Patent Application
20240159394
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Field and Background of the Invention: The present invention relates generally to gas burners used to cook food products rapidly in commercial broilers, conveyor ovens, non-conveyor ovens having a fixed oven cavity, and toaster systems, and more particularly to an improved elongate gas burner and air delivery system for use in commercial broilers that utilizes a pressurized air unit to inject pressurized air near the flames of an elongate gas burner to guide heat downwardly to areas around and onto food product and to supply air (supplementing the primary air supplied for combustion) to enhance gas combustion and shape the flame to make it more efficient.
The present invention is an elongate gas burner and air delivery system for use in a multi-source cooking system that uses a pressurized air unit to deliver and introduce pressurized air into regions proximate an elongate gas burner: firstly, in a tertiary supply delivered through air outlets disposed in opposing linear arrays along each side of the burner element, spaced apart from the element to guide heat downwardly to areas around and onto food product; and, secondly, in a secondary air supply delivered through air outlets disposed in opposing linear arrays also along each side of the burner element to supply air to the combustion process in addition to the primary air to enhance gas combustion and shape the flame to make it more efficient in the open-ended cuboid combustion chambers of conveyor broilers. The secondary air may be tightly metered to ensure that there is just enough excess air to completely burn the fuel and, thereby, to enhance efficiency and reduce emissions. The array of air outlets for the secondary air is spaced apart from the burner at a distance proportional to the diameter of the burner and also proportional to the pressure under which the fuel is expelled; thus, it is tied to the flame locus so as to contribute optimally to oxygen input to enhance combustion.
The instant invention is an improvement on the systems disclosed in the following: U.S. Pat. No. 7,997,189, to Baker et al, which is directed to a heated compressed air broiler system; U.S. Pat. No. 8,272,320, also to Baker et al, which is directed to a broiler, conveyor oven and toaster system with pressurized air guide for heat and flames, each of which are incorporated in their entirety by reference herein.
The foregoing summary broadly sets out the more important features of the present invention so that the detailed description that follows may be better understood, and so that the present contributions to the technology may be better appreciated. There are additional features of the invention that will be described in the detailed description of the preferred embodiments of the invention which will form the subject matter of the claims appended hereto.
Accordingly, before explaining the preferred embodiment of the disclosure in detail, it is to be understood that the disclosure is not limited in its application to the details of the construction and the arrangements set forth in the following description or illustrated in the drawings. The inventive apparatus described herein is capable of other embodiments and of being practiced and carried out in various ways.
Also, it is to be understood that the terminology and phraseology employed herein are for descriptive purposes only, and not limitation. Where specific dimensional and material specifications have been included or omitted from the specification or the claims, or both, it is to be understood that the same are not to be incorporated into the appended claims.
As such, those skilled in the art will appreciate that the conception, upon which this disclosure is based may readily be used as a basis for designing other structures, methods, and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims are regarded as including such equivalent constructions as far as they do not depart from the spirit and scope of the present invention. Rather, the fundamental aspects of the invention, along with the various features and structures that characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the present invention, its advantages and the specific objects attained by its uses, reference should be made to the accompanying drawings and descriptive matter in which there are illustrated the preferred embodiment.
The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein:
Referring to
In embodiments the spaced plenums 16 are each elongate cuboids with an inverted V-shaped heat reflector and air outlet plate 32 on the underside 34 of the plenum defining an inverted V-shaped trough 36 along which the burner pipe extends. The combined burners and plenums are laterally disposed in parallel rows above the belt conveyor.
As is well known, the cylindrical burner pipe typically includes a linear array of fuel/air outlets 40 along which the fuel/air mixture is distributed and output for combustion into an essentially type A flame F. However, and essentially, the heat reflector/air outlet plate 32 is an inverted V-shape that includes two linear arrays of air outlets straddling the upper portion of the burner through which plenum air is output into the vicinity of the burner output to produce two distinct effects.
In the first instance, first and second (i.e., a pair of) outboard linear arrays of air outlets 42a, 42b, one each disposed in an angled side of the inverted V-shaped heat reflector/air outlet plate 32, straddle the upper portion of the burner to provide a low pressure curtain of downwardly directed pressurized air that guides and directs heat from the flame downwardly toward the cooking food product 26. This air curtain and heat guide system is described in detail in U.S. Pat. No. 8,272,320 to Baker et al, which, as earlier noted, is incorporated in its entirety by reference herein.
In the next instance, first and second (i.e., also a pair of) inboard linear arrays of air outlets 44a, 44b, one each also disposed in an angled side of the inverted V-shaped heat reflector/air outlet plate 32, direct low pressure air from the plenum through the heat/reflector air outlet plate, down and into the flame, thereby providing excess air to complete combustion, increase efficiency, and further shape the flame to optimize it for use in a cuboid cooking chamber. Spacing and dimensions of the inboard linear arrays of air outlets are a function of burner size, air outlet size, air pressure, and the like, but the general purpose of the combination of outlet arrays is to enhance combustion, and to that end good results have been found having the inboard linear arrays 44a, 44b, generally straddle the burner equal distances above and on each side of the burner and at a distance apart from one another substantially the same as the burner diameter, as can be clearly seen in
In an alternative embodiment, and referring now to
The technology of the present invention is incorporated in applicant's product models MV64 and FH94, which are dual belt, four lane gas flame conveyor broilers with automatic stack feeder for food product and the air supply system described above. Equipment testing of these models has shown exceptional and unexpected improvements in combustion efficiency, with corresponding reductions in broiler emissions and decreases in operating costs. Specifically, and as is considered more fully below, heavy-load cooking test data clearly show improved energy efficiency.
The public interest, as well as business interests in cost savings, ease of use, and pollution reduction, are benefitted by using the inventive system. Many energy utilities reward purchasers of energy efficient systems with rebates on purchase prices that match the energy savings. Equipment testing in a food service technology center was conducted on an implementation of the inventive system. In a dual belt conveyor broiler with four lanes, an automatic stack feeder, and the above-described burner configured with the gas, primary, secondary, and tertiary air supplies, data was collected to determine the energy input rate, preheat time and energy, idle energy rate, heavy-load cooking efficiency and production capacity using ASTM Standard Test Method F2239-10 (2021). In the case of the instant broiler, the savings (and the reduction in greenhouse gas emissions) is approximately 30%, and savings on commercial systems can therefore be substantial when both incentivizing rebates and the cost of energy consumption are considered. Indeed, the savings in the first year may represent a substantial portion of the entire purchase price of a system incorporating the inventive system. This is accomplished with no compromise (i.e., no increase) in cooking time.
A straightforward way to reduce the energy input in open broilers is to reduce the amount of fresh air that flows through the system, which also increases the overall heat to the unit. The liability in this approach is that it restricts a source of secondary air that needed for full and proper combustion from the burners: closing off the open front side makes the burners susceptible to incomplete combustion, and the flames become discontinuous across the burner surface. This problem is exacerbated when the broiler is under heavy cooking load because of the added effluent from the cooking food product, and this further starves the burner of oxygen.
By providing fresh air to the burners at the source of the flame, the inventive system may be closed to outside air while maintaining a stable burn, full combustion, and higher heat at comparable fuel consumption.
The above disclosure is sufficient to enable one of ordinary skill in the art to practice the invention and provides the best mode of practicing the invention presently contemplated by the inventor. While there is provided herein a full and complete disclosure of the preferred embodiments of this invention, it is not desired to limit the invention to the exact construction, dimensional relationships, and operation shown and described. Various modifications, alternative constructions, changes and equivalents will readily occur to those skilled in the art and may be employed, as suitable, without departing from the true spirit and scope of the invention. Such changes might involve alternative materials, components, structural arrangements, sizes, shapes, forms, functions, operational features or the like.
Therefore, the above description and illustrations should not be construed as limiting the scope of the invention, which is defined by the appended claims.
The present application claims the benefit of the fling date of U.S. Provisional Patent Application Ser. No. 63/383,787, filed 11/15/2022 (Nov. 15, 2022), which application is incorporated in its entirety by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| 63383787 | Nov 2022 | US |
