Abstract
The elastic vibration of a railway carbody influences a riding quality, and vibration reduction is required. The first mode of the elastic vibration of the carbody can be reduced by using dynamic vibration absorber (DVA) effect utilizing bogie-carbody dynamic interaction proposed in the previous paper. On the other hand, vibration increases in high frequency range. In this paper, the damper having frequency dependent characteristic is proposed to reduce the elastic vibration of the carbody in high frequency range. It has high damping in low frequency range to get DVA effect, and low damping in high frequency range to obtain the isolation effect for input from the truck. A prototype damper having plastic valve as like an orifice is manufactured. The sectional area of the orifice is varied by velocity of the piston, and damping characteristic can be switched in high frequency range. In order to estimate the damping coefficient, vibration test is carried out. Finally, dynamic characteristic of the damper is investigated experimentally.
