Disk drive with self sealing screw attachment of actuator pivot
View Patent ↗A disk drive enclosure includes a cover and a base having a first hole therethrough. A head actuator is pivotably attached to the base by an actuator pivot bearing having a pivot bearing shaft with a lower internally threaded section and a flat annular support surface that is facing and in preloaded contact with a flat mating surface of the disk drive base around the first hole. A bearing member is disposed around the pivot bearing shaft and between the pivot bearing shaft and the bore of the actuator. A first screw has an externally threaded section that is engaged with the lower internally threaded section of the pivot bearing shaft. The first screw has a screw head with an external annular seating surface in contact with and forming a continuous annular seal with an internal annular seating surface of the first hole.
1. A disk drive comprising:
a disk drive enclosure including a disk drive base and a disk drive cover, the disk drive base including a first hole therethrough, the first hole including an internal annular seating surface;
a head actuator within the disk drive enclosure, the head actuator pivotably attached to the disk drive base by an actuator pivot bearing, the actuator pivot bearing including
a pivot bearing shaft disposed within a bore of the head actuator, the pivot bearing shaft including a lower internally threaded section aligned with a pivot axis of the head actuator, the pivot bearing shaft having a flat annular support surface that is facing and in preloaded contact with a flat mating surface of the disk drive base around the first hole;
a bearing member disposed around the pivot bearing shaft and between the pivot bearing shaft and the bore of the actuator; and
a first screw having an externally threaded section that is engaged with the lower internally threaded section of the pivot bearing shaft, the first screw having a screw head with an external annular seating surface in contact with and forming a continuous annular seal with the internal annular seating surface of the first hole.
2. The disk drive of claim 1 wherein the external annular seating surface of the screw head is a beveled surface.
3. The disk drive of claim 1 wherein the pivot bearing shaft comprises series 300 stainless steel.
4. The disk drive of claim 1 wherein the internal annular seating surface of the first hole is a beveled surface.
5. The disk drive of claim 1 wherein the first screw comprises series 400 stainless steel.
6. The disk drive of claim 1 wherein the disk drive base comprises aluminum.
7. The disk drive of claim 1 wherein the pivot bearing shaft further comprises an upper internally threaded section coupled to the disk drive cover by a second screw.
8. The disk drive of claim 1 wherein the pivot bearing shaft further comprises an annular boss that extends into the first hole.
9. The disk drive of claim 8 wherein the cylindrical outer surface of the annular boss is in slip fit contact with the first hole.
10. The disk drive of claim 8 wherein the cylindrical outer surface of the annular boss is radially separated from the first hole by a clearance, so that the first screw is self-centering.
11. The disk drive of claim 8 wherein the pivot bearing shaft comprises an outer shaft component that includes the annular boss, and an inner shaft component that includes the lower internally threaded section, the inner shaft component being nested within the outer shaft component.
12. The disk drive of claim 1 wherein the pivot bearing shaft is a single component having material continuity rather than being an assembly of subcomponents.
13. The disk drive of claim 1 wherein the disk drive enclosure is helium-filled.
14. The disk drive of claim 1 further comprising a spindle motor attached to the disk drive base, and a disk mounted to a rotatable hub of the spindle motor within the disk drive enclosure.