This invention relates to an improved container for holding beverages, food, and other items that require lengthy storage time with reduced heat gain or loss while maintaining freshness when no power source is available for refrigeration or heating.
Beverages, food, medical supplies, drugs and other heat sensitive products requiring storage without a power source have generally been stored in insulated coolers or ice chests for a very limited time period. Although these coolers or chests have certainly evolved over the years. For instance, U.S. Pat. No. 5,671,611 to Quigley dated Sep. 30, 1997, U.S. Pat. No. 5,568,735 to Newkirk dated Oct. 29, 1996, and U.S. Pat. No. 4,872,589 to Englehart dated Oct. 10, 1989. These all address the issue of preventing melted ice from coming into contact with the contents of the cooler allowing the contents to become soggy. Though each of the aforementioned patents provides a solution to the expressed problem of preventing melted ice from coming into contact with the contents of the cooler, it in no way prolongs the effectiveness of a cooler by keeping the contents' ambient temperature maintained for longer periods of time. The above patents address no efficient way of reducing the effects of radiant, convective or conducive heat, nor do they remove the decomposition effects of oxygen from the product storage area.
In U.S. Pat. No. 4,537,044 to Putnam dated Aug. 27, 1985 a more effective hot or cold food storage container is described which could take advantage of the physical movement of heat or cold. This container is designed so that a cooling source is above the food storage compartment for transferring cold in a descending direction while in cooling mode. A heat source is placed below the storage compartment for transferring heat in an ascending direction while in heating mode. Though this invention attempts to improve the effectiveness of a cooler it does not minimize the effects of radiation, nor does it eliminate conductive and convective heat while removing the decomposition effects of an oxygen environment by creating a vacuum in the product storage area.
Another invention described in U.S. Pat. No. 4,498,312 to Schlosser dated Feb. 12, 1985, which is designed to maintain hot or cold temperatures through use of solution filled slab-like panels. The slab-like panels, which provide the source of heat or cold, must be frozen or heated by an external source such as a freezer or oven. While the proposed invention could also incorporate cooling panels filled with water instead of a solution or ice, the above patent makes no use of a radiant barrier or a vacuumed containment area to prolong the desired temperature and maximize the freshness of the product.
U.S. Pat. No. 5,570,588 to Lowe dated Nov. 5, 1986 also uses solution filled slab-like panels or gel packs to maintain product at desired temperature. Again this patent makes no mention of minimizing radiant, conductive, and convective heat through the use of a vacuum sealed container nor does it remove the detrimental effects of oxygen.
The picnic cooler described in U.S. Pat. No. 5,064,088 to Steffes dated Nov. 12, 1991 incorporates a new lid design. The purpose of this cooler design is to improve the method of operating the cooler by allowing access to the container body in multiple ways without the use of hinges or latches. This invention is not intended to improve the efficiency of the cooler in the fact that it does not maintain the stored products' ambient temperatures.
U.S. Pat. No. 6,003,719 dated Dec. 21, 1999 to John R. Stewart III. Stewart sets out to improve the efficiency of the cooler by including radiant heat barrier and air space between an inner and an outer shell. While this design does a good job at reducing radiant heat, the described air barrier between the inner and outer shell is far less efficient at reducing conductive and convective heat than removing air molecules all together. In comparison, by removing the air molecules the proposed invention creates a far superior container while simultaneously removing the decomposing effects of oxygen this not only keeps products cold for longer periods of time, but it also maintains freshness.
U.S. Pat No. 6,295,830 dated Oct. 2 2001 to Michael D. Newman descries a tote for transporting refrigerated or frozen goods comprising an insulated container and a coolant insert. The insulated container includes a durable, impact-resistant shell, an insulation insert, an optional corrugated liner, and a cover. In this patent Newman has simply created a different form of coolant from which the container depends. This patent makes no mention of minimizing conductive and convective heat through the use of a vacuum sealed container nor does it remove the detrimental effects of oxygen.
U.S. Pat. No. 6,510,946 dated Jan 28, 2003 to Gena Gutierrez and Javier Gutierrez describes a vacuum Insulated Lunch Box with a rectangular box comprised of a top half and a bottom half, the top half and bottom half each having a double wall construction, and both having recessed areas to accommodate a plurality of food containers. Additionally, the top half and bottom half each having an outlet check valve, and the valves are capable of receiving a tube from a vacuum pump for the purpose of evacuating the cavity of each said lunch box half. A preferred embodiment includes further comprising a built in vacuum pump. In this invention Gena and Javier have employed the use of a vacuum to insulate a small lunch box that can contain no more than a day's meal instead of a cooler that is intended for long trips to sustain a large volume of products and not limited to food or beverages, furthermore, their patent has to create two separate vacuums in two separate compartments to maintain hot food and a cold beverage. The above mentioned patent makes no use of a radiation reflecting material and only addresses two out of three beat transfer modes. Since the food must be first put in to a container prior to being stored in the lunch box, it in no way prolongs freshness, since the vacuum space is separate from the storage areas and thus oxygen is still present where the food is actually stored.
Radiation is unique and independent form of heat transfer that basically refers to the transmission of electromagnetic energy through space. Infrared rays are not themselves hot but are simply a particular frequency of pure electromagnetic energy. Heat does not occur until these rays strike an object, thereby increasing the motion of surface molecules. The heat then generated is spread to the interior of the object through conduction. The radiation reflective material works by reflecting these infrared rays away from the interior of the cooler, thus reducing radiant heat in the containment or product storage area.
While reducing radiant heat contributes to the reduction of heat transfer, it does not address the effects of conductive or convective heat. Heat conduction, also called diffusion, is the direct microscopic exchange of kinetic energy of particles through the boundary between two systems. When an object is at a different temperature from another body or its surroundings, heat flows so that the body and the surroundings reach the same temperature, at which point they are in thermal equilibrium. Such heat transfer always occurs from a region of high temperature to another region of lower temperature, as described by the second law of thermodynamics. On a microscopic scale, heat conduction occurs as hot, rapidly moving or vibrating atoms and molecules interact with neighboring atoms and molecules, transferring some of their energy (heat) to these neighboring particles. In other words, heat is transferred by conduction when adjacent atoms vibrate against one another, or as electrons move from one atom to another. Conduction is the most significant means of heat transfer within a solid or between solid objects in thermal contact and convection is usually the dominant form of heat transfer in liquids and gases, based on the phenomena of movement between fluids. Basically, a moving fluid or gas transfers more energy to another substance or object when it is moving around it rather than being stationary.
By creating a substantial vacuum in the cooler the stored product's capacity to transfer or receive energy via conduction or convection thru air molecules is substantially limited due to the fact that there are no longer air molecules in the vicinity of the stored products to facilitate such a transfer.
Air consists of 78% nitrogen, 21% oxygen, and a 1% mixture of other gases. While oxygen is essential for life, it can have deteriorative effects on fats, food colors, vitamins, flavors, and other food constituents. Basically, oxygen can cause food spoilage in several ways; it can provide conditions that will enhance the growth of microorganisms; it can cause damage to foods with the help of enzymes; and it can cause oxidation. Molds and most yeast that cause food to spoil require oxygen to grow. By creating a substantial vacuum in the cooler assembly the detrimental effects of an oxygen rich environment are greatly reduced due to the fact that oxygen is no longer present.
The invention will be best understood, together with additional advantages and objectives thereof, from the following descriptions, read with reference to the drawings in which:
10 cooler lid assembly
12 cooler lid gripping handles
14 cooler assembly
16 vacuum pump handle
18 vacuum release button
20 radiation reflecting material
22 cooler assembly handle
24 perforated interior shell wall
26 perforating holes
28 perforated cooler lid shell wall
30 seal
32 vacuum pump assembly
34 vacuum pump exhaust
36 vacuum pump intake
38 spring
40 plunger
42 outside air exhaust
44 outside air intake
46 plunger shaft
48 vacuum release assembly
50 exterior shell
52 perforated reinforcement member
54 product storage area
56 vacuum space
58 non perforated shell wall
Various embodiments of the invention are described by reference to the drawings in which like numerals are employed to designate like parts. Various items of equipment that could be additionally employed to enhance functionality and performance such as fittings, mountings, sensors (e.g. temperature gages), etc., have been omitted to simplify the description. However, such conventional equipment and its applications are known to those of skill in the art, and such equipment can be employed as desired. Moreover, although the invention is described below in the context of the transport and storage of products that are sensitive to heat transfer and degradation due to oxygen present atmosphere, those skilled in the art will recognize that the invention has applicability to the transport and/or storage of many different refrigerated or frozen products or items, e.g. medical supplies, biological material, chemicals, and the like.
Referring to
The present application is a continuation of Ser. No. 15/046,919, entitled “Vacuum Cooler” and filed on Feb. 18, 2016, which is a continuation of U.S. patent application Ser. No. 13/562,828, entitled “Vacuum Cooler” and filed on Jul. 31, 2012, now U.S. Pat. No. 9,296,543, which are hereby incorporated by reference in their entireties for all purposes.
Number | Date | Country | |
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Parent | 15046919 | Feb 2016 | US |
Child | 15897348 | US | |
Parent | 13562828 | Jul 2012 | US |
Child | 15046919 | US |