US2132879A - Mechanical refrigerator - Google Patents

Description

G. POWNALL 1 2,132,879 MECHANICAL REFRIGERATOR Oct. 11, 1938.

Filed Sept. 9, 1935 2 Sheets-Sheet l INVENTOR.

Y GEO/f6 L Paw/m Patented Oct. 11, 1938 UNITED STATES PATENT FFICE 14 Claims.

The present invention relates to mechanical refrigerators and particularly to improvements in the means of producing small ice portions therein and also to the concomitant production of improved conditions in the food storage compartments of mechanical refrigerators.

In the art pertaining to the production and use of modern mechanical refrigerators of whatsoever sort, it has become patent that the dry cold atmosphere in such refrigerators dehydrates food stuffs, necessitating the storage of most food stuffs in covered containers, and that in addition to this, odors and tastes of foods so stored are present in the small ice portions formed in the refrigerator. It has also been scientifically determined that perishable food stuffs deteriorate and decay more so in covered or sealed containers than if allowed to remain in contact with pure circulating air, the temperature conditions being 20 uniform in both cases. This is due to the fact that all fresh food stuffs undergo a constant decomposition, thereby yielding gaseous products of decomposition which, if condensed in the presence of the food stuffs, cause a more rapid decomto the purifying effects of a fresh supply of suit ably humidified air and oxygen. This is particularly true of food stuifs having a delicate aroma characteristic of such food stuffs, in their fresh 30 state.

An object of the invention is to provide a means whereby small ice portions may be quickly frozen in a mechanical refrigerator.

Another object of the invention is to provide a means whereby clear small ice .portions may be frozen in a mechanical refrigerator and whereby at the same time, the humidity of the atmosphere in the refrigerator is increased thereby absorbing the escaping gases of the foodstuffs and 40 materially purifying the atmosphere.

Another object of the invention is to provide means to circulate humidified washed air to a refrigerator regardless of whether ice is to be frozen therein or not. 1

Another object of the invention is to provide a refrigerator tray system whereby clear, odorless and tasteless small ice portions may be formed, said system including a means in the refrigerator for venting the refrigerator of its gases under certain conditions. Another object of the invention is to provide the so-called ice trays for producing cylindrical small ice portions of either opaque or clear ice characteristics and for producing these with maximum emciency.

These and other objects are attained by the position or decay than when the food is subjected Fig. 2.

means and method herein described and disclosed in the accompanying drawings, in which: v

Fig. 1 is a vertical sectional view of a mechanical refrigerator embodying one form of the invention.

Fig. 2 is a perspective view of an ice portion freezing tray of the invention, part being cut away.

Fig. 3 is a top plan view of the tray shown in Fig. 4 is a view taken on line 4 4 of Fig. 3.

Fig. 5 is a view taken on line 55 of Fig. 3.

Fig. 6 is a fragmental plan view of an ice cube freezing tray of the invention.

Fig. 7 is a fragmental plan view of a tray 15 adapted for the quick freezing of cylindrical opaque small ice portions.

According to a preferred embodiment of the present invention, the so-called ice trays are provided in an arrangement whereby heat transfer is effected on substantially all sides of the confined bodies of water to be frozen and, in addition thereto, quickly adaptable and detachable means is provided whereby air under suitable pressure is bubbled through the individual bodies of water to be frozen, to the end that clear ice portions are :formed. By this means there is also effected a circulation of air that is of greater humidity content than normally found in mechanical refrigerators and this humidified air absorbs a greater quantity of the gases of decomposition present thereby minimizing the opportunity of contaminating the more delicate foods with the taste or odors of the foods having more pronounced or stronger odors or flavors. The novel features and advantages, however, are not confined to those heretofore enumerated, such additional features and advantages being hereinafter more fully set forth.

The mechanical refrigerator may be of any ap- 40 proved design and may consist of the usual insulating outside casing wall In which is, according to the preferred form of this invention, provided with a pressure responsive relief valve I I that may be mounted within the heat insulating sleeve 12. Any suitable source of compressed air, as from a pressure supply chamber [3, is connected by a suitable tube or pipe I 5 through a heat insulating bushing l6 into the interior of the refrigerator and 'there connected with a pressure header pipe l'l. Chamber 13 may be fed by any suitable means (not shown) but which may be operated by the compressor motor for the refrigerating unit. The pipe I!- is provided with connector members II, the openings of which are disposed 66 respectively at levels slightly above the water levels of the ice-freezing trays indicated generally as IS. The connectors are provided with suitable self-closing valves which may be of the ball check type. The refrigerating unit may be of any type of approved design employing the usual refrigerant coils 2| which surround the freezing unit in the refrigerator and which are provided, especially in the upper tiers, with tray supports or shelves that may be constituted principally by spaced transverse members 22.

The ice trays in preferred embodiment (see Figs. 2 to 5 inclusive) may be made of any approvedmaterial, i. e. either metal or preferably semi-flexibie rubber or made up of a plurality of cylindrical vertical tubular molds 23 connected tangentially as at 24 and thereby providing a maximum of surface'over which the cold air may pass. The spaces between the interior sides on interior rows of molds 23 are entire'iy open as can be seen at 25 (Fig. 3) and this allows the free circulation of cold air through all tiers of trays and substantially all surfaces of each mold in each tray. The so-called ice freezing compartment 26 which the trays are disposed may be of the isolated type or not, according to the design of the refrigerator. As shown in Fig. 1 the ice freezing compartment is enclosed within a housing 2'! having an access door 28' in the front thereof and being surrounded on its top, bottom and sides by the refrigerating coils 2|; The customary refrigerant supply chamber 29 in circuit with the compressor (not shown) and refrigerant coils may be located at any convenient place in the refrigerator, for example above thefreezing coils 2| as shown in Fig. 1. Referring now to Fig. 2, it will be noted that at the rear of each tray there is provided a cross member 30 which is vertically cored as at 3i and which has projecting from the top thereof a tapered elbow connector 32 that is automatically centered and entered into the valves 25 when the tray is pushed into place inthe ice freezing unit, and it automaticaily unseats the check valve 20 thereby affording pressure air supply to the cored passages in the tray. These cored passages or air lines are conveniently disposed one each in longitudinally extending ribs 33 beneath the rows "of ice molds, the passages 34 each having vertical connection as at 35 with the interior of the individual molds 2-3 at the bottom thereof. A

suitable handie 36 serves both as a handling member and as a. bridgeway member to strengthen the connection between the molds of the endmost row at the front end of the tray. As may be readily seen in Fig. 2 the air passage 3| in the member 30 connects with a transverse passage 36' near the bottom of said member and which communicates with the passages 34 in ribs 33. While the means for providing agitating air in each individual ice mold is shown as an arrange ment at the rear of the freezing compartment and the trays, it is not of necessity so disposed, it being feasible, and in some cases perhaps preferable, to arrange the automatic air supply and connecting means at one side to the front of the tier of trays so that, upon the final movement in inserting and upon initial movement in removing a tray, the elbow connector 32 may be visibly guided into the frictional binding connection with the receiving opening associated with valves 20.

In providing for the rapid freezing of clear, transparent ice portions, it is not essential to use the preferred cylindrical molds since any arrangement of molds of whatever cross section combination of maximum cubic content within an allotted space.

The device fragmentally shown in Fig. 6 shows an embodiment wherein the inner rows of molds.

are tangent throughout all sides with adjacent molds but which are provided with pressure air supply agitating the water to be frozen for providing transparent tasteless and odorless table ice portions. In this embodiment the molds 31 are illustrated as of the conventional cubical type but are provided with the identical pressure air supply means that is shown and explained in connection with Figs. 1 to 5 inclusive, these means being similar and identified by like reference characters.

Fig. '7 shows a fragmental plan view of an improved form ef ice freezing tray, the structure being made up of a connected series of transverse and longitudinal rows of substantially cylindrical tube-like molds 38. This tray is adapted for'use in the well-known existing types of mechanical refrigerator and embodies the advantage of quick freezing of ice but does not contain the structure enabling the production of transparent, tasteless and odorless ice and does not provide further features of humidification and purification of the air in the food compartment.

As to the highly advantageous coincidental feature of improving the conditions within the food compartments of the refrigerator while producing transparent,'odorless and tasteless ice it is to be appreciated that the quick freezing of transparent ice may under some conditions be carried on advantageously in refrigerators that are not intended forthe preservation of food stuffs but which are adapted solely to the production of small table ice portions. It is also to be appreciated that the production of transparent, tasteless and odorless table ice portions is not absolutely necessary in a refrigerator for the preservation of food stuffs since an auxiliary humidifying and air purifying unit of a somewhat larger scale may be utilized independently of the ice freezing trays in order to attain these advantages. It is considered however, to be most advantageous to produce transparent and evil of placing such perishables in closed con tainers.

By utilizing the form of quick shown in Figs. 1 to 5 inclusive, and by allowing the presently required amount of time for the freezing of ice, it is possibie to employ the higher safe temperatures for food preservation and thereby minimize the moisture removal or dehumidification process which has been a necessary function of mechanical refrigerators in the past.

It is to be noted that when an isolated or en closed ice freezing chamber is used in a mechanical refrigerator, according to this invention it is freezing trays highly desirable to provide a pressure relief valve 39 in the wall of the compartment 26 so that upon building up of slight abnormal pressures, a humid washed air is vented to the interior of the food compartments and, being somewhat colder than the warmest atmosphere in the refrigerator it will descend and absorb the rising and warmer gases of decomposition from the foods. When an abnormal pressure is developed generally in the interior of the refrigerator it is released by the opening of the pressure active valve During the freezing of each and every ice portion, there is a constant admission of warmer fresh air by way of the pressure source l3 and the agitatingair channels. The'operation of the device is as follows:

Fresh air under pressure is maintained in the header l1 at'all times when the refrigerator is in normal operation. The usable pressure would be from fractions of an ounce toseveral ounces depending to some degree upon the depth of the ice molds in the trays. Assuming that all of the ice trays had been momentarily removed for harvesting the ice and refilling with fresh water to be frozen, each of the valves 20 would be closed so that no air pressure would be lost. As each tray is filled and then moved fully into the ice freezing compartment, the end of the connector 32 is automatically guided into the opening in members I8 and, as the tray is forced to the extreme rear limit the member 32 unseats valve 20 and opens communication between the pressure header and the communicating cored passages in the tray. Air then bubbles through the water in each individual mold throwing out of suspension all impurities and inert matter in the water according to known principles in commercial ice manufacture. This, upon complete freezing of the individual bodies of water, remains as an opaque frost or topping containing all of the impurities and, during the normal washing with warm water and thawing incident to the removal of the ice portions it becomes liquefied and washes away in the warm water bath. Except for the agitation of the water in the molds during freezing, some of the decomposition gases present may combine with the gaseous portion of the water and, in many cases, it is definitely possible to taste and smell the presence of decomposition gases in still water.

If too low a temperature is maintained throughout the refrigerator the circulation of the air is minimized thus allowing the absorption of odors in the more delicate and susceptible food r stuffs.

When the refrigerator compartment is fully enclosed, the valve 39 and II respectively, function to release excess pressure in the refrigerating compartment and the interior? of the refrigerator generally. When the ice freezing compartment is not of the enclosed ty e the necessityfor valve 39 or its equivalent would be eliminated. The valve in II or its equivalent is preferably disposed at some higher elevation in the invention herein, in its preferred form, will provide, in addition to the relatively constant tem perature now attainable, the heretofore unattained requisites of proper humidity, circulation and purity of air. The maintenance of proper temperature alone is not suflicient for the healthful preservation of foodstufis. Inasmuch as foodstuffs is composed of a large proportion of water, the dehydration thereof in present day mechanical refrigerators results in the loss of some of its flavors and natural aroma. The dormant water in the ice molds of the ordinary mechanical refrigerator picks up much of the odors and gases given up by the foods and these are retained in the water in its frozen form under heretofore used conditions.

All of the previously experienced difficulties with mechanical refrigerators are eliminated through the deviceof the present invention, and it is to be understood that the apparatus is useful to provide a proper circulation of clean washed and humidified air for the proper preservation of food stuffs regardless -of whether the cooling coils attain temperatures for freezing ice. To this end, in order to provide, in a general purpose mechanical refrigerator, a means to wash and humidity the air independently of the freezing of ice in the trays, a branch pipe 40 is connected interiorly of the casing to the pipe l5, thereby directing the low pressure air supply to the interior of a water container 4| which is located in any place. convenient for filling and where the water therein cannot freeze under any ordinary conditions. -A check valve 42 is disposed in this branch pipe 40 above the water level of the container 4|. The air check valve 42 allows one way passage of air from the source to the container and it is desirably responsive to a pressure that will allow air to pass and bubble through the water in container 4| only when ice has frozen solid in the ice trays, or when the ice trays are removed. It will be understood that in desired embodiments the structure suggested by container 4| and its air supply may be used without ice freezing trays and that in a cabinet intended solely for ice freezing the characteristic tray structure and air supply would be used.

What is claimed is:

1. In a mechanical refrigerator the combination with a refrigerating unit adapted to receive ice-freezing trays, of an ice-freezing tray having air passages therein discharging into the mold spaces thereof, a connector on said tray incommunication with the air passages, a compressed air supply header having valve controlled openings to receive the connector on said tray and a source of compressed air supply connected to said header.

2. In combination a refrigerator, a pressure relief valve in the wall thereof, a refrigerating unit in the refrigerator adapted for the reception of ice-freezing trays, an ice-freezing tray having air passages opening into the spaces receiving water to be frozen, pressure air supply means and means on the tray connectible with said air pressure supply means.

3. An ice freezing tray comprising a multiplicity of substantially cylindrical molds for receiving water to be frozen, said molds being tangentially connected from top to bottom each with adjacent molds and forming openings extending entirely through the spaces between said molds.

4. An ice freezing tray comprising a multiplicity of longitudinal and transversely aligned and connected molds, hollow rib-like members forming a passage therethrough communicating with the hollow ribs, and an L shaped tubular con-f hector mounted in said cross member and hollow cylindrical molds providing exposed exterior wall surface save at such integral tangential connecting portions, hollow ribs extending beneath selected rows of said molds and forming a distribution system for compressed air, the bottoms of said molds having cored passages therethrough communicating with the interior of the adjacent hollow rib, a cross member con-.

nected to an extreme row of said molds and havadapted for removable connection with a source of pressure air supply.

6. In a mechanical refrigerator the combination of a door-controlled ice freezing compartment, tray supports in said compartment, ice

freezing trays guidedly insertable into said compartment on, said supports, a pressure air supply header mounted adjacent said compartment and having valve-closed openings therein at approximately the top levels of said trays in said compartment, the proximate wall of said compartment being apertured in alignment with said valve-controlled openings, said trays having cored passages therein, a; connector on each tray communicating with said cored passages and-adapted, upon insertion into said compartment to project through the aperture in said wall and to be guided thereby into the adjacent valve-controlled opening in the header, a pressure relief valve in the wall of said refrigerator and means providing pressure air supply to the header.

7. In a'refrigerator the combination of a wall structure forming an enclosed chamber, a cooling means in said chamber hermetically isolated from the interior of the chamber, means to controllably introduce atmospheric air to the interior of the enclosed chamber, and an air pressure relief valve in said wall structure adapted to vent the gases from said chamber.

8. A refrigerator comprising a door-controlled refrigerating compartment, an air pressure into the interior of the refrigerator, a relief valve operative between the interior and exterior of the refrigerator, and means for selectively introducing atmospheric air into said refrigerating compartment and to the interior of the refrigerator.

9. In combination a refrigerator casing, a pressure relief valve in the wall thereof, a refrigerating unit in the casing adapted for the reception of ice freezing trays, and means comprising a source of atmospheric air under pressure and a conduit system leading therefrom to the interior of the ice-freezing trays whereby to attain selective circulation of humidified atmospheric air in the refrigerator casing.

10. An air conditioned mechanical refrigerator comprising a refrigerator cabinet, a refrigerator unit for cooling the interior of'the cabinet, a reservoir for containing water, means to pass atmospheric air through the Water for circulation interiorly of the cabinet, and a pressure relief valve in the cabinet wall.

11. A mechanical refrigerator comprising an ice freezing compartment within the interior of a refrigerator cabinet, an access door to the ice freezing compartment, means to supply atmospheric air to the said compartment, a pressure relief valve in the wall of said compartment I leading to the interior of the refrigerator cabinet, a pressure relief valve in the wall of the cabinet leading to the exterior thereof communicating with the outside atmosphere.

12. As a humidifying device, a unitary removable ice tray for a mechanical refrigerator comprising a multiplicity of ice mold members arranged in longitudinal and transverse rows, and means integral with the tray providing passages for the discharge of air under pressure through the interior bottom of each of said molds, said means adapted for connection with a source of air pressure supply.

13. In a mechanical refrigerator, the combination of an enclosing wall structure, independent cooling means housed by said enclosing wall structure, a watercontainer, means to force atmospheric air through said container and into the interior of said refrigerator, and an air pressure relief valve in said enclosing wall structure.

14. An air humidifying device for a mechanical refrigerator comprising an ice tray having a multiplicity of independent ice mold members, and means integral with the tray providing air passages to the interior bottom of each of said mold members,- and a connector on said tray communicating with all of said passages.

GEORGE L. POWNALL.

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