An electrical connection structure for connecting a piezoelectric element and an electrical circuit to each other with a conductive adhesive is described. The electrical connection structure includes an epoxy, a conductive component surrounded by the epoxy, and a trace feature implemented on top of the electrical connection structure.

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.

According to one embodiment, a disk device includes a recording medium, electronic components including a magnetic head, a flexure, and an adhesive. The flexure includes a surface on which the electronic component is mounted, a first wiring and a second wiring each extending along the surface, and a groove provided on the surface between the first/second wirings. The adhesive is in contact with an inner surface of the groove and includes an adhesive portion attaching the electronic component to the surface. A first portion in the flexure is provided in a position apart from the electronic component. A second portion in the flexure is positioned closer to the adhesive portion than the first portion. A distance between the first wiring and the second wiring is larger than that in the first portion.

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.

According to one embodiment, a suspension assembly includes a support plate, a trace member on the support plate and a drive element mounted on the trace member. The trace member includes a metal plate, and a multilayered member on the metal plate. The multilayered member includes a first insulating layer, a conductive layer stacked on the first insulating layer, a second insulating layer stacked on the conductive layer. The multilayered member includes a mount portion on which the drive element is mounted, and a branching portion arranged along the mount portion with a gap therebetween. At least one portion of the branching portion is formed into a thin portion having a thickness less than other portions of the multilayered member.

According to one embodiment, a head suspension assembly includes a support plate, a wiring member on the support plate, a head, and a piezoelectric element on the wiring member. The wiring member includes a metal plate and a multilayered member including a first insulating layer, a conducting layer, a second insulating layer, and connection pads formed from the conducting layer. Each of the connection pads is overlaid on a recess formed in the first insulating layer, so as to form a recessed portion along the recess, and the second insulating layer includes an opening opposing each of the connection pads. The piezoelectric element is connected to the connection pads by a conductive adhesive filled in the openings and the recessed portions of the connection pads.

A driving circuit is described. The driving circuit includes: a first piezoelectric actuator including at least one piezoelectric element disposed between a first electrode and a second electrode, the first electrode configured to connected to a first ground at a first terminal and the second electrode configured to connected to an amplifier at a second terminal. The driving circuit includes a second piezoelectric actuator including at least one piezoelectric element disposed between a first electrode and a second electrode, the first electrode configured to connected to a control signal at a first terminal and the second electrode connected to a second ground at a second terminal. And, the first terminal of the first piezoelectric actuator and the first terminal of the second piezoelectric actuator are configured such that the first piezoelectric actuator and the second piezoelectric actuator are symmetrical and have similar polarity.

Examples of a suspension are provided. The suspension includes a mount plate attached to a load beam at a suspension assembly attachment point. The suspension may include a first actuator and a second actuator located at the mount plate. The first actuator is shaped as a non-right angle parallelogram spanning across a first opening in the mount plate. The second actuator is shaped as a non-right angle parallelogram spanning across a second opening in the mount plate. The first and second actuators are configured to deflect the distal end of the mount plate, which causes the load beam to rotate with a rotation center located along the load beam.

A method of manufacturing a piezoelectric microactuator having a wrap-around electrode includes forming a piezoelectric element having a large central electrode on a top face, and having a wrap-around electrode that includes the bottom face, two opposing ends of the device, and two opposing end portions of the top face. The device is then cut through the middle, separating the device into two separate piezoelectric microactuators each having a wrap-around electrode.

A multi-layer piezoelectric microactuator assembly has at least one poled and active piezoelectric layer and one poled but inactive piezoelectric layer. The poled but inactive layer acts as a constraining layer in resisting expansion or contract of the first piezoelectric layer thereby reducing or eliminating bending of the assembly as installed in an environment, thereby increasing the effective stroke length of the assembly. Poling only a single layer would induce stresses into the device; hence, polling both piezoelectric layers even though only one layer will be active in use reduces stresses in the device and therefore increases reliability.