A spindle motor comprises a stationary shaft, a rotor hub rotatably mounted by ball bearings to the stationary shaft, and annular sealing members disposed between the outer surface of the stationary shaft and the inner side of the rotor hub axially outwardly of the ball bearings. The sealing member is directly fitted onto the outer race of the corresponding ball bearing. The outer race of each ball bearing is high precision finished so that the sealing member is definitely coaxial with the stationary shaft regardless of the finishing accuracy on the inner side of the rotor hub. Accordingly, the radial distance between the inner side of the sealing member and the outer surface of the stationary shaft can be minimized with high precision offering an excellent labyrinth effect.
Ultraviolet-transparent seals, flange, and sleeve assemblies are used in actuator pivot cartridges for hard disk drives to cure adhesive located inside the pivot housing. The assemblies are formed from silica glass, polymers, or other suitable materials, and focus UV light into hard to reach, high aspect ratio areas between the pivot bearings, sleeve, and shaft. Some of the assemblies use transparent components with convex or fresnel lenses formed into their geometry. With these designs, UV light can enter the pivots axially and/or radially to reach and cure the adhesive regardless of its location.
A pivot assembly for sustaining a magnetic head, a head suspension and an actuator block pivotally parallel to magnetic disks oscillates slowly. Hence the invention has been made in light of examining a sealing structure for retaining sufficient capability of preventing a leakage of lubricant and retaining sufficient capability of preventing a contamination of lubricant, characterized in that retaining required sealing capabilities, an annular shield plate is secured to the shaft, achieving pivot assembly manufacturing cost by reducing machining process and a number of sealing members.
The invention is a spindle motor including a rotor hub bearing a rotational load, lubricant-containing bearing systems rotatably supported by the rotor hub, and stator windings wound on a stationary member, so as to oppose the rotor magnet. At least a portion of the rotor hub is in a clean environment, with the motor substantially sealed by a sealing unit. The spindle motor has a leakage prevention unit which prevents the lubricant trying to leak out the bearing systems and out the motor, when centrifugal forces produced by a rotor hub rotating at a high speed are exerted on the lubricant.
A spindle-drive motor, especially for driving a hard drive, with a stator, a rotor, an axle between them having at least one bearing, and a drive, where the rotor or stator is provided with a bushing which accommodates at least one bearing. The bushing and bearing together form a sealing gap which seals the rotor and the stator with respect to each other.
A plurality of toroidal sealing plates 16a, 16b, and 16c spaced axially by slight gaps S.sub.1 and S.sub.2 are disposed between spindle 3 and vertical bore 6 of the rotor hub at above and/or below the bearing apparatus such that the outer or inner peripheral portion of each plate is secured to the inner peripheral portion of the bore of the rotor hub or the outer peripheral portion of the spindle so as to leave slight radial gaps .alpha..sub.1, .alpha..sub.2 and .alpha..sub.3 between the inner or outer peripheral portion of each plate and the outer peripheral portion of the spindle or the inner peripheral portion of the bore of the rotor hub to make each sealing plate uncontacted with the spindle or the bore, wherein the radial gaps are positioned alternately on the side of the spindle or on the side of the bore of the rotor hub.
