Embodiments of the present invention relate to lighting applications, especially pre-existing work lighting applications that employ incandescent lamps, wherein the otherwise placement of the light source is in an area that is too hot for the efficient use of newer lighting technology, or wherein the present lighting source is non-directional in nature, and the overall luminaire function would benefit from the use of a more energy-efficient more-directional light source.
In the preferred embodiment of the present invention, the field of the invention is more related to food hospitality markets, especially lighting applications that relate to hotplate food storage and staging areas, and hot food display and dispensing fixtures and work areas commonly requiring light sources which operate in elevated ambient temperatures.
Neither this application nor the applicants hereto are subject to release of any rights to inventions made under federally sponsored research and development.
Copyright 2013 by ChefLED Inc. This patent application and any resulting issued patent contains material that is subject to copyright protection. The owner has no objection to the facsimile reproduction by anyone of the application or the issued patent, as it appears in the Patent and Trademark Office patent file or records. However, the owner otherwise reserves all copyrights whatsoever.
Stainless steel cabinets and work surfaces are commonly found in the food preparation and hospitality industry because of their durability and ability to be easily cleaned. Some of these cabinets and work surfaces are heated either directly or indirectly in order to keep hot food hot, or to cook the food while placing it on display.
Infra-red heating is one common energy form used to indirectly heat or cook food. This is often true in restaurants that utilize infra-red heaters to create “hotplate areas” that indirectly warm plates and food as it is assembled by kitchen staff, and then to keep said plate and food warm while it awaits pick-up by waiters and floor staff.
One very common configuration of the infra-red warm food preparation and assembly area consists of a stainless steel surface that can accommodate plates lined-up next to each other, and installed directly above said surface is a second stainless steel assembly in the form of a hood that sits above the plates.
Within this hood assembly the infra-red heaters are mounted, typically within a mechanical channel, and also commonly sits a set of light bulbs which also sit within a common stainless steel channel.
The lighting channel typically consists of a u-shaped folded stainless steel sheet, to which a plurality of high-temperature lamp sockets are mounted so as to have the lamp bulbs mounted in the horizontal plane—in parallel to the stainless steel sheet. In this way light is direct down towards the food.
The light bulbs themselves are specialty glass-enclosed incandescent light bulbs that are specially manufactured to operate in high ambient temperatures, and said glass enclosures are further covered in plastic to prevent glass from contaminating food should a bulb be broken.
These bulbs operate in high ambient temperatures because the infrared heaters and hardware heat-up local air currents creating significant convective heat that wishes to rise and therefore gets trapped in the infra-red and lighting channels. Additionally, infra-red waves emanating from the infra-red heaters are directed towards the food where some of the energy in the waves is also converted from radiant heat into convective heat, and this convective heat again rises. Furthermore, some of the radiant infra-red wave energy misses the food surface and is instead reflected back up towards the hood assembly. Over time, the hood assembly begins to heat-up, and temperatures within the lighting channel can exceed 300 to 350 degrees Fahrenheit.
Because of the elevated ambient temperatures, the lifetime of the incandescent lamp is shorten, and as these specialty lamps are expensive both in terms of energy usage and cost to purchase, the industry could benefit greatly if they could use newer lighting technology. However, newer light technology that relies on chemical phosphors such as light-emitting diodes, are temperature sensitive when it comes to lifetime and emitted color temperatures, and therefore are not easily a replacement for the specialty bulb. Additionally, modifying the stainless steel fixtures to accommodate mounting some other form of luminaries is both expensive and troublesome given the food regulations and food preparation safety requirements.
A unique and special light bulb is designed. The light bulb is so designed so that it can be inserted and removed from the existing horizontally mounted light bulb sockets without modification to the lamp sockets or the stainless steel fixtures, greatly reducing installation costs and minimizing compliance and inspection requirements of the food safety agencies.
The light bulb employs a directed light source to minimize light energy that is otherwise misdirected or reflected at greater loss. The light bulb makes use of a modern energy-efficient light source generator and a specially designed heat sink to maximize dissipation of locally generated heat from that light source.
The light bulb further employs a complex mechanical mechanism to accomplish two design goals and requirements: The light emitter needs a means to direct light to the target work surface, and a second means for the heat sink of said light emitter to be so positioned as to be located outside of the lighting channel, thus avoiding the highest generated thermal temperatures.
The heat sink of the light emitter is further designed to minimize surfaces exposed to directly radiated infra-red energy from the infra-red generators, as well as surfaces exposed to surface-reflected infra-red energy emanating from the food plate surface.
The heat sink design further maximizes the use of air current channels designed to take advantage of the mixing of air currents by the thermal layers, said channels limited in scope and size by governmental and non-governmental food safety regulations and cleaning requirements.
The light-emitter end of the bulb is sealed with a clear lens assembly that may or may not have a light focusing or light distribution function. Said clear lens seals the light assembly and facilitates easy cleaning as required by governmental and non-governmental food safety agencies.
The mechanical adjustment mechanisms are so designed to maximize physical robustness of the lamp bulb as well as maximize protection of the current-carrying wires located within the bulb assembly. Furthermore the surfaces of said mechanical swivel and angle assembly are so designed as to minimize the ability to house or attract food, dirt, oils, or dust, and to facilitate easy cleaning.
The drawings, which are incorporated herein, illustrate the background of the invention and one or more embodiments of the present invention, thus helping to better explain one or more aspects of the one or more embodiments. As such, the drawings are not to be construed as limiting any particular aspect of any embodiment of the invention. In the drawings:
As used throughout this specification and claims, “warm food preparation and assembly area” and “hotplate assembly area” are used as general terms to describe areas or assemblies of furniture or fixtures wherein hot food may be kept warm either during the plate assembly process, such as when a potato may be added to a plate that already has a steak placed on it, or when meals have been plated and ready to deliver to a table, but floor staff have yet had time to make said delivery.
As used throughout this specification and claims, “warm food preparation and assembly area” and “hotplate assembly area” or any other similar wording used in examples should not be construed as limiting the application of the invention. Indeed, application of the invention to open or enclosed hot dog cooking and display cases, popcorn machines and display cases, and all other applications of the invention that would benefit from the increased ambient temperature operation capabilities of the LED or OLED light source are anticipated. Furthermore, applications of the invention that benefit solely from the ability to direct the emitted light even without the need for increased ambient operation are also anticipated.
In
Also in
Also in
Because of governmental and non-governmental food safety regulations and agencies, bulb 250 is a glass bulb that is in turn encased in a high temperature plastic casing, so that the chance of glass being introduced into food should the bulb break is minimalized.
In
Continuing in
420 points to the lighting channel as discussed previously, but this time one embodiment of the invention 450 is installed in the channel instead of an incandescent lamp. As previously noted, the ambient temperature in lighting channel 420 can reach 300 degrees C. near the top of the channel. 460 illustrates the bottom edge of the channel, where the ambient temperature of this thermal layer is 85 degrees C. or less. Taken together,
In
520 is the primary heat sink to which the LED light engine 510 is mounted to, and the lens assembly 500 snaps into and seals against. A thermally-conductive compound (not illustrated) is applied between the bottom of the 510 LED light engine and printed circuit board, and the inside surface of the 520 heat sink to which the 510 fits into, thus further assuring maximum thermal conductivity from the LED die on 510 circuit board to the 520 heat sink. The 520 heat sink is so designed to minimize surfaces that are directly exposed to infrared wave energy including the bottom ring edge of the heat sink to which the 500 lens sits into and seals. The outside surface of the heat sink is ribbed to maximize surface area for thermal transfer to the ambient temperature air the 520 heat sink sits in, yet said ribs are of such design so as to minimize collection of food particles or grease, and facilitate ease of cleaning.
Still in
540 of
The second axis of adjustment of the 540 of
550 of
Finally in
What is not illustrated in
In
730 and 740 are two subassemblies of the 540 multi-part metal assembly that permits two axis of movement or adjustment. The 740 is the sleeve portion that allows for rotation in the 750 housing of up to 350 degrees along the main axis, and the 730 is the swivel joint that facilitates a bending off from center of 110 degrees.
760 is a side view of the Edison plug.
Furthermore,
It is also anticipated that in some applications a Peltier-effect cooler operating as a solid state thermoelectric heat pump in conjunction with the invention's heat sink may be desired or necessary to meet operating parameters of some applications. Said solid state thermoelectric heat pump sandwiching itself between the
It is also anticipated that in some applications it will be desirable to extend the distance from the light head assembly and the plug, and therefore an a third axis of adjustment of the invention is anticipated.
This application claims priority to and the benefit of the filing of U.S. Provisional Patent Application Ser. No. 61/ 796,052, entitled “LED light with swivel head”, filed on Nov. 1, 2012, and the specification thereof is incorporated herein by reference. This application is further related to Non-Provisional Patent Application Ser. No. 29/ 421,970, entitled “LED light with rotating and swiveling head”, filed on Nov. 1, 2012, and the specification thereof is incorporated herein by reference, and any benefits that may exist are claimed.