Abstract: A disk storage device that utilizes an inner rotor spindle motor in which the spindle shaft is fixed to the disk mounting hub and rotates therewith. Support for the spindle is provided by a bearing tube that has a greater diameter and greater rigidity than the stationary shaft or post typically employed to support the disk stack in an outer rotor arrangement. The bearing tube supports the bearings in which the spindle shaft is journalled and allows wider axial spacing between the bearings, reducing spindle run out. At the same time, the bearing tube functions to entrap contaminants from the bearings within the internal motor space and reduces contamination in the clean chamber. Further, the motor elements are located outside the clean room chamber, further enhancing the cleanliness of the environment surrounding the data storage disks.

Abstract: A compact disk storage device having outer-rotor electric motor for directly driving a disk for recording and reproducing information has an axially deep, tank-form flange and a stationary shaft, upon which the mounting annulus of the flange and the ball bearings of the hub are axially displaced. The hub includes a cover disk for sealing an extremity of the ball bearings and an inverted cup shape rotor providing magnetic shielding. The flange includes a mounting rim substantially aligned with the back surface of the cup-shape rotor. The facing cup-like and tank-form shapes readily enable labyrinth seals and substantial and abutting axial extents along the axis of the stationary shaft.

Abstract: The invention relates to a spindle driving motor, in particular an external rotor motor, the main components of which are accommodated in the interior of a driving hub (4) or the back iron (5). According to the invention, in order to minimize the number of joints, both ball bearings (11, 12) are arranged directly, yet correctly as far as assembly is concerned, between the fixed shaft (10) and the back iron (5), a collar (15) having a larger diameter serving in particular to this end.

Abstract: A disk storage has one or more disks provided with center holes. An electric motor extends coaxially through these holes and has an external rotor to the outer circumference of which the disks are secured so that they rotate with the rotor. A labyrinth seal is provided for at least reducing the escape of contaminants from the motor.

Abstract: A three-phase brushless dc motor includes a permanent-magnet rotor magnet arrangement having at least four poles and a Y-connected, or star-connected, three-phase stator winding. The winding's phases are arranged non-overlapping in slots of a slotted stator, the currents flowing in the three phases being controlled via at least three semiconductor elements by at least three magnetic-field-sensitive rotor position sensors. Each sensor is associated with a respective two of the winding's three phases and triggers a commutation which switches off the current in one of the associated two phases and switches on the current in the other of the associated two phases. The sensors are located to sense the permanent-magnet flux emanating from the rotor poles themselves. The rotor position sensors are provided at special angular locations on the stator.

Abstract: A disk storage drive is provided with a brushless drive motor having a stator with a winding. An external rotor coaxially surrounds the stator and is spaced therefrom by a substantially cylindrical air gap. The rotor includes a permanent magnet and a soft magnetic yoke. A hub is provided that is concentric to the yoke and is connected to the rotor for rotation therewith. The hub has a disk mounting portion on its outer peripheral surface that can be passed through the central opening of a standardized storage disk for mounting the storage disks for rotation therewith. At least half of the axial longitudinal dimension of the stator winding and the rotor magnet interacting therewith is housed within the disk mounting portion of the hub. The hub is made from a non-ferromagnetic material that is suitable for storage drive clean chamber use after dimensional finishing of the hub.

Abstract: A three-phase brushless dc motor includes a permanent-magnet rotor magnet arrangement having at least four poles and a Y-connected, or star-connected, three-phase stator winding. The winding's phases are arranged non-overlapping in slots of a slotted stator, the currents flowing in the three phases being controlled via at least three semiconductor elements by at least three magnetic-field-sensitive rotor position sensors. Each sensor is associated with a respective two of the winding's three phases and triggers a commutation which switches off the current in one of the associated two phases and switches on the current in the other of the associated two phases. The sensors are located to sense the permanent-magnet flux emanating from the rotor poles themselves. The rotor position sensors are provided at special angular locations on the stator.

Abstract: A disk storage device including a housing surrounding a clean chamber, at least one storage disk having a central opening, at least one data head mounted on the housing for movement in operative relationship with the disk within the clean chamber, and motor elements for rotating the disk within the clean chamber. The motor elements include a rotatable member positioned within the clean chamber. The rotatable member has a cylindrical outer surface portion that extends into the central opening of the storage disk and is supported by a shaft and bearing system. A stator including magnetically active parts is mounted on a support member, which also supports the shaft and bearing system. The stator has a magnetic flux-producing section having poles positioned on the same side of the support member as the rotatable member.

Abstract: A disk storage drive is provided with a brushless drive motor having a stator with a winding. An external rotor housing including a permanent magnet coaxially surrounds the stator and is spaced therefrom by a substantially cylindrical air gap. A hub is provided that is concentric to the rotor housing and is connected to the rotor housing for rotation therewith. A bearing above the stator rotatably supports an upper end of the rotor housing on a stationary shaft and a bearing below the stator braces the open end of the rotor housing by a ring element having substantially the same heat expansion characteristics as the rotor housing.

Abstract: A disk storage has one or more disks provided with center holes. An electric motor extends coaxially through these holes and has an external rotor to the outer circumference of which the disks are secured so that they rotate with the rotor. A seal is provided for at least reducing the escape of contaminants from the motor.

Abstract: A disk storage drive for a disk storage device having a clean chamber for a storage disk having a central opening is provided with a brushless drive motor. The drive motor includes a stator and a winding on the stator and further includes a shaft aligned with the rotation axis of said motor, and a magnetically conducting member supported for rotation about the rotation axis and having an inner wall coaxially surrounding the stator. A magnet fixed to the inner wall of the magnetically conducting member is radially spaced from the stator. The disk storage device further includes a hub positioned within the clean chamber and contiguous with the magnetically conducting member so that the hub and the magnetically conducting member together form an outer rotor of the drive motor. The outer rotor has a radially extending flange having a surface which supports said storage disk.

Abstract: A disk storage has one or more disks provided with center holes. An electric motor extends coaxially through these holes and has an external rotor to the outer circumference of which the disks are secured so that they rotate with the rotor. A seal is provided for at least reducing the escape of contaminants from the motor.

Abstract: A drive circuit for brushless DC motors comprising a rotor and a stator with at least one stator coil includes a commutation device which supplies commutation pulses of drive current to the stator coil(s). The commutation device senses the rotor position and calculates current rotor speed therefrom. The rotor speed is then used to shift the commutation currents according to predetermined functions. The shifting of commutation currents is occasioned by shifting either or both of the ignition part of a commutation pulse and the extinction part of such pulses.

Abstract: A disk storage has one or more disks provided with center holes. An electric motor extends coaxially through these holes and has an external rotor to the outer circumference of which the disks are secured so that they rotate with the rotor. A seal is provided for at least reducing the escape of contaminants from the motor.

Abstract: A disk memory drive includes a brushless drive outer rotor motor having an internal space and a stator with windings. The outer rotor coaxially encircles the stator and a substantially cylindrical air gap is defined between the stator and the rotor. The rotor includes permanent magnets and a hub fixedly connected with the magnet. A disk mounting section is provided on the hub for accommodating at least one storage disk positioned in a clear space, the mounting section being adapted to extend through a central aperture of the storage disk. The windings and the magnets interacting with the windings are disposed for at least half of the axial longitudinal dimension thereof within a space surrounded by the disk mounting section of the hub. Bearings rotatably mount the rotor and the hub.

Abstract: A compact motor mount for cassette drive systems includes a base plate in the form of a laminate that includes at least one planar layer of ferromagnetic material sandwiched between two printed circuit boards. A capstan motor is supported by the base plate. The stator coil assembly of the capstan motor is mounted on one side of the base plate directly on one of the two printed circuit boards. At least one winding drive motor also is supported in common with the capstan motor by the base plate. The stator coil assembly of the drive motor is mounted on the other side of the base plate directly on the second of the two printed circuit boards. Each of the motors has a permanent magnet rotor mounted on a shaft and facing the respective stator coil assemblies across an air gap defined therebetween.

Abstract: A disk memory drive includes a brushless drive outer rotor motor having an internal space and a stator with windings. The outer rotor coolly encircles the stator and a substantially cylindrical air gap is defined between the stator and the rotor. The rotor includes permanent magnets and a hub fixedly connected with the magnet. A disk mounting section is provided on the hub for accommodating at least one storage disk positioned in a clear space, the mounting section being adapted to extend through a central aperture of the storage disk. The windings and the magnets interacting with the windings are disposed for at least half of the axial longitudinal dimension thereof within a space surrounded by the disk mounting section of the hub. Bearings rotatably mount the rotor and the hub.

Abstract: The present invention relates to an integrated driving system for signal-processing devices, especially video devices (recorders), and other, preferably magnetic pulse recording devices, wherein the device chassis (1) and the mounting provision for at least two motors (20, 21, 22) are formed integrally with each other. The device chassis (1) proper also includes all mounting or bearing bores (e.g. 2, 50, 55) for all mounting shafts (e.g. 4, 8, 18) in a precise positional relation to each other. The bores (2, 50, 55) for all mounting shafts (4, 8, 18) and axles are formed in the metal-cast device chassis (1) in one or more machining operations without the necessity of re-chucking, ensuring that not only the active and passive driving sections of the driving system, but also the reference surfaces and bearing or supporting points are precisely positioned relative to each other.

Abstract: A brushless DC drive motor with an external rotor has three pole shoes on a substantially ring-shaped stator for each two poles on the rotor. The stator winding is commutated by a three-phase commutation network in such a fashion that first, second and third networks in the stator winding are cyclically connected to an external DC source in accordance with rotor position. Each of the networks comprises at least one stator coil wrapped around a neck of a single corresponding one of the pole shoes.

Abstract: The stator winding of a brushless D.C. motor receives two current pulses per 360.degree.-el. of rotor rotation, each current pulse being furnished via a respective current path. Each current path contains at least one power transistor switch having conductive and non-conductive states. These states are determined by respective driver transistor switches; when the driver transistor switch is in a high-output-impedance state the respective power transistor switch is rendered conductive, but when in the low-output-impedance state it renders the power transistor switch non-conductive. In various ways disclosed herein measures are taken to prevent the power transistor switches of both current paths from being simultaneously conductive. This may be accomplished using inherent or discrete base-emitter capacitances so connected that a power transistor switch is switched off abruptly but switches-on only after the elapse of a predetermined delay.