US2626508A

US2626508A - Open-top refrigerated display case

Info

Publication number: US2626508A
Application number: US70555A
Authority: US
Inventors: George K Bently
Original assignee: MCCRAY REFRIGERATOR Co IN
Current assignee: MCCRAY REFRIGERATOR Co IN; MCCRAY REFRIGERATOR COMPANY Inc
Priority date: 1949-01-12
Filing date: 1949-01-12
Publication date: 1953-01-27
Anticipated expiration: 1970-01-27

Description

Jan. 27, 3953 K. EN 2,626,508

OPEN-TOP REFRIGERATED DISPLAY CASE Filed Jan. 12, 1949 3 Sheets-Sheet 1 oPEN Georg K. Eenf/y, BY 2 v a) 2 ATTORNEY-9 Jan. 27, 1953 G. K. BENTLY OPEN-TOP REFRIGERATED DISPLAY CASE 3 Sheets-Sheet 2 Filed Jan. 12, 1949 QQZQ. 22:: 42 @QQQ INVENTOR. George A. fienf/y, @uwvZW A TORNEYS Jan. 27, 11953 e. K. BENTLY OPEN-TOP REFRIGERATED DISPLAY CASE 3 Sheets-Sheet 3 Filed Jan. 12, 1949 /I ll I/ l l/ 1/ x I AW BH U JNVENTOR. George K Ber/fly, WZM

ATTORNEY! ?atented Jan. 27, 1953 OPEN-TOP REFRIGERATED DISPLAY CASE George K. Bently, Kendallville, Ind., assignor to McCray Refrigerator Company, Inc., Kendallville, Ind., a corporation of Indiana Application January 12, 1949, Serial No. 70,555

7 Claims.

This invention relates to open-top refrigerated display cases of the type used in food stores to display merchandise of a perishable nature.

The primary object of the invention is to improve on refrigerated display cases of this character by effecting a more efficient and uniform cooling of produce with a less loss of cooled air to the outside atmosphere than with the cases now generally used, and to accomplish this in asimple and economical manner.

Other objects and advantages of the invention will be apparent from the following detailed description, and from the accompanying drawing illustrating a preferred embodiment thereof, in which- Fig. l is a front perspective view of a case embodying the invention; Fig. 2 is an enlarged section thereof on the line 2--2 in Fig. l, and Figs. 3 and 4 are reduced sections taken on the lines 3-3 and 4-4, respectively, in Fig. 2.

Referring to the drawings, I designates the

front wall

2, 2 the opposing end walls, 3 the rear wall and 4 the bottom of the case body. The rear wall 3 extends above the level of the front wall, and is provided at its upper end with a forwardly extending top 5 that is narrow in its forward extension so as to provide a top access opening to the interior of the case of considerable area between said top and the front wall of the case. The front edge of the top 5- is provided with a downwardly extending baffle 6 that is preferably but necessarily forwardly inclined. A metal facing sheet I for the top extends forwardly a distance from the front edge of the top and then downwardly a short distance on a forward incline to form a front canopy 8 the full length of the top. A source 9 for directing a, light into the case is disposed under the canopy 8 and preferably extends substantially the length of the case. The exposed front side of this canopy forms a price tag rail.

The front body wall I is considerably lower than both the rear wall 3 and the

end walls

2,2, and is extended to near the level of the front end edges of the end walls by a front wall part In preferably of glass, so that the produce in the case may be viewed therethrough. The top edges of the end walls extend rearwardly on a slight incline to the lower front edge of the canopy 8. The baflle 6 extends down a distance into the case with its lower edge below the level of the high rear end portion of the

ends

2,2, and preferably above the level of the top edge of the front wall part Ill. In the present instance, the bottom edge of said baflie is approximately half way between the top edge level of the part II] and the bottom edge level of the canopy front.

The interior of the case is provided in its upper portion with an open-top produce display chamber [2, the bottom of which is indicated at l3 and may comprise sheet metal sections that are removable to permit access to parts below and which rest at their rear end edges on a rear ledge M and at their front end edges on a front ledge i5. The ledges l4 and I5 are formed at the upper edges of rear and front vertical partitions it and I1, respectively, which extend the full length of the interior of the case with both partitions spaced from the respective rear and front case walls.

The rear wall of the display chamber I2 is formed by a vertical partition l8 extending upward from the rear edge of the ledge M to near the top 5 at the rear of the baffle 6 throughout the length of the case and in forwardly spaced relation to the rear wall 3 to form a vertical flue Ill therebetween. This flue is divided lengthwise into a plurality of sections by vertical webs 2i? serving as braces for the partition l8. These webs are provided with openings Zl for the free passage of air therethrough.

The flue 19 at its lower end communicates with and is supplied with cool air from a distributing chamber 22. The upper end of the flue I9 is preferably somewhat restricted by reason of the upper end portion of the partition [8 being slightly rearwardly inclined at such point so that the discharge of air from the flue is upward under the top 5 and thence forward and downward under the banle 6 into the top rear portion of the display chamber I2. The air in its discharge from the flue into the interior of the case is diffused and retarded to some extent by a screen or foramlnous partition 23 which extends rearwardly and downwardly from the baffle is a distance above its lower edge portion of the partition l8. Upwardly beyond this point, the partition i8 is preferably formed with a perforated or slotted extension lta which tends to further diffuse and retard the air in its discharge from the flue 19 into the case.

A partition 24 extends upward from the forward edge of the ledge [5 for the entire length om case and in rearwardly spaced relation to the front wall to form the flue 25 in the front portion of the case. The partition 24, in the present instance, extends vertically to near the lower edge of the front wall part l0 and then continues upward at a forward incline, as shown at '26, to a short distance below the top of the wall part l and in rearwardly spaced relation thereto to provide a narrow slot-like entrance 2! to the upper end of the flue 25. The

parts

24 and 26 of this partition, in the present instance, are shown as connected by an offset 28, and the part 26 is preferably of transparent glass to permit articles in the case to be viewed therethrough. A plurality of bracket plates 29 are attached to the inner side of the front wall I and serve as supports and braces for the

partitions

24 and 26.

The produce is supported in the case by a shelf 30 extending the entire length of the display compartment I2 and slatted or perforated to permit the circulation of air therethrough. The shelf 30 is preferably composed of a plurality of rectangular tray-like members placed side by side to permit any or all to be removed or vertically adjusted. These trays are adapted to be placed in various positions best suited to the display of the particular mechandise in hand and also for the selective distribution of cold air above and below the shelf, as hereinafter described. For this purpose, the trays may be placed in different vertically spaced horizontal positions a, b, or inclined upwardly and rearwardly from either of such positions, as shown at c, d, e and J in Fig. 2, or the trays may rest on and be supported by either the bottom l3 or the ledges l4 and [5. In the a position, a tray is supported at its rear end by a ledge 32 on the front of the rear flue wall 18, and at its front end by releasable hooked engagement with the front partition 24, as shown at 33. The trays may be tilted from this position to any of the positions c, d and e by raising their rear ends to be supported, respectively, by

ledge brackets

34, 35 and 36 provided in superimposed relation on the front side of the partition [8. When the trays are in the raised horizontal position b they are supported at their rear ends by the ledge 34 and at their front ends by the hooked connection 3'! with the partition 24. The trays may be tilted from this position to the position I by resting their rear ends on the ledge brackets 36. If desired, the trays 30 may be removed and the produce supported by the bottom trays I3.

The partition [8 is provided lengthwise thereof between the

ledges

32 and 35 with a plurality of louvered openings 4l2- and also with similar openings 4| and 42 between the

ledges

34 and 35 and the

ledges

35 and 36, respectively. These openings direct air from the flue l9 forwardly and downwardly into the compartment l2 below the shelf trays 30 when in any of their several positions, except, in the present instance, the bottom position a. These openings, or some of them, also serve to direct air into the compartment above the trays when in the various positions other than c and f.

The front partition 24, in the present instance below the tray position a, is provided with a series of comparatively small openings 44 for the exit of air from the compartment [2 to the interior of the down flue 25. These openings combined with the inlet openings 21 for the flue 25 are of sufficient combined area to take care of the low pressure cold air admitted to the compartment [2 through the various openings from the flue IS.

The flue 25 opens at its lower end into a plenum chamber 45 formed at its rear side by the partition I1, and this partition has an opening 4%; in its central portion through which a motor driven fan 4! drives the air rearwardly through a broad flue 48 having a restricted portion 49 at its rear end in which a cooling coil 50 is disposed to cause the air passing therethrough to be cooled the desired extent. The rear end of the flue part 49 'wall 3 and partition l5.

opens into the air distributing chamber 22 in the lower portion of the flue l9. While the flue part 49 is restricted in width relative to the length of the case, it is still of considerable width, as shown in Fig. 3. The chamber 22 into which the flue 49 discharges is formed at its top and sides by a semicircular perforated or foramlnous baffle 51, which causes the air discharged into the chamber 22 to be trapped and pressurized and evenly distributed into the central and end portions of the flue 19. The bafile 5i is disposed between the rear TlllS is found to be an important feature for the completely satisfactory operation of a case constructed as shown.

In the operation of the case, air is drawn from the display compartment l2 through the inlet openings 2'! and 43 to the flue 25 and thence to the chamber 45 by the action of the fan 41, and is forced by the fan through the cooling coil fiue 49 and into the distributing chamber 22 where it is pressurized and its flow restricted by the perforated arcuate baffle 5|. This baflle causes the air to be distributed uniformly, vertically and sidewise into the bottom of the up flue [9 so that the air flow throughout the entire horizontal length of the flue is substantially equalized. Some of this air in its passage up the hue is distributed to the chamber l2 through the louvered openings 40, 41 and 42, with more or less of it passing under the merchandise supporting shelf 30, depending on the adjusted position of the shelf trays or sections except when resting on the bottom l3 or when in the lower horizontal position a. The louvers, which are above the shelf in any position of its adjustment, are designed to direct the discharging air down onto the shelf and onto the produce supported thereby, while those that are below the shelf, which is in all positions except a, cause a supply of cold air to flow beneath the shelf, a portion of which discharges to the flue 25 through the openings 43 with the balance passing up through the slatted or perforated shelf and around the produce thereon. This manner of circulation causes distribution of cold air directly to the bottom of the produce so that its lower portion is maintained at a substantially uniform temperature with its upper portion that is cooled by the discharge of cold air into the upper portion of the chamber. This is an important feature, for in systems where the cold air passes either up or down, but not both, through the shelf and supported merchandise, the air is warmed in its contact with the merchandise, so that the far side of the merchandise with respect to the air flow is necessarily warmer than the near side. This is especially true with respect to large produce rticles or packages, such for instance as meat, and may result in such a temperature differential in the package that portions may not be maintained at a safe temperature to prevent spoilage or objectionable bacteria formation. The extent of cold air caused to be discharged below the shelf and to pass upward therethrough depends, of course, upon the adjusted position of the shelf and the number and extent of louver openings 4! and 42 that have their discharge below the shelf. The cold air that is discharged above the shelf through the louvered openings from the up or cold flue I9 is directed downwardly against the produce on the shelf and flows slightly thereover to its point of discharge from the chamber through the outlet flue opening 21. At the same time the stream of cold air discharging from the top of the flue 19 under the battle -6, and the air rising through the shelf 30, commingle with the air discharging from the louvered openings and passes therethrough into and down the discharge flue 25. The air discharging from the flue i9 is at a relatively lower pressure than that passing through the return flue 25.

The air discharging into the chamber l2 from the upper end of the flue l9 forms a blanket of cold air over the air discharging from the louvered openings and compensates to a large extent for the heat taken up from the produce by such louver discharging air. This also protects the produce contacting air from the warmer outside air.

In practice, it is preferable to have the air discharge into the chamber i2 from the upper end of the flue l9 above the level of the top edge.

of the front wall part II]. It is also preferable to pull only a limited quantity of air from the lower portion of the chamber l2 through the small openings 33 sufficient only to maintain a slow circulation through the area beneath the shelf with a considerable portion passing up through the shelf. The amount of refrigeration underneath the shelf is determined by the position of the shelf, and consequently the number of effective openings 40, 4| and 42 available for the purpose. Thus, a raising of the shelf position increases such refrigeration and a lowering decreases it. It is found in practice that no particular advantage would be derived by controlling the discharge through the openings 33 by use of a valve and for this reason no valve has been shown. However, such a controlled discharge may be employed if desired. It is further found in practice that with the circulation as illustrated the air is forced out of the top of the flue [9 at the back of the chamber 12 at low velocity, nd is taken in the narrow flue opening 2? near the top edge of the wall part it at high velocity, and that this minimizes the amount of cold air spilled to the atmosphere and also the amount of warm air taken in from the outside.

I wish it understood that my invention is not limited to any specific construction, arrangement or form of the parts, as it is capable of numerous modifications and changes without departing from the spirit of the claims.

Having thus described my invention, what I claim as new, and desire to secure by United States Letters Patent, is:

l. In an open-top refrigerated display case, a produce display chamber, a broad flue for directing cold air to said chamber, means for forcing cold air through said flue, and an arcuate perforated baiiie in the inlet end of the flue serving to pressurize and distribute the air in various directions into the flue to render the air flow substantially uniform throughout the broad area of the flue.

2. In an open-top refrigerated display case, a produce display chamber, a broad vertical flue for directing cold air to said chamber, an arcuate perforated baffle forming an air distributing chamber in the lower end of said flue, said distributing chamber being of less width than said flue and said bailie having its bowed side upward whereby air is distributed upward and sideways therethrough to the flue, and means for cooling and forcefully discharging air into said distributing chamber.

3. In an open-top refrigerated display case having front, rear and end walls, means within the case forming an open-top produce display chamber and vertical flues at the front and rear 6, sides thereof, the flues being narrow from front to rear and substantially corresponding in width to the horizontal length of the chamber, the rear flue having a plurality of vertically spaced rows of louvered openings directing air downwardly therefrom into said chamber, and said front flue having its top open to the chamber below the top of the front wall and having a lower series .of openings for the inlet of air from the chamber, a produce supporting shelf having provision for the passage of air therethrough, means for supporting the front edges of the shelf above said lower series of openings to the front flue, and a plurality of vertically spaced supports at the front of said rear flue to selectively support the rear edge of the shelf in different vertically spaced positions to place a greater or less number of said rear louvered openings below the shelf, and means below said chamber communicating with the lower ends of said flues and operable to create an up draft through said rear flue and a down draft through said front flue.

4. In an open-top refrigerated display case having front, rear and end walls, means within the case forming an open-top produce display chamber and vertical flues at thefront and rear sides thereof, the flues being narrow from front to rear and substantially corresponding in width ,to the horizontal length of the chamber, the rear flue having a plurality of vertically spaced rows of louvered openings directing air downwardly therefrom into said chamber and said front flue having its top open to the chamber below the top of the front wall and having a lower series of openings for the inlet of air from the chamber, a produce supporting shelf having provision for the passage of air therethrough, means for supporting the front edges of the shelf above said lower series of openings to the front flue and a plurality of vertically spaced supports at the front of said rear flue to selectively support the rear edge of the shelf in different vertically spaced positions to place a greater or less number of said rear louvered openings below the shelf, means communicating with the lower ends of said flues and operable to create an up draft through said rear flue and a down draft through said front flue, and an arcuate perforated bafile in the inlet end of the rear flue to pressurize and distribute the air in various directions into the flue to render the air flow substantially uniform throughout the broad area of the flue, said bafile disposed widthwise of the lower end portion of the rear flue and having its convex side upward and its concave side disposed toward and receiving the air from the said draft creating means.

5. In an open-top refrigerated display case having front, rear and end walls, means within the case forming a produce display chamber, a second chamber therebelow and vertically disposed flues connecting said chambers at the inner sides of two opposing walls of the display chamber, one flue being for cold air and the other for relatively warm air, a shelf in said display chamber spaced from its bottom and having openings for the passage of air therethrough, said cold air flue having provision for discharging air therefrom into the display chamber at at least one side of said shelf, and said other flue having provision both below and above the shelf for the inlet of air thereto from the display chamber, and means in said second chamber for drawing air from said warm air flue and cooling and forcing it through said cold air flue.

6. In an open-top refrigerated display case having front, rear and end walls, means within thecase forming an upper produce display chamberancl a lower chamber and vertically disposed lines at the innersides of two opposing walls of the'upper chamber, oneflue being for cold air and located at the rear of the upper chamber and the other fiue beingior :relatively warmair, said cold air flue having openings for discharging air into the rear. of said upper chamber, aproduce supporting. shelf in said upper chamber vertically spaced relation to its :bottom and being vertically adjustable relative to the discharge openingsin-said cold air .fiueto vary the amount of .cold air discharging into the chamber below the shelf, .saidlshelf having provision for the passage of air "therethrough'from the upper to the lower portion of .its chamber and said warm air flue having provision for the inlet of air thereto from the upperportion .of said upper chamber abovezthe shelf and alsofrom the lower 8 portion thereof below the shelf, and means in the lower chamber for drawing air from said warm .air flue and cooling and forcing it through said cold air flue.

7. A combination as called for in claim 6 wherein the openings from the cold air flue are at different levels and some at least thereof are louvered'to direct the discharging air downwardly into the upper chamber.

GEORGE K. BENTLY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED vSTATES PATENTS Number Name Date 2,223,761 Hall Dec. 3, 1940 2,447,759 MacMaster Aug. 24, 1948 20 2,463,614 Hardin Mar. 8, 1949 2,508,255 Hardin May 16, 1950