Abstract: Methods and systems for detecting and correcting for undesirable vibrations impacting the servo systems in data storage devices. A detection technique is provided wherein a detection filter is configured to scan a position signal of the servo system across a range of frequencies, and, at each respective scanned frequency, record an amplitude associated therewith. The recorded amplitudes are examined to determine whether any exceed a threshold, thereby locating a peak frequency of the vibration. Using the detected peak frequency of the vibration, a corrective filter is configured to operate about the peak frequency of vibration, thereby reducing its impact on the position signal in the servo system.

Abstract: A disk drive system, includes a head, a controller for controlling an operation of the head, at least one feedback filter coupled in relation to the controller, and a mechanism for keeping a function of the at least one of the feedback filter active during any of an absence of a valid position error signal (PES) and a position error signal being unavailable due to a defect during an operation of the head.

Abstract: Methods and systems for detecting and correcting for undesirable vibrations impacting the servo systems in data storage devices. A detection technique is provided wherein a detection filter is configured to scan a position signal of the servo system across a range of frequencies, and, at each respective scanned frequency, record an amplitude associated therewith. The recorded amplitudes are examined to determine whether any exceed a threshold, thereby locating a peak frequency of the vibration. Using the detected peak frequency of the vibration, a corrective filter is configured to operate about the peak frequency of vibration, thereby reducing its impact on the position signal in the servo system.

Abstract: A method and system for reducing positioning noise in a data storage system are provided. An access device is positioned over a data storage medium using a stream of bursts stored on the medium. The bursts are sensed at a frequency determined by the rate at which the medium is moved relative to a sensing device. Output positioning values are provided to position the access device at a frequency higher than the frequency at which the positioning bursts are sensed, and/or at random times. The random times may be calculated as random advances or delays from time points occurring at a fixed frequency.

Abstract: A method and system for reducing positioning noise in a data storage system are provided. An access device is positioned over a data storage medium using a stream of bursts stored on the medium. The bursts are sensed at a frequency determined by the rate at which the medium is moved relative to a sensing device. Output positioning values are provided to position the access device at a frequency higher than the frequency at which the positioning bursts are sensed, and/or at random times. The random times may be calculated as random advances or delays from time points occurring at a fixed frequency.

Abstract: The present invention relates to an inertial latch mechanism of an actuator of a thin disk drive device. An inertial latch mechanism comprises a latch lever rotatable on a pivot from a release position to a latch position, and an inertial lever which is rotatable on a pivot and has a moment of inertia larger than that of the latch lever. The inertial lever rotates counterclockwise when a counterclockwise shock is given to the actuator, and pulls the latch lever at a first latch part by a first latch projection to move the latch lever to the latch position. The inertial lever also rotates clockwise when a clockwise shock is given to the actuator, and pushes the latch lever at a second latch part by a second latch projection to latch the actuator which has bumped against a crash stop and is reversely rotating.

Abstract: A disk drive system, includes an arm for mounting a head, and at least one component, coupled to the arm, for being synchronized to maintain a zero net angular momentum of the arm and the at least one component. Another disk drive system including a read/write head, includes a torque counter-generating member for being synchronized to maintain a zero net angular momentum of the head.

Abstract: A disk drive includes a data storage disk attached to a spindle which is rotatably mounted to a housing. A support shaft is also mounted to the housing parallel to the spindle, and includes an arm supported thereon parallel to the disk. A rib extends along the housing between the spindle and the support shaft for synchronizing fundamental resonant vibration thereof due to a shock load to couple in phase vibratory motion thereof. The support shaft may pivot and carry a suspension arm and data access head, or the shaft may be stationary and carry a load-unload ramp for parking the suspension arm, or both types of shafts may be used in the housing with corresponding ribs extending to the common spindle.

Abstract: In a direct access storage device including a rotating disk, a head positioned for interaction with said disk, an actuator for carrying said head and a servo system for operating said actuator so as to follow a substantially circular track on said disk by responding to a position error signal, a method for reducing response of the servo system to radial runout of the circular tracks, comprising the steps of obtaining radial runout data; filtering the data; storing the filtered data; subtracting the filtered data from the position error signal to obtain a corrected position error signal; and using the corrected position error signal to control the servo system.

Abstract: A miniature removable disk drive that meets the CompactFlash type II form factor and interface specifications uses a composite sheet metal/plastic tub-shaped base for supporting the disk drive components, e.g., the spindle motor with attached disk, the voice coil motor actuator with attached read/write head, and the preamplifier/write driver electronics module. The composite base is a metal plate with a flange extending around its perimeter and a plastic frame that encapsulates the flange and surrounds the perimeter of the metal plate. The metal plate supports the disk drive spindle motor and voice coil motor actuator and is made of high magnetic permeability, low coercivity material so that it can form part of the magnetic circuit of the spindle motor and/or actuator. The flanges on the metal plate provide rigidity and allow the base to be fabricated by injection molding the plastic frame onto the metal base so that the plastic encapsulates the metal flanges to form the walls of the tub-shaped base.

Abstract: A data storage device 12 includes a disk 14 having a surface zone 14a for storing data, and an access head 18 mounted on a slider 20 for writing data to and reading data from the data zone. The head 18 flies across the data zone 14a to access selected data tracks during spinning of the disk. And, the slider 20 seeks a predetermined shock buffer zone 30 atop the spinning disk, where critical data is not stored, during an idle mode for confining thereto any shock induced contact between the slider and disk surface.

Abstract: A disk drive with reduced seek acoustic noise and a method for implementation, without any additional hardware or mechanical modifications to the actuator includes a filter such that servo-loop stability is unaffected. The filter is inserted outside the existing servo loop to reshape the existing velocity profile in real time and to facilitate the suppression of forcing components that produce seek acoustics. A weighting factor may be used to provide a weighted average of the filtered and unfiltered velocity reference signal to the servo loop so that at the end of a track seek operation, the unfiltered reference signal is applied to the velocity servo, and there is almost no change in settle-out performance when the target track is reached. It is not necessary to store large volumes of velocity profile data to deal with different seek lengths.

Abstract: A technique for preventing damage to ball bearings in small form factor devices where the drive motor has at least one piezoelectric crash stop ring disposed about the shaft and inside the rotor of the motor. The crash stop ring must be dimensioned to permit only a small amount of movement of the rotor relative to the shaft. The permitted movement is less than the minimum movement which would cause damage to the elements of the ball bearing.

Abstract: A disk drive includes a data storage disk rotatably mounted in a housing. An access arm is rotatably mounted in the housing and has an access head at a distal end thereof for travel over the disk to write data thereto and read data therefrom. A pair of counter imbalanced inertia locks are operatively joined between the housing and the access arm for inertia latching the access arm upon shock loading of the access arm to prevent movement thereof over the disk irrespective of combinations of linear and angular shock loading.

Abstract: A method and system for overcoming force which inhibits movement of a data storage device are provided. The invention includes generating momentum in a moveable member and then utilizing the momentum of the moveable member to generate a large impulse force on a stationary body (e.g., the data storage device) to overcome the movement-inhibiting force thereon. This is accomplished by allowing the moveable member to move along a trajectory independently of the stationary body, thereby building momentum in the moveable member. The subsequent impact of the member on the body overcomes the force. The moveable member can then also be used, in one embodiment, to continue driving the body during system operation.

Abstract: In a direct access storage device having a head for interaction with a storage medium and a moving actuator on which the head is mounted, the improvement comprises a compound bearing system for the actuator, the bearing system including a first bearing of low friction for small movements of the actuator; and a second bearing of higher friction for coarse movements of the actuator. The storage medium is preferably a rotating magnetic disk having a series of concentric circular tracks. A single servo system drives the actuator so that the head follows a selected track with motion of the first bearing, and movement of the head to a new track causes motion of the second bearing. Preferably the first bearing is a flex bearing and the second bearing is a ball bearing.

Abstract: In a computer apparatus including an enclosure and a direct access storage device mounted within the enclosure, a mounting apparatus for the direct access storage device including: a plurality of a relatively rigid shock isolators and at least one stress sensor mounted in series with are of said shock isolators and disposed between the enclosure and the direct access storage device. The enclosure may include a user frame and the mounting apparatus may be disposed between the direct access storage device and the frame. There may be one stress sensor for each of the shock isolators. The shock isolators may be coupled to the direct access storage device. Each stress sensor may include a piezoelectric element. Preferably the shock isolators are rigid enough so that the resonant frequency of said mounting apparatus is at least 800 Hz, but can be 800 Hz or higher.

Abstract: When an HDD is subjected to shock with a magnetic head (22) retracted to the parking zone, a suspension (34) having a magnetic head (36) at the free end thereof swings. When a lowest suspension (34) swings, the free end of the suspension (34) is brought into contact with a pin projection (50) and further displacement toward the base (12) is impeded. The suspension (34) that further swings in this condition presents not a swing in a primary mode (cantilever support mode) but a swing in a secondary mode (two-point support mode), and the maximum displacement of the suspension (34) occurs at the longitudinal intermediate portion of the suspension (34). The intermediate portion that is displaced is made to go into a groove (48), and the contact of the intermediate portion of the suspension (34) with the base (12) is impeded by the groove (48).

Abstract: The present invention relates to a method and apparatus for writing servo tracks of a magnetic disk unit, and has an object of providing a servo track writing method and apparatus which can reduce a mechanical vibration of a head in the steady state and can shorten a settling time of the system. A detecting face is set in the vicinity of a head arm end portion 22 of a magnetic disk unit 2, and a capacitance probe 28 is provided as a gap detecting means for detecting a gap in a head moving direction between the detecting face and the head arm end portion 22. Further provided are a rotary positioner 26 as a positioning means for moving the capacitance probe 28 in the head moving direction to position it at a target position, and a head drive system control means for moving a head 14 of the magnetic disk unit 2 so that the gap is kept constant, to position the head 14 at a predetermined servo track writing position.

Abstract: A method and apparatus, in a direct access storage device including a head positioned for interaction with a data storage medium mounted on a rotating spindle, an actuator for positioning the head, and a servo control loop for positioning the actuator. The improvement comprises: a narrow band gain enhancing filter for connection in the servo control loop. The filter has a response frequency related to the rotational frequency of the spindle. The filter has programmable initial states. Also provided is a switch for switching in the narrow band filter as the head approaches a target position on the data storage medium. Initial states of the filter are determined and supplied to program the filter. At least one additional filter having a peak response frequency at a harmonic of the frequency of rotation of the spindle, may be provided. Initial states of the additional filters are determined and supplied to program the additional filter.