Low-Noise Leaf Blower with Low-Emission Stratified Engine

The increasing use of gasoline-operated leaf blowers in residential areas calls for quieter but still powerful blowers. To respond to this need, a systematic acoustical development for a low-noise hand-held blower was performed. Based on a partial source analysis of the predecessor model, ambitious new partial sound targets were defined for each subassembly unit. Each partial sound target was addressed separately. The low-emission stratified engine as the power source was modified accordingly to fulfil the additional acoustical requirements for the low-noise blower. Without compromising blowing power, a sound level reduction of 8 dB(A) was achieved, such that the Category I limit is met, which is the best U.S. sound classification category.