G11B19/2009

Pressure-sensitive adhesive sheet and magnetic disc device

Provided is a PSA sheet that achieves both bonding reliability at a high temperature and reduction of outgassing. The PSA sheet provided by this invention comprises a substrate layer and a PSA layer provided to one face of the substrate layer. The PSA sheet exhibits a 180 peel strength of 1 N/20 mm or greater to stainless steel at 60 C. It has an amount of thermally released gas of 10 g/cm.sup.2 or less, determined at 130 C. for 30 minutes by GC-MS.

MTJ Device Performance by Adding Stress Modulation Layer to MTJ Device Structure
20200075844 · 2020-03-05 ·

A method for fabricating an improved magnetic tunneling junction (MTJ) structure is described. A bottom electrode is provided on a substrate. A MTJ stack is deposited on the bottom electrode. A top electrode is deposited on the MTJ stack. A first stress modulating layer is deposited between the bottom electrode and the MTJ stack, or a second stress modulating layer is deposited between the MTJ stack and the top electrode, or both a first stress modulating layer is deposited between the bottom electrode and the MTJ stack and a second stress modulating layer is deposited between the MTJ stack and the top electrode. The top electrode and MTJ stack are patterned and etched to form a MTJ device. The stress modulating layers reduce crystal growth defects and interfacial defects during annealing and improve the interface lattice epitaxy. This will improve device performance.

Motor drive device and motor system

An output control unit controls a drive terminal for a BEMF detection object phase to a high-impedance state in a mask term. A BEMF detection unit detects a voltage of the drive terminal for the detection object phase when a center tap voltage is set as a reference as BEMF in a PWM on-term for remaining two phases per PWM period in the mask term and asserts a zero-crossing signal when the voltage is reduced to zero. A PWM fixing unit fixes the remaining two phases to the PWM on-terms in a first term from a predetermined timing after an amplitude level of BEMF becomes smaller than a BEMF threshold amplitude to assertion of the zero-crossing signal. The BEMF detection unit continuously detects BEMF in the first term.

Systems and methods for reading phonographic record data
10553246 · 2020-02-04 ·

Systems and methods discussed herein are related to read data stored on phonographic records. In various examples, systems and methods may describe a needle assembly able to pivot with respect to a record player body, and include a gate able to block light transmitted from a light emitter. The record player may include a motor and a set of wheels such that it can travel around a stationary phonographic record, and a microcontroller capable of determining a target linear travel speed of the record player and receive and transmit data from the phonographic record.

Air-Bearing Surface (ABS) Design to Reduce Particle Scratch Risk
20200020355 · 2020-01-16 ·

A slider design for a hard disk drive (HDD) features a shallow cavity adjacent to a leading edge that has patterns of sub-cavities of various shapes etched into its base to reduce its original surface area. The presence of these patterns of sub-cavities significantly reduces the probability that the slider will capture particles on the surface of a rotating disk and thereby reduces the corresponding probability of surface scratches that such captured particles inevitably produce.

SPINDLE MOTOR
20200005826 · 2020-01-02 ·

A spindle motor according to one aspect of the present disclosure includes a shaft member, a baseplate having a through hole in which the shaft member is inserted and fixed, and a rotor member disposed on one side in an axial direction of the baseplate and rotatably supported through the shaft member. In a peripheral groove formed in an inner peripheral surface of the through hole, a gap between the shaft member and the baseplate is sealed by adhesive on the one side in the axial direction and the other side in the axial direction opposite to the one side, so that a confined volume of air is formed.

Hard disk drive multiple contact disk clamp

A disk clamp for a hard disk drive, configured to clamp disk media to a spindle, includes multiple protrusions extending from a surface of a bottom side and configured to contact a disk medium at multiple contact positions in response to application of a clamping load. The protrusions may be annular protrusions circumscribing a disk clamp hub, where the height of an inner protrusion may be less than the height of an outer protrusion to inhibit coning of the top disk medium, and the protrusions may be positioned so that an equivalent contact radius corresponding to contact radii of the inner and outer annular protrusions is at a position halfway between the inner and outer diameters of the disk spacers to inhibit coning of the middle disk media.

Spindle motor and hard disk drive device
11915720 · 2024-02-27 · ·

The spindle motor includes; a shaft including a shaft portion and a flange portion, the shaft portion having a columnar shape extending in an axial direction, the shaft portion including a shaft end portion, the flange portion being provided at the shaft end portion and receiving a load in the axial direction; and a bearing sleeve rotatably supporting the shaft, the bearing sleeve having a tubular shape including a sleeve end portion having a large-diameter recess part formed in the axial direction. The shaft is a member formed of a copper alloy containing from 0.5 mass percent to 1.5 mass percent of silicon and from 0.5 mass percent to 3.0 mass percent of manganese, and the member includes the shaft portion and the flange portion integrated with one another.

DISK DEVICE WITH WIRING BOARD ON OUTER SURFACE OF HOUSING AND CONNECTED TO MOTOR AND SEALING CONFIGURATION
20240055027 · 2024-02-15 ·

According to one embodiment, a disk device includes a housing with a bottom wall, magnetic disks supported on a hub of a motor, a printed circuit board provided on an outer surface of the bottom wall, and a wiring board attached on the outer surface of the bottom wall. The bottom wall includes a recess formed in the outer surface, a step located on border between the outer surface and the recess, and through holes opened to the recess. The wiring board includes one end portion disposed in the recess and connection pads on the one end portion, connected to lead wires of a coil. An adhesive is filled into the recess and the through holes, and covers the one end and a solder joint and seals the through holes.

BEARING DEVICE
20190368541 · 2019-12-05 ·

A bearing device includes an annular hub cap facing an inner ring. An inner annular surface of the hub cap abuts a part of one end surface of the inner ring which extends from an inner peripheral edge to an intermediate position located on the way from the inner peripheral edge to an outer peripheral edge. An annular adhesive retaining portion is formed between the area extending from the intermediate position to the outer peripheral edge of one end surface and at least an inclined annular surface of the hub cap.