| 摘要 |
<p>A position sensor (25) includes a position potentiometer (90) and a turns count potentiometer (92). The position potentiometer (90) includes a pair of wipers (12 and 14) positioned on a rotor (10) which contact a resistive track (46) and one of two different commutator tracks (48 and 50) on element (26). The voltage output corresponds to the angular position of the wiper (12 or 14) on the resistive track (46). The turns count potentiometer (92) comprises a turns count rotor (66) which is incrementally advanced via a cog (18) on rotor (10) using a gear or geneva type mechanism. The turns count rotor (66) includes a wiper (64) which either contacts both a resistive track (150) and commutator track (152) or contacts one of a plurality of switch pads (154). By determining the sensed voltage output from the turns count potentiometer (92) or identifying which switch pad (154) the wiper (64) has contacted, the number and direction of full revolutions of rotor (10) can be determined. The precise angular displacement is determined by adding the resulting angles obtained from the position potentiometer (90) and turns count potentiometer (92).</p> |
