Rotary speed detector

Abstract

Abstract PURPOSE:To relieve phase lag, by constituting an operating means, a lagging means and a multiplying means such that they have differentiating characteristics. CONSTITUTION:Optical sensors 202, 203 in a pulse generating means 2 output pulse trains having 90 deg.C shifted phases as a motor rotates. A pulse generating means 3 outputs a pulse every time when respective pulses arrive. A period measuring means 4 measures the period of four proceeding pulses every time when an output pulse from the pulse generating means 3 arrives and provides the period to a latch means 5. A pulse generating means 7 provides a pulse to a lagging means 8 for every rising and falling of an output pulse from the optical sensor 203. The lagging means 8 delays an input pulse by a predetermined time and provides the delayed pulse to a means 9 for multiplying a predetermined value smaller than 1. An operating means 6 subtracts the output of the multiplying means 9 from the output of the latch means 5 and provides the result as a rotary speed signal.

Inventors

• 👤 Soichiro Fujioka
• 👤 Hiroshi Okamoto

Bibliographic Details