ROTARY DRIVE DEVICE

摘要

PURPOSE:To obtain a linear characteristic of a rotary drive device and to improve the durability of the device by disposing 2-pole rotary permanent magnet in the first magnetic path, and providing a ferromagnetic yoke as the second magnetic path in contact with the first path. CONSTITUTION:A coil 4 for generating a magnetic flux is wound on a yoke 1 made of ferromagnetic material to form a magnetic path MP-A. A through hole 11 is opened at the yoke 1 in a direction perpendicular to a yoke shaft, and a rotary permanent magnet 3 magnetized radially in 2 poles is disposed rotatably in noncontact with the yoke 1. A yoke 2 as the second yoke made of a ferromagnetic material is disposed in a direction perpendicular to the yoke shaft of the yoke 1 and the axis of the hole 11 to form a closed magnetic path MP-B in contact with the yoke 1.