Patent Application
20060147865
The present invention relates to gas fired cooking ranges and, more particularly, to burner head assemblies used in such ranges.
Gas fired cooking ranges have achieved wide acceptance in both residential and commercial kitchens. A known design for gas fired cook tops in ranges includes separate burner assemblies for each cooking location, with each burner assembly including a venturi and a burner head having gas-emitting orifices. It is known to arrange the orifices so that the flames are spread widely, and are directed across the bottom surface of a vessel placed on a grate above the burner. These burners have included orifices in outwardly facing surfaces of the burner head, so that flames are directed outwardly from the burner head. A disadvantage of this design is that the outermost orifices are exposed to fouling from boil-overs and spills in which food can flow along outer surfaces of a cooking vessel above the burner and drip from the vessel onto the burner head.
Factors such as flame intensity and efficiency, burner assembly cleanability and fuel consumption efficiency are important to both residential and commercial installations. However, these factors may be of greater importance for commercial kitchens where a great number of meals may be prepared on each cook top in a relatively short period of time. The time required for completing a food course, including initial preparation time for heating and actual cooking time, can be reduced by efficient burner performance. If the flame from a burner spreads outwardly beyond the vessel being heated, or wicks up the side of the vessel, heat transfer efficiency decreases. Since commercial kitchens can be hectic environments, boil-overs and spills are common. Therefore, cleanability is important, and it is advantageous to reduce the time required for disassembling and reassembling the cook top for thorough cleaning. Maintaining burner performance in spite of spills and boil-overs during food preparation is also important.
What is needed in the art are burner assemblies that are reliable, use fuel efficiently, heat vessels quickly and can be disassembled and reassembled efficiently for thorough cleaning of the cook top.
The present invention provides a two-piece burner assembly with an annular base and cover. Gas-emitting orifices are provided in the cover only in upwardly and/or inwardly facing surfaces. A restrictor plate positioned within the annular burner controls the flow of secondary air for efficient burner performance.
In one aspect thereof, the present invention provides a gaseous fuel burner assembly with a venturi and an annular burner head associated with the venturi for the combustion of gaseous fuel from the venturi. The burner head has outwardly facing, upwardly facing and inwardly facing surfaces. The burner head defines gas-emitting orifices only through the upwardly and/or inwardly facing surfaces of the burner head.
In another aspect thereof, the present invention provides a gas fuel burner head with a substantially annular base and a substantially annular cover having gas-emitting orifices on only upwardly and/or inwardly facing surfaces of the cover. A restrictor plate limits the flow of air through the center of the substantially annular base and top.
In a still another aspect thereof, the present invention provides a burner head with a substantially hollow annular body directing gas flow therethrough. The body has only upwardly and/or inwardly facing orifices for emitting gaseous fuel to be burned. The flow of air through the substantially annular body is controlled.
In a further aspect thereof, the present invention provides a burner head with a substantially annular burner head base having inner and outer base edges and defining an annular open top channel for directing gas flow therethrough. A substantially annular cover on the base has inner and outer cover edges engaging the inner and outer base edges, respectively. The inner cover edge has an inner lip with an angular surface facing downwardly and laterally for positioning the cover on the base, with the inner lip disposed along the inside of the substantially annular base.
In a still further aspect thereof, the present invention provides a burner assembly for an open top cooking range with a monolithic body forming first and second gas receiver ends, first and second venturis and first and second burner head bases. First and second burner head covers are engaged removably on the first and second burner head bases.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features.
Before the embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use herein of “including”, “comprising” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof, as well as additional items and equivalents thereof.
Referring now more specifically to the drawings and to
Range 10 is a gas fired range, having a gas circuit (not shown) for supplying combustible gas to each burner assembly 12 provided at several cooking locations on cook top 14, and to an oven burner assembly, not shown, for heating the interior of oven 16. As those skilled in the art will understand readily, range 10 has a plurality of flow control valves 18 for initiating, terminating and controlling the rate of gas flow to cooking locations on cook top 14. Range 10 is supported on casters 20, by which range 10 can be moved a short distance to clean the area around the range.
Burner head assembly 12 includes a first burner head 22 and a second burner head 24 at which combustion of gaseous fuel occurs. A single piece, monolithic casting 30 forms a first venturi 32 associated with a first burner head base 34 and a second venturi 36 associated with a second burner head base 38. First venturi 32 and second venturi 36 provide a flow of gas and primary combustion air for combustion at first and second burner heads 22, 24, respectively, in front and back locations, respectively, on cook top 14. First and second gas receivers 40, 42 are provided on first venturi 32 and second venturi 36, respectively. As known to those skilled in the art, each receiver 40, 42 is aligned with a different control valve 18 to receive gas therefrom when the control valve 18 is opened to allow gas to flow therethrough. Receivers 40, 42 also admit a flow of ambient air to mix with the combustible gas in first venturi 32 and second venturi 36 to provide a combustible mixture to burner heads 22, 24.
In the embodiment illustrated, first venturi 32 and second venturi 36 are configured with first burner head base 34 and second burner head base 38, respectively, to swirl the combustion mixture in opposite directions. In the embodiment shown in
Burner head 24 and the components thereof can be seen more clearly in
Radially inwardly from top surface 54 in cover 50 are multiple surfaces that are generally inwardly facing. An innermost, mostly inwardly facing surface 60 is provided adjacent an inward edge 62 of cover 50. An intermediate surface 64 adjoins innermost surface 60 with top surface 54. Intermediate surface 64 is inwardly and upwardly facing.
Orifices 52 are provided only in the upwardly facing top surface 54 and generally inwardly facing surfaces 60 and 64. Orifices 52 are not provided in generally outwardly facing surfaces 56 and 58. Thus, flames 66 (
As seen most clearly in the cross-sectional view of
As shown most clearly in
For efficient combustion, the present invention provides control of secondary airflow in both volume and direction. The flow of air through the center opening of annular burner heads 22 and 24 is controlled by a restrictor plate 90 disposed within the center opening. Restrictor plates 90 have lateral tabs 92 secured to feet 94 of bases 34 and 38, to provide a substantially annular gap 96 between restrictor plate 90 and burner head base 38 and/or cover 50. Three tabs 92 are shown in the drawings, but fewer or more can be used. Attachment can be by screw, bolts or other suitable means. Further control of secondary airflow is provided through a central aperture 98 in restrictor plate 90. A slot 100 is provided in restrictor plate 90, to hold a pilot burner (not shown) of a pilot light system for igniting fuel at burner heads 22, 24.
Through selection of the size and shape of annular gap 96 and central aperture 98 for the size and performance of the burner, the proper amount of secondary air is allowed to enter and is properly directed for more efficient burner performance. Secondary combustion air flowing through annular gap 96 rises through burner head 22 or 24, near to and first encountering the lower originating flames from orifices 52 in innermost surface 60. The secondary combustion air provides complete, efficient combustion of gas emitted from orifices 52 in innermost surface 60. Remaining air from annular gap 96, and air rising through central aperture 98 disperses outwardly, providing secondary air for complete, efficient combustion of gas emitted from orifices 52 in intermediate surface 64 and in top surface 54. With flames directed upwardly and inwardly, air for secondary combustion is limited primarily to the air that flows upwardly through annular burner heads 22 and 24, and can be controlled by restrictor plate 90. This is in contrast to known burner designs with flames originating from orifices in outwardly facing surfaces that are exposed to virtually limitless and uncontrollable flow of ambient air.
It should be understood that the detailed structures described above for burner head 24, including a cover 50 and a restrictor plate 90, are provided in similar manner and construction for burner head 22.
The single casting 30 for both burner head 22 and burner head 24 having facilitates efficient disassembly and re-assembly for cleaning. Casting 30 can be removed with restrictor plates 90 fastened thereto, and with covers 50 remaining in place on burner head bases 34 and 38. Alternatively, covers 50 can be removed from burner head bases 34 and 38 before casting 30 is removed from cook top 14. Since covers 50 are self-centering and self-positioning on bases 34 and 38, removal and re-installation for cleaning are quick and easy.
Variations and modifications of the foregoing are within the scope of the present invention. It is understood that the invention disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present invention. The embodiments described herein explain the best modes known for practicing the invention and will enable others skilled in the art to utilize the invention. The claims are to be construed to include alternative embodiments to the extent permitted by the prior art.
Various features of the invention are set forth in the following claims.
