US1822851A - Refrigerating apparatus and method - Google Patents

Description

Sept. 8, 1931. c. L. JONES REFRIGERATING APPARATUS AND METHOD Filed March 25 1950 Mmuopm@ Q l? f f. n 7 .Im f 4 X5 if??? L mi@ l WM m l A r Patented Sept. 8, 1931 UNITED STATES 'y PATENT oFFlcE A CORPORATION oF DELAWARE REFBIGERATING APPAEATUS METHOD 3, Application led Hatch 25, 1930. Serial No. 438,704.

This invention relates to apparatus and methods for refrigeration by evaporation of solidified carbon dioxide and more specifically to refrigerators wherein ducts, hollow Walls or interspaces are employed to circulate the resulting cold carbon dioxide gas, or mixtures thereof with air, in heat exchange relation with the space or products to be refrigerated.

A primary object of the invention is to produce a more uniform temperature throughi, out the refrigerated space or product, particularly as between the upper and lower re.- gions thereof. As is well known, the upper regions are likely to be too warm and the lower regions too cold, because, although the gas is usually evolved in an upper region of the refrigerator, it tends to flow downward in the ducts or interspaces before it has time to edectually refrigerate said upper region.

Hence one feature of the invention involves retaining the freshly evolved gas in vheat exchange relation to the upper portion A designed to form olie or many rpools ofthe down-flowing gas, thereby more or less interfering with the natural top-to-bottom circulation.

A still further object is to provide means whereby, particularly in an ice cream dis.

pensing or freezing apparatus, the upper portion of the refrigerated chamber or product is etfectually refrigerated first, by retaining the down-flowing gas in a series of pools at desired levels, the upper leaking or cascading into the lower. In an ice cream dispenser, this permits the upper parts ofthe ice cream, which are most exposed in use, to be maintained at the proper temperature,

while unnecessary over-freezing of the lower portion of the product'may be avoided.

The above and other features of my invention may be more readily understood from the following description in connection with is shown as embodied in a conventlonally ine dicated refri erator which may be somewhat. like those shown in Martin Patents Nos. 1,752,015, 1,752,276 and 1,752,277, and somewhat resembling the construction shownin Fig. 7 of the latter; but with the important difference that, as explained below, the

`CHARLES L. JONES, 0F PELHAM, NEW YORK, ASSIGNR T0 DRYICE EQUIPMENT CQB.-l v

` POBATION, 0F NEW YORK, N. Y.,

thermo circulation is greatly modified. The

outer casing 1 may be of any known or desired heat insulating construction, tommonly employed for refrigerators. Within'the same is a Container 2, preferably of sheet metal, of proper size to leave interspaces for circulation of gas in the spaces 4, 4a and 4b,

which are preferably sealed off from the in,- terior refrigerated storage space 5, and as in said Martin patents, any side opening doors for access to this space" will have the'sheet metal container 2 carefully sealed, gas-tight about the doorwa s. In an upper portion of this container in eat exchange relation with the interior and in gas circulating relation to the interspace, is formed a container 3 for the solidified carbon dioxide.

'The peculiarity of the arrangement is that this latter has an upwardly extending wall 6 which prevents the gas evolved in 3 from overflowing directly into the interspaoe 4b. Consequently, the freshly evolved gas must ow across the roof or ceiling 7 of the refrigerated space before it flows down through 4. Further and more important, there is an upstanding ledge or retaininu wall 8 in the nature of a balile or dam, y tial layer of the freshly evolved gas is retained in Contact with said ceiling 7 until the whereby a substanadded supplies of gas from 3 force overflow into downflow duct 4. Thence it iows across the bottom 4a and eventually up through 4b. At the top, part of the gas may recirculate -through the opening 9, the excess escaping either through leaks in the cover or through an overflow duct 10. v

While the freshly evolved gas tends to iow in the path described, it will be noted that the lefthand wall of the container 3 for the-solidified carbon dioxide is in heat ex the duct 4 and across beneath the cover of the outer casing throu h the opening 9. Preferably, however, t e proportiomng ofthe structure and the How ,section of the passages 4, 4a and`4b will besuch that the circulation will be as first above described, downward through 4, across through 4a and upward through 4b.

If the inner container 2 is spaced apart from the outer casing 1 at front and rear, the front and rear interspaces may constitute the upiiow portions of the circuit, partially or wholly Orvarying from time to time. In fact, the remarkable uniformity of temperatures seems to be due in part at least to the mixing due to reversing tendencies of themocirculation within each part of the interspace.

In most ordinary refrigerator structures refrigerated by water ice or mechanical refrigeration, air is the only gas used in transferrirrg heat, convection currents being usually obtained by thermo-circulation. In such systems the minimum temperature is 32 and the average say 40 F. In such case, the coldest air is only about one-third of one per cent heavier than .the warmest. Hence the thermo circulation'is slow and the difference in temperature between the top and bottom gas having once dropped to the bottom of the space or duct, does not rise again due to subsequent convention currents as readily as will air. Consequently, there is a tendency to a greater difference between the upper and lower regions of the refrigerator in a system using solid carbon dioxide were it not for the fact that suiiicient gas can be sublimated to completely fill the interspaces or ducts surrounding the refrigerator chamber. However, to fill these ducts and maintain them filled requires that carbon dioxide gas be continuously sublimated and of course the more gas required the greater will be the consumption of the refrigerant.

When the gas is first evolved, it'naturally Ais 'coldest and its temperature rises as it circulates through the refrigerating system. By

-my system, this first evolved or coldest gas flow can be retarded or retained in pools so 'that the as may be warmed to a desired extent be ore it reaches the bottom of the structure and may even be warmed enough to start localized reverse upward currents from intermediate levels. Hence the portions of the structure surrounded or bathed in the' cold carbon dioxide gas at the top cannot be warmed by heat from the outside, to a temprature higher than that of the coldest carn dioxide gas. in which the wall is batlfed.

For the average use, it might be undesirable to establish the lowest refrigerating temperatures at the top and build downward, so, while this is possible, I prefer not to completely shut off the bottom portions of the refrigerator chamber, but only toretain desired amounts of the downiow gas, in local refrigerating zones,`at different levels, the amounts and distribution being 'controlled by the design of the gas-retarding means. In

this way, I mayobtain substantially uniform temperatures throughout the entire system or chamber; or any 'desired approximation ofv uniformity. `In some of the tests run, I

-have even maintained a lower temperature at the top than at the bottom, but the usual variance was less than 3 F. between the top and bottom of the refrigerator chamber, the bottom temperature being the lowest.

' The modified arrangement shown in Fig.

2, like all the other modifications shown inl the drawings, is applicable to almostany type of refrigerator, such as the household refrigeratoi of Fig. 1 or in fact any type in commerwalls, are alternating baflles 13. It will be `seen that as carbon dioxide gas is sublimated within the container 9 it will fill up the cnl tainer and flow over the sides 12 into the spaces 10 completely filling said spaces and may be led back to the container 9 or vented to the atmosphere through vents 14. The first gas to be sublimated will be trapped ory retained in pools by the baliles 13 and the pocket formed by the baiiies and the walls from which they extend' will be filled with the cold carbon dioxide gas before any of it is allowed to flow below them, thereby first refrigerating the upper section of the refrigerator chamber and subsequently retaining there the coldest carbon dioxide gas. In a system of this general type, after the ducts have been filled with carbon dioxide gas, the tendency of the gas to sink to the bottom and the function performed baiiies of holding the coldest carbon diox- 1 e gas in the upper'portions will substantially equalize the refrigerating effect` in all parts of the refrigerator chamber, thereby producing an almost uniform temperature throughout the refrigerator chamber. In this arrangement it is clear that natural top-tobottom circulation is broken up, the 'coldest gas tending to cascade downward, while the warmer gas must lind its way upward, countercurrent in intimate mixing as well as heat exchange relation with the downllow.

In Fig. .3 the baflies 15 are shown as extending almost completely across the spaces 16 formed by the walls 17 and 18. These baiiles have, at any desired point therein, the holes or perforations 19 to allow` constant iiowof gas downward while at the same time retalnmg substantially a solid wall of the gas around the upper portion of the refrigerator chamber.

In Fig. 4 the bailles 20 are of different lengths, the shortest one being at the top and .the one next below being slightly longerto catchthe overflow of gas from the one above. Each succeeding baille is slightly longe` than the one above, the bottom one being the longest. A

Figs. 3 and 4 afford better op ortunity for countercurrent up and down ow'with less necessity for mixing than in Fig. 2.

In Fig. 5 I have shown a spiral baille 21 which practically insures heat extraction by the length-of the path that the cold carbon dioxide gas must traverse before reaching the bottom of the ducts. Instead of being an open baile plate as shown, this could be a tube or, if desired, instead of being a spiral it could be disposed in successive circles, each discharging downwardly into the next one below it. Fig. 5 shows vstill better opportun-v different parts tocause greater or less heaty absorption from any one of the walls of the compartment. For instance, the insulation between ythe solid and the lefthand wall of compartment 3 in Fig. 1 could be made very thick, thereby proportionally decreasing the rate of heat absorption from the duct or interspace 4b. i i

I claim: y Y 1A double Walled refrigerator chamber and a container for an intensely cold refrigerant, arranged for circulating cold atmosphere from the refrigerant container between said Walls, and circulation impeding baiiles arranged substantially transversely to the direction of travel of the col atmosphere and between said walls.

2. A refrigerator chamber and a container for an intensely cold refrigerant adjacent the `upper portion thereof; with circulation ing baies arranged substantially transversely 'i to the direction of travel of the cold atmosphere whereby the upper portions of the refrigerator chamber will be refrigerated first.

3. A refrigerator enclosing a solid carbon dioxide container, and downwardly extending circulation ducts into which carbon dioxide gas from said container flows, and

circulationimpeding baflles within said ducts arranged transversely to the direction of flow of the carbon dioxide gas.

4. A refrigerating apparatus enclosing a space to be refrigerated, and including a container of solid carbon dioxide arranged to absorb heat and discharge gas at a high level and ducts for circulation of the gas to cool said space, designed and arranged for retaining a body or bodies of the freshlyevolved gas in heat absorbing relation with a high level portion of said space until said gas is warmed to a desired extent, but permitting overflow of excess gas to a lower level.

5. A refrigerating apparatus enclosing a space to be refrigerated, and including a container of solid carbon dioxide arranged to absorb heat and discharge gas at a high level and ducts for circulation of the gas to cool 'tainer of solid carbon dioxide arranged to absorb heat and discharge gas at a high level and duct-s for circulation of the gas to cool said space, designed and arranged for vretaining a body or bodies of the freshly evolved gas in heat absorbing relation with a high level portion of said space until said gas is warmed to a desired extent, but permitting overflow of excess gas to a lower level, and a series of retaining baies in the path of downiow of said gas arranged for overflow of gas from the higher batlies to the lower ones, and arranged to retard both up and down thermo circulation in said duct.'

-7. A double-walled refrigerating apparatus enclosing a space to be refrigerated, a centaine of solid carbon dioxide arranged to absorb eat and discharge gias at a high level for circulation in the interspace between said walls, the flow paths being arranged for retaining a body or bodies of the fres ly evolved vgas in heat exchange relation with a high level portion of the refrigerated space but permitting voverflow thereof to a lowe level in said interspace. v

8. A double-walled refrigerating apparatus enclosing a space to b e refrigerated, a

container of solid carbon dioxide arranged to absorb heat and discharge 4gas at a high level for circulation in the interspace between said walls, and a series of retaining balies in the path of downiow of said gas arranged for overflow of gas from the higher baiies to the lower ones.

9. A- double-walled refrigerating apparatus enclosing a space to be refrigerated, a container of solid carbon dioxide .arranged to absorb heat and discharge gas at a high level for circulation in the interspace between said walls, and a series of retaining baiiles in the path of downflow of said gas arranged for overflow of gas from thehigherbaflies to the lower ones, and battles arranged to retard both up and down thermo circulation in said interspace.

10. A double-walled refrigerating apparatus enclosing a space to be refrigerated, a container of solid carbon dioxide arranged to absorb heat and discharge gas at a high level for circulation in the interspace between said walls, and baies arranged to hold and permit overow of gas, down flowing adjacent the inner wall' ofthe interspace and-tobringvthe 05 overflow into heat exchange and mixing relation to warmer gas tending to flow upward adjacent the outer wall of said interspace.

11. Refrigerating apparatus, including outer and inner containers' formed and arranged to confine and permit circulation, of gas between 'said containers, in combination with a containei` enclosing solid carbon dioxide arranged so that said solid may absorb heat derived from the inner container and arranged for downflow of the resulting dry cold gas between the containers; and retaining means in the path of downiiow of said gas to establish high level refrigerant zones about sai-d inner container.

' 12. Refrigerating apparatus, including outer and inner containers formed and arranged to confine and permit circulation of gas between said containers, in combination with acontai'n'er enclosin solid carbon dioxide arranged s that sai solid may absorb heat derived fromthe inner container and arranged for downow of the resulting dry cold gas between the containers, and substantially transversely extending baiiies in the path of downiow of said gas.

13. A refrigerator enclosing a chamber to be refrigerated and a solid carbon dioxide container at a high level therein,v and provided with a carbon dioxide gas circulation duct leading from the carbon dioxide chamber and substantially surrounding the refrigerator chamber, a' baiile near the inlet end of said duct whereby carbon dioxide gas is retained in the upper portion of said duct and a vent in said duct at a high level point of the gas circulation.

14. A double-walled refrigerator enclosing a chamber to be refrigerated anda solid carbon dioxide container absorbing heat and discharging gas at a lhigh level therein, and formed or provided with gas circulation space between the walls and with circulation impeding baies alternately arranged on opposite walls of said circulation space.

15. A double-walled refrigerator enclosing a chamber to be refrigerated and a solid carbon dioxide container absorbing heat and discharging gas at a high level therein, and formed or provided with gas circulation space between the walls and with circulation impeding baffles closing most of said space and perforations in said baiies.

16. A double-walled refrigerator enclosing a vchamber to be refrigerated and a solid carbon dioxide container absorbing heat and discharging gas at a high level therein, and formed or provided with gas circulation spacel between the walls and withcirculation impeding baffles extending outwardly` progressively from the upper part of said circula- 'tion space, downward, whereby carbon dioxide gas overowing from one of said baliies will be caught by the next baiiie below.

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17. Adouble-walled refrigerator enclosing I a chamber to be refrigerated and a solid carvbon dioxide container absorbing heat and discharging gas at a high level therein, and formed or provided with gas circulation space between the walls and with circulation impeding baffles spirally arranged about the inner walls of said space. 18. A method of insulating and cooling a1 refrigerated space, which includes enclosing solid carbon dioxide to absorb heat and discharge refrigerant gas at a high level with respectto said space, and guiding and restraining said eas to maintain a p ool or body of the outflowmg cold gas in heat exchange relation with a5high level portion of said refrigerated space.

19. A method lof insulating and cooling a refrigerated space, which includes enclos-l ing solid carbon dioxide to absorb heat and discharge refrigerant gas at a high level with respect to said space and guiding and restraining downflow of said gas to maintain a pool or body of the. freshly evolved gas in heat exchange relation with a higher level 'portion than said refrigerated space, and

guiding the overflow of gas from said pool-to mamtam a continuous renewed insulatlng layer of the gas interposed between the re-- frigerated space and the exterior.

20. A method of insulating and cooling a refrigerated space, which includes enclosing solid carbon dioxide to absorb heat and discharge refrigerant gas at a high level with respect to said space, guiding and balllng downflow of freshly evolved gas about and in heat exchange relation with the refrigerated spacc, thereby greatly increasing the amount of heat absorbed by the gas in the upper portion of the refrigerated space.

21. A method of insulating and cooling a refrigerated space, which includes enclosing solid carbon dioxide to absorb heat and discharge refrigerant gas at a high level with respect to said space. and guiding and restraining downow of said gas to maintain a pool or body of the freshly evolved gas in heat exchange relation with a higher level portion than said refrigerated space, and guiding the overflow' of gas from said pool to maintain a continuous renewed insulating layer of the gas interposed between the refrigerated s ace and the exterior.

22. AA met od of insulating and cooling a refrigerated space, which includes enclosing solid carbon dioxide in heat exchange relation with said space and guiding and restraining gas evaporated from the solid to maintain a plurality of refrigerant zones of freshly evolved gas encircling said space at differentl levels.

23. A method of insulating and cooling a refrigerated space, which includes enclosing solid carbon dioxide in heat exchange relation with said space, and guiding andrestraining gas 'evaporated from the solid to maintain a plurality of refrigerant z ones of freshly evolved gas encircling said space at tion with said space, and guiding and re-- straining gas evaporatedy from the solid to maintain a plurality of refrigerant zones of freshlyevolved gas encircling said space at different levels, confining the excess gas to maintain a continuously renewed insulating layer of the gas interposed between the refrigerated space and the exterior, and permitting final escape of said excess by high level overflow.

25. The method of refrigerating by solid carbon dioxide, which includes circulating the freshly sublimated carbon dioxide gas through ducts substantially surrounding the refrigerator chamber, retaining part -of the freshly sublimated carbon dioxide gas at a high level in said ducts while permitting overflow of part of it to a lower level and l n 26. A refrigerating apparatus for insulating and cooling a space comprising a chamber for solid carbon dioxide, said chamber being so arranged as lto effect the absorption of heat from anda discharge of refrigerant gasv at a high level with respect to said space, and means for guiding and restraining said gas to effect the maintenance ofa pool or body of overflowing cold gas in a heat exchange relation with a highlevel portion of said space.

Signed at New York, in the county of New York and State of New York, this 20th day of March A. D. 1930. l

CHARLES L. JONES.

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