| 摘要 |
PURPOSE:To measure the gap between the driving member and driven member of an actuator. CONSTITUTION:A driving member 2 is constituted of a yoke 3, platy permanent magnet 4, and annular coil 5 by forming a recessed section 3b on the central part of the lower surface of a cylindrical yoke 3 and a groove section 3c around the section 3b and respectively putting the magnet 4 and coil 5 in the sections 3b and 3c. Holes 3a and 4a are respectively bored at the central parts of the yoke 3 and magnet 4 so as to form a funnel-shaped through cavity section 7 from the upper surface to the lower surface of the member 2 of the holes 3a and 4a. A driven member 12 composed of a magnetic material is counterposed to the bottom of the member 2 with a prescribed gap A in between. Therefore, the distance to the upper surface of the driven member 12 can be measured through the cavity section 7 and the gap A between the members 2 and 12 can be indirectly found from the distance. |
