Abstract: A method for erasing a disk of a hard disk drive. The method includes moving the hard disk drive adjacent to an erasure head that emanates a magnetic field. The magnetic field and moving hard disk drive cause a disk of the hard disk drive to spin under a Lorentz force created by the magnetic field and moving disk. The magnetic field is applied by the erasure head for a duration that causes erasure of the entire disk. The spindle motor is not activated during the entire process. Not activating the spindle motor eliminates any Faraday coupling from the erasure head into the motor.

Abstract: A method for erasing a disk of a hard disk drive. The method includes moving the hard disk drive adjacent to an erasure head that emanates a magnetic field. The magnetic field and moving hard disk drive cause a disk of the hard disk drive to spin under a Lorentz force created by the magnetic field and moving disk. The magnetic field is applied by the erasure head for a duration that causes erasure of the entire disk. The spindle motor is not activated during the entire process. Not activating the spindle motor eliminates any Faraday coupling from the erasure head into the motor.

Abstract: A spindle motor includes a shaft defining a longitudinal axis, a hub, a bearing assembly disposed between the hub and the shaft for allowing the hub to rotate, and a stator. The stator includes an inner diameter, an outer diameter, a stator tooth having a distal end, and a coil wound around the stator tooth. The stator tooth has a lower surface extending between the coil and the distal end of the stator tooth. The spindle motor includes a stator support structure supporting one of the inner and outer diameters, the stator support structure having an upper surface facing the lower surface, wherein at least one of the upper surface of the stator support structure and the lower surface of the stator tooth defines a cavity.

Abstract: A disk drive includes a disk drive base, a disk, and a head stack assembly rotatably coupled to the base adjacent the disk surface of the disk. The disk drive includes an airflow channeling enclosure. The enclosure includes an airflow inlet disposed downstream of the head stack assembly and configured to receive the disk rotation induced airflow therethrough. The enclosure further includes an airflow channel extending along the disk surface from the airflow inlet. The enclosure further includes an outer wall extending along the disk surface from the airflow inlet and defining the airflow channel radially interior to the outer wall. The enclosure further includes an airflow outlet disposed upstream of the head stack assembly extending from the outer wall and the channel opposite the airflow inlet for modifying the disk rotation induced airflow passing from the channel.

Abstract: A disk drive including a disk drive base, a disk coupled to the disk drive base, and a head stack assembly coupled to the disk drive base. The disk drive further includes an airflow diverter filter component disposed upstream of the head stack assembly with respect to disk rotation induced airflow for modifying the disk rotation induced airflow adjacent the head stack assembly. The filter component includes a first filter element disposed adjacent the disk surface, a second filter element disposed between the first filter element and the head stack assembly, and a third filter element having a porosity finer than the first and second filter elements. The third filter element is generally radially further than the second filter element from the axis of rotation. The disk rotation induced airflow generally enters the filter component through the first filter element and exits through the second and third filter elements.

Abstract: A disk drive spindle air bearing includes an air bearing gap between a pair of air bearing surfaces that varies as a function of radial distance from an axis of rotation. This non-uniform air bearing gap effectively minimizes contact between the air bearing surfaces of the bearing when the disk drive hub is at rest or spinning below a threshold speed. This reduced contact significantly reduces the stiction forces that must be overcome during disk drive spin up operations and also reduces the generation of wear particles within the bearing. Air bearing surface shaping techniques are provided for achieving the non-uniform gap dimension, including techniques involving crowned, stepped, and sloped surfaces. In an alternative approach, sacrificial plating is employed to achieve a non-uniform gap dimension within the air bearing.

Abstract: A disk drive spindle air bearing is disclosed having increased bearing stiffness, while being capable of manufacture using conventional tolerances. The invention therefore allows the construction of a disk drive spindle bearing without the need for oil or grease that may potentially contaminate the storage disks. The disclosed disk drive spindle air bearing also provides an air bearing having low acoustical noise and power consumption characteristics.

Abstract: A coating system and method for facilitating the cleaning of hydrodynamic bearings and their associated structure is effectuated by applying a surface energy lowering coating to selected portions of the bearing other than the surface tension seal producing gaps thereof prior to a lubricant fluid fill. The coating system and method of the present invention may also advantageously be utilized to produce a secondary barrier seal extending a relatively short distance within and adjoining the opening of the surface tension seal producing gaps.

Abstract: A method for forming a precision groove in a cylindrical surface of an article such as a sleeve-shaft hydrodynamic journal bearing system includes the steps of: aligning a groove-forming machine to an axial datum plane of the article defined in a spaced-apart relation with the cylindrical surface by a predetermined nominal first dimension, translating the groove-forming machine in an axial direction toward and upon a first edge of the cylindrical surface by an amount equal to the predetermined nominal first dimension and thereupon forming a first groove axial step segment in the cylindrical surface until a second predetermined axial datum plane is reached, simultaneously axially translating and rotating the groove-forming machine from the second axial datum plane until a third predetermined axial datum plane is reached and thereupon forming the precision groove pattern in the cylindrical surface between the second axial datum plane and the third axial datum plane, and axially translating the groove-forming ma

Abstract: A method for forming a precision groove in a cylindrical surface of an article such as a sleeve-shaft hydrodynamic journal bearing system includes the steps of: aligning a groove-forming machine to an axial datum plane of the article defined in a spaced-apart relation with the cylindrical surface by a predetermined nominal first dimension, translating the groove-forming machine in an axial direction toward and upon a first edge of the cylindrical surface by an amount equal to the predetermined nominal first dimension and thereupon forming a first groove axial step segment in the cylindrical surface until a second predetermined axial datum plane is reached, simultaneously axially translating and rotating the groove-forming machine from the second axial datum plane until a third predetermined axial datum plane is reached and thereupon forming the precision groove pattern in the cylindrical surface between the second axial datum plane and the third axial datum plane, and axially translating the groove-forming ma

Abstract: A self-contained hydrodynamic bearing unit includes a shaft and a shaft housing defining an opening for receiving the shaft for relative rotation. The shaft and bearing define at least one radial hydrodynamic bearing and an annular thrust bearing, formed as a disk portion extending radially outward of a main cylindrical surface of the shaft which cooperates with an adjacent annular face of the shaft housing. A gap between an outer cylindrical wall of the thrust bearing disk portion and an adjacently facing cylindrical surface of the shaft housing provides a primary annular capillary seal segment. An annular bushing ring extends from the housing radially inwardly to enclose the thrust bearing disk, and cooperates with an adjacent outer face of the thrust bearing disk to provide a secondary containment capillary seal segment. Normally, lubricating liquid is in the bearing unit at the radial hydrodynamic bearing, at the hydrodynamic thrust bearing and in the primary annular capillary seal segment.

Abstract: A self-replenishing hydrodynamic bearing unit comprises a shaft and housing defining an opening for receiving the shaft for relative unidirectional rotation. A plurality of reservoirs contain a lubricating fluid. A hydrodynamic bearing region lies between the plurality of reservoirs for providing a rotational journal for relative rotation between the shaft and the housing. At least one of the shaft and the housing defines a continuous pattern of herringbone or Vee-shaped pumping grooves or passages which communicate between the plurality of reservoirs for pumping the lubricating fluid during relative rotation. The groove pumping creates a pressurized hydrodynamic bearing lubricant film at the bearing region with each groove generating localized unidirectional directional flow of lubricating liquid between the reservoirs along a predetermined axial direction of rotation, wherein some passages create axial flow in a forward direction and the others create axial flow in a reverse direction.