Abstract: A novel tolerance ring includes a hollow cylindrical body defining a longitudinal axis that passes axially through its center. A circumferential gap divides the hollow cylindrical body so that the hollow cylindrical body includes first and second longitudinal edges that define the circumferential gap. A plurality of bumps protrude radially from the hollow cylindrical body, and consists of a plurality of gap-adjacent bumps and a plurality of non-gap-adjacent bumps. At least one of the plurality of bumps is circumferentially between the gap and each of the non-gap-adjacent bumps. None of the plurality of bumps is circumferentially between the gap and each of the gap-adjacent bumps. The tolerance ring includes a means for increasing an otherwise lower average radial compressive stiffness of the gap-adjacent bumps to become substantially equal to an average radial stiffness of the non-gap-adjacent bumps.

Abstract: A tolerance ring configured to improve mass eccentricity of an actuator arm assembly. The tolerance ring has a cylinder with a predetermined length between two ends, with a gap along the predetermined length of the cylinder, the gap having a first and a second edge, the cylinder having an aperture in the surface of the cylinder at the second edge.

Abstract: A damper for a data storage device having a viscoelastic material and a constraint material disposed on the viscoelastic material, the constraint material covers the sides of the viscoelastic material to reduce exposure of the viscoelastic material from debris in the surrounding environment.

Abstract: A tolerance ring configured to prevent interlocking during shipping and handling. The tolerance ring has a cylinder with a first radius about an axis of rotation and a gap in the cylinder surface having a first edge and second edge extending along the axis. The gap in the cylindrical base has a first tab on the first edge and a second tab on the second edge. The first tab is adapted for coupling to the second tab and thereby prevents the interlocking of one tolerance ring with another. The gap can be configured to be non-linear.

Abstract: Transducer suspensions are attached to actuator arms by means of bonding a portion of a thermoplastic actuator arm to the magnetic recording head suspension assembly. The actuator arm has rail portions that provide a channel in which the load beam and base plate flange fit. The rail portions are ultrasonically welded using a clamping ultrasonic horn, which causes melted plastic to flow over the flange The clamping ultrasonic horn causes heat to be applied and focused at prongs to cause the rails to flow and expand onto the flange rigidly connecting the base plate and load beam to the actuator arm.

Abstract: A method of bonding a magnetic disk drive head suspension to an actuator arm. The actuator arm has a boss hole therein and the suspension includes a base plate with an inside diameter or barrel therein. A thermoplastic cylindrical core is fabricated with a barrel therein. The suspension and actuator arm are clamped together to form a head stack assembly in which the base plate inside diameter is aligned with the boss hole in the actuator arm. The thermoplastic cylindrical core is passed through the base plate inside diameter and the boss hole in the actuator arm. A heating tool, such as an ultrasonic horn is passed through the barrel of the cylindrical core and heated causing the cylindrical core expand and bond to the base plate inside diameter and to the actuator arm boss hole.

Abstract: A method of and apparatus for assembling a disk drive. The method comprises steps of clamping a number of head suspension assemblies in an actuator body such that base plate hubs in the suspensions are in alignment with corresponding boss holes in actuator arms extending from the actuator body, inserting closed jaws between the actuator arms and in alignment with the base plates, and opening the jaws a reach sufficient to urge each base plate hub into a corresponding boss hole. The jaws are opened by any suitable mechanism, for example by driving a wedge in between the closed jaws. A novel apparatus is employed for joining base plate hubs to actuator arms extending from an actuator body. The apparatus includes an actuator body clamp adapted to hold a number of suspensions in the actuator body, with hubs of the suspensions in alignment with boss holes in the actuator arms.

Abstract: A method of attaching a load beam to a head actuator arm. A number of weld holes are provided in the load beam and the actuator arm. A thermoplastic base plate is aligned over the weld holes in the load beam and the actuator arm. A heating tool having a number of pins is clamped over the base plate such that points of the heating tool pins coincide with the number of weld holes. The heating tool is heated such that peaks of thermoplastic base plate material are extruded through the weld holes. The heating tool causes heat to be applied and focused at the points to cause the thermoplastic base plate to flow and expand into the weld holes in both the load beam and the actuator arm, thereby rigidly connecting the thermoplastic base plate and load beam to the actuator arm.

Abstract: Laminates consisting of a high-damping core material sandwiched between two stiff, weldable skins. The laminate structures have increased resonant freguencies, improved damping characteristics, do not outgas, and may have a decreased inertial moment. The laminates are comprised of 100% metal constituents, and do not rely on epoxy or low-melting point solders.

Abstract: A base plate for a suspension assembly in a hard disk drive wherein the base plate has a hardened flange and soft hub. The base plate is stamped in a progressive die in a sequence of forging and coining operations. The base plate is subsequently fully annealed to allow the material to yield at a low stress level so that the hub will create a press fit against the inner wall of an actuator arm boss hole. The base plate is passed through a secondary coining operation following the annealing step to work-harden the flange portion only. The result is a base plate with a flange portion that is hardened and a hub portion that is softer than the flange portion. The advantage is that the hardened flange is more resistant to deformation of a load beam welded thereto and the hub is more disposed to plastically deform and harden during swaging which is desirable for maintaining a press fit.

Abstract: An apparatus for measuring the reliability of a swage mount interconnecting components of a workpiece using a computer-controlled apparatus. The apparatus includes a mechanism that connects the components by a swaging process under precisely controlled conditions and a mechanism to subsequently cause the swaged connection to fail under controlled conditions. A computer-controlled power twist mechanism applies known, controlled torques to the swaged test components. A laser beam detection system is used to monitor any displacement of the test components as the torque is applied.