FIELD OF THE INVENTION

The present inventions relate to burners for use in gas appliances such as gas grills. More particularly, the present inventions relate to tapered burner tubes having raised gas ports and a smooth interior surface.

BACKGROUND OF THE INVENTION

Burners and burner tube assemblies, including those used in gas grills, are well known. Most conventional gas grills include burner tube assemblies that provide a plurality of burner tubes, gas valves and a gas distribution manifold. Each burner tube has a length defined by an open end and a closed end and a plurality of outlet ports along the length of the burner tube between the open and closed ends. The open end of the burner tube typically includes an air shutter that it used to adjust the gas and combustion air mixture, as well as a venturi region to increase the velocity of the gas/air mixture in the tube. The open end is connected to the neck of a gas control valve, which is in fluid communication with a gas distribution manifold, which is in fluid communication with a gas source such as a tank.

For cost, manufacturing and other reasons, many conventional burner tubes are constructed from hollow welded circular tubing, often made from stainless steel. A venturi region is typically formed by pinching the tube near the open end of the burner tube. The venturi increases the velocity of the fuel/air mixture from the gas nozzle into the burner tube. An air shutter is also typically provided on the open end of the burner tube to adjust the fuel to air mixture.

Also for cost and other manufacturing reasons, the gas ports of typical burner tubes are punched into the tube from the outside of the tube to the inside, either on the top or sides of the tube. This results in burrs or other obstructions on the inside of the burner tube that can disrupt the flow of the fuel/air mixture and provide poor flame quality. Moreover, the flames produced by those burner tubes typically sit directly on the surface of the burner tube itself. This increases the temperature of the burner tube and can result in increased corrosion and clogging of the ports as well as a shorter life of the burner tube. In addition, many known burner tubes have a substantially uniform cross-section along their length that can result in uneven or inconsistent fuel pressure along the length of the tube. This can also negatively affect flame quality.

Thus, there is a need for improved burner tubes that provide improved flame characteristics and quality and which increase the life of the burner tube. There is also a need for burner tubes that enable smooth fuel/air flow throughout their length, as well as consistent pressure throughout the length of the burner tube. The present inventions solve the above described and other deficiencies and provide new features and advantages over known burner tubes.

SUMMARY OF THE INVENTION

In general, the burner tubes of the present inventions are part of burner assemblies used with gas grills. The present inventions preserve the advantages of known burner tubes and provide new features and advantages, some of which are described below and others which will be apparent to those of ordinary skill in the art.

In accordance with the present inventions, a burner for use in a gas grill is provided. It includes a tapered burner tube having an open end, a closed end and a substantially hollow and smooth interior which is free of burrs or other obstructions. The burner tube includes an upper surface, the upper surface including a plurality of gas ports having a height projecting above the upper surface of the tube and an opening at the top of the height, the opening having a diameter. A venturi member at the open end of the burner tube is also provided, the venturi member including two opposing, generally v-shaped flanges to restrict the interior of the open end of the burner tube.

In a preferred embodiment, the gas port height is between approximately 0.020 and 0.62 inches and the opening diameter is between approximately 0.075 and 0.110 inches. More specifically and preferred, the gas port height is approximately 0.060 inches and the port diameter is approximately 0.093 inches. In addition and as preferred, the ratio of gas port height to opening diameter is between approximately 0.640 and 0.650, and preferably greater than 0.5.

The present inventions also provide a burner assembly for a gas grill, the assembly having a burner tube, the burner tube including an open end and a closed end and a length between the open end and the closed end and an upper surface. The burner tube further includes a cross-sectional shape defining a hollow interior, wherein the cross-sectional shape is tapered and defines an area that decreases from the open end to the closed end. Also included is a plurality of raised gas ports along the length of the upper surface of the burner tube, the gas ports having a height projecting above the upper surface of the burner tube and an opening at the top of the height of the gas port, the opening having a diameter. In addition, the hollow interior of the burner tube is free from burrs or other obstructions.

In a preferred embodiment the ratio of the height of the gas port in inches to the diameter of the gas port opening in inches is between approximately 0.625 and 0.670. It is also preferred that the height of the port is between 0.020 inches and 0.062 inches and the opening diameter is between 0.075 inches and 0.110 inches. More specifically and preferred, the height of the port is approximately 0.060 inches and the opening diameter is approximately 0.093 inches.

Also provided by the present inventions is a burner assembly for a gas grill, the grill having a fuel source, a gas distribution manifold in fluid communication with the fuel source and control valves in fluid communication with the gas distribution manifold. A burner tube having an open end, a closed end and a substantially hollow interior, the burner tube gradually tapering from the open end to the closed end, is also provided. A plurality of raised gas ports Is included on an upper surface of the burner tube, the gas ports projecting above the upper surface of the burner tube having a height front the upper surface and an opening at the top of the height, the opening having an area. The interior of the burner tube is free from burrs or obstructions to permit the smooth flow of fluid along the length of the interior of the burner tube and wherein a flame sits on top of the openings of the gas ports and above the upper surface of the burner tube.

In a preferred embodiment, the height of the gas ports is between 0.020 and 0.062 inches and the area of the port opening is between 0.006 and 0.008 square inches. In the particular preferred embodiment, the height of the gas port is approximately 0.060 inches and the area of the opening is approximately 0.007 square inches. A venturi member and an air shutter may also be provided.

Alternatively, the port opening may be generally circular and have a diameter. In a preferred embodiment, the height of the gas port is between 0.020 and 0.062 inches and the diameter of the opening is between 0.075 and 0.110 inches. In the preferred embodiment, the height of the gas port is approximately 0.060 inches and the diameter of the opening is approximately 0.093 inches.

Accordingly, it is an object of the present inventions to provide a safe, reliable burner tube that efficiently operates over a wide range of gases and mixtures and a wide range of input pressures.

It is another object of the present inventions to provide a tapered burner tube that enables consistent pressure along the length of the tube.

Still another object of the present inventions is to provide a burner tube having a smooth interior surface that enables laminar fluid flow along the length of the interior of the tube.

Yet another object of the present inventions is to provide raised gas ports that enable better flame characteristics and help maintain a cooler burner tube temperature.

Still yet another object of the present inventions is to manufacture the burner tube by forming the raised gas ports from what will be the inside of the burner tube to what will be the outside of the burner tube so that the interior of the burner tube is smooth and tree from burrs of other obstructions.

An additional object of the present inventions is to reduce corrosion and gas port clogging of the burner tube.

Still an additional object of the present inventions is to provide larger gas port openings that provide improved flame characteristics and are less susceptible to corrosion, yet are not prone to backflash or flame pull back into the burner tube when in use.

Yet an additional objection of the present inventions is to enable greater material selection as well as manufacturing and cost advantages.

A further object of the present inventions is to provide a burner tube having improved flame characteristics and less material degradation.

Still a further object of the present inventions is to provide an improved venturi member and including one that functions with a burner tube having a non-circular cross-section.

Still yet another object of the present inventions is to provide an improved burner tube having a tapered cross-section, a venturi member and an air shutter that cooperates with the open end of the burner tube to adjust the fuel/air mixture.

Inventor'S Definition of the Terms

The following terms which may be used in the various claims and/or specification of this patent are intended to have their broadest meaning consistent with the requirements of law:

As used herein, “front” or “forward” is used by reference to the front or toward the front of a gas grill which typically includes the control panel, gas control knobs and the like.

As used herein, “rear” or “rearward” is used by reference to the back or toward the back of a typical gas grill.

As used herein, “air shutter” shall mean the device, typically found at the open end of the burner tube, that cooperates with the open end of the burner tube to permit the adjustment of an opening of the burner tube to control the fuel to combustion air mixture.

As used herein, “ignition system” shall mean devices that are capable of generating sparks to ignite the fuel/air mixture emitted from the outlet ports of a burner tube.

Where alternative meanings are possible, in either Ute specification or claims, the broadest meaning is intended consistent with the understanding of those of ordinary skill in the art. All words used in the claims are intended to be used in the normal, customary usage of grammar, the trade and the English language.

