Natural frequency cyclic measurement equipment, and natural frequency cyclic measuring method

摘要

P To provide a natural vibration period measuring device capable of measuring a natural vibration period highly precisely and its measuring method. PSOLUTION: An evaluation pulse generation circuit 27 supplies an evaluation pulse to drive the piezoelectric vibrators of a recording head 1. An oscilloscope 28 binarizes a counter electromotive-force signal from the residual vibration generated after supplying of the evaluation pulse. A controller 29 extracts the maximum value exhibiting two adjacent maximum voltages as first and second peak values from binarized data rows, extracts a same level data as a preceding level datum and a subsequent level datum from among the peak value and the laterally adjacent counter peaks with respect to the first and the second peak values, extract as a middle datum the middle point datum between the preceding level datum and the subsequent level datum and obtains as the natural vibration period the time interval between the middle datum corresponding to the first peak value and the middle datum corresponding to the second peak value. PCOPYRIGHT: (C)2007 and JPO& INPIT