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 sealing structure for use in efficiently and effectively preventing the egress of grease aerosol particles from a motor. The seal comprises forming a high speed air flow at an outer end of a bearing assembly of the motor, which air flow will not permit the passage of such aerosol particles outside the bearing assembly.

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: A slotless, brushless DC motor having thin, flat coils fixed to the inner surface of a thin insulating cover attached to the cylindrical inner surface of the stator core of the motor. The coil ends are bent and fixed to the insulating cover over the end faces of the stator core. The structure provides a reduced air gap increasing the rotor efficiency and a reduced axial length of the motor. The coils are arranged such that adjacent coils sides are in contact with each other and may be connected in a Y-configuration or a .DELTA.-configuration.

Abstract: An oscillating motor capable of 180.degree. displacement and return without return springs.

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.