Abstract: The present invention provides a bearing comprised of a hydrodynamic bearing and a pivot bearing, which can be used with a spindle motor. It also provides a spindle motor utilizing a hydrodynamic bearing and a pivot bearing.

Abstract: A variable reluctance resolver is provided with an output winding having a reduced effect from externally introduced leakage magnetic flux. A variable reluctance resolver is provided with a resolver excitation winding and a resolver output winding wrapped around multiple stator magnetic poles which respectively output rotary angle X and Y components as a rotor turns. Windings are wound such that the polarities of output voltages on output windings wound around a row of three or more stator magnetic poles will be the same; all of the output windings are divided into an even number, two or greater, of groups, and output windings are serially connected in such a way that adjacent group output voltage polarities mutually differ.

Abstract: To realize an adaptive antenna array system which improves reception quality of desired signals by properly suppressing interference signals. The system includes: a signal detection section which detects base station signals from signals received by antenna elements; a control section which selects desired signals and interference signals to be cancelled from among the detected base station signals; a spatial signature detection section which detects spatial signatures of the desired signals and the interference signals to be cancelled; a virtual-signal generation section which generates virtual-signals for the interference signals to be cancelled using the spatial signatures thereof; an array weight generation section which generates array weights for the antenna elements by multiplying the inverse matrix of a correlation matrix of the virtual-signals by the spatial signatures of the desired signals; and a signal combining section which combines the received signals using the array weights.

Abstract: A process for manufacturing miniature ball bearings that reduces material loss to improve manufacturing efficiency. The process consists of obtaining an inner and outer ring blank by cutting a first blank, forging the first blank to obtain a final blank, and separating the final blank to form an outer ring blank and an inner ring blank. The outer ring blank has an outer diameter of at most 13 mm. Cutting the first blank is performed by mechanically cutting and machining.

Abstract: An electric motor, particularly an electronically commutated direct current motor, has a stator and a rotor. The stator and the rotor are arranged coaxially to a longitudinal axis of the electric motor. The stator features a plurality of electrical stator poles and a plurality of phase windings. The rotor features a permanent magnet with a least one magnetic pole pair which is dedicated to the phase windings. The phase windings and/or the permanent magnet are divided into several axial sections in the direction of the longitudinal axis of the electric motor and these sections are staggered around the longitudinal axis of the electric motor with respect to each other. Angular positions of the individual phases are offset with respect to each other is in such a way that torque ripple can be reduced and torque gaps can be prevented.

Abstract: Hydrodynamic bearing for use in a spindle motor includes a shaft, a bearing sleeve encompassing the shaft with a small radial clearance, a plurality of hydrodynamic pressure generating grooves formed on at least one of an outer surface of the shaft and an inner surface of the bearing sleeve, and a base-plate, flange or another frame element of the motor. The bearing sleeve is constructed as a single component with the frame element of the motor.

Abstract: An apparatus for and a method of construction of a spindle motor having a bearing unit, a rotary shaft, a rotary hub member and an electro-magnetic motor is presented. The rotary shaft has a flange attached at a mid-section in an axial direction, between large and small diameter sections of the rotary shaft. Grooves between the bearing unit, rotary shaft and flange create radial dynamic pressure generating areas, each with as long as possible a span, and thrust dynamic pressure generating areas to both sides of the flange.

Abstract: A process for manufacturing miniature ball bearings that reduces material loss to improve manufacturing efficiency. The process consists of obtaining an inner and outer ring blank by cutting a first blank, forging the first blank to obtain a final blank, and separating the final blank to form an outer ring blank and an inner ring blank. The outer ring blank has an outer diameter of at most 13 mm. Cutting the first blank is performed by press cutting.

Abstract: A method and apparatus for verifying the integrity of devices on a target network. The apparatus has security subsystems and a master security system hierarchically connected to the security subsystems via a secure link. The target network includes various intrusion detection devices, which may be part of the security subsystem. Each intrusion detection device generates a plurality of event messages when an attack on the network is detected. The security subsystem collects these event messages, correlates, and analyzes them, and performs network scanning processes. If certain events warrant additional scrutiny, they are uploaded to the master security system for review.

Abstract: A hydrodynamic thrust bearing forming a part of a bearing system for a rotary bearing of spindle motors utilized to power hard disk drives. The thrust bearing includes at least one annular thrust plate and a counter bearing corresponding to the thrust plate. The thrust plate is firmly connected to a shaft rotatably supported by a radial bearing system. The shaft features an axial bore in the area of the thrust bearing, into which a fixing element is inserted. The fixing element is at least partially provided with a spherical surface. The element is inserted in such a way that the surface of the sphere projects slightly from the end of the shaft and rests on the counter bearing, at least when the motor is at a standstill. Therefore, when the motor is standing still or particularly during its start-up or shut-down phase, the spherical element (and not the bearing surface of the thrust plate) rests on the bearing surface of the cover plate.

Abstract: A spindle motor for use in a disk drive having a rotor assembly and a stator assembly. The rotor assembly has a hub and a rotating shaft with an outer diameter, the hub being mounted for rotation on the rotating shaft. The stator assembly has a bearing sleeve with a bottom opening, the rotating shaft being inserted into the bearing sleeve for rotation. A counter-plate is inserted into the bottom opening of the bearing sleeve thereby closing the bottom opening. A thrust plate is mounted on the rotating shaft in opposing relationship with the counter-plate, the thrust plate having an outer diameter. A fluid dynamic thrust bearing is formed between the counter-plate and the thrust plate. A ratio between the outer diameter of the shaft to the outer diameter of the thrust plate is reduced to reduce spindle motor's power consumption.

Abstract: A stator device which prevents the formation of varnish accumulations on jumper wires, thereby preventing jumper wire breakage due to temperature variations. A gap is created between the jumper wire and the stud located on the stator body. When varnish is applied to the stud and the jumper wires, excess varnish flows through the gap and pools underneath. Moreover, when there is a significant accumulation of varnish in the gap, the varnish will flow off from the edge of the stator body.

Abstract: A hydrodynamic bearing system for use in spindle motors having a shaft and a bearing sleeve. At least one bearing member is mounted an outer surface of the shaft. A fluid trap member is further provided in the bearing system, the fluid trap member being integrated into the bearing member. A fluid trapping cavity is formed between the fluid trap member and a surface of the bearing member.

Abstract: A spindle motor for use in a disk drive, the spindle motor including a shaft having a larger diameter section and a smaller diameter section with a step formed therebetween. The spindle motor also includes a bearing sleeve having a central cylindrical opening, the shaft is inserted into the central cylindrical opening. A bearing gap is formed between the shaft and the bearing sleeve, the bearing gap being filled with lubricating fluid. A thrust plate is fixedly mounted on the shaft in the area of the step such that an upper side of the thrust plate is placed adjacently to the larger diameter section and a lower side of the thrust plate is placed adjacently to the smaller diameter section of the shaft.

Abstract: A rear casing (inner casing) 50 that fits into a front casing (outer casing) 40, where a stator 20 is held between these casings 40 and 50. The front casing 40 and the casing [SIC] 50 are rigidly adhered to each other through caulking, adhesives, or welding. Furthermore, the elastic parts 46 that provide an elastic force on the stator 20 towards the rear casing 50 at the step part 43 of the front casing 40, where the stator 20 is press fitted, and the restorative force of the elastic pieces 46 strongly holds the stator 20.

Abstract: A hydrodynamic bearing having a shaft (10) and a bearing sleeve (12), which encloses the shaft with a slight radial clearance forming a concentric bearing gap. An equalizing volume cavity (20) is formed at at least one end of the bearing. At least one micro-passage (26) connects the bearing gap via appropriate openings with the equalizing volume cavity (20). Bearing fluid completely fills the bearing gap (24) and the micro-passage (26) and at least partially fills the equalizing volume cavity (20). The bearing fluid forms a continuous fluid film between the bearing gap (24) and the equalizing volume cavity (20).

Abstract: A rotor assembly for an electric motor having a rotor shaft and at least one permanent magnet arranged on the rotor shaft. The rotor shaft with the permanent magnet is accommodated in a sleeve the rotor shaft being freely rotatable within the sleeve. The sleeve is closed off by a flange at a first end face. An inner-rotor electric motor having a stator and a rotor assembly of the type described above, with the stator being inserted over the sleeve of the rotor assembly.

Abstract: A keyboard switch with an internal air escape network, such as a series of channels or through holes, for containing air or fluid escaping from the switching cavities when a key is depressed.

Abstract: A hydrodynamic thrust bearing, particularly forming a part of a bearing system for a rotary bearing of spindle motors utilized to power hard disk drives. The thrust bearing includes at least one annular thrust plate and a counter bearing corresponding to the thrust plate. The thrust plate is fixedly mounted on a shaft rotatably supported by means of a radial bearing system. The thrust plate is arranged on the shaft which is provided with an axial bore in the area where the thrust plate is to be positioned. A spherical element fixing the thrust plate is pressed into the axial bore. An outer diameter of the fixing element is greater than the inner diameter of the axial bore. This type of press connection between the thrust plate and the shaft allows comparatively thinner thrust plates to be used while the performance of the thrust bearing remains the same or improves.

Abstract: A spindle motor for a hard disk drive having a stationary component with a first bearing surface, and a rotating component with a second bearing surface located in opposing relationship with the first bearing surface. The first and the second bearing surfaces form a hydrodynamic bearing. A bearing gap is formed between the first bearing surface and the second bearing surface, the bearing gap being filled with lubricating fluid. An oil-free recess is provided in the motor for placement of electromagnetic components of the motor. The stationary component is provided with a first set of seal surfaces, and the rotating component is provided with a second set of seal surfaces. The seal surfaces of the first set are located opposite the seal surfaces of the second set and form a labyrinth seal sealing the bearing gap from the oil-free motor recess.