Apparatus for detecting a magnetically conductive object and position measuring system for measuring the position of a guide rod and associated position measuring method

摘要

An apparatus for detecting a magnetically conductive object in a detection area has an electrical coil and at least one sensor element. The apparatus is intended to be as free of degradation processes as possible and thus requires little maintenance and is configured and set up with the highest possible degree of redundancy and measurement reliability. For this purpose, the coil is set up to form a magnetic field in the detection area and the sensor element is configured to detect a magnetic field with a field strength, the magnitude of which is greater than a predefined threshold value. The threshold value is set to be higher than the field strength present in the detection area when the magnetically conductive object is absent and lower than the field strength present therein when the object is present.