ROTATION DETECTOR

PROBLEM TO BE SOLVED: To provide a rotation detector having high setting accuracy on a distance between a magnetic sensing element for sensing a change in a magnetic field and a rotor, and making it easy to take restrictive measures or remedial measures on detection accuracy deterioration with respect to the rotation of a rotor owing to an error in distance between the sensing element and the rotor. SOLUTION: This rotation detector is equipped with the rotor 20 provided, as a detecting object on rotation, on a rotary shaft 21 which rotates while being supported by a housing 10 having a bearing, a semiconductor chip 30 having the magnetic sensing element for sensing a change in the magnetic field in the vicinity of the rotor 20, and a bias magnet 40 for giving a bias magnetic field to the sensing element. This detector is provided as a rotation detector for obtaining rotation information on the rotor by sensing a change in the magnetic field which arises in conjunction with the bias magnetic field when the rotor 20 rotates. In such a rotation detector, the bearing and the semiconductor chip 30 are formed integrally with the housing 10. COPYRIGHT: (C)2006,JPO&NCIPI