Combustion device

Claim 1

A combustion device comprising a burner housing, a nozzle received in said burner housing, said nozzle being adapted to receive fuel which, after passage through the nozzle, is mixed with a stream of combustion air so that a resulting fuel-air mixture can be ignited and burnt, said nozzle comprising an oblong, generally cylindrical nozzle body and a nozzle head integrally formed with the nozzle body, an annular channel surrounding the nozzle and through which combustion air can be conducted, said nozzle being provided with a fuel channel that extends along the nozzle body and a plurality of holes that debouch to the side of the nozzle body so as to communicate the fuel channel with the annular channel, said annular channel being provided with an annular cavity in an area adjacent the holes that debouch to the side of the nozzle body, said annular cavity defining a whirl cavity for the air-fuel mixture, said burner housing being provided with a burner head adjacent one end, the annular channel in an area adjacent the burner head including a generally conically narrowing part that narrows toward a free end of the burner head in the streaming direction, said whirl chamber following the conically narrowing part in the streaming direction, said whirl chamber having a cross-section in the streaming direction that includes a portion having a predetermined radius of curvature immediately followed by a generally conically narrowing cross-section and an outlet part, said nozzle head cooperating with the burner head for forming the outlet part.