Apparatus for sensing proximity of a moving target

摘要

An apparatus for sensing the proximity of a moving target is provided which includes a sensor for sensing a range of distances between a reference point and a moving target. The sensor preferably has a detector for detecting a distance signal representative of a range of distances between a reference point and a moving target and a maximum and minimum generator responsive to the detector for generating a maximum distance range DC voltage signal representative of a maximum distance range value between a reference point and a moving target and for generating a minimum distance range DC voltage signal representative of a minimum distance range value between a reference point and a moving target. The sensor also preferably includes a memory device responsive to the maximum distance range signal and the minimum distance range signal for storing the maximum and minimum distance range DC voltage signals during a predetermined time period, a range value generator responsive to the memory device for generating a range value signal having an amplitude representative of a range value between the maximum distance range value and the minimum distance range value, and an output signal generator responsive to the range value signal for generating an output signal when the amplitude of the range value signal exceeds a predetermined threshold.