A piezoelectric element includes a substrate, a lower electrode arranged on the substrate, a piezoelectric film arranged on the lower electrode, and an upper electrode arranged on the piezoelectric film. Membrane portions are configured by the lower electrode, the piezoelectric film, and the upper electrode, and supported in a cantilever manner on the substrate, due to a recess formed in the substrate and a through hole penetrating the lower electrode, the piezoelectric film, and the upper electrode. At least two of the membrane portions have resonance frequencies different from each other.

A device for varying a pedal resistance of a hydraulic brake system includes at least one electroactive polymer actuator. The device further includes a reaction disc. The reaction disc has at least two polymer actuators. The at least two polymer actuators are independently controllable. Additionally, the at least two polymer actuators are arranged coaxially relative to one another.

This invention describes a method for producing highly controllable motion in electroactive materials and electroactive actuators capable of pronounced contraction and expansion, which act as synthetic muscle, tendon, fascia, perimysium, epimysium, and skin that wrinkles, comprising ion-containing, cross-linked electroactive material(s); solvent(s); electrode(s); attachments to levers or other objects; and coating(s). Restriction of movement in undesired direction(s) produces pronounced movement in the desired direction(s). The electroactive material itself or the electroactive actuator may be used individually or grouped to produce movement when activated by electricity. This invention can provide for human-like motion, durability, toughness, speed, and strength. The electroactive materials and electroactive actuators, with highly controllable motion, can be attached to objects and devices to produce motion with no metal pulleys, gears, or motors needed.

A solid-state device includes a substrate with a stack of constituent thin-film layers that define an arrangement of electrodes and intervening layers. The constituent layers can conform to or follow a non-planar surface of the substrate, thereby providing a 3-D non-planar geometry to the stack. Fabrication employs a common shadow mask moved between lateral positions offset from each other to sequentially form at least some of the layers in the stack, whereby layers with a similar function (e.g., anode, cathode, etc.) can be electrically connected together at respective edge regions. Wiring layers can be coupled to the edge regions for making electrical connection to the respective subset of layers, thereby simplifying the fabrication process. By appropriate selection and deposition of the constituent layers, the multi-layer device can be configured as an energy storage device, an electro-optic device, a sensing device, or any other solid-state device.

A driver includes a piezoelectric sheet, a fixing frame, a moving frame, and a control circuit. The piezoelectric sheet includes a first piezoelectric body portion which bends in a first direction, a second piezoelectric body portion which bends in a second direction that intersects at right angles with the first direction, and a connection portion which connects the first and second piezoelectric body portions. The fixing frame is fixed to the connection portion. The moving frame is supported on the first and second piezoelectric body portions. The control circuit applies voltage signals to the first and second piezoelectric body portions to bend the first and second piezoelectric body portions and which moves the moving frame in one of the first direction and the second direction or in a composite direction of the first direction and the second direction.

A multi-layer piezoelectric element includes: a stacked body comprising an active section, and inactive sections disposed at opposite ends in a stacking direction of the active section; an electrically-conductive bonding material disposed on a side surface of the stacked body from the active section to the inactive sections; and an external electrode plate attached, through the electrically-conductive bonding material, to the side surface of the stacked body, a spacing between a side surface of at least one of the inactive sections and the external electrode plate being wider than a spacing between a side surface of the active section and the external electrode plate, and the electrically-conductive bonding material situated between the side surface of at least one of the inactive sections and the external electrode plate being larger in thickness than the electrically-conductive bonding material situated between the side surface of the active section and the external electrode plate.

There is provided a piezoelectric element in which dielectric breakdown or breakage is less prone to occur even in long term use at a high voltage; and an acoustic generator, an acoustic generation device, and an electronic apparatus employing the same. A piezoelectric element includes: a stacked body in which a plurality of internal electrodes and piezoelectric layers are laminated, the stacked body having a rectangular shape in a plan view thereof; and a plurality of connecting electrodes connected to one ends of the plurality of internal electrodes, respectively, corner portions of the other ends of the plurality of internal electrodes being chamfered.

In one general aspect, various embodiments are directed to an ultrasonic surgical instrument that comprises a transducer configured to produce vibrations along a longitudinal axis at a predetermined frequency. In various embodiments, an ultrasonic blade extends along the longitudinal axis and is coupled to the transducer. In various embodiments, the ultrasonic blade includes a body having a proximal end and a distal end, wherein the distal end is movable relative to the longitudinal axis by the vibrations produced by the transducer.

A film transducer has a holding part and an electroactive multilayer composite structure including at least two deformable carriers which are each coated on at least one side with a planar electrode. The multilayer composite structure has an elongated basic shape and being clamped on its shorter sides in a fixing section in the holding part while its longer sides are free, the electrodes of the multilayer composite structure being alternately connected at the ends clamped in the holding part to a contact element which is arranged in the fixing section.

A button device includes a piezoelectric element which includes a piezoelectric body with one surface on which a first external electrode and a second external electrode are formed and a plate with one surface attached to the other surface of the piezoelectric body, a supporting plate disposed on the one surface of the piezoelectric body, a cover disposed on the other surface of the plate, a first spacer provided between an edge portion of the one surface of the plate and the supporting plate, a second spacer provided between at least a part of an edge portion of the other surface of the plate and the cover to provide a separation space between the plate and the cover, and a dot provided in the separation space to transfer an external force to the piezoelectric element or to transfer a vibration of the piezoelectric element to the cover.