Sound of Linear Guideway Type Recirculating Linear Ball Bearings

Abstract

The sound characteristics of linear guideway type (LGT) recirculating linear ball bearing driven at a constant linear velocity was studied. The measurement results of the sound characteristics showed that the LGT recirculating linear ball bearing has a sound property between line sound source and point sound source, and the measured overall sound pressure level increases with increasing the linear velocity of the carriage. The rate of increase of the overall sound pressure level to the linear velocity was analyzed combining the deduction of Yamada et al. and the results of previous studies on the collision sound. The results of this analysis match roughly the rate of increase of the measured overall sound pressure level to the linear velocity. We also observed the main peaks in the sound spectra of the LGT recirculating linear ball bearing itself. As a result, it was made clear that the main peaks are caused by the lower rolling natural vibration of the carriage, the pitching natural vibration of the carriage, and the vertical natural vibration of the carriage. In addition, the frequencies of the main peaks can be estimated by using presented expressions fRL, fP, and fv.