US2405834A - Device for freezing foods - Google Patents

Description

H. W. KLEIST DEVICE FOR FREEZING FooDs Aug. i3, 1946. 2,405,834

Filed-Dec. 29, 1941 5 Sheetsf-Sheet 1 .LNA

Aug@ 13 3946 H. w. KLEls-r 2,405,834

DEVICE FOR FREI'IZING FOODS i Filed Deo. 29, 1941 3 Sheets-Sheet 2 a F572' 39 3.9 V A 29 jerffzasn if jZezLvSt Aug. 13,L 1946.

H. w. KLEIST DEVICE FOR FREEzNG FooDs 3 sneets-sheet s Filed Dec. 29, 1941 Patented Aug. 13, 1946 Unirse sr naar DEVICE Fon FREEZING Foons ration of Illinois Application December 29, 1941, Serial No. 424,741

2 Claims.

Ihis invention relates to devices for freezing foods and has for its object to provide a new and improved device of this description.

The invention has as a further object to provide a device for freezing foods by means of conduction combined with air circulation. f

The invention has as a further object to provide a device for freezing foods by means of which the time required for freezing is greatly reduced.

The invention has further objects which are more particularly pointed out in the accompanying description. f

' Referring now to the drawings, Fig. 1 is a vertical sectional view through one form of device embodying the invention;

Fig. 2 is a sectional view taken on line 2 2 of Fig'. 1;

Fig. 3 is a sectional view through a plate nipple for use in removing air from between the plates;

Fig. 4 is a view of one of the plates with a portion of one sheet broken away;

Fig. 5 is a view similar to Fig. 1 showing a modied construction, where the food is located in a separate freezing chamber.

Fig. 6 is a sectional View taken on line 6 6 of Fig. 4.

Like numerals refer to like parts throughout the several figures.

Referring now to the drawings, there is illustrated a cabinet or receptacle I, provided with a plurality of refrigerating plates 2, 2a, 2b, 2c, etc. These plates are vacuum plates and are`made up of `two comparatively thin metal sheets 3 and 4. Located between these sheets is a pipe 5 formed into a coil. extending back and forth between the sheets. The sheets are hermetically sealed at the edges so as to form an air-tight receptacle. The pressure of the air on the inside of this receptacle ls reduced so that the greater external pressure causes the sheets'to make good heat conducting contact with the pipe 5.

For'this purpose, some means is provided by .means of which air may be removed from between the sheets 3 and il. As herein shown, a nipple 'I is provided which has a passageway 8 connecting with the interior of the space between the sheets S and 13. There is a check valve 9 for closing this passageway. Above the check valve 9 is an enlarged part ie which has an internal screw thread. An air removing device is connected with this enlarged portion so that sufcient air may be withdrawn from between the sheets 3 and il to secure the desired pressure Contact between the sheets 3 and l and the pipe 5. The check` valve 9 opens to permit the air to be withdrawn and closes when the air withdrawing device is disconnected. There is` a plug H screwed into the nipple 'l which closes the connection so as to prevent the air from entering,v thereby causing the lower pressure within the plate to be maintained.

The above described structure is particularly advantageous for the use of plates partially filled with a eutect'ic solution. With referencefor example to Figures 3 and 6, when the plug il is initially removed and the ball raises, any suitable liquid may be poured into the plate space through the passage 8 until the space between the plates is partially filled. IThereafter the ball 9 or its' equivalent is positioned in place and the space between the plates `which contains eutectic solution is partially exhausted and the plug ll is returnedy in place; The ball 9 then serves as a check valve preventing the entry of air into the evacuated interior of the plate.

The plates 2, 2a, 2b, etc., are mountedA in any desired manner. As herein shown, these plates kare preferably mounted in a horizontal position.

The plate 2 is preferably arranged at the top of thereceptacle. The plates 2a, 2b, etc., are preferably arranged so that the food to be frozen may be placed on top of these plates. The plates `are also preferably arranged in staggered relation. There are spaces I2, I 2a, |2b, I2C, i242, etc., above the plates. These spaces are preferably of different heights to permit food material of different heights to be placed therein and still have a space for the circulation of the cold air. These spaces are preferably arranged to form a continuous passageway. The space l2 is connected at one end with the space l2a by the opening i3; the space I2a is connected at the other end to the space |213 by the opening Hl; the space i211 is connected at its other end by the opening i 5 with the space I2C; the space I2C is connected at its other end by the opening I6 with the space i203; the space I2d is connected by the opening il with the space I8; the space I8 is connected by the opening l5 with the passageway 2G extending along one end of the receptacle i and this passageway is connected to the space l2 between plates 2 and 2a by the opening 2l. An air moving device 22Vis preferably arranged in the opening 2l and is operated by a motor 23. The passageway 20 is bounded by the end wall of *he receptacle l and the plate 20a.

The plates 2, 2a, etc., are connected to a refrigerating apparatus 245 of any of the usual types containing a compressor 25, a condenser 26 and a motor 2l for operating thefcoinpressor. A pipe 28 leads from the condenser to one of the plates,

as for example, the plate 2. There is the usual expansion valve 29 in this pipe. The pipe 23 connects with the pipe in the plate 2.

The pipes 5 in the different plates are connected together so that the refrigerant may pass through the pipes 5 in all of the plates. As herein shown, these connections are made by the pipes 35, 3|, 32, 33, 34 and 35.

There is preferably a storage compartment 36 separated from the receptacle I and in which foods may be stored after they have been frozen. There is a plate 2f in this storage compartment and the pipe 5 of this plate is connected by the pipe 35 to the pipe 5 in the plate 2c. The plate 2f is connected by pipe 31 with the compressor 25.

While the plates may be suspended in any desired manner, I have provided a simple, cheap and effective means for accomplishing this. In this construction, one of the sheets of which each plate is made is larger than the other so as to provide a projecting edge 3a. Angle irons 39 are placed on the wall of the receptacle I and the plates are supported on these angle irons by means of the projecting edges 3a (see Fig. 2).

The refrigerating apparatus 24 may be located in any place desired. It would ordinarily be located outside of the receptacle I and the storage compartment 38 and would usually be located in the basement of the building.

In Fig. 5 I have shown a modified construction. In this construction the cabinet I is provided with a plurality of refrigerating plates 2, 2a, 2b, 2c, etc., with spaces between them, and an air moving device 22 to move cooled air back and forth through the spaces between these plates.

These plates are connected to the refrigerating apparatus in the usual way, as shown in Fig. 1. This construction is particularly adapted for use in connection with ice cream. The ice cream, in this case, is not frozen or kept frozen on the plates, but is placed in the storage compartment 36a.

In this construction, instead of having the cool air pass under the plate 2e, it is directed from the passageway IT through an opening 4I! in the partition 4I and passes into the freezing chamber or chambers 35a so that the material to be cooled therein is immersed in the cold air and this cold air then passes up through an opening 42 in the partition l!! and thence along the passageway 20 back to the air moving device 22. By means of this construction the air is cooled to a very low degree as it passes between the plates and then this cold air, the temperature of which may be below the freezing point, passes into the l freezing chamber so as to freeze the material therein. When it is such material as ice cream, the ice cream can be kept at the proper desired temperature.

'I'he speed of the air moving device 22 may be varied to move the air at a slower or faster speed, depending upon the cooling condition desired.

By having the plates smooth, it is not necessary to defrost the device as very little Vfrost will deposit on the plates and Whatever does deposit can be easily and quickly scraped off while the refrigerant is `being passed through the plates.

By means of the air moving device the temperature in the freezing chamber may be reduced to from to 30 degrees below zero.

Access may be had to the receptacle I by means of doors 43 and access may be had to the storage chamber 35 or 36a by means of doors 44.

The operation of the invention isas follows:

When the device is to be used, the food to be frozen as shown in Fig. 1 is placed on the plates 2a, 2b, 2c, etc. The refrigerant is circulated through the pipes 5 of these plates by means of the refrigerating apparatus 2a so as to cool the plates down below freezing. YThe air moving device 22 is operated and the cold air is circulated back and forth between the plates and above the food thereon, and when it reaches the bottom plate this cold air passes through the opening I9, up into the passageway Ell and back to the air moving device 22.

'Ihe food is frozen by contact with the plates and is also frozen by the cold air striking the food as it is circulated by the air moving device 22, In Fig. 5 the cooled air which is circulated between the plates is then discharged into and circulated through the storage chamber 36a.

I have found that by means of the simultaneous cooperative action of the freezing plates and the circulating cooled air the time required to freeze the foods is decreased very materially, and I have found this decrease in freezing timel to be from 30 per cent to 50 per cent depending upon the food frozen.

After the foods are frozen they are removed from the plates and placed in storage chamber 3B, and other foods placed on the plates and frozen. This device, therefore, very greatly increases the efficiency in freezing foods by thus decreasing the time it takes to freeze the foods soi-.hat a much larger quantity of food per day can be frozen and placed in the storage device. It is of course evident that a series of storage devices may be used in order to take care of the food frozen on the plates in the receptacle.

By providing a clearance between adjacent plates which decreases progressively toward the air discharge end of the series of plates, I cause a progressive increase in the speed of movement of air between the plates, and also compensate for the volumetric change due to progressive cooling of the air. The use of the above described arrangement economizes on space. Small packages placed between the closer spaced shelves are more rapidly frozen, being subjected both tothe action of the plate on which they rest and to the action of the closely spaced shelf above.

I claim:

l. In a freezing and storage assembly for frozen foods and the like, a quick freezing compartment and means for quick freezing material inserted therein, including a plurality of vertically spaced generally horizontal cold plates arranged in staggered relation and adapted to form, with the walls of said compartment, a devious path for air, each said plate including upper and lower smooth surfaced metal sheets, whereby the passages defined between adjacent cold plates have smooth upper and lower walls, means for circulating a volatile refrigerant through said plates, and means, arranged to cooperate with said plates, for circulating air along the path defined by said plates, and an additional storage chamber having an air passage connection adapted to admit air from the quick freezing cabinet, and an air discharge connection adapted to return used air to the air circulating means.

2. In a freezing and storage assembly for frozen foods and the like, a quick freezing compartment and means for quick freezing material inserted therein, including a plurality of vertically spaced generally horizontal cold plates arranged in staggered relation and adapted to form, with the walls of said compartment, a devious path for air, each said plate including upper and c. 5 lower smooth surfaced metal sheets whereby the passages defined between adjacent cold plates have smooth upper and lower walls, means for circulating a volatile refrigerant through said plates and means arranged to cooperate with said' plates for circulating air along the path defined by said plates, and an additional storage chami ber having an air passage connection adapted to HERMAN W. KLEIST.

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