SERVO-TYPE ACCELEROMETER AND ACCELERATION MEASURING INSTRUMENT

PROBLEM TO BE SOLVED: To correctly measure infinitesimal vibration acceleration under the condition that acceleration of gravity of the earth constantly works. SOLUTION: A servo-type accelerometer includes a displacement detecting part for generating an electric signal corresponding to displacement in position of a mass body with respect to a housing, an amplifier for amplifying the electric signal, a low pass filter for taking out a DC signal component from an output of the amplifier to generate a first feedback current, a high pass filter for taking out an AC signal component with a predetermined or higher frequency from the output of the amplifier to generate a second feedback current, and a first torquer coil and a second torquer coil for restoring the mass body to a neutral position by electromagnetic force caused by the first feedback current and the second feedback current respectively supplied. Since the second feedback current containing the AC signal component corresponding to the infinitesimal vibration acceleration is generated, a resistance value of a second reading resistor can be increased, thereby correctly measuring the infinitesimal vibration acceleration. COPYRIGHT: (C)2010,JPO&INPIT