| 摘要 |
<P>PROBLEM TO BE SOLVED: To accurately detect a revolution speed of a rotary member with a fixed encoder, even when an output signal of a rotation detecting sensor is varied by fluctuation in distances between a detected face of the encoder and a detecting part of the rotation detecting sensor. <P>SOLUTION: A sensor capable of transmitting an analog signal varied as shown by a full line c in (A) is used as the rotation detecting sensor. The analog signal is compared with threshold values shown by broken lines a, b in the (A), by a comparator, to obtain a digital data shown in (B). The threshold values are changed in response to a peak value just before the analog signal. By this constitution, a pitch of the digital signal is prevented from being shifted with respect to a pitch of the analog signal, irrespective of fluctuation of the analog signal based on the fluctuation in distances, so as to solve the problem hereinbefore. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
