Abstract: A method of redefining nodal points of rotation comprises providing an actuator assembly with a comb, a pivot having an axis of rotation, comb legs on one side of the pivot, a voice coil motor, an arm, and a head gimbal assembly mounted to the arm with a head opposite the arm; defining a first nodal point of rotation for the actuator at a position that is on the arm between the pivot and the head; defining a second nodal point of rotation for the actuator at a position adjacent to the pivot and the coil; moving the first nodal point in a radial direction away from the axis toward the head; and moving the second nodal point in a radial direction away from the pivot to a geometric center of active legs of the coil.

Abstract: The dynamics of a disk drive actuator are enhanced by redistributing the mass and stiffness of the structure. The two nodal points of the second primary bending mode of the actuator are relocated to positions that are both radially outboard of their original positions. One nodal point is positioned as close to the read-write head as possible at one end of the actuator, and the other nodal point is positioned at the center of the active legs of the VCM coil at the other end of the actuator. This is done to reduce the off-track displacement associated with this fundamental resonance to near zero, allowing higher track densities to be supported.

Abstract: The dynamics of a disk drive actuator are enhanced by redistributing the mass and stiffness of the structure. The two nodal points of the second primary bending mode of the actuator are relocated to positions that are both radially outboard of their original positions. One nodal point is positioned as close to the read-write head as possible at one end of the actuator, and the other nodal point is positioned at the center of the active legs of the VCM coil at the other end of the actuator. This is done to reduce the off-track displacement associated with this fundamental resonance to near zero, allowing higher track densities to be supported.

Abstract: A lubricant retention design for a fluid dynamic bearing design in a spindle motor utilizes a labyrinth gap that is formed between the sleeve and the shaft of the bearing. The gap is used in conjunction with a barrier film to impede the flow of lubricant into the lateral and axial vent holes during non-operational vibration, such as shipping and handling of the end product. In another version, a plug is located in the lateral vent hole. The plug has a very small passage that permits air to pass therethrough for atmospheric pressure equalization, but prevents the escape of lubricant into the vent holes. Alternatively, the plug may be formed from a non-wettable material such as porous foam or sintered material and provided with a larger opening. Yet another solution utilizes a combination of both the labyrinth and plug designs.

Abstract: A lubricant retention design for a fluid dynamic bearing design in a spindle motor utilizes a labyrinth gap that is formed between the sleeve and the shaft of the bearing. The gap is used in conjunction with a barrier film to impede the flow of lubricant into the lateral and axial vent holes during non-operational vibration, such as shipping and handling of the end product. In another version, a plug is located in the lateral vent hole. The plug has a very small passage that permits air to pass therethrough for atmospheric pressure equalization, but prevents the escape of lubricant into the vent holes. Alternatively, the plug may be formed from a non-wettable material such as porous foam or sintered material and provided with a larger opening. Yet another solution utilizes a combination of both the labyrinth and plug designs.

Abstract: A lubricant retention design for a fluid dynamic bearing design in a spindle motor utilizes a labyrinth gap that is formed between the sleeve and the shaft of the bearing. The gap is used in conjunction with a barrier film to impede the flow of lubricant into the lateral and axial vent holes during non-operational vibration, such as shipping and handling of the end product. In another version, a plug is located in the lateral vent hole. The plug has a very small passage that permits air to pass therethrough for atmospheric pressure equalization, but prevents the escape of lubricant into the vent holes. Alternatively, the plug may be formed from a non-wettable material such as porous foam or sintered material and provided with a larger opening. Yet another solution utilizes a combination of both the labyrinth and plug designs.

Abstract: A lubricant retention design for a fluid dynamic bearing design in a spindle motor utilizes a labyrinth gap that is formed between the sleeve and the shaft of the bearing. The gap is used in conjunction with a barrier film to impede the flow of lubricant into the lateral and axial vent holes during non-operational vibration, such as shipping and handling of the end product. In another version, a plug is located in the lateral vent hole. The plug has a very small passage that permits air to pass therethrough for atmospheric pressure equalization, but prevents the escape of lubricant into the vent holes. Alternatively, the plug may be formed from a non-wettable material such as porous foam or sintered material and provided with a larger opening. Yet another solution utilizes a combination of both the labyrinth and plug designs.

Abstract: A motor control processor controls motor spin-up in a disk drive by detecting environmental temperature at the spindle motor of the disk drive, controlling commutation phase advance to generate substantially maximum torque if the detected environmental temperature indicates that maximum torque is needed, and adjusts the commutation phase advance for optimal efficiency after the maximum torque is no longer needed. Following motor start and reaching operational speed, the motor is operated in a steady-state maximum operating efficiency mode unless sensed environmental temperature indicates that maximum torque, rather than maximum efficiency, is needed. The system determines that the need for maximum torque has passed either when a predetermined time interval after motor start expires or by repeatedly polling motor temperature information.

Abstract: A spindle motor shaft having variable geometrical features for adjusting the torsion mode frequency of the shaft/stator assembly. The variable geometric features allow the torsion mode frequency to be tuned away from the driving force frequency of the motor. Variable geometrical features for the shaft may include circumferential grooves, radial slots cut through the shaft, or transverse holes disposed along the axis of the shaft. The radial slots have a longitudinal axis that is parallel to the axis of the shaft. Where circumferential grooves are used, the circumferential grooves may be designed to form a locator region along the shaft axis to promote axial alignment of the shaft and stator. Thermal track-misregistration (TMR) or screw torque problems are not introduced in the process of reducing or eliminating the acoustic problem thereby establishing a torsion mode frequency which is not subject to change due to temperature or time.

Abstract: A cartridge filter for an enclosed magnetic disk drive is disclosed which includes a dual media drum type filter element in a recirculating filter assembly that surrounds the breather filter and delivers air from the periphery of the disk stack to the axial entry of the ventilated disk spindle assembly. The cartridge provides an extended media surface within a compact space for frequent cycling of the enclosed air volume through the filter.