Abstract: A rotating hub and fixed spindle assembly with first and second fluid dynamic journal bearings and first and second fluid dynamic thrust bearings for a disc drive memory system has a pump seal and a radial ring seal at a first axial terminus for lubricant containment, and a capillary seal and a labyrinth seal at a second axial terminus for lubricant containment and storage. Lubricant fluid pressure differences between first and second seals are minimized through one or more lubricant fluid communicating channels in the hub assembly, in order to minimize lubricant fluid loss through a seal. Lubricant fluid can also be purged of any air bubbles by lubricant fluid circulation through the channel.

Abstract: A rotating hub and fixed spindle assembly with first and second fluid dynamic journal bearings and first and second fluid dynamic thrust bearings for a disc drive memory system has a pump seal and a radial ring seal at a first axial terminus for lubricant containment, and a capillary seal and a labyrinth seal at a second axial terminus for lubricant containment and storage. Lubricant fluid pressure differences between first and second seals are minimized through one or more lubricant fluid communicating channels in the hub assembly, in order to minimize lubricant fluid loss through a seal. Lubricant fluid can also be purged of any air bubbles by lubricant fluid circulation through the channel.

Abstract: Multifunctional components enable the construction of economical motor assemblies. A first embodiment of the present invention provides a hub, cup, spindle, and base assembly for a motor assembly having at least one journal bearing, at least one thrust bearing, and at least one fluid seal. A second embodiment of the present invention provides a hub, spindle, and base with integrated cup assembly for a disc drive bearing having at least one journal bearing, at least one thrust bearing, and at least one fluid seal. In a third embodiment, a hub is rotatably assembled with a spindle coupled to a thrust bearing, prior to assembly with a base. In further embodiments, motor assemblies comprise the above embodiments combined with stator and rotor assemblies.

Abstract: A rotating hub and fixed spindle assembly with first and second fluid dynamic journal bearings and first and second fluid dynamic thrust bearings for a disc drive memory system has a pump seal and a radial ring seal at a first axial terminus for lubricant containment, and a capillary seal and a labyrinth seal at a second axial terminus for lubricant containment and storage. Lubricant fluid pressure differences between first and second seals are minimized through one or more lubricant fluid communicating channels in the hub assembly, in order to minimize lubricant fluid loss through a seal. Lubricant fluid can also be purged of any air bubbles by lubricant fluid circulation through the channel.

Abstract: In one example, an FDB motor having a shield member is provided. In one example, the method includes disposing a first member and a second member for relative rotation about an axis of rotation. An annular shield member is attached to the first member, the shield member disposed adjacent a fluid reservoir for containing a bearing fluid. The reservoir is filled through an aperture (e.g., a fill hole) in the shield member. Thereafter, the aperture is at least partially sealed. The aperture may be hermetically sealed via one or more laser pulses. In other examples, a two piece shield is provided for shielding a reservoir without a fill hole.

Abstract: In one example, a FDB motor having a top-cover attached, EM biased bearing system is provided. The motor includes a shaft and rotor disposed for relative rotation, and an axial limiter for restricting axial movement of the rotor with respect to the shaft, wherein the axial limiter is wet or lubricated during contact. The limiter is spatially fixed with respect to one of the shaft or the rotor and disposed with an axial end surface opposing a surface portion spatially fixed with respect to the other of the shaft or the rotor to form a gap therebetween. The gap may be filled with a fluid such as bearing lubricant, thereby providing a lubricated or wet contact surface to restrict axial movement of the shaft and rotor. Additionally, one or both surfaces may include a groove or slot to provide circulation of fluid through the gap.

Abstract: An apparatus and method are provided for sealing an outer surface 170 of a shaft 175 to an inner surface 165 of a hub 160. The seal includes a magnet 155, with top and bottom pole pieces 260, 265, and a ferrofluid 270 magnetically held in a gap 275 between the pole pieces 260, 265, and the hub 160 or the shaft 175. The top pole piece 260 has a cross-section that is L-shaped, with a horizontal portion 260a parallel to the magnet 155 and a shorter vertical portion 260b facing the shaft 175. In one version, the vertical portion 260b or the portion of the shaft 175 facing it is contoured to provide a flux gradient that axially concentrates the ferrofluid 270 in the gap 275. In another aspect, a catcher 335 is provided to reduce loss of ferrofluid 270 when the ferrofluidic seal 185 used to form an outside seal. In yet another aspect, a stationary ferrofluidic seal 345 is provided for sealing a stationary shaft 350 to a rotating hub 355.

Abstract: A robust spindle motor is provided having added shock resistance for fluid containment. In an aspect, a high-speed centrifugal capillary seal contains a fluid reservoir extending between similarly rotatable components. Fluid is recirculated through the motor and substantially around a counterplate. Proper axial positioning of motor components and stiffness is maintained in motors supporting heavy loads such as a disk drive memory system having a weighty disc pack. In an aspect, two separate thrust surfaces provide oppositely directed axial forces acting on motor components. In an aspect, a single thrust plate that is comparatively small is utilized, reducing power consumption. Also, a thrust bearing situated inboard of a capillary seal forms a comparatively small diameter thrust plate gap. The comparatively small diameter thrust plate gap increases efficiency and characteristics including surface flatness, run out and perpendicularity are improved.

Abstract: The present invention provides a hydrodynamic bearing design which is simple and reliable in design, while incorporating a shaft with a plug of high elastic modulus material fitted within a cylinder of a lower elastic modulus material than that of the plug, thereby compensating for temperature variations while maintaining radial stiffness of the system over a wide range of temperatures. The design is relatively inexpensive and easy to replicate in a high volume manufacturing process.

Abstract: It is therefore an objective of the present invention to provide a hydrodynamic bearing design, which is simple and reliable in design, while incorporating means for compensating for temperature variations while maintaining the radial stiffness of the system.

Abstract: A spindle for a disc drive which can be assembled without the use of adhesives is disclosed. Stator electromagnets are encapsulated in a plastic overmold. The stator is clamped to the base with a clamp spring arrangement. An offset between the stator surface and the base flange is covered by a clamp spring such that binding of the clamp spring by a fastener allows for an adjustable biasing force to secure the stator in place. The magnet and flux shield are attached to the rotor sleeve by an easily positioned retaining ring. An elastic foam washer provides a controlled force to secure the magnet and flux shield in place on the rotor. A second elastic foam washer and a shield provide a controlled biasing force to hold magnetic fluid and magnetic poles to the rotor. Bearings are laser welded to the rotor and the shaft to rotatably mount the rotor about the shaft.