| 摘要 |
PROBLEM TO BE SOLVED: To provide a combustion device capable of satisfactorily reducing noise when operating a centrifugal fan such as a sirocco fan used for supplying combustion air. ! SOLUTION: A centrifugal fan F1 for supplying combustion air to the inside of a burner case of a combustion device has a configuration in which, in the case where a perpendicular Lb is drawn from a boundary part 66 between a tongue part 61 of a fan case 6 and a first side wall part 62a continuing to the tongue part 61 to a reference line La for connecting a spiral ending part 60b and a spiral center O of the fan case 6, each blade 40 of an impeller 4 does not further protrude to the spiral ending part 60b side than the perpendicular Lb. ! COPYRIGHT: (C)2015,JPO&INPIT |
