Patent ID: 6104185
Filing Date: 2000-08-15
Classification: G01P

Abstract:
A method for operating a position sensor having a first part and a second part, one of the first part and the second part being movable in relation to the other one of the first part and the second part, the first part having a first section magnetized in a first direction and a second section magnetized in a second direction that is different from the first direction, and the second part having at least one magnetic field sensor, the method comprising the steps of:detecting a magnetic field of the first part with the at least one magnetic field sensor;converting the detected magnetic field into a signal having two levels depending on a polarity of a component of the magnetic field in a predefined spatial direction;analyzing the signal to determine a relative position of the first part in relation to the second part;detecting and storing a first level of the signal prior to a disabling of the at least one magnetic field sensor when the first part is at a standstill in relation to the second part;subsequently detecting a second level of the signal and comparing the detected second level with the stored first level when the at least one magnetic field sensor is enabled; andrecognizing a valid level change if the detected second level is different from the stored first level.