Abstract: A piezoelectric actuated suspension with passive damping is disclosed for precision positioning of hard disk drive while reducing undesired shock vibrations. Along the longitudinal axis of an etched suspension, two piezoelectric actuators dispose near the base plate to provide a push-pull motion. The actuators have two main portions. The first portion is piezoelectric elements to provide active positioning. The second portion is viscoelastic damping layers underneath the piezoelectric elements for passive damping. The complementary parts such as stiff edge elements and optional soft boundary covers are used to enhance the actuating abilities of the actuators and prevent any contaminants of the viscoelastic layers from going into the clean sealed chamber of the hard disk drive, respectively.

Abstract: Provided is an actuator, comprising a motor/generator element and a clutch/brake element. The motor/generator element comprises a stator made of a high magnetic permeable material, an outer coil being wound around the stator; a rotor made of a high magnetic permeable material and with a plurality of permanent magnets fixed thereon; and a cavity configured to receive a fluid. The clutch/brake element is arranged in the cavity. An inner coil is wound around the clutch/brake element. The fluid is capable of producing a shear stress in response to an electromagnetic field induced from the inner coil.

Abstract: A piezoelectric actuated suspension with passive damping is disclosed for precision positioning of hard disk drive while reducing undesired shock vibrations. Along the longitudinal axis of an etched suspension, two piezoelectric actuators dispose near the base plate to provide a push-pull motion. The actuators have two main portions. The first portion is piezoelectric elements to provide active positioning. The second portion is viscoelastic damping layers underneath the piezoelectric elements for passive damping. The complementary parts such as stiff edge elements and optional soft boundary covers are used to enhance the actuating abilities of the actuators and prevent any contaminants of the viscoelastic layers from going into the clean sealed chamber of the hard disk drive, respectively.

Abstract: A pick and place apparatus comprises a bond arm adapted for rotation about an axis between a pick location and a place location. The bond arm is formed with a cavity at an end of the arm remote from the axis, within which cavity are located a plurality of damping particles for damping unwanted vibrations of the bond arm. The particles may be irregular tungsten granules with a diameter between 0.3 and 1.2 mm and a filling ratio of about 75%.

Abstract: An active constrained layer system includes a passive viscoelastic damping material positioned on top of a substrate. An active piezoelectric layer is positioned on top of the passive viscoelastic damping material. An edge element physically connects the active piezoelectric layer to the substrate to transmit active forces and moments from the piezoelectric layer to the substrate. The novel edge element yields higher active control from the piezoelectric layer, while preserving the damping capacity of the passive viscoelastic layer. The edge element may be implemented in a variety of ways, including an edge element clamp structure and an edge element post structure.