Burner tube and venturi for gas grill
The present inventions provide, among other things, tapered burner tubes having raised gas ports and a smooth interior surface free from obstructions. Venturi members creating a smooth flow of the gas/air mixture along the top of the burner tube are also provided.
1. A venturi member for use in a burner tube for a gas grill, the burner tube having a length, a top with gas ports and a bottom, the venturi member comprising:
a front face having a top and a bottom, the front face including an opening to accommodate a neck of a gas valve;
a top flange extending rearwardly from the top of the front face and a substantially parallel bottom flange extending rearwardly from the bottom of the front face;
a downwardly sloping top constricting flange extending rearwardly from the top flange and an upwardly sloping bottom constricting flange extending rearwardly from the bottom flange, the top constricting flange and bottom constricting flange converging to form a throat area;
an upper arcuate portion extending rearwardly from the top constricting flange; and
a lower arcuate portion extending rearwardly from the bottom constricting flange, wherein the lower arcuate portion has a concave portion and a convex portion generally adjacent to the bottom of the burner tube.
2. The venturi member of claim 1 wherein the lower arcuate portion has a concave portion and a convex portion generally adjacent to the bottom of the burner tube.
3. The venturi member of claim 1 wherein a first turbulence area is created in the concave portion of the lower arcuate portion and a second turbulence area is created adjacent to the end of the convex portion of the lower arcuate portion.
4. The venturi member of claim 2 wherein the upper arcuate portion occupies the space where turbulence may form at the top of the burner tube adjacent to the gas ports and a first turbulence area is created in the concave portion of the lower arcuate portion and a second turbulence area is created adjacent to the end of the convex portion of the lower arcuate portion.
5. A burner for use in a gas grill, comprising:
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 and an upper surface, the upper surface including a plurality of gas ports having a height projecting above the upper surface 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, the venturi member including:
a front face having a top and a bottom, the front face including an opening to accommodate a neck of a gas valve;
a top flange extending rearwardly from the top of the front face and a substantially parallel bottom flange extending rearwardly from the bottom of the front face;
a downwardly sloping top constricting flange extending rearwardly from the top flange and an upwardly sloping bottom constricting flange extending rearwardly from the bottom flange, the top constricting flange and bottom constricting flange converging to form a throat area;
an upper arcuate portion extending rearwardly from the top constricting flange wherein the upper arcuate portion has a concave shape generally adjacent to the top of the burner tube; and,
a lower arcuate portion extending rearwardly from the bottom constricting flange wherein the lower arcuate portion has a concave portion and a convex portion generally adjacent to the bottom of the burner tube.
6. The burner of claim 5 wherein the upper arcuate portion occupies the space where turbulence may form at the top of the burner tube adjacent to the gas ports and a first turbulence area is created in the concave portion of the lower arcuate portion and a second turbulence area is created adjacent to the end of the convex portion of the lower arcuate portion.
7. The burner of claim 6 wherein the gas port height is between approximately 0.020 and 0.062 inches and the gas port opening diameter is between approximately 0.075 and 0.110 inches.
8. The burner assembly of claim 7 wherein the gas port height is approximately 0.060 inches and the port diameter is approximately 0.093 to 0.99 inches.
9. The burner assembly of claim 6 wherein a ratio of gas port height to gas port opening diameter is between approximately 0.640 and 0.650.
10. The burner assembly of claim 9 wherein the gas port height to gas port opening diameter ratio is greater than 0.5.
11. The burner assembly of claim 6 wherein the height of the gas ports is between 0.020 and 0.062 inches and the area of the gas port opening is between 0.006 and 0.008 square inches.
12. The burner assembly of claim 6 wherein the height of the gas port is approximately 0.060 inches and the area of the gas port opening is approximately 0.007 square inches.
13. The burner assembly of claim 5 wherein an air shutter is provided that cooperates with the open end of the burner tube to permit adjustment of the fuel and air mixture going into the burner tube.
14. The burner assembly of claim 6 wherein the port opening generally circular, having a diameter.
15. The burner assembly of claim 14 wherein the height of the gas ports is between 0.020 and 0.062 inches and the diameter of the opening is between 0.075 and 0.110 inches.
16. The burner assembly of claim 15 wherein the height of the gas ports is approximately 0.060 inches and the diameter of the opening is approximately 0.098 inches.