G11B5/55

MAGNETIC TAPE DEVICE AND HEAD TRACKING SERVO METHOD

The magnetic tape device includes: a magnetic tape; and a servo head, in which a magnetic tape transportation speed of the magnetic tape device is equal to or lower than 18 m/sec, the servo head is a magnetic head including a tunnel magnetoresistance effect type element as a servo pattern reading element, the magnetic tape includes a non-magnetic support, and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, the magnetic layer includes a servo pattern, and a coefficient of friction measured regarding a base portion of a surface of the magnetic layer is equal to or smaller than 0.30.

Head suspension assembly having PZT damper

In a gimbal dual stage actuated (GSA) suspension for a disk drive, a viscoelastic damper is disposed between and adhered to the suspension's PZT microactuator and the flexure trace gimbal. The damper is dispensed in fluid form onto the trace gimbal during assembly of the suspension, the PZT is placed onto the damper, and the damper is then hardened leaving it adhered to both the PZT and the trace gimbal. The damper reduces peaks in the frequency response of the PZT actuation, thus allowing higher bandwidth of the servo control loop and increasing the effective read and write speeds for the suspension.

Behavioral model for dynamic tension compensation

A tape drive-implemented method, according to one embodiment, includes: detecting a read error, determining whether a current tension setting of the magnetic tape is accurate, determining whether the read error is part of an error burst in response to determining that the current tension setting of the magnetic tape is accurate, sending instructions to perform a first re-read attempt in response to determining that the read error is not part of an error burst, determining whether the first re-read attempt was performed successfully, selecting a range of tension settings in response to determining that the first re-read attempt was not performed successfully, selecting a range of lateral offsets, sending instructions to apply each unique combination of tension settings and lateral offsets, for each of the unique combinations applied, sending instructions to perform a second phase re-read attempt, and determining whether the second phase re-read attempt was performed successfully.

Disk drive having multiple disks accessible by a reduced number of read/write heads
10269380 · 2019-04-23 · ·

A disk drive including multiple magnetic recording disks and at least one read/write head, wherein the disk drive includes a rotatable center block having a vertical axis and a mounting member, a first motor attached to the center block for rotating the center block about the vertical axis, a vertical threaded rod positioned in the mounting member, a second motor moveable along the vertical threaded rod, at least one head suspension arm extending outwardly from the second motor, and at least one read/write head mounted to a distal end of one of the arms. The disk drive further includes multiple disks in a stack, wherein at least one of the arms is vertically moveable along the vertical threaded rod by the second motor to position the at least one read/write head in a position to access data on one of the disk surfaces of the plurality of disks.

Magnetic Recording Method
20190096435 · 2019-03-28 ·

A magnetic recording method, system and apparatus are described to increasing areal density capability (ADC) for a data storage system, where in different data tracks were written with different write configurations or with different writers in a particular way that is optimized to improve areal density for a data storage device. In an aspect, the data tracks were labeled as bottom, middle or top tracks, the write order follows in a particular way among different tracks, middle and top tracks partially trim the previously written track from one side. The distance between neighboring tracks, or the percentage of track trimmed, depend on the labels they have and the drive architecture used, are different. The particular write order can be in sequential or can have a certain level of randomness as set by the drive. The write order for each operation depend on the label determined by the drive for a given drive capacity requirement. For the apparatus to enable such approach, additional alignment condition between readers, writer, heater and temperature sensor are also optimized to improve performance, areal density and reliability.

Multi-layer PZT microactuator having a poled but inactive PZT constraining layer

A multi-layer piezoelectric microactuator assembly has at least one poled and active piezoelectric layer and one poled but inactive piezoelectric layer. The poled but inactive layer acts as a constraining layer in resisting expansion or contract of the first piezoelectric layer thereby reducing or eliminating bending of the assembly as installed in an environment, thereby increasing the effective stroke length of the assembly. Poling only a single layer would induce stresses into the device; hence, polling both piezoelectric layers even though only one layer will be active in use reduces stresses in the device and therefore increases reliability.

Magnetic disk device

According to one embodiment, a magnetic disk device comprises a JIT seek control unit, which uses second time series data of a current indication value of a VCM that sets a slope having an absolute value smaller than an absolute value of a slope of a first time series data in at least one of a monotonically decreasing interval of an acceleration interval and a monotonically decreasing interval of a deceleration interval of a head or an operation acceleration of the head.

Magnetic disk recording device having different time interval between first and second pre-heating periods
10229707 · 2019-03-12 · ·

A disk device includes first and second recording surfaces, a first head for the first recording surface, including a first heater which generates heat via a first electric power, a second head for the second recording surface, including a second heater which generates heat via a second electric power, and a control circuit configured to execute a first preheating operation in which the first electric power is supplied to the first heater for a first time interval prior to starting a first writing process to write data on the first recording surface by the first head, and to execute a second preheating operation in which the second electric power is supplied to the second heater for a second time interval prior to starting a second writing process to write data on the second recording surface by the second head. The first time interval is different from the second time interval.

Shortening the average reposition time to the beginning of files in a magnetic tape

A system accesses metadata on a file system of the magnetic tape, where the metadata comprising one or more fields enabling to determine a longitudinal position (LPOS) of one or more files located on the magnetic tape. The system determines the LPOS of the one or more files located on the magnetic tape. The system determines an optimal location of the head on the magnetic tape based on computing an average value to the determined LPOS of the one or more files located on the magnetic tape and moves the head on the magnetic tape to the optimal location.

Record head actuator sandwiched damper plus travel limiter

A magnetic recording head positioning assembly includes a coarse travel carriage secured to and spaced away from each of a front end assembly and head assembly via sandwiched fine guiding flexures and isolation flexures. The fine guiding flexures permit relative movement between the coarse travel carriage and head assembly. The isolation flexures permit relative movement between the coarse travel carriage and front end assembly. The fine guiding and isolation flexures thus isolate the coarse travel carriage from the front end assembly and head assembly. The assembly further includes dampers sandwiched between the coarse travel carriage and isolation flexures to limit movement of the isolation flexures.