Refrigerator

Dec. 6, 1938. d. c. clarke 2,139,441

REFRIGERATOR Filed July 1, 1933 -4 Sheets-Sheet 1

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BY

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INVENTOR

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ATTORNEY

Dec. 6, 1938.

D. C. CLARKE

2,139,441

REFRIGERATOR .Filed July 1, 1933

Sheets-Sheet 2

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Dec. 6, 1938. D. C. CLARKE 2,139,441

REFRIGERATOR Filed July 1, 1933 4 Sheets-Sheet 3

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Dec. 6. 1938.

D. C. CLARKE

REFRIGERATOR

2,139,441

Filed July 1, 1933 4 Sheets-Sheet 4

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ATTORNEY^

Patented Dec. 6, 1938

2,139,441

UNITED STATES PATENT OFFICE

2,139,441 REFRIGERATOR Douglas C. Clarke, Mountain Lakes, N. 3., assignor to Edgar Alfred Self, New Fork, N. Y. Application July 1, 1933, Serial No. 678,603

Claims.

This invention relates to refrigerators and more especially to refrigerators for domestic use.

An object of the invention is to provide a refrigerator which will conserve the cold air to 5 an unusually large extent.

A further object is the provision of a refrigerator from which articles may be removed with a particularly high degree of ease and efficiency.

A still further object is the provision of a re10 frigerator which is particularly well adapted for household use.

An additional object is the provision of a refrigerator which can be economically manufactured and assembled, which has an attractive ap15 pearance, in which the available space is efficiently utilized, and which will effectively carry out the purposes for which it is intended.

Still another object is the provision of a refrigerator adapted for the efficient transfer of heat 20 from the air chamber to the cooling unit in an indirect manner.

Another object is the provision of automatic refrigerators wherein freedom from frosting and dehydration problems may be obtained.

&lt;2.5 Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises an article of manufacture possessing the features, properties, and the relation of elements which will be CO exemplified in the article hereinafter described and the scope of the application of which will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention reference should be had 35 to the following detailed description taken in connection with the accompanying drawings, in which:

Figure 1 is a perspective view of one form of refrigerator embodying the invention, showing 40 one of the box-like trays with its associated supplemental tray both in outward position;

Fig. 2 ’ ·. a similar view showing the supplemental tray in inward position;

Fig. 3 is a similar view showing the other boxlike tray in outward position;

Fig. 4 is a detail perspective view of the supplemental tray shown in Fig. 1 and its mounting means;

Fig. 5 is a rear perspective view with the oper50 ating mechanism dotted in;

Fig. 6 is a vertical sectional view along the line 6—6 of Fig. 5;

Fig. 7 is a horizontal sectional view along the line 7—7 in Fig. 6, with certain parts broken away 55 to reveal the details of the valve means;

(CL 62—89)

Fig. 8 is a horizontal sectional view along the lines 8—8 of Hg. 6;

Hg. 9 is a similar view along the lines 9—9 of Hg. 6;

Fig. 10 is a perspective view of another form S of refrigerator embodying the invention, showing one tray in an outward position and another tray partly projecting;

Hg. 11 is a vertical section along the line II—II in Fig. 10; 10

Fig. 12 is a horizontal sectional view along the line 12—12 of Fig. 11;

Hg. 13 is a rear perspective view with the operating mechanism dotted in; ·

Hg. 14 is a detail end view of the ice-cube 15 trays in the ice-cube compartment;

Hg. 15 is a longitudinal sectional view along the line 15—15 of Hg. 14;

Hg. 16 is a sectional detailed view from a point just to the left of the pivot rod at Fig. 10 show- 20 ing in detail a special form of mounting for the trays of Fig. 10;

Hg. 17 is a view similar to Hg. 16 showing the parts when the tray is in an outward position;

Figs. 18 and 19 are horizontal and vertical sec- 25 tlonal views respectively of a modified form of the refrigerator shown in Figs. 10 through 15, Fig. 19 being a transverse section along the line 19—19 of Hg. 18;

Hg. 20 is a perspective view of still another 30 form of construction embodying the invention;

Fig. 21 is a transverse section along the line 21—21 of Hg. 20; and

Hg. 22 is a perspective view of the cooling and heat-transfer portions of the construction shown 35 in Hg. 20.

In ordinary refrigerators, particularly refrigerators designed for household use, the opening of a door permits the cold air contained in the refrigerator to pour out and hot air to move in. 40 So marked is the rush of cold air from the refrigerator that a ribbon positioned near the bottom of the door will be blown outwardly by the flow. Since a household refrigerator is opened several times during the preparation of 45 even a single meal, it will be seen that a large quantity of ice or power is required to constantly cool off the hot air which replaces the previously chilled air.

Another objection to the ordinary type of re- 60 frigerators lies in the fact that in the usual household refrigerator the contents remain wholly within the casing, and in order to be removed must be individually lifted and withdrawn, so that in order to lift out an article in the back 55

2,189,441 of the refrigerator, several articles in the front of the refrigerator must first be removed.

With the foregoing and other difficulties in view, the present invention contemplates the 5 provision of a refrigerator having individual boxlike, air-retaining trays which can be moved, preferably on a pivot, from the casing to permit ready access to all the contents thereof, and the provision of constructions of such nature that 10 each box-like tray, either alone or together with a compartment which contains it, provides a basin for the retention of the cold air which was contained in the tray when it was within the refrigerator. The invention further contem16 plates the provision of a refrigerator wherein no flow of cold air from an upper tray to a lower tray can occur when the lower tray has been moved outwardly. Such outward flow of cold air would naturally result in a compensat20 ing flow of hot air into the upper tray and/or its compartment, and would further result in the wastage of a large quantity of cold air which would be pushed out of the lower tray as it was closed. In accordance with the invention, the 26 flow of cold and warm air between several trays and/or compartments when a tray is moved outwardly may be prevented either by the provision of continuously acting flow-preventing means or by the provision of means for closing an upper 30 opening Trtien a lower door or tray is moved outwardly.

The Invention also contemplates the provision of various features of construction whereby the operation, appearance or contour of a refriger36 ator may be enhanced. Among such features are the provision of trays which are adapted to be swung substantially 180° so as to project a minimum amount with respect to their capacity; the provision of trays which may be 40 swung outwardly in either direction; the provision of supplemental trays whereby the holding capacity of one of the box-like trays may be increased; the location of various parts of the mechanism in the rear corner portions of the 45 refrigerator; the provision of improved holding means for ice cube trays, etc.

The tendency toward condensation and frosting with accompanying dehydration of the contents of the refrigerator and necessity for de60 frosting is likewise a serious drawback to present day automatic refrigerators; and with these and other problems in view, the invention further contemplates the provision in a refrigerator arranged for the indirect cooling of an air cham55 ber, of a liquid which will transfer heat in an especially effective and efficient manner; and the provision of a refrigerator with indirect cooling means so arranged as to maint°.in continued freezing temperatures in one compartment and 80 normal refrigeration temperatures in another compartment.

In the drawings there are illustrated two of the many forms of refrigerators which may be constructed in accordance with the invention. 66 The exemplified forms are particularly adapted for household use, and are of the electricallyoperated type. It will be understood, however, that the invention is adapted for use with a wide variety of types of refrigerators.

The form of refrigerator exemplified in Figs. 1 through 9 includes a casing 20 which is generally rectangular in shape, and an enclosing body of insulating walls 21 including doors 22, 23 and 24. The door 22 opens into an ice cube com76 partment 25, the door 23 into a food compart ment 26 and the door 24 into a food and bottle compartment 27. A plate 28 separates the compartments 25 and 26, and a plate 29 separates the compartments 26 and 27. The doors 23 and 24 form respectively a part of the box-like trays 6 30 and 31, each having a bottom wall 33 and an arcuate wall 34. The trays are mounted on a centrally disposed vertical rod 35, so that as a door is opened the tray of which it forms a part is swung outwardly. The trays in the pres- 10 ent instance are semi-circular and the doors are adapted to swing through an arc of substantially 180°. Sealing means 36 and 37, which may be composed of rubber, are provided on the casing tightly to seal the space between the casing and 16 the walls 33 and 34 of the trays when they are in an outward position. It will accordingly be seen that as either of the trays is swung outwardly the cold air in the tray-containing compartments cannot escape, but tends to settle into a basin 20 provided by the bottom of the tray and the bottom of the compartment. The top of the tray and the compartment receives warm air from the outside, but the difference in temperature of the two layers of air will ordinarily be sufficient to 25 prevent any considerable mixing until the door is again closed, when the closing action will result in pushing out of the tray a large part of the warm air which is contained in the upper part of the tray and compartment and in push- 30 ing out only a small part of the cold air which was originally contained in the compartment. Accordingly, there is a very marked saving in cold air and a relatively slight need for re-cooling after the opening of a door or the removal or de- 35 posit of an article from or in the refrigerator.

If the compartments are permanently sealed one from another, there will, as will be evident, be very little loss in he cold air from the refrigerator. However, it is often preferable from an &lt;q economical standpoint to cool the entire refrigerator directly by the flow of air from a single cooling unit, and to this end the plates 28 (Fig. 7) and 29 (Fig. 8) are provided, in the present instance, with openings 38 (Fig. 7); the plate 29 45 being disposed sufficiently below the bottom wall of the tray 30 so that cold air may flow under the tray to the openings. In order, however, to prevent the warm air which flows into the top of a compartment when the tray is opened from re- jq placing the cold air in the compartment above it, means are provided to close the opening above a tray at the beginning of the outward swinging movement of the tray. The particular mechanism exemplified in Fig. 7 comprises valve plates ¢5 39 riding In tracks 40. Each plate is pressed outwardly by a spring 41 and is formed with openings 42 adapted to register with the openings 38 when the door is closed. The outjvard movement of the plates 39 is limited by stops 43 at the ends 00 of the tracks so that when the tray is opened the openings 42 will be in non-registering position as indicated in Fig. 7. By this means all flow of air between an upper and a lower compartment is prevented when a tray in the lower compart- 05 ment is In outward position, whereas a free flow of air through the refrigerator is permitted when the doors are closed. It will be apparent that there is no need of sealing the space between the compartments 26 and 27 when the tray 30 is 70 in outward position, since the cold air in the compartment 27 will not rise and the bottom of the tray 31 and the compartment 26 will still serve as a basin for the retention of the cold air which was originally therein. 76

3,139,441

The compartment 25 contains an expansion unit 44, portions of which surround supporting means 45 for ice trays 46. These ice-cube trays are preferably mounted by means such as illus5 trated in detail in Figs. 14 and 15. In a chamber 41 at one side of the compartment and outside of the insulation 21, there is disposed in the present instance a motor 41α and a compressor 48. In ordinary refrigerators, this space is made large 10 enough to contain also a condenser unit or else the condenser unit is disposed outside of the casing. In the present instance, however, space is conserved by disposing condenser coils in the corner space 49 as indicated at 50 (see Fig. 5). If 15 desired, and as hereinafter exemplified, other portions of the operating mechanism may be disposed in such space. By the provision of openings at the top and at the bottom of the chambers 49, a very efficient cooling of the condenser coils 20 may be obtained due to the induced draft through the vertical chambers over the,coils. Vent openings may be formed in the bottom, top or side walls of the casing as desired. In the present instance, openings 50α are provided in the side of 25 the casing for admitting the air into the bottom of the chambers 49, and openings 50b are provided in the side of the casing for the escape of air from the top of these chambers. These corner chambers provide a large amount of space 30 for the condenser means, which permits a, particularly efficient cooling, and tends to reduce the frequency of the periods wherein the motor must be operated.

In order to reduce the number of compartments 35 in the refrigerator, it is desirable that each tray have considerable depth. Since, however, the ordinary contents of a refrigerator are not particularly high, the invention includes as one of its features the provision of supplemental trays 40 which, in the exemplified construction, provide an extra floor above the floor of each box-like tray. A supplemental tray 51 is provided in the box-like tray 30, and a supplemental tray 52 is provided in the box-like tray 31. The tray 51 is semi45 circular in shape and comprises a floor 53 and bracing members 54, which are, in the present instance, suitably perforated to make handles for the removal of same. The tray is mounted upon an arm 55, carrying a sleeve 56, which extends 50 about the pivot rod 35 so that the tray may be swung inwardly and outwardly with ease. In order to permit the tray 51 to be removed so as to clean the compartment 26, or so as to permit the high articles to be placed in the tray 30, the tray 55 51 is removably mounted on the arm 55 by means of a socket portion 51 adapted to fT. over a wedgeshaped member 58 on the arm 55. It may be noted in this connection that the bracing members 54 serve to completely surround the floor of 60 the tray 5i so that any liquid spilled on this floor will not flow back into the compartment but may be readily cleaned from the floor 53 of the tray. Similarly, the trays 30 and 31 are provided with guard rails 59 which, together with lhe walls 34, 65 and the doors, serve to prevent materials spilled in these trays from running off on the floor thereof. As will be seen, the tray 51 swings independently of the tray 30, so that i, may be left within the compartment, as indicated in Fig. 2, to permit 70 the articles on the floor of the tray 30 to be removed, or may be swung ou wardly, as shown in Fig. 1, to permit articles on the floor of the tray 51 to be removed. The tray 52 is similar to the tray 51, except that it is only half the size thereof. 75 This permits half of the tray 31 to be used as a bottle retainer, as indicated in Fig. 3. The tray 52 is normally held in the far end of the tray 31 by means of a catch mechanism 60, including a latch 61. When the tray 3 i is moved outwardly the tray 52 moves outwardly with it, but may be 5 pushed back into the compartment 21 upon the release of the latch. The box-like tray 31 is provided with a small arm 63, which limits the outward movement of the tray 52 and pushes the tray 52 into the far end of the compartment 21 10 when the door 24 is closed. The tray 52 is provided with strengthening members 64 similar to the strengthening members 54, and is removably mounted on an arm similar to the arm 55.

If desired there may also be provided doors 65, 15 66 and 61 opening respectively to the chamber 41, to the far side of the compartment 26, and to· the far side of the compartment 21, so as to permit ready access to the chambers in question, for the purpose of repair, cleaning, etc. 20

The form of refrigerator exemplified in Figs. 10 through 15 includes a casing 70, which is generally rectangular in shape, and an enclosing body of insulation II and an insulating door 12. Within the enclosing body 11 is a chamber 13 for a suit- 25 able cooling fluid which niay be air, brine or other suitable fluid, but which is preferably a liquid of the type hereinafter exemplified. The inner wall 14 of the chamber 13 is formed of highly conductive material, such as sheet metal, and is .30 semi-cylindrical in shape to provide a space for the accommodation of a plurality of semi-circular trays 15. In the present instance, these trays are closely juxtaposed and are each formed with an imperforate bottom wall 16, an upstand- 35 ing imperforate seml-cyllndrical wall 11, and an upstanding imperforate diametrical wall 18. Each tray thus forms a unit for retaining cold air. Egress of air from this unit can occur only over the top thereof, so that there is a minimum tend- 40 ency for cold air therein to be displaced by hot air above the same.

Each tray 15 is mounted on a centrally-disposed vertical pivot rod 19 by means of a sleeve 80. This sleeve is mounted on the upstanding wall 18 45 of the tray. The wall 18 is desirably provided with re-enforcing means 81, preferably carrying ¹ bracing tabs 82 which are secured to the semicylindrical wall 11. Suitable ball-bearing means may be provided between the individual trays and ₅₀roller bearings between the sleeves and the pivot rod, if desired.. As will be seen, each tray 15 can be swung in either direction about its pivot so that pressure on either end thereof will initiate an outward swinging movement, which can be 55 completed by drawing out the other end. Desirably, rubber friction members 83 are provided on the inside of the wall 14 so as to assist in setting the trays evenly within the refrigerator to permit the closing of the door 12, and so as to 60 resist movement of the tray beyond a 180° position, so that the outward swinging movement will not automatically carry the tray back into the refrigerator. Rubber cushion members 83α are provided on the front walls of the trays. As will be 65 seen, each tray provides, in itself, a basin for the retention of cold air. As the tray is pushed outwardly in either direction, warm air from the outside follows it in. This air, however, is pushed out when the tray is again closed, so that the only 70 loss is through such slight chilling of this air as may occur during the short time when the tray is in an outward position. The air which is in the tray loses some of its chill, as by radiation, etc., while the tray is pulled out. In order to 75

9,189,441 permit the contents of the trays to be readily viewed When door 72 is opened each tray 75 is provided with a transparent window 81b.

In the present exemplification there is provided 5 an ice cube compartment 84 and a bottle compartment 85, which are provided with individual doors 86 and 87, respectively. These compartments may be of any desired depth depending on the amount of space required for the operating 10 mechanism. In the present Instance they are of such depth as to permit' corner portions 88 and 88, which are provided between the casing 70 and the Insulation 71, to be extended upwardly to the top of the refrigerator. In. the present in15 stance, the entire operating mechanism is included in these corner spaces, an expansion chamber 00 being, provided about the compartment 84 and a chamber 91, which communicates with the chamber 73. This mechanism comprises a motor 2o 92 and a compressor pump 93, as well as condenser colls 84 and 95. Openings in the casing at these corner portions are provided as shown at 96 and 97 to permit a draft of air to flow over the mechanism. . As above indicated, such a construction 25 provides for efficient and economical operation, as well as for the economical utilization of space.

It is to be observed that since the chamber 73 is sealed, no condensation problems arise in connection therewith, and since the temperature of 30 the fluid in chamber 73 1s higher than the temperature of the fluid in the expansion chamber, and since a very small amount of hot moist air enters the refrigerator when it is opened, the tendency for condensation to form in the tray ₃₅ compartment is minimized. Such condensation as occurs may be caught in a sump 98, from which . it may be removed when necessary_; Ordinarily the temperature of the fluid in the chamber 73 will be kept higher than the freezing point of water, and in such case none of the frosting which has proved so troublesome in the ordinary refrigerator can occur. Furthermore, the marked tendency for dehydration which is a serious drawback in ordinary electric refrigerators is not present.

The ice cube trays 99 are mounted on edge supports 100, carried on members 101, forming a forwardly-inclined gutter 102. Any liquid spilling from the trays runs down the gutter and is collected in the sump IOS, from which it may be Z readily removed by a cloth.

An additional feature of the invention resides in the provision, in a refrigerator having an air chamber and an elevated cooling unit, of improved means for cooling the air chamber. Such - means as contemplated by the invention is an ⁰ enclosure which embodies a wall of the cooling unit and a wall of the air chamber and which provides a completely enclosed heat trarisfer chamber containing a liquid of a particularly 00 desirable type. One form of such construction is exemplified in Figs. 10 through 15, though it is to be understood that this feature as broadly : contemplated by the invention is adapted for use in refrigerators wherein the air chamber, the 0. trays therein, the cooling unit, the freezing unit, etc., are of any well known or suitable type. In the present exemplification the chamber 78 is nearly filled with a liquid 104 which has a freezing point lower than the temperature at the wall 70 of the cooling unit and which has a large change in specific gravity between the normal upper temperature in the air chamber and the normal temperature of the freezing unit, For instance, when SOj is the gas utilized in the freezing unit, 75 the liquid 184 should have a freezing point lower than 14° F. and should have a high degree of change in specific gravity between this temperature and 50° which embrace the normal temperature range of the air chamber. The liquid utilized should likewise be one which will not 6 corrode the walls of the chamber, and, preferably, one which is relatively non-explosive so that it will not be dangerous if any leaks in the chamber should occur during operation.

Ethylene glycol (which is readily obtainable 10 on the market as under the trade name “PrestOne”), either alone or in admixture with water, is particularly desirable for this use. Pure ethylene glycol has a low freezing point (10° to 42’ F.), has a change in specific gravity with 15 temperature which is about twice that of water at ordinary refrigeration ranges, is a non-electrolytlc compound which will not attack metal, and has good surface-wetting qualities which promote the rapid transfer of heat thereto from 20 the back wall of the refrigerator and from it to the cooling unit. As is well known, most mixtures of ethylene glycol and water have a still lower freezing point than pure ethylene glycol,— a mixture containing 3 parts of water and 97 25 parts of ethylene glycol having a freezing point as low as —47° F.,—and have other desirable qualities of pure ethylene glycol in a high degree. In the event that the use of ethylene glycol, or mixtures containing it, is for any reason unde- 39 sirable, various other liquids may be used, as, for example, mixtures of glycerin and water, methyl alcohol and water, ethyl alcohol and water, pure alcohols, diethylene glycol, suitable oils, etc. For instance, a mixture of 70 parts of glycerin and 34 30 parts of water has a freezing point of —38° F. and a good cubical expansion (1. e., a high change in specific gravity with temperature), and a mixture of 71 parts of ethyl alcohol and 29 parts of water has a freezing point of about 44 —60° F. and a good cubical expansion.

In instances wherein more positive means than the members 83 are desired to assure that the trays are properly centered in an inward or in an outward position, these members may be 45 supplemented or replaced by other suitable mechanism. One form of such mechanism is shown in Figs. 16 and 17. In this form of construction the diametric wall of the tray carries an upper sleeve 105 and also a lower sleeve 106 which is in the form of a cam with its upper surface inclined downwardly to the left of Fig. 10. Above this sleeve is a cam member 107 having a similarly inclined lower surface. This cam is vertically keyed on an extension 108 of an u annulus 109 which is fixed to the pivot rod 78. The member 107 is resillently held in a downward position by a spring 110 so that, as the tray is swung toward an inward position, the pressure of the spring on the member 107 will tend 55 to center the sleeve 106 so as to bring the right and left-hand edges of the tray flush with the normal base of the refrigerator. In order to hold the trays in a fully accessible outward position, the sleeve 106 is formed with a detent III 45 in which the lowermost point of the member 107 fits, as shown in Fig. 17, when the tray is in an outward position. It is to be noted that as soon as the tray is given a slight movement inwardly, the cam member 107 under the influence of the 70 spring 110 will swing the tray around to a fully inward position.

A distinctly annoying feature in present-day automatic refrigerators is the necessity for defrosting at frequent Intervals. The construction 74

2,130 shown in Figs. 10 through 15 eliminates all necessity of defrosting, since even if the liquid

104 reaches a temperature so that frosting will occur, the frost will disappear when the liquid returns to its normal higher temperature.

In many Instances, however, it is desirable to maintain a low temperature in the ice-cube chamber for a long period of time, as throughout a hot summer day to provide ice cubes in 10 quantity, and the invention contemplates the provision of a refrigerator wherein ice cube production may be maintained as desired without unduly cooling the air chamber of the ref rigerator and without tendency toward undesirable freez15 ing of the contents of the air chamber.

In Figs. 18 and 19 there is shown a modified form of the construction shown in Figs. 10 through 15, wherein such results are accom-^cplished. In this construction insulating walls 20 and 113 are provided to divide the heattransfer chamber 73 into a liquid-containing chamber 114 about the ide-cube compartment and the expansion unit, and a liquid-containing chamber 115 at the rear of the trays. Conduits 25 116 and f 17 are provided for connecting respectively the tops and bottoms of the chambers thus formed, to provide for the circulation of fluid. A portion of the chamber i 15 extends under the bottle compartment, as shown at 116α.

Ip the conduit 117 there is provided a valve unit 118 which includes a thermostatic device of any well-known or suitable typer disposed in the fluid contained in the chamber 115. This valve is normally arranged to be closed and is arranged to 35 be opened ofily when the temperature of the liquid in the chamber 115 rises above a degree at - which it should efficiently cool the air chamber ' containing the trays. If ethylene glycol or other low-freezing-point liquid is used, the temperature 40 in the chamber 114 and within the ice-cube compartment may be kept well below the freezing point for a long period of time without cooling the air chamber to a point where the contents will be frozen. >

.. This feature of the invention is applicable to a wide variety of types of refrigerators.

There is exemplified in Figs. 20, 21 and 22 a conventional automatic refrigerator constructed to embody this feature. The refrigerator includes an insulated casing I i 9, an insulated door 120, stationary trays 121 in the refrigeration chamber, compressor and pump unit 122, condenser means 123, and. an expansion unit 124 carrying an ice-cube compartment 125 in which ice-cube trays 126 are contained, all of conventional construction. An insulating wall 127 provides a chamber 128 for maintaining a heattransfer fluid in contact with the cooling unit 124 and about the ice-cube compartment 126. 60 At the back of the refrigerator there is installed a plate 129 which is bent out so as to provide, in conjunction with the rear wall of the refrigerator, a chamber 130 in the form of a long continuous conduit. This conduit communicates 05 with the top of the chamber 128 at 131 and with the bottom of the chamber 128 at 132 through the medium of a pipe 133 so that the whole provides a heat transfer chamber 134. A valve unit 135, whichjs thermostatically controlled by any 70 well known or suitable means in response to the air In the tray compartment, controls the flow between the division 128 and 130 of the chamber 134. The slightly chilled ethylene glycol or other fluid in the chamber 128 is admitted to conduit 75 130 only when the temperature in the air cham',441 5 ber rises to an undesired degree. Otherwise the low temperature liquid in the chamber 128 acts to assist in the rapid freezing of water in the icecube trays. Means such as are commonly employed in automatic refrigerators or other suit- 5 able means to expedite or reduce the freezing action may be employed. Such means may consist of a control lever 136 which may be suitably connected with conventional control means.

The feature of the Invention here under con- 10 sideration is adapted for use not only in socalled “automatic” refrigerators, but also m refrigerators Wherein the cooling unit embodies a replaceable cooling medium which acts at a low temperature: since, as will be apparent, the 15 advantages of maintaining a freezing chamber at a particularly low temperature and a refrigeration chamber at a relatively higher temperature will be present regardless of the type of low temperature cooling unit used. For instance, a 20 dry-ice compartment may be utilized as the cooling unit in a construction such as shown in Figs.

and 19 or Figs. 20 through 22.

It will thus be seen that there may be provided in accordance with the invention refrigerators 25 embodying one or more of several highly desirable features which make for efficiency, accessibility, convenience, and freedom from various drawbacks in the types of commercial refrigerators commonly provided for automatic used. 30

The invention accordingly comprises an article of manufacture possessing the features, properties, and the relation of elements which will be exemplified in the article hereinafter described and the scope of the application of which will 35 be indicated in the claims.

It is also to be understood that the following claims are intended to cover all the generic and specific features of the invention herein described, and all statements of the scope of the ₄® invention which, as a matter of language, might be said to fall therebetween.

Having described my invention, what I claim as new and desire to