PURPOSE: To calculate the frequency component of a required rotation order in a short time by converting a rotation reference pulse signal obtained from a rotating device, which drives a body to be measured, to plural kinds of preliminarily determined magnification.
CONSTITUTION: An analog processing part 1 corrects the signal level of an inputted signal S(t) to be measured by a preliminarily inputted reference signal level to send the signal level to a tracking low pass filter 2 and sends the signal S(t) to an A/D converter 3. The converter 3 outputs the inputted overall signal to a data bus 4. A rotation pulse signal T inputted to the processing part 1 is converted to a rotation reference pulse signal TA and is inputted to a frequency converter 5. The converter 5 sends a tuning signal TC to a filter 2 and sends a sampling clock signal SC to an A/D converter 6. The inputted signal TA is converted to RPM representation and is sent to a rotation number display part 7, and sample data of this rotation RPM signal and the signal S(t) converted to a digital value by the converter 6 are subjected to Fourier transform by a Fourier operating part 8.
SATO KAZUYUKI
FUTAGAMI TAKAO
| JPS57173353A | 1982-10-25 |
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