Step motor with position sensor

摘要

The stepping motor has an encoding disc (9) rotating on the motor shaft between a light source and photodetector , and has e.g. a 2-deg. graduation (T) giving a max. of 180 alternately transparent and opaque (11,12) arranged in an aperiodic sequence. Each sector may cover either one, two or three graduations while remaining sufficiently broad for unambiguous detection by a simple photodetector which accordingly emits a binary signal with run-lengths of not more than three ZERO or ONE bits.