動力機械產生的聲音大小可以其聲功率位準(sound power level)來表示,聲功率位準越大,聲音可以傳得越遠,在與機械相同距離下的聲壓位準(sound pressure level)就越大。聲功率量測上,很多國家採用ISO的規範,本研究旨在整理動力機械的聲功率量測方法,建立標準量測程序。 在真實量測時,實際音源的位置無法如點音源般擺放在指定位置(如量測中心),必然會有所偏差,本文探討以ISO 3744、ISO 3746、ISO 6393方法量測時待測物音源有偏移時,對量測到的聲功率位準之影響,並比對理論值和實際值的差別。 最後本研究對實際動力機械進行量測,以作為建立國內動力機械,包括營建工程機具的聲功率量測標準方法之參考。
The sound level of power machines can be indicated by sound power. The higher sound power level can propagate far distance, and higher sound pressure level. During the measurement, the position of sound source can’t locate in the specified point, e.g. the measurement center, there is surely a little displacement, this paper discussed the effects of the wrong position of sound source on the measurement according to ISO 3744、ISO 3746、ISO 6393. The results of theoretical and practical measurements were compared. Finally, the measurement of sound power, e.g. the air compressor and the earth removing machines were performed, we hope the standard measurement method of sound power for power machines which are including construction machines would be established.