VERFAHREN ZUR MESSWERTERMITTLUNG BEI INKREMENTALEN WEG- UND WINKELMESSYSTEMEN

摘要

The method of obtaining an accurate interpretation of the phase encoded output signals of a photoelectric, capacitive or inductive linear or angular displacement measurement transducer, uses a coarse pitch counter network which operates in parallel with a fine phase detection network. Two phase shifted, typically sinusoidal signals produced by the transducer concerned are fed to a coarse null point detector network (1) and also to a fine phase detection network (2). The coarse detector squares the incoming signals (3, 4) and uses the edges of these to produce an impulse chain which is counted (6) to give the coarse position. The fine phase detection network contains a phase evaluation circuit (7) which feeds pulses to another counter (8) in which the fine position is stored. A final evaluation network (10) combines the coarse and fine data to give the total accurately defined position.