US3125864A

US3125864A - Self-service refrigerated display case

Info

Publication number: US3125864A
Authority: US
Publication date: 1964-03-24
Anticipated expiration: 1981-03-24

Description

March 24, 1964 w. E. URAL 3,125,864

SELF-SERVICE REFRIGERATED DISPLAY CASE Filed Oct. 16, 1962 6 2 Sheets-Sheet 1 'O INVENTOR W/L /AM E. URAL m q E March'24, 1964 w. E. URAI. 3,125,864

SELF-SERVICE REFRIGERATED DISPLAY CASE Filed 001'.. 16, 1962 2 Sheets-Sheet 2 i: 2 f// ff tzi'. /'/;y Figa' BY @wf/v7 CaSeS.

United States Patent O,F

3,125,864 SELF-SERVICE REFRIGERATED DISPLAY CASE William E. Ural, Yardley, Pa., assigner, by mesne assignments, to The American Hardware Corporation, a corporation lof Connecticut Filed Get. 16, 1962, Ser. No. 230,352 Claims. (Cl. 62--256) This invention relates to refrigerated display cases and is directed particularly to display cases which are open at the front for access to the display space and are arranged so that refrigerated air will ow downwardly adjacent the access opening or in front of shelves within the display space.

It has been common practice heretofore to provide refrigerated display cases with a relatively high back wall which may be provided with one or more vertically spaced shelves and to provide the front of the case with an access opening through which the shelves and display space are accessible. Such display cases are ordinarily provided with means for circulating refrigerated air downwardly adjacent the access opening in the front of the case to a return air duct opening adjacent the lower edge of the access opening.

The air thus circulated is sometimes presented in the form of a downwardly flowing air curtain or barrier which extends from a cold air outlet adjacent the upper edge of the access opening to an air return duct having a return air inlet adjacent the lower edge of the access opening. In other constructions cold air may flow forward from the back Wall of the case or downward from the top of the case onto the shelves and thereafter cascade downward over the front edges of the shelves so as to flow downward adjacent the access opening in the front of the case. The air then is returned to be recooled and recirculated by passage to a return air duct having a return air inlet adjacent the lower edge of the front access opening.

When employing either type of air circulation, the downwardly flowing refrigerated air entrains or induces a downward flow of ambient air adjacent the front access opening. The air thus caused to flow downward is cooled by the transfer of a portion of its heat to the refrigerated air and by commingling therewith. As a result, the volume of air which flows downward toward the return air inlet is increased and generally exceeds the capacity of the inlet and return air duct. Therefore, substantial volumes of cool or relatively cold air spill forward out of the case causing substantial loss in refrigeration and creating an uncomfortably cold condition for the feet and legs of customers in the aisle in front of the case.

In accordance with the present invention, the uncomfortable conditions thus created are reduced or eliminated and a substantial saving in heat loss and an increase in the efficiency of operation of refrigerated display cases may be attained.

These advantages are preferably attained by providing open front display cases with one or more added or 'enlarged ducts or passages through which substantially all or the major portion of the cooled air owing downward toward the lower edge of the access opening may be passed. A portion of such cooled air may then be refrigerated again and returned to the display space in a continually recirculating cycle as in conventional front access display However, the other portion or remainder of the cooled air may be directed elsewhere to aid in air conditioning the store, to refrigerate other equipment, to cool a condenser, or it may be utilized in any other manner desired or simply discharged to some space where it will not be objectionable.

Accordingly, the principal objects of the present inven 3,125,864 Patented Mar. 24, 1964 ICC tion are to prevent objectionable spilling over of cooled air adjacent the lower edge of an access opening in the front of a refrigerated display case, to assure more elfective utilization of refrigeration in front opening display cases, and to control the flow of ambient air which is cooled by refrigerated air flowing downward adjacent the front access opening in a refrigerated display case.

These and other objects and features of the present invention will appear from the following description thereof wherein reference is made to the gures of the accompanying drawings.

In the drawings:

FIG. 1 is a vertical sectional View through a typical form of refrigerated display case embodying the present invention;

F IG. 2 is a horizontal sectional view through the display case shown in FIG. 1;

FIGS. 3, 4 and 5 are sectional views illustrating various alternative embodiments of the present invention.

In that form of the invention chosen for purposes of illustration in FIGS. 1 and 2, the display case has a base or insulated bottom, a vertical rear wall 4 and a top or hood 6. The ends 8 of the case slope forward from the ends of the hood 6 to lower front wall 10 which denes the lower edge of an access opening 12 in the front of the case. Shelves 14 are arranged in vertically spaced relation Within the display space 16 and in position to be accessible through the front opening 12 of the case.

The bottom of the display space 16 is defined by a lower floor or pan 18 which is spaced from the base 2 of the case so as to provide a refrigerating space 20 within which is located the evaporator 22 of a refrigerating unit. A second evaporator unit 24 is located at the rear of the display space and extends vertically adjacent the rear insulated wall 4. A blower 26 is positioned between the

evaporators

22 and 24 and serves to cause air to be circulated beneath the oor 18 of the display space and over the

evaporators

22 and 24 so as to be forced upward through the refrigerated air duct 23 to the air discharge spaces 30 beneath the shelves 14 and the air discharge space 32 beneath the hood 6.

The refrigerated air is thus caused to flow forward and downward over the articles in the display space 16 and located on the shelves 14. The air then ows forward to duct means 34 located at the rear of the lower front wall 10 of the display case and below the front access opening 12. In so doing, the refrigerated air protects the articles on display from the ambient air in front of the case and forms an air curtain or barrier 36 of refrigerated air moving downward adjacent the access opening 12. This movement of the air. establishing the air barrier 36 serves to Ycause the ambient air adjacent and in front of the access opening 12 to give up heat by conduction to the air of the barrier 36 and also causes some of said air to be entrained and mingle with the air of the barrier 36. In this way, an induced stream of the ambient air 38 is created adjacent the access opening 12 substantially increasing the volume of the air owing downward toward the duct means 34 adjacent the lower edge of the access opening 12.

In a typical embodiment of the invention as shown in FIG. 1, the display case may be used for the refrigeration and display of frozen foods. In such a case, the refrigerated air issuing from the

spaces

30 and 32 to the display space 16 may be at a temperature of about 10 F.; whereas, the ambient air may be 70 F. The temperature of the air in the barrier 36 will then increase as it ows downward by reason of the absorption of the ambient air will be lowered until they reach the lower edge of the access opening at temperatures of, say +l F. and +40 F. respectively. However, the volume of these combined streams of air will be nearly twice the volume of the refrigerated air which was discharged into the display space from the

spaces

30 and 32 beneath the shelves. As a result, there would be a tendency for the induced stream of air 3S at a temperature of only about 40 F. to spill out over the lower front wall 10 of the display case at the lower edge of the access opening 12. It is the spilling of this cold induced air which has heretofore been found objectionable because of the loss of refrigeration and the chilling of children and the feet of adults or the legs of customers wearing shorts or having no stockings.

In accordance with the present invention, the duct means 34 adjacent the lower front wall of the display case has a greater capacity or cross section than the duct 28 at the rear of the case through which the refrigerated air from the

evaporators

22 and 24 are passed to the discharge spaces 3,0 and 32 beneath the shelves 14. As a result, all or the major portion of the air in both of the

air streams

36 and 38 is drawn into the duct means 34 and little, if any, of the chilled air spills over the lower front wall of the case.

As shown in FIG. l, the duct means 34 is preferably divided into two separate ducts or passages into which the parallel flowing air streams 36 and 3S may be directed. Thus, the duct means 34 may embody a refrigerated air return passage 4) having an inlet opening 42 through which the colder air stream 36 may be returned to the evaporator 2.2 and blower 26. In a similar way, the duct means 34 may embody a chilled air passage 44 having an inlet opening 46 through which air may ilow to a blower 48. From the blower 48 the chilled air, which may be at a temperature of about 40 F., may be passed to a discharge flue 50 or to any other suitable location where the chilled air may be utilized or will not be objectionable.

As shown in FIG. 1, the inlet opening 42 of the refrigerated air return passage is located below and inward from the inlet opening 46 of the chilled air passage 44. This arrangement of the air inlet openings of the passages of the duct means 34 is preferred since the two streams of

air

36 and 38 are generally parallel to each other and essentially laminar in character. However, the air inlet openings may be otherwise arranged and the division of the duct means 34 into two separate passages need not be effected until the laminar streams of air approach the lower portion of the duct means 34 adjacent the lower front wall 10 of the case.

Further, as shown in FIG. 1, the discharge flue 50, through which the chilled air is forced by the blower 48, may extend upwardly adjacent the rear wall 4 of the display case to an outlet opening 52 adjacent the hood 6 or the top of the display case. The chilled air is, thus, discharged upwardly toward the ceiling or upper portions of the store or area where the display case is located so that it will mingle with the warm air in the store and reduce the temperature thereof. In this way, the chilled ambient air, which would otherwise be spilled out of the case in an objectionable manner, could be used to reduce the load imposed on air conditioning equipment employed for cooling the air in the store or elsewhere.

In the alternative and as shown in FIG. 3, the chilled ambient air from passage 60 of the duct means may be directed to another display case or area to be chilled. Thus, the passage 60, through which the chilled air from duct means 34 is passed, may be directed to a case 62 which may be a vegetable stand, dairy case, candy display case or other unit which does not require such low refrigeration as does the case in which the

evaporators

22 and 24 or other refrigerating means are located. In this way, the chilled ambient air from one case may be 4 utilized to increase the eiciency of the system and extend the usefulness thereof to other equipment.

As further shown in FIG. 4, the chilled ambient air from a passage 72 communicating with the duct means 34 may be directed by a blower '71 to the condenser '73 of the refrigerating unit 7S in a self contained refrigerated display case so as to increase the e'iciency thereof of the refrigerating unit by transfer of heat from the condenser to the air directed from the passage 72 to the condenser 73 by the blower '71.

In the further alternative form of the invention illustrated in FIG. 5, the chilled ambient air received from the duct means 34 at the rear of the lower front wall 10 of the case is blown over heating elements by a blower 82 and then is discharged through an outlet 84 near the bottom of the front wall 10 of the case. The air thus discharged has its temperature raised suilciently to overcome any objection thereto whereby neither children nor adults will be chilled by the cooled ambient air.

In each of the forms of the invention described above, the air approaching the lower edge of the access opening l2 of the display case is drawn off in a manner to prevent spillage of cooled air from the case and loss of refrigeration thereby. In fact, if desired, the inlet opening through which the chilled ambient air is drawn may be of such size or so located as to draw in unchilled ambient air for mixing with the chilled ambient air to temper or raise the temperature of the chilled ambient air until it is no longer objectionably cold when discharged from the case.

The present invention obviously may be used in combination with Various types of refrigerated equipment and with display cases maintained at temperatures above those usually employed in the preservation and display of frozen foods, ice cream and the like. It should, therefore, be understood that the particular embodiments of the invention shown in the drawings and described above are intended to be illustrative only and are not intended to limit the scope of the invention.

I claim:

1. A self-service refrigerated display case having a top, a bottom, end members and front and back walls eX- tending about a display space, the front of the case having an access opening therein and the upper edge of the front wall being positioned below said access opening, means for circulating refrigerated air forwardly and downwardly within the display space and adjacent said access opening, duct means located adjacent the front wall of the case in position to receive air moving for- Ywardly and downwardly adjacent said access opening, re-

frigerating means within said case, means for conducting one portion of the air received by said duct means to said refrigerating means for recirculation through said display space, and means for directing another portion of the air received by said duct means to the exterior of said display space.

2. A self-service refrigerated display case having a top, a bottom, end members and front and back walls extending about a display space, the front of the case having an access opening therein and the upper edge of the front wall being positioned below said access opening, means for circulating refrigerated air forwardly and downwardly within the display space and adjacent said access opening, duct means located adjacent the front wall of the case in position to receive air moving forwardly and downwardly adjacent said access opening, refrigerating means within said case, means dividing said duct means into two separate passages, one of which passages serves to deliver air to the exterior of the display space, and the other of which passages serves to return air to said refrigerating means for recirculation through the display space.

3. The combination as set forth in claim 2 wherein each of said passages is provided with a blower for moving air therethrough.

4. The combination as set forth in claim 2 wherein each of said passages is provided with an inlet located near the upper edge of the front wall of the case.

5. The combination as set forth in claim 2 wherein the passage which serves to return air to said refrigerating means is located rearwardly of the other passage.

6. A self-service refrigerated display case having a display space therein, means for refrigerating air, a passage through which air from said refrigerating means is circulated to said display space, an opening in said display case providing access to said display space, duct means communicating with the display space near an edge of said access opening, said duct means having a capacity exceeding that of said passage, means for circulating a portion of the air received by said duct means to said refrigerating means and passage for return to said display space, and means for circulating another portion of the air received by said duct means to the exterior of said display space.

7. A self-service refrigerated display case having a display space therein, means for refrigerating air, a passage through which air from said refrigerating means is circulated to said display space, an opening in said display case providing access to said display space, duct means communicating with the display space near an edge of said access opening, said duct means having a capacity exceeding that of said passage, means for circulating a portion of the air received by said duct means to said refrigerating means and passage for return to said display space, and means for circulating another portion of the air received by said duct means upwardly out of the top of the display case.

8. A self-service refrigerated display case having a display space therein, means for refrigerating air, a passage through which air from said refrigerating means is circulated to said display space, an opening in said display case providing access to said display space, duct means communicating with the display space near an edge of said access opening, said duct means having a capacity exceeding that of said passage, means for circulating a portion of the air received by said duct means to said refrigerating means and passage for return to said display space, and means for circulating another portion of the air received by said duct means to another display case.

9. A self-service refrigerated display case having a display space therein, means for refrigerating air, a passage through which air from said refrigerating means is circulated to said display space, an opening in said display case providing access to said display space, duct means communicating with the display space near an edge of said access opening, said duct means having a capacity exceeding that of said passage, means for circulating a portion of the air received by said duct means to said refrigerating means and passage for return to said display space, and means for circulating another portion of the air received by said duct means past a heating device to the exterior of the case.

10. A self-service refrigerated display case having a display space therein, means for refrigerating air, a passage through which air from said refrigerating means is circulated to said display space, an opening in said display case providing access to said display space, duct means communicating with the display space near an edge of said access opening, said duct means having a capacity exceeding that of said passage, means for circulating a portion of the air received by said duct means to said refrigerating means and passage for return to said display space, and means for circulating another portion of the air received by said duct means to a condenser for said refrigerating means and thence out of the case.

1l. A self-service refrigerated display case having a top, a bottom, end members and front and back walls extending about a display space, the front of the case having an access opening therein and the upper edge of the front wall being positioned below said access opening, blower means for circulating refrigerated air forwardly and downwardly witlr'n the display space and adjacent said access opening, duct means located on the exterior of the display space and having an inlet opening positioned adjacent the lower edge of said access opening and an outlet opening located adjacent said front wall of said display case, additional blower means for circulating air through said duct means from said inlet opening to said outlet opening, and means for raising the temperature of the air circulated through said duct means to said outlet opening.

12. In a refrigerated display case having a display space therein with an access opening facing toward the front of the display case and means for refrigerating articles located in said display space, a duct having an outlet opening through which air may be discharged from said case below said access opening, and means located adjacent said outlet opening for raising the temperature of the air discharged through said outlet opening.

13. In a refrigerated display case having a display space therein with an access opening in the front thereof, means for refrigerating and circulating air through said display space, duct means arranged to receive a portion of the air circulated through said display space, a blower for circulating said portion of the air circulated through the display space from the display case below said access opening, and means for raising the temperature of the air thus discharged from the case to a temperature above that of the air circulated through the display space.

14. A refrigerated display case having a display space therein with an access opening in the front thereof, means for refrigerating articles in said display space including refrigerating means, a blower and ducts through which air may be circulated to and from said display space and over said refrigerating means, said ducts having an outlet opening near the upper portion of said display space and an air return opening near the lower portion of said access opening, a second blower, other duct means having an outlet opening located below said access opening in the front of the display space through which air circulated by said second blower may be discharged from the display case to the area or aisle adjacent the front of said display case, and means for raising the temperature of the air discharged through the latter outlet opening.

15. A refrigerated display case having a display space therein with an access opening in the front thereof, means for refrigerating articles in said display space including refrigerating means, said refrigerating means having an evaporator and a condenser, a blower and ducts through which air may be circulated to and from said display space and over said evaporator, said ducts having an outlet opening near the upper portion of said display space and an air return opening near the lower portion of said access opening, a second blower, other duct means having an outlet opening located below said access opening in the front of the display space through which air circulated by said second blower may be discharged forwardly from the display space into the area or aisle adjacent the front of the display space, and means including said condenser for raising the temperature of the air discharged through the latter outlet opening.

References Cited in the le of this patent UNITED STATES PATENTS 2,066,312 Bales Jan. 5, 1937 2,673,455 Brinkoeter Mar. 30, 1954 2,706,387 Swanson Apr. 19, 1955 2,911,799 Guyton Nov. 10, 1959

Claims

1. A SELF-SERVICE REFRIGERATED DISPLAY CASE HAVING A TOP, A BOTTOM, END MEMBERS AND FRONT AND BACK WALLS EXTENDING ABOUT A DISPLAY SPACE, THE FRONT OF THE CASE HAVING AN ACCESS OPENING THEREIN AND THE UPPER EDGE OF THE FRONT WALL BEING POSITIONED BELOW SAID ACCESS OPENING, MEANS FOR CIRCULATING REFRIGERATED AIR FORWARDLY AND DOWNWARDLY WITHIN THE DISPLAY SPACE AND ADJACENT SAID ACCESS OPENING, DUCT MEANS LOCATED ADJACENT THE FRONT WALL OF THE CASE IN POSITION TO RECEIVE AIR MOVING FORWARDLY AND DOWNWARDLY ADJACENT SAID ACCESS OPENING, REFRIGERATING MEANS WITHIN SAID CASE, MEANS FOR CONDUCTING ONE PORTION OF THE AIR RECEIVED BY SAID DUCT MEANS TO SAID REFRIGERATING MEANS FOR RECIRCULATION THROUGH SAID DISPLAY SPACE, AND MEANS FOR DIRECTING ANOTHER PORTION OF THE AIR RECEIVED BY SAID DUCT MEANS TO THE EXTERIOR OF SAID DISPLAY SPACE.