Patent ID: 7615993
Filing Date: 2009-11-10
Classification: G01D,G01R

Abstract:
1. A magnetic line-type position-angle detecting device comprising: a magnetic line sensor having a plurality of magnetic sensor elements arranged in a linear array; a magnetic generating element held in face-to-face relation with the magnetic line sensor and movable along the magnetic line sensor in a direction conforming to the direction in which the magnetic sensor elements are deployed; a scanning circuit to sequentially select one of the magnetic sensor elements of the magnetic line sensor; an amplifier to amplify a signal outputted from the selected sensor element; an analog-to-digital converting circuit to convert an output from the amplifier into a digital signal; and a calculation processing circuit to evaluate a distribution of magnetic fields, applied to the magnetic line sensor, in reference to an output of the analog-to-digital converting circuit to thereby calculate a position and/or an angle of the magnetic generating element, wherein the calculation processing circuit is capable of detecting a zero-crossing position of a waveform of a sensor signal outputted from the analog-to-digital converting circuit, wherein the magnetic generating element has two magnetic pole boundaries in a direction in which the sensor elements of the magnetic line sensor are arranged, and wherein the calculation processing circuit is capable of detecting the position of the magnetic generating element by detecting two zero-crossing positions obtained from a waveform of the sensor signal outputted from the analog-to-digital converting circuit.