Air Damper について

抄録

The resisting force by air damper is not exactly proportional to the velocity of the motion of seismometer, as already pointed out by Dr. T. Hagiwara. Hence the frequency response of the seismometer with air damper is different from that by the ordinary theory of seismometers. The author studied mathematically the motion of the seismometer in such a case, for both free and forced oscillations, and calculated the true frequency response curves. The numerical results of calculations for the seismometer of Ishimoto type (natural frequency; 50c/s, weight of mass; 15kg, sectional area of the damper; 50cm²) are shown in Figs. The difference between the true response curves in the present case and those by the ordinary theory are not always neglisible, especially when the damping coefficient is large.