| 摘要 |
<p>PURPOSE:To eliminate misdetection due to dust, etc., and to detect an initial position by arranging a sensor consisting of magneto-resistance elements opposite a magnet ring which is narrowed down in magnetic pole pitch partially and converting variation of a magnetic field into a pulse signal. CONSTITUTION:The magnet ring 5 which is reduced in the pitch of magnetic poles partially is locked to the steering wheel, etc., of a vehicle through a specific cam and the sensor 16 which consists of the magneto-resistance elements 13 and 13a and pulse generating circuits 14 and 14a and is not affected by dirt and a lubricant is arranged opposite the magnet ring. The elements 13 and 13a detect passage in the magnetic field by the rotary movement of the ring 5 associated with the operation of the steering wheel to caused voltage variation, which is converted by the circuits 14 and 14a into the pulse signal; and the pulse signal is sent to a microcomputer, etc., to detect the angle of rotation from the number of pulses and the rotating speed from a pulse position difference. Consequently, the misdetection caused by the dirt and lubricant is eliminated and the initial position is detected by the magnetic poles with narrow pitch width.</p> |
