Various illustrative aspects are directed to a data storage device. The data storage device comprises a first actuator; a second actuator; a first set of disks, comprising one or more disks configured to correspond with the first actuator; a second set of disks, comprising one or more disks configured to correspond with the second actuator; and one or more processing devices. The one or more processing devices are configured to: write final spirals on the first set of disks; determine a time delta to implement cross-actuator alignment between the first set of disks and the second set of disks; and apply the time delta in writing final spirals for the second set of disks.

A gimbal assembly includes a frame having base, tip and mount portions, and a crossbar joined to the tip portion by a neck region. Portions of the crossbar and neck region define transition edge regions each extending from a point of minimum width D of the neck region to where the edge of the crossbar becomes substantially straight. Each of the transition edge regions includes a transition length a and a transition width b. The frame comprises an area of interest that includes the neck region and a portion of the crossbar that has a length of 0.6 mm and is centered to the neck region, and has a total area size A, a centroid C and a centroid distance H between the centroid C and a far side of the neck region. The crossbar and neck region have geometries that satisfy a design metric that is less than 0.05.

The invention has an object of providing grease reduced in an amount of the flying grease and an amount of the outgas, and superior in low-temperature characteristic, an antifriction bearing using the grease, an antifriction bearing device, and an information recording/reproducing device. A grease includes a base oil, and a thickener, the base oil includes mineral oil and poly-α-olefin, the poly-α-olefin is higher in mass than the mineral oil, the poly-α-olefin includes poly-α-olefin higher in kinetic viscosity than the mineral oil, the kinetic viscosity of the base oil at 40° C. is in a range of 40 through 90 mm.sup.2/s, and worked penetration is in a range of 200 through 250. Further, an antifriction bearing, an antifriction bearing device, and an information recording/reproducing device use the grease.

According to one embodiment, a disk device includes a plurality of recording media each including a recording layer and an actuator assembly including an actuator block rotatably supported around a rotation shaft, a plurality of arms extending from the actuator block, and suspension assemblies respectively attached to the arms and supporting respective magnetic heads. Of the plurality of arms, at least one arm has vibration characteristics different from those of the other arms.

A seek operation of a first actuator in a multi-actuator drive is modified, so that one or more disturbance-generating portions of the seek operation do not adversely affect operation of a second actuator in the drive. Radial motion of the aggressor actuator is controlled by limiting a slew rate of the first actuator during one or more portions of the seek operation to be less than or equal to a threshold value. Because slew rate of the first actuator is the rate of change of radial acceleration of the aggressor actuator with respect to time, limiting the slew rate of the first actuator prevents or reduces mechanical disturbances caused by jerk associated with motion of the first actuator.

According to one embodiment, a magnetic disk includes a disk, first and second heads which write data to the disk and read data from the disk, a first actuator includes the first head, a second actuator includes the second head, first and second controllers which control the first head, the second head, the first actuator and the second actuator, an auxiliary power supply which supplies power when power from a power supply is shut off, and a power supply detection unit which makes power supplied from the auxiliary power supply to the first controller higher than the power supplied from the auxiliary power supply to the second controller when shutoff of power from the power supply is detected.

A disk device includes one or more disks, a base shaft, a bearing shaft, first and second bearing units, first and second actuator assemblies, and a damping member. The bearing shaft has a tubular portion fixed around the base shaft. The first and second bearing units are attached around the bearing shaft and aligned in an axial direction of the bearing shaft. The first and second actuator assemblies are coupled to the first and second bearing units, respectively. The damping member is provided between an outer circumferential surface of the base shaft and an inner circumferential surface of the tubular portion of the bearing shaft.

According to one embodiment, a disk device includes a housing including a base with a bottom wall, a drive motor including a pivot erected on the bottom wall and a hub rotatably supported around the pivot, ten or more magnetic disks attached to the hub and stacked on a flange of the hub, and spacer rings attached to the hub and each disposed between each respective adjacent pair of two magnetic disks. A number of the spacer rings is one less than the magnetic disks. At least one spacer ring has a thickness different from that of the other spacer rings, and a difference between a maximum thickness and a minimum thickness of the spacer rings is 0.01 mm or more and 0.09 mm or less.

A tolerance ring having a first axial end, a second axial end, and a central axis, the tolerance ring including an annular band; a plurality of protrusions, all of the plurality of protrusions extending from the annular band; and a guide portion extending from the annular band towards the first axial end of the tolerance ring, where the guide portion includes a guide surface that is curved in an axial section.

A motor includes a rotor, a stator, a shaft, a base part, a hole part, a connector, and a metal connection portion. The rotor is rotatable about the axial direction. The stator radially opposes the rotor. The shaft extends axially along the central axis and supports the rotor. The base part is disposed on axial one side relative to the stator, and radially expands from the shaft. The hole part axially penetrates the base part. The connector covers the hole part when viewed from the axial direction. The metal connection portion connects the connector to the base part. The metal connection portion is disposed between the base part and the connector in the axial direction, and surrounds the hole part when viewed from the axial direction.