Food service display cooler

Information

  • Patent Grant
  • 6539740
  • Patent Number
    6,539,740
  • Date Filed
    Friday, February 1, 2002
    22 years ago
  • Date Issued
    Tuesday, April 1, 2003
    21 years ago
  • Inventors
  • Examiners
    • Tapolcai; William E.
    • Ali; Mohammad M.
    Agents
    • Pettis & Van Royen, PA
Abstract
A food display cooler for display of packaged and non-packaged food products for self-service by customers. The cooler simultaneously provides a cooled frosted display platform and a blanket of cooled air above the display platform and over the food products. The display platform is pivotally mounted to a pan underlying the display platform. The display platform has a first cooling coil attached directly to the bottom surface of the display platform and a second cooling coil and a fan is connected to the display platform such that the cooling coil pivots with the display platform when it is pivoted to the open position. A refrigeration unit is connected in fluid flow communication with the cooling coil, and is connected to the exterior surface of the pan.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




The present invention relates to a food service display cooler for display of food products for self-service by customers. The cooler provides a cooled frosted display surface and a blanket of cooled air above the food products. The cooler is particularly structured for easy cleaning and service.




2. Description of the Prior Art




Display units for presentation of perishable foods are used throughout the food industry, including supermarkets and restaurants. These units include refrigerated shelves and display cases.




The refrigerated shelves are simple devices that include cooling coils attached to their bottom surface so that the products placed on the shelves are cooled from the bottom. This type of shelf frequently is cold enough to create a frost coating on the shelf surface. However, refrigerated shelves leave the upper portion of the food containers spaced too far apart from the cooling source permitting contact with warm ambient air, resulting in food spoilage.




Some refrigerated cabinets attempt to put a shield of cooled circulating air across the front of the cabinet to prevent the ingress of warm ambient air into the interior of the cabinet. The air current is not secure enough or complete enough to prevent the ingress of ambient air into the interior of the cabinet and to adequately cool the food products.




In refrigerated counter displays, the cooling is accomplished by maintaining a forced circulation of cold air over the display surface and the containers housing the food that are placed on the display surface. This is frequently unsatisfactory as the cooled air does not always flow over all the food products, as some food products are shielded from the air flow; therefore, cooled air may also be passed underneath the display surface.




Not withstanding the existence of such prior art refrigerated units, it remains clear that there is a need for refrigerated units capable of cooling the display platform, cooling the air above the display platform, restricting the flow of ambient air into the air above the display platform, and providing easy access to the fan, to the coils, and to the pan for cleaning and servicing purposes.




SUMMARY OF THE INVENTION




The present invention relates to a food service display cooler for presentation of packaged and unpackaged food products for self-service by customers. Most simply stated, the cooler of this invention comprises a pan having a bottom, at least one side and an exterior surface. The pan is mountable to a support, which may comprise a stainless-steel frame, wood cabinetry or any suitable support system. A display platform is pivotally mounted to the pan so that the display platform comprises a top for the pan. The display platform itself has a top surface and a bottom surface. A first cooling coil is attached to the bottom surface of the display platform and a second cooling coil and fan are connected to the bottom of the pan such that the two cooling coils and the fan pivots with the display platform when it is pivoted between a closed and an open position. A condensing unit is connected in fluid flow communication with both cooling coils, and is connected to the exterior surface of the pan.




The invention accordingly comprises an article of manufacture possessing the features, properties, and the relation of elements which will be exemplified in the article hereinafter described, and the scope of the invention will be indicated in the claims.











BRIEF DESCRIPTION OF THE DRAWINGS




For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings, in which:





FIG. 1

is an isometric view of the food service display cooler of this invention;





FIG. 2

is a cross-sectional front elevational view of the invention taken along line


2





2


of

FIG. 3

;





FIG. 3

is a cross-sectional right side elevational view of the invention taken along line


3





3


of

FIG. 2

;





FIG. 4

is the right side elevational view of

FIG. 3

, illustrating pivoting the display platform between a closed position and an open position and removal of the subpanels; and





FIG. 5

is a cross-sectional top plan view of the display platform of the invention taken along the line


5





5


of FIG.


2


.











Similar reference characters refer to similar parts throughout the several views of the drawings.




DESCRIPTION OF A PREFERRED EMBODIMENT




A preferred embodiment for the food service display cooler of this invention is illustrated in the drawing

FIGS. 1-5

, in which the apparatus is generally indicated as


10


. Referring first to the view of

FIG. 3

, it can be seen that the display cooler


10


comprises a pan generally indicated as


12


, a display platform generally indicated as


14


, a first cooling coil


16


, a second cooling coil


18


and a condensing unit


20


.




The pan


12


has a bottom


22


, an exterior surface


24


, and at least one side and is constructed from stainless-steel. In a preferred embodiment the pan may be any suitable shape, including cylindrical with a circular cross-section. In a preferred embodiment illustrated in the drawing figures, the pan


12


is rectangular and comprises a front side


26


, a left side


28


, a right side


30


and a backside


32


. Additionally, the pan


12


is covered by insulation


34


, which may be foam, fiberglass batting or other suitable insulating material. To protect the insulation and provide a more rigid structure, the insulation


34


is protected by a stainless-steel first cover


36


which is attached to the pan


12


.




The cover


36


is constructed with sufficient thickness to support attachment of frame


38


directly to the first cover


36


by welding the flanges


37


to the first cover


36


or the frame


38


may be attached by other suitable well-known means. The frame


38


is sized and configured to support the condensing unit


20


, which is mounted therein. In other embodiments, support members (not shown) may be installed between the pan


12


and the first cover


36


to provide additional support for the frame


38


.




The display cooler


10


is a drop in unit that may be mounted within any suitable cabinet


40


, which is shown in phantom. The cabinet


40


may also be constructed so that additional support may be provided to the frame


38


to support the weight of the condensing unit


20


. A top edge


42


joins the pan


12


to the first cover


36


. A rim


44


extends outwardly from top edge


42


so that the pan


12


rests upon the cabinet


40


to support the display cooler


10


. The rim


44


may be sealed to the cabinet to prevent food from passing into the interior of the cabinet and creating a biological hazard.




The display platform


14


is pivotally connected to the pan


12


by a pair of hooks


46


that are attached to opposing sides of the display platform


14


, as seen in FIG.


4


. Each hook


46


engages a corresponding pin


48


that is mounted to the adjacent portion of the interior of the pan


12


, by welding, bolting, or other well-known means. Each hook


46


comprises a hole


50


therethrough and an opening slot


52


that is sized to receive the pin


48


therethrough. Therefore, the display platform


14


and its attached coil and fan may be detached from the pan


12


for repair or other services.




The display platform


14


, as seen in FIG.


1


and

FIG. 3

, comprises a generally flat surface. In a preferred embodiment, the display platform


14


has a left edge


56


a right edge


58


, a front edge


60


and a rear edge


62


, that combined form the peripheral edge of the display platform


14


. Along that peripheral edge is formed a wall


64


that extends generally vertically upwardly along the right, left, front, and rear edges. The front portion of the wall


64


is angled upwardly, generally 15 degrees from the horizontal, to create a sloped front portion of the wall


64


. The wall


64


forms a well that keeps the food containers and any spillage on the display platform. A flange


66


extends outwardly from the front and side portions of the wall


64


so that the flange


66


engages the top edge


42


of the pan


12


and first cover


36


for support thereon. The front portion of the wall


64


is perforated forming a return vent


68


. As seen in

FIG. 1

, a rail


69


is attached along the front edge


60


of the display platform to prevent food products from covering the return vent


68


and to serve as a handle when pivoting the display platform


14


.




The first cooling coil


16


is formed from copper tubing, and at least a portion of its longitudinal length adjoins the bottom surface


70


of the display platform


14


, as seen in

FIG. 3

, and more clearly in FIG.


5


. The first cooling coil


16


is applied in a serpentine pattern, which may take any form as long as it evenly distributes the first cooling coil across the portion of the bottom surface that is desired to be cooled, or across all of the bottom surface


70


. The first cooling coil


16


is held against the bottom surface


70


by a number of copper plates


72


, that are tack welded or are attached by other well-known means to the bottom surface


70


. The first cooling coil


16


and the plates


72


are preferably formed from copper to take advantage of its high conductivity. The plates


72


increase the effectiveness of the heat transfer from the display platform


14


to the cooling coil, thereby evenly cooling the display platform


14


. To further improve the transfer of heat from the display platform, insulation


74


is applied to the bottom surface of the display platform covering the first cooling coil


16


. A second cover


76


is attached to the bottom surface


70


of the display platform


14


to protect the insulation material


74


.




This second cover


76


is constructed from sufficiently strong stainless-steel so that it is capable of supporting at least one fan


78


and the second cooling coil


18


that are attached thereto, and thus connected to the display platform, so that they are pivoted with the display platform. The fan


78


creates an airflow in accordance with the arrows shown in FIG.


3


. The airflow passes through the second cooling coil


18


thereby reducing the temperature of the air. Those skilled in the art will be able to determine the fan size needed to create the amount of airflow required to maintain the preferred air temperature above the display platform


14


that is needed to maintain the food at the temperature necessary to control the growth of bacteria in the food, without over cooling or freezing the food. Airflow is determined by fan size and speed. In a preferred embodiment, in order to distribute the airflow along the longitudinal length of the display platform and to fit the fans within the space available, four variable speed fans


78


are provided. The second cooling coil


18


is a standard cooling coil used for transferring heat in refrigeration systems, which preferably would include fins attached to the coils for more efficient heat transfer. The size of the cooling coil


18


will be determined by those skilled in the art based upon the heat load and the temperatures required.




In a preferred embodiment, a longitudinally extending U-shaped support


80


is used to attach the fan


78


to the second cover


76


, to support the second cooling coil


18


and to a guide the airflow through the cooling coil


18


. The U-shaped support


80


has two opposing sides


82


and a bottom


84


. A portion


86


of the bottom


84


is angled to more readily receive the return airflow through the fans. The sides


82


of U-shaped support


80


extends along the direction of airflow; and the end opposing the fans is open to permit airflow therethrough. A Z-shaped member


88


is mounted to the U-shaped support


80


so that it lies between the pan


12


and the bottom


84


of the U-shaped support


80


to prevent the airflow from bypassing the fans and bypassing the second cooling coil


18


. In other preferred embodiments, supports (not shown) may be attached to the display platform


14


and to the second cover


76


to prevent the weight of the U-shaped support


80


and the equipment mounted therein, from pulling the second cover


76


away from the display platform


14


.




An air duct


90


extends upwardly from a portion of one side of the pan, in a preferred embodiment, from the back side


32


. As seen in

FIG. 3

, the insulation material


34


extends upwardly adjacent to the air duct


90


to reduce the cooling loss. The front panel of the display cooler


10


forms the front of the air duct


90


. In a preferred embodiment, for ease of handling, the front panel is subdivided into two subpanels


92




a


and


92




b


. The air duct


90


has at least one vent formed in the subpanels that is aligned such that the airflow passes over the display platform


14


. As seen in FIG.


1


and

FIG. 2

, in a preferred embodiment, there are a plurality of vents passing through the subpanels


92




a


and


92




b


. Each subpanel


92




a


and


92




b


has first vents,


94




a


and


94




b


respectively, that direct a portion of the airflow upwardly and away from the display platform


14


, has second vents


96




a


and


96




b


, respectively, that direct a portion of the airflow downwardly toward the display platform


14


, and has third vents


98




a


and


98




b


, respectively, that comprises a plurality of apertures


100


, which permit a portion of the airflow to move laterally outwardly from the air duct


90


. The vents


96




a


and


96




b


lie intermediate vents


92




a


and


92




b


and


98




a


and


98




b


. This provides the most even flow of cooled air about the food products and food containers. The vents


98




a


and


98




b


provide cooling for the food products and food containers on the rear portion of the display platform


14


. The vents


96




a


and


96




b


are sufficiently raised and angled to provide cooled air to those food products placed on the middle of the display platform


14


and forward to the front of the display platform. The vents


92




a


and


92




b


are sufficiently high and the air is directed upwardly to provide cooled air to the food products and food containers on the front portion of the display platform


14


. This airflow also provides a curtain of air that helps prevent the ingress of ambient air onto the food products. As seen in

FIG. 3

, the airflow entering the duct


90


is directed first by a pair diverters


102


to assist movement of the airflow toward the sides of the air duct to provide an even flow of air across the vents. As can be seen in

FIG. 4

, the subpanels


92




a


(not shown) and


92




b


are removable. A channel


106


is attached to the top of the air duct


90


, and a U-shaped projection


108


is attached to the bottom edge


110


of each subpanel


92




a


and


92




b


. To install the panels, the top edge


104


of each subpanel is received in its corresponding portion of the channel


106


and each panel is lowered so that the U-shaped projection


108


captures a portion of the rear wall


56


that extends along the back edge


62


of the display platform


14


, thereby holding the panels in place.




In a preferred embodiment, the amount and direction of airflow passing through each of the three vents is controlled by an insert


95


attached to the back of the subpanels. The insert


95


comprises a hood


97


and a plate


99


. The hood is attached adjacent to the opening


101


of the second vents


96




a


and


96




b


and is angled downwardly to direct the airflow toward the top of the display platform


14


. The plate


99


is inserted between the subpanels and the back wall of the duct


90


. The spacing between the plate


99


and the back wall of the duct


90


determines the amount of airflow that is permitted to exit from the first vents


94




a


and


94




b


. Also, the upper portion


103


of the plate


99


is curved or angled in order to direct the airflow from the first vents


94




a


and


94




b


. In a preferred embodiment the upper portion


103


directs the airflow upwardly as it exits the first vents


94




a


and


94




b


, as seen in FIG.


3


. The number of apertures


100


through the subpanels will control the amount of airflow that is permitted to exit generally laterally through the third vents


98




a


and


98




b


. In a preferred embodiment, a sneeze guard


132


is mounted to adjacent wall structure as seen in

FIG. 4

, or it may be directly mounted to the display cooler


10


. The use of the sneeze guard


132


will affect the airflow over the display platform


14


, and may be used to direct the air downwardly toward the return vent


68


to keep the warmer ambient air from entering the space around the food and the food containers.




In a preferred embodiment, as seen in

FIG. 2

, one end


111


of a first 65 lb. gas shock


112


is pivotally attached to the left side


28


of the pan


12


and as seen in FIG.


2


and

FIG. 4

, one end


114


of a second 65 lb. gas shock


116


is pivotally attached the right side


30


of the pan


12


by brackets


118


. These brackets are attached to the pan


12


by welding or bolting. The other end


120


of the first gas shock


112


is pivotally attached to the left side of the display platform


14


and the other end


122


of the gas shock


116


is pivotally attached to the right side of the display platform


14


. The gas shocks


112


and


116


are attached to the display platform


14


by brackets


124


, which can be seen most clearly in FIG.


3


. The brackets


124


may be attached to the display platform


14


by welding or other suitable means. Sixty-five lb. gas shocks are suitable for the particular sized display cooler


10


illustrated in the drawings; however, those skilled in the art will be able to determine the appropriate size and power of the gas shocks needed for other embodiments of the display cooler


10


, based upon the weight of the display platform


14


and all the equipment that is attached thereto. The shocks


112


and


116


are installed to enable a person to easily lift the front of the display platform


14


and pivot it about the pins


48


. Those skilled in the art will be able to determine the proper positioning for the attachment of the ends


111


and


114


to the pan


12


, so that the force provided by the pistons may be properly applied to the display platform so that the display platform may be easily pivoted between its closed position and its fully open position.




The first cooling coil


16


and the second cooling coil


18


are each connected in fluid flow relationship with the condensing unit


20


by the insulated tubes


126


and power is provided to the fans through cable


128


. In a preferred embodiment, the cooling coils may be attached in fluid flow relationship in series to one another and to the condensing unit


20


. In another preferred embodiment, the cooling coils may be attached in parallel to the condensing unit


20


so that the temperature maintained in each cooling coil may be controlled independently. Those skilled in the art will readily be able to determine the size of the condensing unit


20


needed to support the maximum heat load on the display platform. The controls (not shown) necessary for operating the condensing unit


20


are mounted adjacent thereto. At least one temperature sensor


130


is connected to the control unit (not shown) and is mounted adjacent to the fan unit to measure the temperature of the return air so that the operation of the condensing unit may be automatically adjusted by the controls to maintained the proper temperatures.




Stainless steel is the primary material from which the display cooler


10


is constructed in order to meet cleanliness standards. In addition, welding is the preferred means for connecting parts together in order to provide a tight and smooth seal, again to enable easy cleanup of these parts. Certainly the condensing unit


20


, which is not in the food area, will be constructed from materials that are suitable for a standard condensing unit. As mentioned previously, the cooling coils


16


and


18


, as well as the plates


72


are constructed from copper due to its efficient heat conductivity. Cabinetry, which is not part of the display cooler


10


, may be constructed from wood, particularly decorative areas, stainless steel or other suitable materials.




Having thus set forth a preferred construction for the current invention, is to the remembered that this is but the preferred embodiment. Attention is now invited to a description of the use of the display cooler


10


.




The display cooler


10


is used to display packaged and unpackaged food products for self-service by the customer. The display cooler


10


is constructed to meet the National Sanitation Foundation standard #7, which provides the requirements for refrigerated food display.




The display cooler


10


may be mounted on a simple stainless steel cabinet. comprising a frame with legs, or on a more decorative cabinet made from stainless steel or wood. When the condensing unit


20


is in operation, air is circulated by the fan


78


through the cooling coil


18


through the duct


90


and out at least one vent. The amount of airflow is controlled by the number of fans, the fan speed and the fan sizes. The direction and quantity of flow of cooled airflow through the ducts is controlled insert


95


. Obviously, the number of fans and the size of fans is predetermined during the construction of a particular embodiment of the display cooler


10


. However, adjustments in the fan speed, and the spacing of the insert can be used to adjust the quantity and direction of airflow. Control of the quantity and direction of the airflow is essential to apply adequate cooling temperatures evenly to the food containers and the food therein. Also, providing a curtain of cooled air helps prevent the incursion of ambient air into the area above the food containers. The food containers will have a tendency to block horizontal airflow, therefore in order to cool the containers further away from the third vents


98




a


and


98




b


, airflow is projected outwardly and downwardly toward the front half of the display platform


14


to ensure that cooled airflow surrounds the containers toward the front of the display platform


14


. Airflow that is angled upwardly from the first vents


94




a


and


94




b


is projected further outwardly so that it can provide a curtain of air that will block the incursion of the warmer ambient air. The return of as much of the airflow as possible through the return vent


68


will help maintain the air curtain and the efficiency of the display cooler


10


. The use of the sneeze guard


132


will also redirect the airflow from the first vents


94




a


and


94




b


toward the return vent


68


further helping to block the incursion of warmer ambient air.




The first cooling coil, which is attached to the bottom of the display platform


14


, is operated at a temperature that is sufficiently cool to create a layer of frost on the top surface of the display platform upon which the food containers rest, which presents an attractive display. However, more importantly the direct cooling of the display platform


14


is essential to provide cooling of the food containers from the bottom so that in combination with the cooling that is provided by the cooled airflow across top of the display platform


14


, proper temperatures within the food can be maintained to prevent bacterial growth and thereby meet the food industry standards for safe handling of food products.




After the display cooler has been closed to customers, the food has been removed and the condensing unit


20


has been turned off so that the display platform has become sufficiently warm, the top surface of the display platform


14


is easily cleaned removing any food spillage. Now the subpanels


92




a


and


92




b


are removed so that the display platform


14


may be lifted and pivoted upwardly to gain easy access to the pan


12


. As the fans and second cooling coil


18


are connected to the display platform, they are pivoted out from within the pan


12


area leaving the pan


12


bare. Now the pan


12


may be easily and thoroughly cleaned, removing all food spillage to prevent the formation of bacteria. With the display platform


14


in the open position, as shown in

FIG. 4

, it will be easy to clean the fans


78


and the second cooling coil


18


to ensure that they are also clean. Most of the food spillage will occur through the return vent and between the flange


66


of the display platform


14


and the rim


44


of the pan


12


. The fan and cooling coil


18


is sufficiently spaced apart from the return vent


68


and is housed within the U-shaped support


80


, so most food spillage will be directly into the pan


12


for easy cleanup and little if any will contaminate the fan or cooling coil


18


.




While the foregoing describes particularly preferred embodiments of the present invention, it is to be understood that numerous variations and modifications of the structure will occur to those skilled in the art. Accordingly, the foregoing description is to be considered illustrative only of the principles of this invention and is not to be considered limitative thereof, the scope of the invention being determined solely by the claims appended hereto.



Claims
  • 1. A food service display cooler comprising:a pan having a bottom, a bottom surface and at least one side, said pan being mountable to a support; a display platform being pivotally connected to said pan such that said display platform comprises a top for said pan, said display platform having a bottom surface and a top surface; a first cooling coil having a portion of the longitudinal length thereof adjoining said bottom surface of said display platform and pivoting therewith; a fan connected to said bottom of said display platform such that said pan pivots therewith, said fan creating an air flow; an air duct extending upwardly from at least a portion of one side of said pan, said air duct having at least one vent therethrough aligned such that said air flow passes over said display platform; a second cooling coil connected to said display platform such that said air flow passes through said second cooling coil, through said duct, out said vent, and over said top surface of said display platform; and a condensing unit connected in fluid flow relationship to said first and second cooling coils.
  • 2. A food service display cooler as in claim 1, wherein said first and second cooling coils are connected in series, such that said first and second coils are in fluid flow communication with each other and with said refrigeration unit.
  • 3. A food service display cooler as in claim 1, wherein said first and second cooling coils are connected in parallel, such that each of said first and second coils are in fluid flow communication with said refrigeration unit.
  • 4. A food service display cooler comprising:a pan having a bottom, a bottom surface and at least one side, said pan being mountable to a support; a display platform being pivotally connected to said pan such that said display platform comprises a top for said pan, said display platform having a bottom surface and a top surface; a first cooling coil having a portion of the longitudinal length thereof adjoining said bottom surface of said display platform and pivoting therewith; a fan connected to said bottom of said display platform such that said pan pivots therewith, said fan creating an air flow; an air duct extending upwardly from at least a portion of one side of said pan, said air duct having a plurality of vents in said air duct, a first vent directing a portion of said airflow upwardly, a second vent in which a portion of said airflow is directed downwardly and a third vent comprising a plurality of apertures therethrough such that a portion of said airflow is directed laterally outwardly from said air duct a second cooling coil connected to said display platform such that said air flow passes through said second cooling coil, through said duct, out said vent, and over said top surface of said display platform; and a condensing unit connected in fluid flow relationship to said first and second cooling coils.
  • 5. A food service display cooler as in claim 4, wherein said second vent lies intermediate said first and third vents.
  • 6. A food service display cooler as in claim 4, wherein said first and second cooling coils are connected in series, such that said first and second coils are in fluid flow communication with each other and with said refrigeration unit.
  • 7. A food service display cooler as in claim 4, wherein said first and second cooling coils are connected in parallel, such that each of said first and second coils are in fluid flow communication with said refrigeration unit.
  • 8. A food service display cooler comprising:a pan having a bottom, a bottom surface and at least one side, said pan being mountable to a support; a display platform being pivotally connected to said pan such that said display platform comprises a top for said pan, said display platform having a bottom surface and a top surface; a first cooling coil having a portion of the longitudinal length thereof adjoining said bottom surface of said display platform and pivoting therewith; a fan connected to said bottom of said display platform such that said pan pivots therewith, said fan creating an air flow; an air duct extending upwardly from at least a portion of one side of said pan, said air duct having a second vent in said duct in which a portion of said airflow is directed downwardly and a third vent in said duct comprising a plurality of apertures therethrough such that a portion of said airflow is directed laterally outwardly from said air duct a second cooling coil connected to said display platform such that said air flow passes through said second cooling coil, through said duct, out said vent, and over said top surface of said display platform; and a condensing unit connected in fluid flow relationship to said first and second cooling coils.
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