Abstract: A magnetic fluid seal is provided by mounting an annular, axially polarized magnet mounted on the device base member and an annular ring pole piece with an inner diameter that cooperates with an outer diameter surface of the hub assembly to form a fluid gap that is radially outward and within the axial extent of the spindle bearings. The secondary gap of the seal assembly is within the bearing assembly sealed volume while the principal sealing gap is within the hub assembly to confine any debris or aerosols resulting from high rotational velocity or shock to be contained in proximity to the flux fields that can recapture any magnetic material. The assembly also inherently presents an effective conductive path to provide enhanced grounding of the rotating assembly through the magnetic fluid in the second gap which is not subject to impairment caused by bonding materials.

Abstract: A data storage disk drive is provided with a spindle which supports a plurality of disks having at least one magnetic disk surface to form a spindle assembly for rotation of the disk surfaces about a common axis and a rotary actuator which supports magnetic transducers for movement in unison about respective disk surfaces. The disk drive includes a voltage reference tab provided for quick assembly and removal from an actuator comb. The voltage reference tab maintains the magneto-resistive transducers and the magnetic disks at the same reference voltage potential thus minimizing electrical discharge from the transducer to the disk. The voltage reference tab is a copper tab having symmetrical slots about a fastening hole to facilitate the bending operation and to reduce the rate at which heat is conducted during the soldering process. The tab maintains the voltage reference potential between the head and disk through an extension of the flex cable attached to the actuator.

Abstract: The hub includes a cup attached to the hub or rotating portion of the disk drive. The cup has a top. Both the cup and top have openings therein which accommodate the fixed shaft. The cup is filled with ferrofluid. The portion of the shaft passing through the cup and top is magnetized so magnetic seals are formed at the openings. Electrical charge is transmitted to the shaft via the cup and the ferrofluid. A similar arrangement is shown for a disk drive having a rotating shaft in which the cup is incorporated into the hub and a magnetized pin attached to the housing is inserted into the cup.

Abstract: A magnetic seal for a disk drive data storage unit is described where the magnet assembly comprising an annular magnet and two annular pole pieces are adhesively attached with the magnet intermediate the pole pieces and the assembly thereof then forcibly inserted, creating a force fit, into a shield which is formed as an annulus with an interior cylindrical surface engaging the exterior cylindrical surfaces of the magnet assembly. The force fit insures electrical continuity between the shield and the pole pieces. The shield extends into close proximity with the shaft being sealed and is provided with a relieved region immediately adjacent the interior cylindrical surface of the pole pieces to form a reservoir for receiving, trapping and retaining any ferromagnetic fluid which may escape from the gap between the pole pieces and the shaft. A mating shield is then assembled onto the previously assembled components after the introduction of the ferromagnetic fluid into the seal gaps.

Abstract: Disclosed is a disk drive having an enclosure for housing one or more disks, an actuator arm and sliders attached to the actuator arm. The sliders include magnetic transducers for reading information related to data off the disk and for writing representations of data to the disk. In a disk drive with an in-hub, fixed spindle shaft motor, the disk or disks are attached to the hub which is rotatably mounted to the spindle shaft. The hub includes one or more fingers attached to the hub which touch the spindle shaft when the hub is stationary and when the hub is rotating. The spindle shaft may also be provided with a wear resistant layer and/or ring of conductive material to enhance the electrical pathway between the hub and the spindle shaft and provide for lower wear and a longer life.