JPS57101725A - Oscillation measuring device - Google Patents

Abstract

PURPOSE:To conduct high-accuracy measurements of an amplitude and a phase without calibration, by making a braking characteristic a shortage characteristic and improving a phase characteristic above a resonating point, and as for an amplitude characteristic, by restraining an excessive output in the neighborhood of the resonating point by a reverse frequency characteristic filter. CONSTITUTION:An integrating amplifier 4 makes an output of a displacement proportioning signal B by integrating and amplifying a speed proportioning signal A from an oscillation detector 2 having an amplitude characteristic of shortage braking. A phase discriminating circuit 6 takes out an oscillation phase angle signal C from the displacement proportioning signal B. A reverse characteristic filter 8 takes out a displacement amplitude signal D from the displacement proportioning signal B. The phase characteristic of the oscillation detector 2 becomes as depicted in the figure, and when oscillation characteristic of a phase angle is measured within a range above a resonating point of d=1, phase deviation of the signal B becomes small, and the signal C can be easily taken out through the phase discriminating circuit 6. The amplitude characteristic is to become as E, and the output signal B of the integrating amplifier 4 is to have the similar characteristic, and by setting a reverse characteristic filter 8 as described hereunder, the signal D to be finally obtained is to have an overall characteristics as G.