Patent ID: 9618368
Date: 2017-04-11
CPC Classifications: G01D

Claim:
1. A position-measuring device, comprising: a scale having an incremental measuring graduation and a plurality of reference marks spaced apart from each other in a measurement direction, a reference mark pulse being generatable by scanning one of the reference marks, the scale having a first marking track containing a first marking associated with one of the reference marks and a second marking spaced apart from the first marking in the measurement direction, the second marking being longer than the first marking in the measurement direction, a switching signal being generatable by scanning the second marking; and a scanning unit movable relative to the scale in the measurement direction, the scanning unit having, for purposes of scanning the first marking track, a first detector and a second detector spaced apart from the first detector in the measurement direction, a distance between the first detector and the second detector being greater than a length of the first marking and less than a length of the second marking, each of the detectors being configured to generate a scanning signal in response to scanning one of the markings, the scanning unit being configured to produce the reference pulse based on only the first detector of the two detectors generating a scanning signal, and to produce the switching signal when both the first detector and the second detector generate a scanning signal.