Abstract: A method of processing a rotor of a motor enabling to keep smooth rotation. After the ring-shaped magnet 34 is attached at inner circumference face 31B of an opening portion 31A of a cap-shaped rotor main body through a yoke 33, a rotor shaft portion 31C formed at outside of the main body of the rotor 31 and an attaching hole 31D of a shaft 32 fixed at the main body of the rotor are worked standardizing inner circumference face of the magnet 34. This process can match accurately center line of the magnet 34 and rotation axis of the main body of the rotor so as to keep smooth rotation.

Abstract: A motor for rotating a magnetic disk, an optical disk, or a magneto-optical disk comprises an armature concentrically secured to a center shaft affixed to the base frame of a disk drive unit. A rotor frame is rotatably supported in a cantilever fashion on a free end of the center shaft by a pair of bearings. The rotor frame is cup-shaped with a depending cylindrical sidewall encircling the outer peripheral surface of the armature. The sidewall includes a disk support that projects outwardly from the sidewall. A permanent magnet secured inside the sidewall interacts with magnetic fields produced by the armature. The cantilever support makes it easier to bring armature leads through a hole in the mounting frame as a part of the manufacturing process.In an alternate embodiment, the center shaft is shortened so that the lower bearing on the shaft rests upon the frame. The cup-shaped rotor is mounted on the bearings with a hub having a depending cylindrical wall mounted on the lower bearing.

Abstract: A method and apparatus for reducing the rotational noise in dc motors with rotor magnets, comprising forming the rotor magnet so that its magnetic center plane is aligned with the geometric center plane of the stator core, thereby providing for a distribution of the air gap magnetic flux density about the magnetic center plane in an asymmetric manner and reducing the rotational noise of the motor without the need to reduce the axial dimensions of the magnet.

Abstract: A motor for rotating a magnetic disk comprises an armature concentrically secured to a center shaft affixed to a mounting frame. A rotor frame having a cylindrical side wall of uniform outside diameter is rotatably supported in a cantilever fashion on a free end of the center shaft by a pair of bearings encircling the outer peripheral surface of the armature and a magnetic disk support that projects from the side wall. A permanent magnet secured inside the side wall is disposed to interact with magnetic fields produced by the armature. The cantilever support makes it easier to bring armature leads through a hole in the mounting frame as a part of the manufacturing process.

Abstract: This invention relates to a rotary solenoid or similar electromagnetic rotating apparatus that is capable of smoothly rotating through an angular range of approximately 180 degrees, in both directions, without employing a return spring or other like means.

Abstract: A motor for rotating a magnetic disk, an optical disk, or a magneto-optical disk comprises an armature concentrically secured to a center shaft affixed to the base frame of a disk drive unit. A rotor frame is rotatably supported in a cantilever fashion on a free end of the center shaft by a pair of bearings. The rotor frame is cup-shaped with a depending cylindrical sidewall encircling the outer peripheral surface of the armature. The sidewall includes a disk support that projects outwardly from the sidewall. A permanent magnet secured inside the sidewall interacts with magnetic fields produced by the armature. The cantilever support makes it easier to bring armature leads through a hole in the mounting frame as a part of the manufacturing process.In an alternate embodiment, the center shaft is shortened so that the lower bearing on the shaft rests upon the frame. The cup-shaped rotor is mounted on the bearings with a hub having a depending cylindrical wall mounted on the lower bearing.