This disclosure relates to the field of containers and cabinets that are configured to hold and maintain pre-cooked food product items warm and moist for later use by a kitchen or restaurant facility.
A first representative embodiment of the disclosure is provided. The first representative embodiment is a heated food storage container. The container includes a housing with upper and lower walls, right and left walls, a rear wall and defining an internal volume accessible through an open front portion. A heater and a fan are disposed within the housing and configured to deliver a flow of heated air through a ventilation duct defined within the housing. The ventilation duct includes an upper chamber, a rear chamber in fluid communication with the upper chamber, and a lower chamber in fluid communication with the rear chamber. A cowling is disposed upon a front portion of the lower chamber and configured to direct air flowing through the lower chamber in parallel with the lower wall to a second direction through the open front portion and toward an intake of the upper chamber. The cowling is configured to initially urge the air leaving the cowling at a first acute angle with respect to the lower chamber
A second representative embodiment of the disclosure is provided. The second representative embodiment is a heated food storage container. The container includes a housing with upper and lower walls, right and left walls, and a rear wall, the housing defines an internal volume accessible through an open front portion. A heater and a fan are disposed within the housing and are configured to deliver a flow of heated air through a ventilation duct disposed within the housing. The ventilation duct includes an upper chamber, a rear chamber in fluid communication with the upper chamber, and a lower chamber in fluid communication with the rear chamber. The upper chamber is defined between an internal upper wall and the upper wall, the rear chamber is defined between an internal rear wall and the rear wall, and the lower chamber is defined between an internal lower wall and the lower wall. A plurality of parallel beams are disposed upon the lower wall and support the internal lower wall, wherein the plurality of parallel beams define a plurality of separated air flow paths through the lower chamber, wherein each of the plurality of parallel beams is shaped as a truncated triangular member with a truncated end disposed proximate an exit of the lower chamber and an opposite second end disposed proximate an entrance into the lower chamber, wherein a heights of the second end is greater than a height of the truncated end.
Advantages of the disclosed container will become more apparent to those skilled in the art from the following description of embodiments that have been shown and described by way of illustration. As will be realized, other and different embodiments are contemplated, and the disclosed details are capable of modification in various respects. Accordingly, the drawings and description are to be regarded as illustrative in nature and not as restrictive.
a is the view of
Turning now to the figures, a heated food storage container, or cabinet 10 is provided. The container 10 is configured to receive and support multiple food storage trays or sheets within an internal volume 18 therein. In some embodiments, the container 10 may be capable of storing two conventional restaurant pans 2 therein, each disposed upon a separate vertically separated rack 4, as shown in
As best shown in
With reference to
The internal volume 18 is defined from an upper inner wall 21, a rear inner wall 22, a lower inner wall 23, a right inner wall 24, and a left inner wall 25. Each of the respective inner upper wall 21, inner rear wall 22, and the inner lower wall 23 are inwardly offset from the respective upper wall 11, rear wall 12, lower wall 13, such that an upper chamber 32 is defined between the upper wall 11 and inner upper wall 21, a rear chamber 34 is defined between the rear wall 12, and the inner rear wall 22, and a lower chamber 36 is defined between the lower wall 13 and the inner lower wall 23 (
In some embodiments shown in
The housing 20 additionally receives an arcuate and elongate cowling 42 (
In some embodiments, the cowling 42 is formed with an arc length greater than 90 degrees, but less than 180 degrees such air leaving the cowling 42 flows with a horizontal vector component directed into the internal volume 18 of the container 10. In some embodiments, the arc length of the cowling 42 may be between about 95 and 135 degrees, and more specifically between about 110 and 120 degrees, and more specifically about 115 degrees. Because of the arc length of the cowling 42, the flow of air leaving the cowling immediately leaving the cowling 42 is directed at an acute angle α with respect to the bottom wall 13 of the housing, and at a second, smaller, acute angle Δ between the angle of the outlet portion 42c of the cowling 42 and the inner lower wall 23. In some embodiments, the air leaves the cowling 42 in a range of about 50 and about 80 degrees with respect to the lower wall 13, inclusive of each individual angle within this range, in other embodiments, the air leaves the cowling 42 within a range of about 60-70 degrees, and in some embodiments the air leaves the cowling 42 at about 65 degrees or at about 60 degrees with respect to the lower wall 13.
As discussed elsewhere herein, the opening 32a into the upper chamber 32, leading directly to the suction of the one or more fans 62 is normally disposed proximate to the open front portion 19 and just within the internal volume 18. The opening 32a normally extends along the entire width of the housing 20 and provides suction along the entire length thereof to urge or assist the air leaving the cowling 42 to flow upwardly past the open front 19 of the internal volume 18 to establish the air screen 57 for the internal volume 18. The opening is normally disposed such that a line R between the outlet portion 42c of the cowling 42 and the opening 51 defines an acute angle β with respect to the lower wall 13 of the housing, wherein the acute angle β is larger than the angle α between the outlet portion 42c of the cowling and the lower wall 13.
A schematic representation of the air flow path through the housing 20 and ventilation duct 50 is depicted in
The upper chamber 32 is disposed generally in the upper portion of the housing and above the internal volume 18 of the housing 20. The upper chamber 32 includes one or more fans 62 that take suction through an opening 32a positioned within the inner volume proximate to an just behind the front opening 19. The opening 32a is normally a rectangular opening in the inner upper wall 21 or may be defined between a forward edge of the inner upper wall 21 and the front upper wall of the housing 27. The opening 32a normally extends along the entire length of the inner volume, such that an air screen 57 (i.e. the path of air flowing upwardly from the upper outlet portion 42c of the cowling 42 to the opening 32a) extends over the entire cross-section of the front opening 19.
In some embodiments and as shown in
In other embodiments, the baffle 65 may be configured with an outlet width that is larger than the length of the heating element 64 such that only a percentage of the air flowing through the upper chamber 32 (and therefore the air flowing through a single pass of the ventilation duct 50) flows past the heating element 64. This arrangement may be favorable when it is calculated that only a portion of the volume of air flowing through the ventilation system need be heated to maintain a relatively constant temperature within the internal volume 18 for each flow cycle based upon the size of the housing 20, nominal heat loss from the opening 18, through the walls, due to relatively colder food being placed within the internal volume, etc. The heating element 64 may be a conventional coiled heater, a heat strip, a radiator system, a gas burner, or another known heat input device.
The rear chamber 34 is fluidly connected to an exit of the upper chamber 32 (i.e. downstream with respect to the normal air flow through the ventilation duct 50) and is oriented substantially vertically, or at a small angle from vertical. The rear chamber 34 may allow for two air flow paths, a first flow path 52 directed from the upper chamber 32 to the lower chamber 36, and a second flow path 53 directing a portion of the air entering the rear chamber 34 to flow through a plurality of holes 22a disposed upon the inner rear wall 22 and into the internal volume 18. As can be understood by those of skill in the art that review and contemplate this specification, the percentage of air entering the rear chamber 34 that ultimately flows through the plurality of holes 22a and into the internal volume 18 may be a function of many factors, such as hole size, positioning, number of holes, inlet pressure, outlet pressure from the lower chamber 36, etc.
In some embodiments depicted in
In some embodiments and with some desired sizes and geometries of the container 10, it has been observed that a substantially constant air mass flow rate and a substantially small air temperature gradient along the width of the air curtain 57 has been established where each of the plurality of ribs 92 are disposed at differing acute angles (W, X, Y, Z) with respect to a line 3 parallel to the left inner wall 25. This substantially constant flow rate and uniform temperature profile has been observed in situations where constraints in the design and placement of the fan 62 prevent the output of the fan 62 from bisecting the centerline of the container 10, and/or the direction of air leaving the fan 62 is not directed along the centerline of the container 10. By way of example, it has been found that the substantially uniform air flow profile along the air curtain 57 was established when a first rib 92 was disposed at about 19 degrees with respect to the line and on a first side of the line 3, while the remaining three ribs 92 were disposed at about 4, 25, and 42 degrees, respectively, with respect to an opposite side of the line 3.
One of ordinary skill in the art, upon review and consideration of this specification, will contemplate that in situations where the output of the fan 62 bisects the centerline of the container 10 and/or the air flow from the fan 62 extends along the centerline of the container 10, the ribs 92 may be best placed at similar angles with respect to the line and on opposite sides of the line 3, with angles selected such that the increasing width of the air channels R, S, T is approximately the same as the embodiment discussed above. One of ordinary skill in the art will understand upon review and contemplation of this specification that the specific angles and orientation of the plurality of ribs 92 to achieve a substantially uniform air flow distribution and a substantially uniform temperature distribution across the air curtain may be achieved with optimized rib angles that can be determined with performance testing and optimization, but that the concept of providing a plurality of ribs 92 at differing acute angles with respect to a line 3 parallel to the left side wall 18 (or another wall or reference point that may be appropriate to establish a line along the rear chamber) to achieve this substantially uniform air flow and temperature profile is important in establishing the substantially uniform flow and temperature distribution across the air curtain 57. As can be understood, the differing acute angles (W, X, Y, Z) of the ribs may be both numerically different angles as well as falling on opposite sides of the line 3, or in other embodiments, pairs of ribs 92 on opposite sides of the line 3 may have the same magnitude of angle and be disposed upon opposite sides of the line 3.
The lower chamber 36 is defined between the inner lower wall 23 and the lower wall 23 and provides fluid communication between the rear chamber 34 and the cowling 42. The lower chamber 36 may have two air flow paths therethrough, a first path 54 receiving air from an outlet of the rear chamber 34 and directing the air to the cowling 42, and a second path 55 directing a portion of the air entering the lower chamber 36 into the internal volume 18 through a plurality of holes 23a disposed upon the inner lower wall 23. Each of the flow paths 53 and 55 allowing air to leave the ventilation duct 50 and enter the internal volume 18 are provided to establish some convective heat transfer within the internal volume 18 to maintain the temperature of the food product disposed within the internal volume 18 at a desired temperature. The percentage of air flowing from the lower chamber 36 and into the internal volume 18 is a function of the variables similar to those discussed above with respect to the percentage of air 53 that flows directly into the internal volume 18 from the rear chamber 34.
The inner lower wall 23 and the lower wall 13 are maintained in a separated orientation by a plurality of beams 70 that are disposed in parallel upon the lower wall 13 and are each fixed to a bottom surface of the inner lower wall 23. The plurality of beams 70 (
In some embodiments, the housing 20 may be configured such that the inner upper wall 21 is disposed substantially in parallel with the inner lower wall 23, and such that the inner rear wall 22 is substantially perpendicular with the inner lower and upper walls 23, 21 such that the internal volume 18 is substantially cubical.
Each beam 70 may be formed from any cross section that is configured to be mounted to both the bottom surface of the inner lower wall 23 (along the top edge 70c of the beam 70) and the inner wall 13 (along the base 70a) such that the beam 70 is configured to carry the weight of the inner wall 23 and fix the inner lower wall 23 to define the interior volume 18. In some embodiments as shown in
As best shown in
As shown in
Substantially uniform flow paths have been observed in embodiments where the common entrance 36e and the common exit 36f are each a length that accounts for about 7 percent of the total length of the inner lower wall 23. For example, in an embodiment where the inner lower wall 23 is about 16 inches deep, the plurality of beams 70 are each about 13.75 inches long and are centered forward to back upon the inner lower wall 23, leaving a common entrance and common exit 36e, 36f of about 1.15 inches.
In some embodiments, one or all of the plurality of beams 70 may include one or more side apertures 70g (as shown in
While the preferred embodiments of the invention have been described, it should be understood that the invention is not so limited and modifications may be made without departing from the invention. The scope of the invention is defined by the appended claims, and all devices that come within the meaning of the claims, either literally or by equivalence, are intended to be embraced therein.
This application claims priority from U.S. Provisional Application No. 61/393,124, filed on Oct. 14, 2010, the entirety thereof is hereby full incorporated by reference herein.
Number | Date | Country | |
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61393124 | Oct 2010 | US |