Apparatus for producing square shaped pulses from a generally sinusoidally shaped signal

摘要

Apparatus is disclosed for generating electrical pulses in response to rotation of a shaft. The apparatus incorporates an internal optical disc carried by a hub assembly attached to the operating shaft, with the hub assembly having a beveled bearing surface at one end thereof for engaging a similarly beveled surface of the apparatus housing, and biasing means for biasing the hub assembly toward said housing beveled surface to compensate for mechanical wear and to also minimize erratic movement of the optical disc. The combination of a light emitting diode and photo-transistor generate electrical signals in response to the blocking and transmitting of light through radially oriented opaque segments of the disc during rotation. The light emitting diodes and photo-transistors are retained by receptacles which snap fit within cooperating apertures of the housing. A second combination of a light emitting diode and photo-transistor, together with a second stationary disc provide two phase shifted signals which can reduce problems caused by jitter, backlash and the like.