A cooking appliance is provided, including a cooktop floor and a removable cooking vessel support system on the cooktop floor. The cooking vessel support system includes a support frame configured to support a cooking vessel above a gas burner, the support frame having at least a first arm supporting the gas burner above and spaced apart from the cooktop floor. The support frame includes an internal passageway in fluid communication with the gas burner and configured to draw primary air into the support frame at a location above the cooktop floor and to mix the primary air with an injected gas to provide an air-gas mixture. At least a portion of the internal passageway is formed in the first arm of the support frame such that the air-gas mixture is guided by the internal passageway through the first arm to the gas burner.

The invention relates to a burner installable to a boiler for burning a premixed air-fuel mixture, said burner comprising a frame member provided with an elongated combustion head protruding from the frame member and having what in a view from the frame member is its distal end provided with a tip plate. In said burner between a side edge of the tip plate and the plane of the tip plate is an oblique angle of incidence for directing a gas delivered forward of the tip plate away from the longitudinal center axis of the combustion head, the combustion head has its tip plate provided with a plurality of air openings extending through the tip plate and it is for cooling the tip plate that the inner tube is additionally provided with a supply of combustion air for conveying the combustion air through the tip plate's air openings.

A gas cooking assembly comprises: (a) a base part (10) comprising: (a1) a burner body (14) for installation in a cooktop surface (16); (a2) a gas outlet (20) in the burner body (14); and (a3) an ignition source (22) in the burner body (14); and (b) an upper part (12) comprising: (b1) at least one foot (36) for supporting the upper part (12) on the cooktop surface (16); (b2) a grate (26) for supporting a cooking vessel; (b3) an annular flame spreader (28); and (b4) a gas inlet (46) at the bottom side of the flame spreader (28); wherein the upper part (12) is an integral unit that is removable from the base part (10), wherein when the upper part (12) is connected to the base part (10), the gas inlet (46) of the upper part (12) connects to the gas outlet (20) of the base part (10).

A cooking appliance is provided, including a cooktop floor and a removable cooking vessel support system on the cooktop floor. The cooking vessel support system includes a support frame configured to support a cooking vessel above a gas burner, the support frame having at least a first arm supporting the gas burner above and spaced apart from the cooktop floor. The support frame includes an internal passageway in fluid communication with the gas burner and configured to draw primary air into the support frame at a location above the cooktop floor and to mix the primary air with an injected gas to provide an air-gas mixture. At least a portion of the internal passageway is formed in the first arm of the support frame such that the air-gas mixture is guided by the internal passageway through the first arm to the gas burner.

A premixing device includes a first and a second venturi in which air flows by rotation of a centrifugal fan, first and second communication openings disposed in the venturis, respectively, for allowing fuel gas supplied from a gas supply passage to flow out, a flap valve capable of opening and closing the second venturi on a side downstream of the second communication opening, and an equalizing valve disposed in the gas supply passage on a side upstream of the first and the second communication openings. The gas supply passage, which connects between an outlet of the equalizing valve and the first and the second communication openings, diverges from the outlet of the equalizing valve to independently form a first gas passage and a first straight path, and a second gas passage and a second straight path for the venturis, respectively.

An apparatus includes first and second mixer tubes. The first mixer tube contains a first gas flow passage having an inlet communicating with the source of fuel gas and an outlet to a combustion chamber. The second mixer tube contains a second gas flow passage having an inlet communicating with the source of combustion air and an outlet to the combustion chamber. The apparatus further includes premix control means for forming fuel gas-combustion air premix in the second passage by directing fuel gas from the first passage into the second passage, and for alternatively forming fuel gas-combustion air premix in the first passage by directing combustion air from the second passage into the first passage.

The invention relates to a burner installable to a boiler for burning a premixed air-fuel mixture, said burner comprising a frame member provided with an elongated combustion head protruding from the frame member and having what in a view from the frame member is its distal end provided with a tip plate. In said burner between a side edge of the tip plate and the plane of the tip plate is an oblique angle of incidence for directing a gas delivered forward of the tip plate away from the longitudinal center axis of the combustion head, the combustion head has its tip plate provided with a plurality of air openings extending through the tip plate and it is for cooling the tip plate that the inner tube is additionally provided with a supply of combustion air for conveying the combustion air through the tip plate's air openings.

A combustion system for a coal fired furnace having a windbox includes a source of a mixture of pulverized coal and air, and a splitter that receives the mixture and splits it into first and second mixed streams. A first nozzle receives the first mixed stream and discharges it into the furnace. A separator receives the second mixed stream and separates it into an air stream and a coal rich stream. An air conduit connected between the separator and the source of the mixture causes at least some of the air stream to be fed back into the mixture. A second nozzle receives the coal rich stream and discharges it into the furnace. A third nozzle receives support air from the windbox and discharges it into the furnace in a combustion supporting relationship with respect to the coal rich stream.

A pre-mix burner apparatus includes a burner having a generally cylindrical burner surface, the burner having a generally circular burner inlet at one end of the burner, the burner inlet having an inlet diameter. A flow distribution member is arranged to distribute flow of fuel and air mixture into the burner. The flow distribution member includes a closed axially central portion configured to block flow of fuel and air mixture axially centrally into the burner. The flow distribution member includes a plurality of vanes extending radially outward from the closed axially central portion. The vanes are configured to generate a swirling flow of fuel and air mixture flowing past the vanes into the burner.

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.