US2310477A - Refrigeration apparatus - Google Patents

Description

` Feb. 9, 1943. R. H. TULL REFRIGRATION APPARATUS Filed sept. 26, 1940 2 sheets-sheet 1 F/G.- l..

INVENTOR PoBER-r H. Tuu.

WTNE ESZ Mw Feb. 9, 1943. R'. H. 'ru|.|

REFRIGERATION APPARATUS Filed Sept. 26, 1940 2 Sheets-Sheet 2 INVENTOR ROBERT H. TULA.

ATTOR Y lFIG. 5.

Patente Feb. 9, i943 'Armes BEFRIGERATION APPRATUS Pennsylvania Application September 26, 1940, Serial No. 358,433

9 Claims.

This invention relates to refrigeration apparatus and more especially to large refrigerator cabinets.

One object of the invention is to provide a simple construction for large refrigerators, such as display cases.

Another object is to provide a refrigerator of the type described which is cooled to a substantially uniform temperature throughoutV by a single cooling element which does not require a separate drip collector.

A further object is to provide refrigerators of the type described which are adapted for maintaining high humidities in the cabinets.

These and other objects are eiected by the invention as will be apparent from the following description and claims taken in connection with the accompanying drawings, forming a part of this application, in which:

Fig. 1 is a sectional view in perspective of the refrigerator of this invention, taken on the line I-I of Fig. 2;

Fig. 2 is a partial section taken on the line of the front wall I2 of the cabinet and is slanted rearwardly to provide a view of the contents of the cabinet. The upper portion of the rear wall i3 is sloped similarly and provided with tripleglazed doors It, which slide past one another to afford access to the interior of the upper portionof the cabinet. The lower portion of the rear wall I3 is provided with two doors I5 which provide access to the lower portion of the cabinet.V

The cabinet is divided into an upper food storage chamber I6 and a lower food storage chamber I'I by a sloping grid I8 resting on supports I9 secured to the front wall I2 and the rear wall I3. A flat cooling unit 2| is located in the lower food chamber I'I adjacent-but spaced from the front wall I2 of the cabinet I0 and extends from the bottom of the chamber I'I to nearly the top thereof and from one end of the chamber I1 to nearly the opposite end thereof. The cooling unit 2| comprises a series of parallel and spacedapart metal strips 23 standing on end and a refrigerant-carrying tube 2l passed back and forth through registering holes' in the strips 23. The tube 24 may be supplied with refrigerant from a source such asa compressor-condenser unit (not shown in the drawings). A horizontal baille 22 is secured to the upper edge of the cooling unit and extends to wall I2, adjacent thereto to form a confined air passage 25 together with the cooling unit 2|, the wall I2, and a portion of the bot` tom wall 30 of the lower food chamber Il.

An air duct 26 is located adjacent the upper wall on the interior of the cabinet and occupies the entire area of this wall. The air duct 26 is provided with openings 21 on its lower surface which communicate with the upper chamber I6.

A false end wall 28 is located adjacent the end wall 29 of the cabinet ||l to provide an air duct 3| with said end wall 29 which air duct 3| communicates with the upper air duct 26. A circular opening 32 is provided near the bottom of the false end wall 28 and adjacent the cooling unit 2 I, and a baille 33 is located diagonally across the corner of the lower food storage chamber Il which together with an extension 2D of the horizontal baille 22, provides communication between the circular opening 32 and the air passage 25 adjacent the cooling unit 2|. A housing 34 carrying a motor 36 is secured in the circular opening 32 and a fan 3l is secured to the shaft of the motor 36. The fan 3l is adapted to draw air through the air ducts 3| and 26 from the 'upper portion of the upper food storage chamber i6 and pass it to the air passage 25 adjacent the cooling unit 2|, the air thereafter passing through the cooling unit 2 -The particular arrangement of the strips of metal 23 of the cooling unit 2| and the direction of air flow in the passage 25 is such as to force the air circulated by the fan 3l through the cooling unit 2| in a path which does not permit portions of the air to remain in prolonged contact with any of the cooling surfaces of the cooling unit 2|. Prolonged contact of portionsof the air with the cooling surfaces of the cooling unit would chill these portions of the air excessively thereby causing the moisture in these portions of air to condense and deposit on the cooling unit 2|. Such action is not desired in a refrigerated cabinet of this nature because it is essential that all moisture is retained in the air as far as possible to preserve the humidity of the air. To

`minimize the length of time that the air is in contact with the cooling unit 2|, the latter is relatively thin, a thickness of about one and onehalf inches for a cooling unit about five feet in length having been found suitable. The openings 21 in the upper air duct 26 are proportioned toprovide a substantially uniform air iiqw through the cabinet I0 and for this reason are more numerous at the portions of the duct 26 farthest removed from the fan 3l.

The cooling unit 2| keeps the display case at a substantially uniform temperature. The chilled air from the central and lower portion of the cooling unit 2| sweeps through the lower food storage chamber I1,- absorbs heat therefrom and passes upwardly through the upper food storage chamber I6. The air from the upper portion of the cooling unit 2| flows more directly to the upper food storage chamber I5 without absorbing much heat from the lower food storage chamber I1 and is thus available for absorbing heat from the upper food storage chamber I6.

To aid the passage of the air through .the cooling unit as above described, a cellular louver 35 comprising crossed louver boards 40 is provided at the entrance of the air passage 25. The louver 35 dampens tlie eddy currents-ordinarily found in air flowing in irregular air ducts and the air swirls caused by the fan 31 so that the air passing through the cooling unit passes therethrough in` quiescent layers. l

The cooling unit 2| is -maintained at a temperature suiiiciently high to prevent the accumulation of frost thereon and is of large area in order to cool large quantities of the aixl passing through it substantially uniformly bya few degrees of temperature rather than by cooling a smaller quantity of air through a larger temperature range. This again avoids cooling porytions of the air in the cabinet to a temperature low enough Ato cause precipitation of substantial quantities of the water vapor in the air.

The rate of air flow through the two food storage chambers |6 and from the-cooling unit 2| to the upper air duct 26 is about 15 feet per minute and is maintained at this low value to avoid the rapid sweeping of air over the foods displayed in the cabinet as this would tend to dehydrate the food. The current of air is furthermore directed upwardly through the food storage chambers so that the .trays and platters on which moist foods are ordinarily displayed act as a, wind break for the foods. It has been found that in actual practice a humidity of 85 per cent can be maintained in the cabinet.

The lower portion of the lower 'food storage chamber is of leak-proof construction and the openings for the doors I5 are elevated above the bottom of the chamber I1 to prevent escape of the moisture condensed by the cooling unit 23. A drain 38 is also provided in the bottom of the lower food storage chamber I1 to carry ofi the moisture collected thereon. `This construction makes the use of a drip collector unnecessary.

A platform for supporting the articles to be refrigerated is located in the lower food storage chamber, which platform comprises girders 4| resting on the bottom 39 of the lower food stor-l age chamber and cross pieces 42 placed across the girders 4|.

It will be observed that this invention provides a large refrigerator of the display case type, which refrigerator is of simple construction and maintains a substantially uniform temperature and high humidity for the preservation of foods.

While I have shown my invention in but one 1. In a refrigerator, the combination of an insulated cabinet, the length of which exceeds its breadth; a foraminated partition in said cabinet dividing the same into an upper and aflower food storage chamber; a nat cooling unit adjacent but spaced from one of the longitudinal walls of the lower food 'storage chamber, said cooling unit being substantially commensurate with said wall, said cooling .unit having air passages therein substantially at right angles to the flat portion thereof; a substantially horizontal balle at the upper edge'of the cooling unit extending to the wall adjacent thereto to define an air duct t0- gether with said wall, said cooling unit, and av storage compartment to cool said compartments' substantially uniformly.

2. In a refrigerator, the combination of an insulated cabinet, the length of which exceeds its breadth; a foraminated partition in said cabinet dividing the same into an upper and a lower food storage chamber; a flat cooling unit adjacent but spaced from one of the longitudinal walls of the lower food storage chamber, said cooling unit being substantially commensurate with said wall, said cooling unit having air passages therein substantially at right angles to the flat portion thereof; a substantially horizontal baille at the upper edge of the cooling unit extending to the wall adjacent thereto to define an air duct t0- gether with said wall, said cooling unit and a portion of thebottom of said cabinet; a louver comprising a series of parallel baille plates in said air duct to suppress eddies of air in said duct; a second duct adjacent the upper interior wall of said cabinet and extending substantially the full length thereof, said duct having a plurality of openings distributed throughout its length and communicating with the upper food storage chamber; and means for forcibly conducting air from said second duct to said flrst-named duct, the air thereafter passing substantially horizontally through the air passages of the cooling unit, the air thereafter flowing upwardly from the lower to the upper food storage compartment.

3. In a refrigerator, the combination of an insulated cabinet, the length of which exceeds its breadth, said cabinet defining a foodA storage chamber, a fiat cooling unit adjacent to but spaced from one of the longitudinal walls of the cabinet and extending along substantially the full length of said wall, said cooling unit having its lower edge adjacent'the bottom of said cabinet and its upper edge extending upwardly in said food storage chamber to at least one-third the height thereof, said cooling unit having air passages therein at right angles to the flat portion thereof, a substantially horizontal baille at the upper edge of the cooling unit extending to the wall of the cabinet adjacent thereto, a duct adjacent the upper interior wall of said cabinet and extending substantially along the full length thereof, said duct having a plurality of openings distributed throughoutits length and communieating with the' food storage chamber, a second duct communicating with said rst-named duct and vwith the space between the cooling unit and the wall adjacent thereto, means for forcibly circulating air through said second duct in. a direc tion toward said space whereby said air passes through the air passages of the cooling unit substantially at right angles to the flat side thereof and flows through said food storage chamber to maintain the temperature of the top and bottom portions thereof substantially uniform.

4. In a refrigerator, the combination of an insulated cabinet, the length of which exceeds its breadth, a foraminated partition in said cabinet dividing the same into an upper and a lower food storage chamber, a flat cooling unit adjacent but spaced from one of the longitudinal walls of the lower food storage chamber, said cooling unit comprising a series of spaced-apart thin metal strips with the flat sides facing one another, said strips extending substantially from the bottom to adjacent the top of the lower food storage chamber, and the series of spaced-apart strips extending along at least three-quarters of the length of said lower food storage compartment, a substantially horizontal baffle at the upper edges of said spaced-apart strips and extending to the vertical wall adjacent the cooling unit, a duct adjacent the upper interior wall of said cabinet and extending substantially along the full length thereof, said duct having a plurality of openings distributed throughout its length and communicating with the food storage chamber, a second duct communicating with said first-named duct and with the space between the cooling unit and the wall adjacent thereto at one end of said space, and means for forcibly circulating air from said duct at the upper portionv of the cabinet through said second duct, the air thereafter passing through at least a portion of the space between the cooling unit and the wall adjacent thereto and thereafter between the thin strips of metal, the thin strips of metal guiding fsaid air at right angles to its direction of travel through said space through the cooling unit and into the lower food storage chamber, the air thereafter passing upwardly through the foraminated partition into the upper food storage chamber towards the openings in the duct adjacent the upper wall of said upper food storage chamber.

5. In a display case, the combination of an insulated cabinet, the length of which exceeds its. breadth; a foraminated partition in said cabinet to divide the same into an upper and a lower food passages of the cooling storage chamber; an inclined window in the upper food storage chamber; an access opening and a door for the same in the lower food storage chamber, said access opening being elevated above the bottom of said cabinet; aflat cooling unit adjacent but spaced from one of the longitudinal walls of the cabinet and extending along substantially the full length and height of said wall, said cooling unit having air passages therein substantially at right angles to the flat surface thereof; a substantially horizontal baille at the upper edge of the cooling unit and extending to the Wall adjacent thereto to define an air 'duct together with said wall, cooling unit, and a portion of the base of the cabinet; a second duct adjacent the upper interior wall of said cabinet and extending substantially thereof, said duct having-a plurality of openings distributed through its length and communicating with the upper food storage chamber; a third duct communicating with the duct in the upper portion of the cabinet and the air duct adjacent the cooling unit; means for forcibly'circulating along the full length` air through said second duct towards said firstnamed duct behind the cooling unit; and a drain in the bottom wall of the cabinet, the lower portion of said cabinet being of leak-proof construc-` between said vertical wall and said cooling unit,

said cooling unit having 'horizontal air passages therethrough, and means for moving air from the upper portion of the food storage chamber to said air passage, said air, thereafter, flowing substantially horizontally through the air passages of the cooling unit and into the food storage chamber.

'7. In a refrigerator, the combination of an insulated cabinet, said `cabinet defining a food storage chamber, a fiat cooling unit at the lower portion of the cabinet and positioned substantially parallel to, but spaced from one of the vertical walls of the cabinet to define an air' duct between said vertical wall and said cooling unit, said cooling unit having horizontal air passages therethrough, and means for moving air from the upper portion of the food storage chamber to said portion of the cabinet and positioned substantially parallel to, but spaced from one of the vertical walls of the cabinet to define an air duct between said vertical wall and said cooling unit, said cooling unit beingof a height of at least 1A the interior height of the cabinet and having horizontal air passages therethrough, and means for moving air from l'the upper portion of the food storage chamber to said air passage, said air, thereafter, flowing substantially horizontally through the air unit and into the food cooling unit being subfor cooling said food storage chamber, said stantially the sole means storage chamber. l

9. In a refrigerator, the combination of an in*- sulated cabinet having at least one substantially` vertical wall and an upper wall, said cabinet defining a food-storage chamber, a cooling unit in said cabinet adjacent to said substantially vertical wall of the cabinet and extending substan- `tially the full length of said wall, saidicooling unit having its lower edge adjacent the bottom of said cabinet and extending upwardly in said food-storage chamber to at least one-third the height thereof, said cooling unit having air passages therein at right angles to said substantial- 1y vertical wall, a duct in said cabinet adjacent said upper wall and extending substantially the full length thereof, said duct having a plurality of openings distributed throughout its length and

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