Patent ID: 7474026

Claim:
An electromagnetic drive device comprising: a stator; and a movable member supported in an inner peripheral side of the stator, the movable member being movable due to magnetic adsorbing force generated between the stator and the movable member, at least one of the stator and the movable member comprising: a magnetic body made of a magnetic material, the magnetic body including an uneven wall portion provided opposite to the other one of the stator and the movable member to have concavity and convexity, and a micro concave and convex portion formed on a surface layer of the concavity and convexity of the uneven wall portion, a clearance between any adjacent convex portions of the micro concave and convex portion being smaller than a clearance between adjacent convex portions of the concavity and convexity of the uneven wall portion; and a lubricating layer portion for covering an outer peripheral side of the magnetic body, the lubricating layer portion including lubricating particles and a carrier portion for retaining the lubricating particles, wherein the lubricating particle has an outer diameter, which is larger than the clearance between the adjacent convex portions of the micro concave and convex portion and is smaller than the clearance between the adjacent convex portions of the uneven wall portion.