PURPOSE: To suppress vibration caused by a ball bearing when the rotor of a motor rotates at high speed by fixing at least one ball bearing to the stator of a motor through a vibration absorbing member.

CONSTITUTION: Bearing housing 18 on the fixed side is provided with a planar motor base part 18c and a tubular part 18b projecting from the central part thereof, and a substantially tubular vibration absorbing member 25 is secured in the hollow part 18a of the tubular part 18b. A step part is formed in the hollow part of the vibration absorbing member 25 and a pair of ball bearings 19, 20 are arranged coaxially such that the vibration absorbing member 25 abuts partially on the outer peripheral faces and one end faces of the outer rings 19b, 20b thereof. Consequently, the vibration caused by the ball bearings 19, 20 is absorbed and damped by the vibration absorbing member 25 during rotation of a rotor 7. This structure damps vibration caused by the ball bearings at the time of high speed rotation of the rotor of motor.