Abstract: The present invention relates to the field of fluid dynamic bearings. Specifically, the present invention provides a secondary fluid reservoir for the fluid used in a fluid dynamic bearing in a high-speed spindle motor assembly.

Abstract: A motor is provided comprising a rotor, a stationary sleeve disposed about the rotor, a fluid dynamic bearing between the rotor and sleeve, and a limiter for restricting axial movement of the rotor relative to the stationary sleeve.

Abstract: The present invention relates to the field of fluid dynamic bearings. Specifically, the present invention provides a secondary fluid reservoir for the fluid used in a fluid dynamic bearing in a high-speed spindle motor assembly.

Abstract: A fluid bearing design is provided which according to one aspect includes a shaft defining together with a surrounding sleeve an asymmetric journal bearing, and a thrust bearing at or near an end of the shaft towards which the asymmetric journal bearing is pumping, with that end of the shaft being closed off. The journal bearing asymmetry establishes a hydraulic pressure toward the closed end of the shaft. This pressure provides an axial thrust to set the bearing gap for the conical bearing. The conical bearing itself is a relatively balanced bearing, although it may have a bias pumping toward the shaft and the journal bearing.

Abstract: A method and apparatus for assembling a hydrodynamic bearing in a motor is provided. The method comprises affixing a first bearing upon a shaft, applying an axial tension force to the shaft, and affixing a second bearing upon the shaft in a spaced apart relation to the first bearing, as the axial force is applied to the shaft.

Abstract: The shaft may be supported for rotation by a conical bearing rotating within a sleeve. To prevent misalignment of the rotor and stator as the motor heats up and fluid viscosity changes, a magnetic preload is established; in a preferred embodiment, the magnetic preload is achieved using a magnetic back iron aligned with the stator magnet, the magnetic back iron being supported from the base. The shaft may further include a lower journal bearing for maintaining radial alignment and/or stiffness.

Abstract: Hard disk drive track density is increased by selectively increasing the stiffness of an FDB motor during servo write. Applying a load to the shaft of a fixed shaft FDB motor to close the bearing gaps increases stiffness. Alternatively, the disk drive is cooled to increase bearing fluid viscosity or the motor is operated at an increased rotational velocity.

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 method and apparatus for a conical bearing is provided having a seal shield having an angle supported from the hub or sleeve which surrounds the shaft, and extending at an angle toward the outer surface of the shaft and spaced slightly away from the upper angular surface of the cone. As the cone and seal shield rotate relative to one another, fluid is drawn toward the lower inner region of the reservoir. However, due to shock or the like, some fluid may reach the radial gap between the end of the shield and the outer surface of the shaft, therefore, a ring is either incorporated into the upper end of the cone or pressed against the axial outer end of the cone, defining an axial gap which is smaller than the radial gap. In a preferred form of the invention, the ratio is about 1:3.