抄録
In this paper, the shaft response characteristics of a floating bush hydrostatic gas bearing with an external damping (fluid damper) are investigated. The damping coefficients of fluid damper are defined by the damper clearance and the fluid viscosity. Several kinds of silicone oil, each of which is of different viscosity, are used as the damper fluid. When an impact force acts on the rotor, the rotor response generally shows under-damping. When the damping coefficients of fluid damper increase, the rotor response shows a change from under-damping to over-damping vibrations. Therefore, using the fluid damper can shorten the settling time of the rotor to about 2 natural period (5ms) of fundamental vibrations. The respective settling times for the rotor and the floating bush are almost the same. The optimum damping coefficient of fluid damper is set around 1. of damping factor in the fixed bush - floating bush bearing system.
