ROTATION DETECTION DEVICE

PROBLEM TO BE SOLVED: To accurately detect the rotation angle of a rotation axis such as a rotating shaft, in spite of being small in size. SOLUTION: This rotation detection device 10 is provided with a first and second timing rotors 12, 13 which rotate together with a rotating shaft 11, and a rotation detection sensor 14 which detects changes in magnetic fields caused by the rotation of the first and second timing rotors 12, 13, and thereby detects the rotating state of the rotating shaft 11. The first and second timing rotors 12, 13 are arranged close to each other, and a nonmagnetic spacer 15 for suppressing interference between the timing rotors 12, 13 interposes between them. The detection sensor 14 is provided with a first and second magnetic sensors (spin valve GMR circuits) 16a, 16b arranged at its tip, a bias magnet 17 which is provided at their back and generates a magnetic field around the magnetic sensors 16a, 16b, and a case 18 for holding these. COPYRIGHT: (C)2008,JPO&INPIT