Displacement sensors for measuring the position in the non-contact type by a plurality of magnetic field sensors arranged in series

摘要

The present invention relates to a displacement sensor for contactlessly measuring a position of a magnet relative to a reference point. The displacement sensor comprises the magnet which can be displaced along a movement axis, a plurality of magnetic field sensors which are arranged in series and which are arranged parallel with the movement axis of the magnet and a calculation unit for forming a position signal which indicates the position of the magnet relative to the reference point. The plurality of magnetic field sensors which are arranged in series are arranged in such a manner that the displacement measurement ranges of adjacent magnetic field sensors overlap in an overlap range. The calculation unit is constructed in such a manner that, if the position of the magnet is contained in an overlap range, it forms the position signal on the basis of output signals which are output by the magnetic field sensors whose displacement measurement ranges overlap in the overlap range; and, if the position of the magnet is not contained in an overlap range, it forms the position signal on the basis of the output signal which is output by the magnetic field sensor, in the displacement measurement range of which the magnet is located. The overlap range between two displacement measurement ranges of adjacent magnetic field sensors is selected in such a manner that the total error of the position signal formed by the calculation unit in that overlap range is smaller than a maximum tolerable error.