above freezing compartment is provided with a false top wall having five apertures adjacent its front end through which air flows from the compartment into a duct immediately above the false top wall so that the air is conveyed to the two rear corners. At the rear corners, the air passes upwardly through the insulation and the drain pan to the side passages of the evaporator compartment. The air flows forwardly in these side passages in contact with the plate evaporator until it reaches the front end of the dividing members.

Air from the below freezing compartment passes around the front edge of its false bottom wall into the evaporator compartment. The air from the side passages as well as the air drawn from the front of the below freezing compartment is drawn through the center passage between the evaporator plates to the inlet of the fan at the rear. The moist air from the above freezing compartment first contacts the side edges of the evaporator and deposits the most of its moisture thereon in the form of frost. The air from the below freezing compartment contains much less .moisture and joins the dehumidified air from the above freezing compartment at the front where, in the rearward flow of air, much of the remainder of the moisture from the air in both compartments is deposited in the form of frost in the center passage. The blower at the rear has an upwardly extending outlet which discharges into the upper portion of the below freezing compartment and a downwardly extending outlet which discharges through a thermostatically controlled valve into the above freezing compartment. The operation of the system is normally controlled by a thermostat in the inlet to the below freezing compartment duct of the fan and controls the cycling of the refrigerating system as well as the operation of the fan. Periodically, refrigeration is discontinued and the fan is stopped while an electric heater in contact with the evaporator heats the evaporator rapidly to defrost it and to remove the frost therefrom before the compartments are permitted to warm up any substantial amount. T hereafter, refrigeration and the operation of the fan are resumed.

In a second form, the air from the above freezing compartment is passed directly into contact with the bottom of the evaporator while the air from the below freezing compartment initially contacts the evaporator at the front. This also distributes the frost during the refrigerating cycle so that clogging is reduced and defrosting the evaporator is made more rapid, uniform and complete.

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

In the drawings:

FIGURE 1 is a vertical front sectional view taken substantially along the line 11 of FIGURE 2 of a two-compartment household refrigerator embodying one form of my invention;

FIGURE 2 is a fragmentary side vertical section taken substantially along the line 2--2 of FIGURE 1;

FIGURE 3 is a horizontal sectional view taken substantially along the line 33 of FIGURE 2;

FIGURE 4 is a fragmentary vertical sectional view taken substantially along the line 4--4 of FIGURE 3 showing the louvers in section;

FIGURE 5 is a fragmentary side vertical sectional view taken substantially along the line 5-5 of FIG- URE 3;

FIGURE 6 is a plan view of the plate type evaporator shown in FIGURES 1 to 5;

FIGURE 7 is a wiring diagram for the refrigerator shown in FIGURES 1 to 6;

FIGURE 8 is a diagrammatic view of the refrigerating system shown in FIGURES 1 to 6;

FIGURE 9 is a front vertical sectional view of a modified form of the invention taken substantially along the line 99 of FIGURE 10; and

FIGURE 10 is a side vertical sectional view of the form shown in FIGURE 9 taken along the line 1010 thereof.

Referring now more particularly to FIGURES 1 to 4, there is shown a refrigerator cabinet 20 having insulated top, side and rear walls 22, 2.4 and Z6 enclosing an upper below freezing compartment 28 and a lower above freezing compartment 3t) separated by a horizontal dividing o) wall 32. The front of these

compartments

28 and 30 are closed by separate doors 34 and 35 suitably insulated. These doors seal against the metal covered insulating mullion 37 at the front of the horizontal dividing wall 32.

The above freezing compartment 38 is provided with a false top wall 34 which is spaced beneath an insulating member 36 extending rearwardly from the mullion 37 within the horizontal dividing wall 32. This insulating member 36 of foamed plastic resin has a projecting portion 38 at the front which rests upon the false 'top wall 34 and a front pointing triangular-shaped projection 48 at the rear which likewise rests upon the false wall 34. Between these projections 38 and 48 is a recessed portion 42 forming two passages which become wider as they extend forwardly from the rear corners until they join at the center. The false top wall 34 is provided with a series of five elongated apertures 44 extending across the front providing inlet openings by which air from the above freezing compartment 30 flows into the passage 42.- The false top wall 34 slopes downwardly to the'rear center providing a drain passage 46 in the central portion for the draining of any moisture which may condense on its upper face. Two passage portions 42 extend to and converge to the rear corners substantially adjacent the rear wall 26 and thence turn upwardly through the insulating member 36 and connect directly with the two rear corner openings 48 provided in a drain pan 50 resting upon the insulating member 36.

The evaporator assembly 52 rests upon the drain pan. This evaporator assembly includes a folded plate type evaporator 54 which is shown in development in FIG- URE 6. It includes a narrow entrance passage 56 extending from the center along the rear edge to the right end which connects to serpentine passages 58 formed in the plate terminating in three parallel passages 60 providing a connection with the opposite side. These three parallel passages 60 connect with the serpentine passages 62 which in turn discharge into an accumulator passage 64. A narrow slot 66 is cut out between the accumulator passage 64 and the serpentine passages 62 so that the accumulator passage may be bent upwardly at a slight angle so as to serve as a liquid trap and gas disengagement chamber. Between the serpentine passages are provided openings and louvers 68 extending in the direction of air flow for providing the free passage of air and good heat transfer between the air and the plate evaporator 54. These openings and louvers 68 are closely spaced and extend substantially between the refrigerant passages so as to provide good air flow and good heat transfer between the air and the louvers providing maximum turbulence, maximum air flow and maximum heat transfer between the air and the refrigerant in the

passages

58 and 62. Retaining tabs or clips 70 are also provided throughout the evaporator 54 for holding thereon the serpentine sheathed tubular electric heater 72 extending in serpentine fashion transverse to the

serpentine refrigerant passages

58 and 62 throughout the evaporator including a portion extending around the accumulator 64.

The plate evaporator 54 is bent crosswise substantially along the line 74 with a rounded bend as is shown in FIGURE 1 to provide two spaced evaporator portions, namely, an upper portion 76 and a lower portion 78. Between the upper and

lower portions

76 and 78 are provided two vertical dividers 88 extending from a point about one-fourth the distance back of the front edge of the plate evaporator to the rear. These dividers 80 are spaced inwardly from the sides of the plate about onesixth of the folded width of the plate as viewed in FIG- URE 1. These dividers 80 are held in spaced relation by an intervening central perforated plate 82 located between the upper and

lower portions

76 and 78 and supported by spacers 84. The dividers 80 between the

evaporator sections

76 and 78 are supplemented by the dividers or partitions 86 at the bottom and rear. These

dividers

80 and 86 confine the air flowing out of the openings 48 to the passages 88 on the outer sides of the dividers along the side edges of the evaporator 54. These passages 88 are located between the dividers and 86 and the upturned sides of the drain pan 50.

The flow of air from the above freezing compartment 34 through the side passages 88 is relatively slow. The air from the openings 48 therefore has ample contact with the adjacent surfaces of the evaporator 54 so that it is cooled and its moisture largely removed and deposited in the form of frost on the adjacent edge portions of the evaporator 54. Therefore, when the air reaches the front of the evaporator compartment, it is cooled and dried. At the front of the evaporator compartment, this air which has flowed through the side passages 88 meets the air which flows from the below freezing compartment around the front edge of the false bottom plate 90 which rests upon the heater section 72 directly beneath it. This air flows between the front edge of the false bottom wall 90 and the front edge of the drain pan 50. All this air then comingles as it flows through the central passage 92 located between the dividers 80 and rearwardly between the dividers 86 to the central rear opening 94 provided in the false bottom wall 98 as shown in FIGURE 2.

The flanged opening 94 connects directly with the trapezoidal-shaped truncated duct 96 formed of a plastic member which surrounds the scroll 98 of the fan wheel 121 driven by the electric motor 123 lodged within the recess 125 formed in the rear wall 26. The scroll 98 includes an inlet 127 providing communication with the duct 96 and interior of the fan wheel or blower 121. The scroll 98 includes an upwardly extending discharge outlet 129 and a downwardly extending discharge outlet 131. The upper discharge outlet 129 is provided with a semicircular deflecting collar 133 having a central opening 135 discharging the central portion of the air against the bottom. surface of the top wall 22 of the below freezing compartment 28. The interior passage 137 directs the air downwardly onto the sides and central portion of the false bottom wall 98. This insures even distribution of the cold air throughout the below freezing compartment 28.

The evaporator 54 is maintained at a temperature of about -15 C. under the control of a thermostat or thermostat bulb 139 located in the fan outlet opening 129 so that it is responsive to the temperature of the air after it has been cooled and dried by passage through the side passages 88 and the central passage 92 in contact with the surfaces of the evaporator 54 and the perforated bafile plate 82. This thermostat 139 is preferably set to start operation of the refrigerating system at +2 F. and a stop operation at 10 F. air temperature. The fan motor 123 and the compressor motor are connected in parallel and operatesimultaneously.

The downwardly extending outlet 131 connects directly with a discharge connection 141 at the rear of the evaporator compartment 143 and passes through an opening 145 in the insulation member 36 connecting with an elbow 147 which is connected to the inner sheet metal member 149 on the front face of the rear wall 26 in the above freezing compartment 30. This elbow is provided with a threaded connection with a valve seat 151 provided on the opposite side of the face 149 of the rear wall. This valve seat member cooperates with a valve element 153 connected by a valve stem to a metal bellows 155 supported within a plastic housing 157 having a closed rear wall and perforated side and front walls. This thermostatic bellows 155 therefore measures the temperature of the'air in the upper portion of the above freezing compartment 30 and controls the flow of cold air from the elbow 147 into the compartment 30 so as to maintain the compartment 38 between 34 and 38 F. The bellows 155 is calibrated and is charged with a suitable volatile liquid so that the valve member 153 will close against the seat member 151 at 34 F. and will move to the fully open position at 38 F. In between these temperatures, it will assume intermediate positions to maintain the above freezing compartment 30 at desired refrigerating temperatures, such as 35 F., for example. The housing 157 for the bellows 155 is fastened to the false top wall 34. A deflector 158 is located above the valve seat 151 to deflect the air for flow beneath the false top wall 34. As shown in FIGURE 7, the motorcompressor unit 159 pumps evaporated refrigerant from the accumulator as of the evaporator plate 54- and forces this compressed refrigerant into the condenser 161 which is connected by the capillary restrictor tube 163 with the restricted inlet passage as of the plate evaporator 54.

Referring now more particularly to FIGURE 7, there is shown the wiring diagram provided with a supply conductor 165 connecting through a starting relay 167 with the compresosr motor 169 of a motor-compressor unit. The starting relay 167 controls the flow of current through the phase winding 171 of the motor 169. Also connected to the supply conductor T65 is the motor 123 of the fan 121 which is connected in parallel with the motor 169 and in series with the thermostat 139. The thermostat 139 is connected to the contact 173 of a double throw switch 375 controlled by a defrost timer 177. Periodically, such as once a day, the double throw switch 175 is moved to its upper position into contact with the stationary contact 179. The switch 175 as well as the defrost timer 177 are connected to the second supply conductor 131.

When the defrost timer 177 operates to move the switch 175 away from the contact 173 into contact with the contact 179, a defrost cycle is initiated. This deenergizes the

motors

169 and 123 to stop refrigeration and air circulation. It energizes the heater 72 through a normally closed defrost limiter thermostat 183 located on the right rear portion of the drain pan as shown in FIGURES 3 and 5. The heater 72 rapidly heats the evaporator 54 and the evaporator compartment 143 so that the frost is melted and collected by the drain pan for disposal through a frost Water discharge duct 185 shown in FIGURE 3. The heating continues a sufficient length of time to melt the frost. The heating is terminated when the defrost limiter thermostat 183 reaches a sufficiently high temperature, such as 40 or 415 which indicates the condition insuring completion of the defrosting. When this temperature is reached, the limiter thermostat 183 is opened. This, then effectively energizes the electromagnet 187 in a shunt circuit around the limiter thermostat 183. This electromagnet 187 then operates the double throw switch T175 back to its normal position in contact with the contact 173 so that refrigeration can be resumed since the switch 139 will be closed by the warmer conditions prevailing during the defrost operation. In the event that the defrost limiter switch 183 fails to operate, the switch 175 will be returned to its normal position by the defrost timer l7 7 Thus, in this form, air is drawn through passages between the insulation member 36 and the false top wall 34 of the above freezing compartment keeping this false wall 34 at substantially the highest temperature in the above freezing compartment so that no moisture will collect on it. This air first contacts the edges of the evaporator so that a substantial portion of its moisture is deposited in the form of frost as it is cooled by these surfaces before this air merges with the colder, drier air coming from the below freezing compartment 28. The merged air is cool and dry and is further cooled and further dried in its rearward movement through the central passage 9?. for distribution to the two compartments by the fan and ductwork. This keeps the below freezing compartment 23 at a temperature between about and F. and sufficiently dry to prevent substantially the formation of any frost therein. The above freezing compartment 30 is kept at a temperature of about 35 by the thermostatically controlled valve 153 which controls the rate of air flow into and through the above freezing compartment 30. The plate type of evaporator provides sufiicient turbulence of the air to obtain good heat transfer between the air and its surfaces. Considerable amount of frost can collect on its surfaces without materially affecting the flow of air. The accumulation of frost on its surfaces is substantially uniform and this prevents obstructions to air flow and makes the defrosting rapid and uniform. This refrigerator is efficient and yet relatively inexpensive to manufacture and also prevents any formation of frost in the below freezing compartment 28. The defrosting system automatically removes frost without any attention of the owner.

In the form shown in FIGURES 9 and 10, similar parts to those found in FlGURES 1 to 8 are given the same reference characters and the description thereof will not be repeated. This form shown in FIGURES 9 and 10 differs primarily in that the partitions or dividers and fit: are omitted and a different air circulating system within the evaporator compartment 243 is provided. The false top wall 234 of the above freezing compartment is provided with a series of four rows of distributed inlets which extend from side to side across the false top wall They communicate with a recess 242 provided in the insulation member 236 above the false top wall 234*. The insulation member 236 is provided with four rows of vertically extending passages 245 directly over the openings 244 in the false bottom wall 234 and extending upwardly from the recess 242 to a recess adjacent the apertures Z45. Directly above these holes or passages 245 are located the large apertures 248 in the drain pan 259;. The drain pan 25%) is generally similar to the drain pan 5% with the exception of the difference in location of holes. Within the evaporator compartment 2 13 is the folded plate type evaporator 254 which is similar to the evaporator shown in development in FIG- URE 6. However, the plate 82 is omitted but the evaporator is provided with serpentine sheathed tubular electric heaters 272 above and below in a manner similar to the first embodiment. The lower section of heaters rest directly on the drain pan 250 while the false bottom wall 50 rests directly on the upper series of the sheathed electric heater 272.

In this form, operation of the blower or fan 121 causes air to be drawn from the below freezing compartment 28 around the front end of the false bottom wall into the evaporator space 243 where it contacts the front edge of the evaporator 254 initially. Air is also drawn from the above freezin compartment 3t through the holes 244 in the false top wall 234, through the passages 245 in the insulation member 236 and through the apertures in the drain pan 25d to initially contact the bottom surface of the lower section of the plate evaporator 254 at a point directly above the opening 248. The initial contact therefore is considerably different and spaced rearwardly from the initial contact of the air from the below freezing compartment 23. Since the plate evaporator 254- is louvered as shown in FIGURES 3 and 6, the air flows freely in contact with the evaporator 254 and is drawn rearwardly, transferring heat and moisture to the plate evaporator 254 in its passage to the opening 1% in the false bottom wall 9t). The cold air flows upwardly into the fan or blower 121 in a manner similar to the first embodiment. The controls of air flow and temperature are similar.

In this form, the warmer moist air from the above freezing compartment 36 first contacts the bottom of the evaporator 254 at a point behind the front edge of the evaporator and generally in the front half of the evaporator 254. This air moves rearwardly and distributes its moisture to the rear part of the evaporator 254 so as to provide a relatively uniform distribution of frost upon the surfaces of the evaporator. The colder, drier air from the below freezing compartment 28 first contacts the front edge of the upper section of the evaporator 254 and then the lower front edge and distributes its moisture 'in the form of frost to a greater extent upon the upper section of the evaporator 254. This type of air movement also serves to distribute the frost more uniformly on the surfaces of the evaporator 254 so that clogging of the air passages by frost is diminished and defrosting can take place rapidly and uniformly. A similar system of control shown in FIGURES 7 and 8 may be used for this form of the invention. Thus, in both forms of the invention, the air from the two difierent compartments contact initially the evaporator in different areas so that the frost is relatively uniformly distributed and the clogging of the air passages is minimized.

While the embodiments of the present invention as herein disclosed constitute preferred forms, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. A refrigerator including insulating means enclosing a below freezing compartment and an above freezing compartment, means forming an evaporator compartment separated from said compartments containing an evaporator portion, means for circulating air from said below and above freezing compartments through said evaporator compartment in heat transfer with said evaporator portion and in commingling relationship and returning the cooled air to said above and below freezing compartments, said circulating means including means for proportioning the circulation of the air to maintain said below and above freezing compartments at temperatures below and above freezing respectively, and cooling means for precooling said air circulating from said above freezing compartment prior to its commingling with said below freezing compartment air.

2. A refrigerator including insulating means enclosing at below freezing compartment and an above freezing compartment, means forming an evaporator compartment separated from said compartments containing an evaporator portion, means for circulating air from said below and above freezing compartments through said evaporator compartment in heat transfer contact with said evaporator portion and in commingling relationship and returning the cooled air to said above and below freezing compartments, said circulating means including means for proportioning the circulation of the air to maintain said below and above freezing compartments at temperatures below and abovefreezing respectively, and means for removing moisture from said air circulating from said above freezing compartment while separated from said below freezing compartment air prior to its contact with said evaporator portion.

3. A refrigerator including insulating means enclosing a below freezing compartment and an above freezing compartment, means forming an evaporator compartment separated from said compartments containing an evaporator portion and having an outlet, fan means having an inlet connected to said outlet and having discharge outlet means discharging into said below and above freezing compartments, separate inlet passage means extending from said below and above freezing compartments to said evaporator portion for conducting air from the below and above freezing compartments to said evaporator portion, said fan means drawing air from said compartments through said passage means and evaporator compartment in heat transfer with said evaporator portion, and means for removing moisture from said air passing through said separate inlet passage means from said above freezing compartment prior to joining said below freezing compartment air. 7

4. A refrigerator including insulating means enclosing a below freezing compartment and an above freezing compartment, means forming an evaporator compartment separated from said compartments containing an evaporator portion and having an outlet, fan means having an inlet connected to said outlet and having discharge outlet means discharging into said below and above freezing compartments, separate inlet passage means extending from said below and above freezing compartments to said evaporator portion for conducting air from the below and above freezing compartments to said evaporator portion, said fan means drawing air from said compartments through said passage means and evaporator compartment in heat transfer with said evaporator portion, and cooling means maintained at temperatures substantially as low as the temperature of the air from said below freezing compartment extending into heat transfer with said air passing through said separate inlet passage means from said above freezing compartment for precooiing the air from said above freezing compartment prior to joining said below freezing compartment air.

5. A refrigerator including insulating means enclosing a below freezing compartment and an above freezing compartment, means forming an evaporator compartment separated from said compartments containing an evaporator portion and having an outlet, fan means having an inlet connected to said outlet and having discharge outlet means discharging into said below and above freezing compartments, separate inlet passage means extenning from said below and above freezing compartments to said evaporator portion for conducting air from the below and above freezing compartments to said evaporator portion, said fan means drawing air from said compartments through said passage means and evaporator compartment in heat transfer with said evaporator portion, and cooling means normally maintained at temperatures substanti "ly as low as the temperature of said l evaporator portion extending into heat transfer with and cooling and removing moisture from said air passing through said inlet passage means from said above freezing compartment by the deposit of frost prior to joining said below freezing compartment air, and means for defrosting said cooling means.

6. A refrigerator including insulating means enclosing 9. below freezin compartment and an above freezing compartment and door means for access to said compartments, means associated with said insulating means forming evaporator compartment means separated from said below and above freezing compartments, means for circulating air from said below and above freezing compartments through said evaporator compartment means and returning the air to said above and below freezing compartments, said evaporator compartment means having separating means arranged to provide a second zone for air from the above freezing compartment and a first zone connected with the second to mix the air from said below and above freezing compartments, an evaporating means including a first evaporator portion located in said first zone of said evaporator compartment in heat transfer with said mixed air from said below and above freezing compartments and a second evaporator portion located in said second zone in heat transfer with the air circulating from said above freezing compartment prior to its mixing with said below freezing compartment air.

7. A refrigerator including insulating means enclosing a below freezing compartment and an above freezing compartment and door means for access to said compartments, means associated with said insulating means formmg evaporator compartment means separated from said below and above freezing compartments, said evaporator compartment means including a first part containmg a first evaporator portion and a second part containmg a second evaporator portion, means for circulating air separately from said above freezing compartment separately to said first part in heat transfer with said first evaporator portion and then circulating this precooled air together with air from the below freezing compartment through said second part in heat transfer with said second evaporator portion and returning the combined air to said compartments, said circulating means includmg means for proportioning the circulation of the air to maintain said above and below freezing compartments respectively at above and below freezing temperatures.

8. A refrigerator including insulating means enclosing a below freezing compartment and an above freezing compartment and door means for access to said compartments, means associated with said insulating means forming evaporator compartment means separated from said below and above freezing compartments, said evap orator compartment means including a first part containing a first evaporator portion and a second part containing a second evaporator portion, means for circulating air separately from said above freezing compartment separately to said first part in heat transfer with said first evaporator portion and then circulating this precooled air together with air from the below freezing compartment through said second part in heat transfer with said second evaporator portion and returning the combined air to said compartments, said circulating means including means for proportioning the circulation of the air to maintain said above and below freezing compartments respectively at above and below freezing temperatures, and means for simultaneously defrosting said first and second evaporator portions.

9. A refrigerator including insulating means enclosing a below freezing compartment and an above freezing compartment, means associated with said insulating means forming an extensive evaporator compartment, an evaporator extending within said evaporator compartment, said evaporator compartment having an outlet adjacent one edge of the evaporator, fan means having an inlet connected to said outlet and having two outlets with one of the outlets discharging into the below freezing compartment and the second outlet extending to the above freezing compartment, said means forming the evaporator compartment being provided with first passage means located to conduct air from said above freezing compartment first into contact with one portion of the evaporator and provided with a second passage means located in another portion to conduct air from said below freezing compartment into contact with another portion of said evaporator and connecting with the first passage means.

10. A refrigerator including insulating means enclosing a below freezing compartment and an above freezing compartment, means associated with said insulating means forming an extensive thin evaporator compartment, an evaporator extending within said evaporator compartment, said evaporator compartment having an outlet adjacent one edge of the evaporator, fan means having an inlet connected to said outlet and having outlet means, discharge means extending from said outlet means to said below freezing compartment, and conduit means extending from said outlet means to said above freezing compartment, said means forming the evaporator compartment being provided with first passage means located beyond the edge opposite said one edge of said evaporator providing communication between said below freezing compartment and said evaporator compartment for delivering said below freezing compartment air to said edge opposite of said evaporator, said means forming the evaporator compartment being also provided with separate second passage means located adjacent to and in heat transfer with the evaporator between said one and said opposite edges and extending therefrom to said edge opposite, said insulating means being provided with third passage means extending from said above freezing com partment to said second passage means providing in combination with the second passage means for the flow of above freezing compartment air from said above freezing compartment through said second passage means into heat tnansfer with the evaporator between said one and said opposite edges prior to mixing with said below freezing compartment air in said first passage means.

11. A refrigerator including insulating means enclosing a below freezing compartment and an above freezing compartment below said below freezing compartment, means associated with said insulating means forming an evaporator compartment between said below and above freezing compartments, an evaporator extending within said evaporator compartment, said evaporator compartment having an outlet, fan means having an inlet connected to said outlet and having outlet means discharging into the below freezing compartment and the above freezing compartment, said means forming the evaporator compartment being provided with a portion of said insulating means and a thin wall separating the evaporator and the evaporator compartment from said above freezing compartment with passage means extending between said portion and said thin wall and connecting with and providing communication between said above freezing compartment and said evaporator compartment for conducting air from said above freezing compartment to said evaporator compartment.

12. A refrigerator including insulating means enclosing a below freezing compartment and an above freezing compartment and door means for access to said on partments, means associated with said insulating means forming an evaporator compartment, an evaporator extending within said evaporator compartment, means dividing said evaporator compartment into a first common passage having an inlet for mixed air from the below and above freezing compartments extending into contact with and embracing a first section constituting the greater portion of the evaporator and also having an outlet and a second passage solely for above freezing compartment air extending into contact with a second section of the evaporator and embracing one edge of the evaporator and connecting at one end with the above freezing compartment and connecting at the opposite end with said inlet of said first passage, said inlet of said first passage also communicating with the below freezing compartment for receiving therefrom, and fan means having its inlet connected to said outlet of said first passage and having outlet means connected to said above and below freezing compartments.

13. A refnigerator including insulating means enclosing a below freezing compartment and an above freezing compartment and door means for access to said compartments, means associated with said insulating means forming an extensive generally rectangular evaporator compartment, a generally rectangular evaporator extending within said evaporator compartment, means dividing said evaporator compartment into a central common passage embracing the central portion of the evaporator and having an inlet and an outlet adjacent opposite edges of the evaporator and side passages embracing the other edges of said evaporator and each connected at one end to the inlet of said central portion and extending at the other end to one of two corners of said evaporator compartment, said insulating means including passages extending from said above freezing compartment to said two corners of said evaporator compartment, and means for drawing air from said outlet of said central passage and discharging the air into said below and above freezing compartments.

14. A refrigerator including insulating means enclosing an upper below freezing compartment and a lower above freezing compartment, a wall separating said compart ments including a lower layer of insulation and a laterally extending evaporator compartment above the insulation and a thin laterally extending divider separating the evaporator compartment and the below freezing compartment, a laterally extending evaporator within said evaporator compartment, said divider being provided with an inlet opening and an outlet opening on opposite sides of said evaporator and communicating with said evaporator compartment, said layer of insulation being provided with passage means extending from said above freezing compartment to said evaporator compartment immediately adjacent to an intermediate portion of said evaporator, fan means having an inlet connected to said outlet and having outlet means, discharge means extending from said 1 1 outlet means to said below freezing compartment, and conduit means extending from said outlet means to said above freezing compartment.

15. A refrigerator including insulating means enclosing an upper below freezing compartment and a lower above freezing compartment, a wall separating said compartments including a lower layer of insulation and a laterally extending evaporator compartment above the insulation and a thin laterally extending divider separating the evaporator compartment and the below freezing compartment, a. laterally extending evaporator within said evaporator compartment, said evaporator compartment being provided with an inlet adjacent the front of the below freezing compartment and an outlet adjacent the rear of the below freezing compartment, said layer of insulation being provided with passage means extending from said above freezing compartment to said evaporator compartment immediately adjacent to an intermediate portion of said evaporator, fan means having an inlet connected to said outlet and having two outlets with one of the outlets discharging into the below freezing compartment and the second outlet discharging into the above freezing compartment.

16. A refrigerator including insulating means enclosing at below freezing compartment and an above freezing compartment, means associated with said insulating means forming an extensive thin evaporator compartment, an evaporator extending within said evaporator compartment, said evaporator compartment having an outlet adjacent one edge of the evaporator, fan means havingan inlet connected to said outlet and having two outlets with one of the outlets discharging into the below freezing corm partment and the second outlet extending tothe above freezing compartment, said means forming the evaporator compartment being provided with first passage means at the front extending from the front of the below freezing compartment to the front of the evaporator compartment in front of the evaporator, said means forming the evaporator compartment being provided with bottom passage means extending from the top of the above freezing compartment to the bottom of said evaporator compartment rearwardly of the front of the evaporator, said means forming the evaporator compartment also including a third passage means extending from said first passage means rearwardly in contact with said evaporator to said outlet.

17. A refrigerator including insulating means enclosing an upper below freezing compartment and a lower above freezing compartment, a wall separating said compartments including a lower layer of insulation and a laterally extending evaporator compartment above the insulation and a thin laterally extending divider separating the evaporator compartment and the below freezing compartment, 8. laterally extending evaporator within said evaporator compartment, said divider being provided with an opening at the front in front of the evaporator providing for the flow of air from the below freezing compartment to the front of the evaporator compartment, said layer of insulation being provided with passage means rearwardly of the front of the evaporator extending from the above freezing compartment to a portion of said evaporator compartment rearwardly of the front of the evaporator so as to contact first a different portion of the evaporator than is contacted first by the air from the below freezing compartment, fan means having an inlet connected to the rear of said evaporator compartment behind said evaporator and having two outlets with one of the outlets discharging into the below freezing compartment and the second outlet discharging into the above freezing compartment.

18. A refrigerator including insulating means enclosing a below freezing compartment and an above freezing compartment, means associated with said insulating means forming an extensive thin evaporator compartment, an evaporator extending within said evaporator compartment, said evaporator compartment having an outlet adjacent one edge of the evaporator, fan means having an inlet connected to said outlet and having two outlets with one of the outlets discharging into the below freezing compartment and the second outlet extending to the above freezing compartment, means dividing said evaporator compartment into a common passage for both below and above freezing compartment air extending into heat transfer with a major portion of said evaporator to the inlet of the fan means and a second separate passage solely for above freezing compartment air extending into heat trans fer with another portion of said evaporator to said common passage for cooling and drying the above freezing compartment air prior to its joining with said below freezing compartment air in said common passage, said means forming said evaporator compartment being provided with passage means extending from said below freezing compartment to said common passage prior to the heat transfer with said evaporator.

References Cited in the file of this patent UNITED STATES PATENTS 2,180,974 Atchison Nov. 21, 1939 2,730,867 Salisbury Jan. 17, 1956 2,907,180 Mann Oct. 6, I959