Studies on the Sound and Vibration of a Gearbox. 3rd Report. Vibration Transmission and Sound Radiation.

An investigation of sound generated from a two-step reduction gearbox was carried out in order to obtain basic information for the reduction of sound. Test gears having an accuracy of Class JIS 1 were prepared, and the gearbox was driven with and without load. The experiments were carried out by the following three processes. In the first, the vibration transmission from the bearing housing to the top plane of the gearbox was examined. Second, the vibration and sound at nine positions on the top plane were measured simultaneously, and the radiation ratio at the positions were determined. Third, the distance characteristics of the sound at each position on the top plane were examined. From the experimental results and considerations, the vibration transmission and sound radiation of a gearbox were clarified, and some basic information for reduction of sound generated from a gearbox was obtained.