Method for contactlessly measuring a relative position by means of a 3D hall sensor having measurement signal store

摘要

The present invention relates to a method for contactlessly measuring a relative position of a magnetic field source (102) which produces a magnetic field and a magnetic field sensor (100) in relation to each other. The present invention further also relates to a corresponding displacement sensor. The invention describes an operating principle of a sensor which is based on the Hall effect and which achieves an increase in the sensor output range with a magnet which is simultaneously reduced in size by storing the earlier value when control by the magnetic field is lost. In particular, the method comprises the steps of: calculating the position signal on the basis of a quotient of two magnetic flux density components; calculating a magnitude of the magnetic flux density and comparing the magnitude with a predetermined threshold value; outputting the current calculated position signal if the magnitude of the magnetic flux density is higher than the threshold value; outputting a preceding stored position signal if the magnitude of the magnetic flux density is smaller than or equal to the threshold value; storing the output position signal.

主权项

1. A method for contactlessly measuring a relative position of a magnetic field source which produces a magnetic field and a magnetic field sensor in relation to each other,
wherein the magnetic field source and the magnetic field sensor are movable relative to each other, wherein the magnetic field sensor detects at least two spatial components (By, Bz) of a magnetic flux density of the magnetic field and a position signal is produced from the measured components, and wherein the method comprises the following steps: calculating the position signal on the basis of a quotient of the two magnetic flux density components, calculating a magnitude of the magnetic flux density and comparing the magnitude with a predetermined threshold value, outputting the current calculated position signal if the magnitude of the magnetic flux density is higher than the threshold value, outputting a preceding stored position signal if the magnitude of the magnetic flux density is smaller than or equal to the threshold value, and storing the output position signal.