G11B5/55

Magnetic disk device and method

According to an embodiment, a magnetic disk device includes a magnetic disk, a magnetic head, and a control circuit. The magnetic disk has a plurality of first storage regions disposed in the radial direction. The recording method is changeable for each of the plurality of first storage regions. The control circuit operates such that, when having received a first command instructing to change the recording method of one first storage region out of a plurality of first storage regions, the control circuit changes the recording method of the one first storage region in accordance with the first command, and moves a magnetic head onto the second storage region before receiving a second command.

Magnetic disk device with enhanced control of write processing based on a shift in drift of level (DOL)

According to one embodiment, a magnetic disk device includes a disk, a head configured to write data to the disk and read the data from the disk, and a controller configured to control write processing based on a first determination value corresponding to a first shift amount defined for the excessive number of times at which the first shift amount of the head in a radial direction of the disk exceeds a first threshold value causing a read error in a second track adjacent to a first track in the radial direction at a time of the write processing of the first track of the disk, and a second threshold value changing the write processing.

Center structure having attachment support for an actuator in a multi-actuator hard disk drive

A multi-actuator hard disk drive includes a lower actuator with a corresponding voice coil motor assembly (VCMA), a coaxial upper actuator with a corresponding VCMA, and a central support plate positioned between the upper and lower VCMAs and to which the upper VCMA is fastened. Use of a central support plate enables some control over the direct and coupled plant transfer functions, while effectively providing a base support structure for the upper VCMA and enabling use of conventionally-sized fasteners.

Data storage device with write caching for maximizing disk access during laser diode steady state

Various illustrative aspects are directed to a data storage device, method, and one or more processing devices that are configured to: maintain respective measures of write commands associated with respective ones of shingled magnetic recording (SMR) zones defined in a data storage device, wherein data associated with the write commands is stored in a write cache associated with the data storage device; select one of the SMR zones based on the respective measures; perform a pre-heat operation of a laser diode included in a head associated with the selected one of the SMR zones; and perform a continuous write operation in the selected one of the SMR zones following the pre-heat operation, wherein the continuous write operation writes at least a portion of data stored in the write cache associated with the selected one of the SMR zones.

Head velocity derating for data storage devices including disk media

A Data Storage Device (DSD) includes a disk to store data, at least one head to read and write data on the disk, and a Voice Coil Motor (VCM) to move the at least one head over the disk. An upper velocity limit is reduced for moving the at least one head to perform a command to read or write data at a target location on the disk as a precautionary measure against damaging the at least one head during an Emergency Power Off (EPO) state. The upper velocity limit is reduced in response to the target location being in an Outer Diameter (OD) region of the disk, a direction needed to move the at least one head being in an Inner Diameter (ID) to OD direction, and a starting position being at least as radially far from an OD region position as a predetermined threshold.

Head velocity derating for data storage devices including disk media

A Data Storage Device (DSD) includes a disk to store data, at least one head to read and write data on the disk, and a Voice Coil Motor (VCM) to move the at least one head over the disk. An upper velocity limit is reduced for moving the at least one head to perform a command to read or write data at a target location on the disk as a precautionary measure against damaging the at least one head during an Emergency Power Off (EPO) state. The upper velocity limit is reduced in response to the target location being in an Outer Diameter (OD) region of the disk, a direction needed to move the at least one head being in an Inner Diameter (ID) to OD direction, and a starting position being at least as radially far from an OD region position as a predetermined threshold.

Integrated recording head with selective movement
09659594 · 2017-05-23 · ·

In one example, a head is provided that may include a slider body, a transducer body, a transducer connected to the transducer body, and an interleaver assembly interconnecting the slider body and the transducer body. The interleaver assembly may include an interleaver body to which the transducer body is attached, the interleaver body having a plurality of geometric features that enable temporary deformation of the interleaver body in response to exertion of a force on the interleaver body, and the interleaver body may further include piezoelectric elements positioned in the interleaver body, the piezoelectric elements operable such that, when selectively actuated, the piezoelectric elements exert a force on the interleaver body so as to effect selective movement of the transducer with respect to a surface of a medium.

Enlarged substrate for magnetic recording medium

A data storage device having a housing member for a selected one of a 3 inch form factor hard disc drive (HDD) or a 2 inch form factor HDD. A spindle motor coupled to the housing member supports a rotatable data recording disc with a plurality of data tracks and an outermost perimeter. The outermost perimeter has an average overall radius of 48.5 millimeters, mm responsive to the housing member being for a 3 inch form factor HDD or an average overall radius of 33.5 mm responsive to the housing member being for a 2 inch form factor HDD. The rotatable data recording disc further has an outermost data track at an average selected radius such that the difference between the average overall radius of the outermost perimeter and the average selected radius is more than 1 mm.

Co-located gimbal-based DSA disk drive suspension with traces routed around slider pad

A suspension having a DSA structure on a gimbaled flexure includes a loadbeam and a flexure attached to the loadbeam. The flexure includes a metal layer with a pair of spring arms, a tongue including a slider mounting surface, and a pair of struts connecting the pair of spring arms to the tongue. The suspension further includes a pair of traces including one or more insulated conductors and being routed around opposite sides of the slider mounting surface, over the pair of struts to a set of terminal contacts on a distal portion of the tongue. The suspension also includes a motor mounted on the flexure, the motor having opposite lateral ends, the motor orientated laterally across the flexure such that the opposite lateral ends of the motor are on opposite lateral sides of the flexure. Electrical activation of the motor rotates the slider mounting surface relative to the loadbeam.

Bearing device
09640207 · 2017-05-02 · ·

In order to prevent leaking of lubricant, the bearing device includes a rolling bearing having an outer ring and an inner ring, a shaft fixed to the inner ring, and a sleeve fixed to the outer ring. A flange part is formed on at least one end part of the shaft. The flange part includes a disk part extending from the shaft toward an outside in a radial direction and a cylindrical part extending from the disk part along an axial direction. The cylindrical part is disposed at an outside of the outer ring, and a labyrinth gap which bends at two places is formed by gaps.