| 摘要 |
A debris blower with a radial flow fan having an impeller (18) that includes a set of impeller blades (104,106) that are spaced about a rotary axis of the impeller in a predetermined manner such that at least two spacing angles are used to space the impeller blades circumferentially apart from one another. The use of a plurality of spacing angles operates to distribute the noise that is generated by the rotating impeller blades over several tones or frequencies. <IMAGE> |
