Abstract: A hydrodynamic bearing system where the bearing includes a shaft and two independent bearings, including a top cone or bi-sphere and a bottom cone or bi-sphere separated by a segment of the shaft. The bearing includes a hub supported bearing element rotating around the shaft and the shaft supported top cone and bottom cone; complementary surfaces of the bearing element and the cone define a narrow gap between the bearing support element for the bearing fluid. Sealing plates or seal elements define a fluid gap with a radially extending face of the cone; a gap also exists between an interior surface portion of each cone and the shaft. These gaps are connected so that separate flow paths are established, one around the top cone or bi-sphere and one around the bottom cone or bi-sphere. By providing two independent bearings, the stator can be mounted to the shaft, facing magnets supported on the hub to form an in-hub motor.

Abstract: A hub and shaft are provided which are mounted for relative rotation by providing two conical bearings spaced apart along the shaft, and a bearing seat facing each conical bearing. Fluid is maintained in the gap between each cone and the facing bearing seat, supporting the cone and seat for relative rotation. The outer surface of the bearing seat is insulated from the remainder of the motor by a thermal insulator which extends at least part way along the outer surface of the seats. This insulator is effective at keeping the bearings warm even in a relatively low temperature environment in which the motor may be used. The insulator may comprise a cylindrical ceramic or similar low thermal conductivity material extending at least part way along the axial distance outside of the bearing cones. Alternatively, an air space may be defined in the outer surface of the bearing seat, extending at least part way between the bearing cones.

Abstract: A hydrodynamic bearing having a shaft relatively rotatable with rest to a surrounding sleeve and having a thrust plate of or near one end thereof. The shaft and sleeve define a journal bearing extending substantially the full length of the two relatively rotating parts.

Abstract: A hydrodynamic bearing system where the bearing includes a shaft and two independent bearings, comprising a top cone or bi-sphere and a bottom cone or bi-sphere separated by a segment of the shaft. The bearing includes a hub supported bearing element rotating around the shaft and the shaft supported top cone and bottom cone; complementary surfaces of said bearing element and said cone define a narrow gap between the bearing support element for the bearing fluid. Sealing plates or seal elements define a fluid gap with a radially extending face of the cone; a gap also exists between an interior surface portion of each cone and the shaft. These gaps are connected so that separate flow paths are established, one around the top cone or bi-sphere and one around the bottom cone or bi-sphere. By providing two independent bearings, the stator can be mounted to the shaft, facing magnets supported on the hub to form an in-hub motor.

Abstract: A magnetic disc drive system includes a hydrodynamic bearing. The magnetic disc drive system includes a disc drive chassis, a magnetic storage disc, and a read/write transducer adjacent to the disc for reading and writing information on the disc. The hydrodynamic bearing assembly rotatably couples the magnetic storage disc to the disc drive chassis. The hydrodynamic bearing assembly includes a fluid path therethrough for circulating a fluid. A permanent magnet is placed in the fluid path and used for attracting magnetic particles carried in the fluid.

Abstract: For a precision spindle motor, an invention for reducing distortion resulting from interference fits of a thrust plate to spindle motor shaft and of a counter plate to a journal. A method of assembly according to the invention includes the step of balancing an interference pressure about a centerline of at least one of the thrust plate and the counter plate of the spindle motor. A precision spindle motor according to the invention comprises a journal having a bore defined therein, a shaft located in the bore, a thrust plate mounted to a top portion of the shaft by means of an interference fit, and a counter plate mounted to the journal adjacent to the thrust plate by means of an interference fit, wherein an interference pressure is balanced about a centerline of at least one of the thrust plate and the counter plate.

Abstract: The hydrodynamic bearing arrangement comprises a journal sleeve defining a journal bore and a journal thrust surface. A shaft is mounted in the journal bore by means of a hydrodynamic journal bearing which permits rotation of the shaft and the journal sleeve relative to one another. A thrust plate extends transversely from the shaft and defines two hydrodynamic thrust bearings in combination with the journal thrust surface and a counterplate which is mounted adjacent to the thrust plate. A porous lubricant reservoir is mounted adjacent to the thrust plate. The porous lubricant reservoir serves to remove wear particles from the lubricant in the bearing arrangement, and provides a supply of lubricant to the hydrodynamic journal and thrust bearings should they become depleted of lubricant.

Abstract: For a precision spindle motor, an invention for facilitating interference fits of a thrust plate to spindle motor shaft and of a counter plate to journal. A method is provided for assembling a spindle motor using press fits of a thrust plate to a shaft having an undercut for providing a relief to reduce unwanted translation into a thrust gap. A method is also provided for assembling a spindle motor using a press fit of a counter plate to a journal. The counter plate having a chamfer for reducing unwanted translation of the counter plate into a thrust gap. Also, the apparatus employed for the above methods are described.