| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a tachometer capable of obtaining a correct revolution speed even if a detection signal of a detection unit is missing. <P>SOLUTION: The tachometer having a plurality of detection bodies arranged with the same intervals on a circumference of a rotor and a main detection unit that is disposed in proximity to the detection bodies and detects their passing includes: a secondary detection unit that is disposed so as to be isolated with a prescribed angle from the arrangement position of the main detection unit in the circumference direction and detects the passing of the detection bodies; and a revolution speed calculation unit that inputs a detection signal from the main detection unit and a detection signal from the secondary detection unit and calculates the revolution speed of the rotor. <P>COPYRIGHT: (C)2012,JPO&INPIT |
