According to one embodiment, a wiring board unit includes a reinforcing board, a flexible printed circuit board includes a joint portion including a first plane and a second plane and attached on the reinforcing board, a relay unit extending from the first plane, a plurality of connection pad groups located on one of the first plane and the second plane and a first IC chip mounted on the first plane, and the joint portion is bent on a boundary between the first plane and the second plane.

An insulation resistance measurement device includes a jig unit, a control unit and a transfer mechanism. The jig unit includes a lower jig having a reference surface, an upper jig having an abutting surface, a probe unit and a servomotor. When the upper jig is lowered toward the lower jig by the servomotor, the probe contacts a portion to be measured. When the upper jig is lowered further and the abutting surface of the upper jig abuts the reference surface, a torque of the servomotor increases. When the torque reaches a predetermined value, an insulation resistance is measured by the probe in a state where the torque is maintained.

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 calibration standard for calibrating a tool for measuring the surface energy of a data storage component is prepared by providing a standardized sized, dimensionally stable bead having a diameter selected from a length of from 1 to 100 m and depositing the bead on a surface of a substrate and adhering the bead to the surface with an adhesive. The calibration standard made by these processes is also contemplated.

A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.

A tolerance ring has a hollow band with outwardly extending corrugated protrusions forming waves that engage an inner surface of a bore of a housing. At one end of the tolerance ring is an inwardly flared guide surface extending axially and radially from the band. The guide surface acts as a tapered entrance to assist the insertion of a shaft into the hollow band during assembly of the ring into the bore of the housing.

According to one embodiment, an electronic device includes a housing, a substrate, a connector, a metal member, a screw, first solder, and second solder. The substrate includes a first surface to which a second hole opens and a metal region to which a first hole opens. The region is provided on the first surface. The connector is provided with a third hole. The metal member is attached to the connector and includes a second surface to which a fourth hole opens and a joint inserted into the second hole. The screw attaches the connector and the metal member to the housing through the third hole and the fourth hole. The first solder joins the region and the second surface to each other. The second solder joins an inner surface of the second hole and the joint to each other.

A tri-stage actuated disk drive suspension is described. The tri-stage actuated disk drive suspension including a beam and a gimbal attached to the beam. The gimbal is configured to receive a first actuator to mount on a first surface of the suspension near a first lateral side of the suspension and is configured to receive a second actuator to mount on the first surface of the gimbal near a second lateral side of the suspension. The gimbal is configured to receive a head slider to mount on the first surface of the suspension. And, the tri-stage actuated disk drive suspension including a baseplate having the beam attached thereto. The baseplate configured to receive a third actuator from the first surface of the suspension to mount on a pair of shelves.

A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.

A PZT microactuator such as for a hard disk drive has a restraining layer bonded on its side that is opposite the side on which the PZT is mounted. The restraining layer comprises a stiff and resilient material such as stainless steel. The restraining layer can cover most or all of the top of the PZT, with an electrical connection being made to the PZT where it is not covered by the restraining layer. The restraining layer reduces bending of the PZT as mounted and hence increases effective stroke length, or reverses the sign of the bending which increases the effective stroke length of the PZT even further. The restraining layer can be one or more active layers of PZT material that act in the opposite direction as the main PZT layer. The restraining layer(s) may be thinner than the main PZT layer.