| 摘要 |
<p>PROBLEM TO BE SOLVED: To increase an output of a sensor by flowing plenty of magnetic flux into a magnetic induction element. SOLUTION: An encoder 14 has a pair of permanent magnets 16a and 16b. Both these permanent magnets 16a and 16b alternately arrange south pole and north pole to each circumferential surface along its circumferential direction. As for a sensor 21, the magnetic induction element 24 is held between starting edge parts of the first and second focusing magnetic elements 22 and 23. A tip part of these each focusing magnetic elements 22, 23 is opposed to the circumferential surface of the above each permanent magnet 16a, 16b. The magnetic pole to which the tip part of the first focusing magnetic element 22 is in position and the magnetic pole to which the tip part of the second focusing magnetic element 16b is in position, are reverse to each other.</p> |
