Field of the Invention:

[001] This invention relates to keeping food dry. In particular, this invention relates to keeping food from absorbing ambient moisture and becoming soggy.

Background:

[002] Food stored temporarily for delivery, or stored long term, can be ruined by condensation forming on the food. If hot food is placed in a container, hot vapor, including air and water, rises upward from the food.

[003] Other inventions, such as United States patent application for a Container US20120024859A1 (Longoni et. al) try to vent wet vapor, which allows heat to escape. These vented container solutions are marginally effective at removing moisture, i.e. condensation, while allowing cold ambient air to quickly cool the food.

Summary

[004] This invention removes air moisture from inside a hot food container by first straightening the convection air flow rising above hot food, and second redirecting the rising air at a sharp turn, forcing the momentum of the heavier water-laden air to continue a straight trajectory into an absorbent pad or similar material, where the water from the air collides with the absorbent surface and is trapped. In this way, the invention extracts water from the air, before it can condense on food, thereby preventing the food to from becoming soggy.

[005] The invention is embodied in a food storage comprising four principal elements: (a) a housing for enclosing hot food, (b) a plurality of parallel passageways mounted inside the housing, (c) an absorbent layer positioned above the plurality of parallel passageways, and (d) a gap between the plurality of parallel passageways and the absorbent layer. Brief Description of the Drawings

[006] The objects, features and advantages of the present invention will be more readily appreciated upon reference to the following disclosure when considered in conjunction with the accompanying drawings, wherein reference numerals are used to identify the components in the various views.

[007] Fig. 1 illustrates a perspective view of a pizza box embodiment with an open lid.

[008] Fig. 2 illustrates a perspective view of the pizza box of Fig. 1 cut along A- A.

[009] Fig. 3 illustrates a side view of the pizza box of Fig. 1 cut along A-A.

[010] Fig. 4 illustrates a section view of a closed pizza box embodiment.

[011] Fig. 5 illustrates a bottom perspective view from inside the pizza box of Fig. 4.

[012] Fig. 6 illustrates a perspective view of the preferred embodiment of (a) a plurality of parallel passageways for mounting inside the housing, (b) an absorbent layer positioned above the plurality of parallel passageways, and (c) a gap between the plurality of parallel passageways and the absorbent layer.

[013] Fig. 7 illustrates a side view of the preferred embodiment of the invention shown in Fig. 6.

[014] Fig. 8 illustrates an embodiment for creating the plurality of parallel passageways.

[015] Fig. 9 illustrates an embodiment located within a clamshell-type to-go box.

[016] Fig. 10 illustrates a section view of a closed pizza box embodiment with arrows showing how air flows inside the box.

Detailed Description of Preferred Embodiment

[017] A preferred embodiment of the invention is shown in Figs. 1- 7. The invention is embodied in a food storage device 10 comprising four principal elements: (a) a housing 14 for enclosing hot food, (b) a plurality of parallel passageways 18 mounted inside the housing 14, (c) an absorbent layer 22 positioned above the plurality of parallel passageways 18, and (d) a gap 26 between the plurality of parallel passageways 18 and the absorbent layer 22.

[018] The housing 14 would typically be a fast-food container, such as a pizza box or a Styrofoam takeout box. But it could be any container that houses food. For example, the housing 14 could be a plastic container with a press-fit lid, it could be a cardboard box, or it could be a more rigid container. A pizza box embodiment is shown in Figs. 1-5 and a clam-shell style embodiment is shown in Fig. 9.

[019] The plurality of passageways 18 could be shaped in a variety of ways. The preferred plurality of parallel passageways 18 is created by a flow-straightening grid 48 as shown in Fig. 5. But any structure that straightens air flow would work. Flow straighteners are well-known to those in the art. The passageways 18 could be hyperboloids, venturis, cylindrical tubes, hex tubes, square tubes, etc. It is preferred that the parallel passageways be at least 0.5 inches long, though the length is ideally determined by the ratio of the length of the tubes divided by the hydraulic diameter of the tube cross sectional shape. This length divided by hydraulic diameter ratio is preferred to fall within the range 4 to 9. In addition, screens, in lieu of tubes, are also effective at decreasing turbulence. Screens are less effective than tubes at straightening the air flow but offer an economical embodiment with the same benefits, diminished such as they are.

[020] A preferred embodiment of the plurality of passageways 1 is shown in Fig. 8. As illustrated, this embodiment is made by starting with a comb-shaped piece 40. The comb-shaped piece 40 has a plurality of slots 42. The comb-shaped pieces can be fit together to form a grid 48, which results in a plurality of parallel passageways 18 as shown in Fig. 8.

[021] An alternate embodiment for the plurality of parallel passageways 18 (aka flow straightener) may be more elaborate than the square channel system illustrated. Ideal hyperboloid chimney geometry has the benefit of accelerating the hot (wet) vapor beyond the air flow (velocity) crated by natural convection. This accelerated flow means increased momentum; meaning more water extraction. [022] Another alternate embodiment for the passageways 18 could invoke venturi principles to accelerate the airflow beyond the limits of natural convection air flow, increasing momentum and increasing the efficacy of water extraction from the air. Dry air turns and flows unhindered by water as it exits the flow straightener and then returning to a container's air volume below. By drying the air, without venting, the food is dyer, to be certain, but it is hotter. Venting food containers allows colder ambient air to enter food containers and subsequently cool the food.

[023] Another important element of the invention is the gap 26 between the exit end 34 of the parallel passageways 18 and the absorbent layer 22. This gap 26 allows lighter dry air to turn and avoid the absorbent layer 22. Wet, heavier air has too much momentum to make this same turn as the dry air. The linear momentum of the wet air propels it, i.e. slings it, into an absorbent layer 22, which traps the water. This inertial water separator creates a dryer environment inside the sealed food container.

[024] The absorbent layer (i.e., hygroscopic element) 22 may be made from any absorbent material, such as airlaid, sponge, cotton, paper, hemp, linen, plant cellulose, etc.

[025] The device can be constructed in various ways. It is preferred to construct the plurality of parallel passageways 22 from cardboard in a shape that creates a relatively rigid “honeycomb.” An embodiment of the plurality of passageways is shown in Fig. 8. While a rectangular grid-like shape is presently preferred, other configurations could also work. The grid can be constructed from a variety of materials including metal, cardboard, still paper, or any other material that can hold a grid-like shape.

[026] The gap 26 can be created using bracket 30 to keep a fixed distance between the absorbent layer 22 and the exit end 34 of the passageways 18. It is preferred to use cardboard for the brackets 30. One end of the bracket 30 is preferably connected to the plurality of parallel passageways 18 using an adhesive or other known fastener. The other end of the bracket 30 can be connected to a plate 38 that is connected to (and holds) the absorbent layer 22. The brackets 30 create the gap 26. Plate 38 can then be connected to the inside face of the food container via adhesive or other connecting material known in the art. [027] In an alternative embodiment, the air gap 26 at the exit 34 of the flow straightener can be larger at the perimeter of the grid and smaller at the center of the grid. This varied gap 26 allows for easier airflow of the dry air as it moves outward away from the center. The dry air will naturally mix with the rest of the air inside the food container.

[028] The embodiment illustrated in Figs. 1-7 preferably uses an adhesive surface to secure/attach both the absorbent element and the cardboard brackets which suspend the cardboard flow straightening grid.

[029] The preferred material for this embodiment is cardboard for the flow straightener grid and the brackets, and there are many adhesive options, should an adhesive be used to secure the assembly to the inside of the food container. In lieu of brackets to suspend the flow straightener, it may be held in place with locking tabs, or Velcro, buttons, snaps, guy wire, elastic, etc. What is important is the gap 26. It is preferred that the gap 26 be at least 0.5 inches.

[030] As illustrated by Fig. 10, ambient moisture from inside a hot food container rises 50 from the food 52. After straightening the convection air flow rising above hot food via the parallel passageways 18, drier air makes a sharp turn 54. The heavier water-laden air to continues a straight trajectory into an absorbent pad 22 or similar material. In this way, the invention extracts water from the air, before it can condense on food, causing the food to become soggy.

[031] While the invention has been described by means of specific embodiments, numerous modifications and variations could be made thereto by those ordinarily skilled in the art without departing from the score and spirit disclosed herein.