Abstract: A multidomain plate acoustic wave device is provided having one or more single piezoelectric crystalline plates with differently polarized ferroelectric domains, where the domains have diverse directions of their axes of polarization. The device may consist of a multidomain plate acoustic wave transducer, a multidomain plate acoustic wave delay line, a multidomain plate acoustic wave rf filter, and any combination thereof. The differently polarized ferroelectric domains may comprise a collection of inversely or differently poled ferroelectric domains within a single piezoelectric medium. The medium may be any crystalline or ceramic plate with non-zero piezoelectric properties, in which the domains are created and embedded. In varying embodiments, the device includes electrodes oriented to generate an external rf field in various, respective directions, including in a direction normal to a basal plane of the device, or in a direction parallel to a length or a width of the device.

Abstract: The invention relates to an ultrasonic motor having a multilayer actuator in the form of a multilayer plate, having one or more friction elements or friction layers on its side surfaces and having an electrical exciter apparatus for the actuator. According to the invention, the multilayer plate has two intersecting, mirror-imaged asymmetrical generators for ultrasonic vibrations, to be precise in the form of layers of exciter electrodes and general electrodes which are alternately arranged with layers of piezoelectric ceramic, wherein a two-dimensional asymmetrical acoustic standing wave is generated in the multilayer actuator.

Abstract: A vibration wave driving device comprises a vibrator having an electromechanical conversion device, a supporting member for supporting the vibrator, and a driven member brought into contact with a part of the vibrator driven frictionally by vibration excited in the vibrator: the supporting member comprising a vibration portion vibrating together with the vibrator, a fixation portion for fixing the supporting member, and a support portion for connecting the vibration portion with the fixation portion and supporting the vibrator; and the support portion being comprised of a laminate of sheets.

Abstract: A physical shield placed on the face of a high intensity focused ultrasound transducer for medical applications is described. The shield may be shaped or angled to match a particular pattern of mechanical or acoustic energy that may damage the transducer during operation. The shield may be ablative, replaceable or modified as needed. Methods of manufacturing a transducer with a shield are also disclosed.

Abstract: A piezoelectric power generator that performs conversion between kinetic energy and electrical energy. The piezoelectric power generator is equipped with a beam, a piezoelectric element and a flexible body. The piezoelectric element is bonded to a surface on one side of the beam. The flexible body is arranged on a side of the beam that is opposite to that on which the piezoelectric element is provided. A portion of the beam is connected to the flexible body. The beam is configured such that stress is applied to the beam when the flexible body is deformed into a concave shape with respect to the beam, whereas a stress is not applied to the beam when the flexible body is deformed into a convex shape with respect to the beam.

Abstract: An inverter is capable of converting a direct current from a direct current power supply into an alternating current and supplying it to an armature winding. A rectifier circuit is capable of rectifying the current, that has been converted to an alternating current by the inverter, into a direct current and supplying it to the field winding. The amount of the alternating current supplied to the armature winding and the amount of the direct current supplied to the field winding are in a proportional relationship, and implementation of switching control of the inverter controls both the amount of the alternating current supplied to the armature winding and the amount of the direct current supplied to the field winding while this proportional relationship therebetween is maintained.

Abstract: A method for tuning a resonant frequency of a piezoelectric component is disclosed. The piezoelectric component includes a transducer extending in three spatial directions. The resonant frequency depends on an extension in at least one of the spatial directions and/or on a material-dependent elasticity modulus. The transducer includes a layered structure with at least two first electrodes and at least one second electrode, which is disposed between the two first electrodes. In the method, a DC voltage is applied to at least one of the at least two first electrodes and the at least one second electrode, so that a change of the resonant frequency results due to a change to the extension in the one spatial direction and the elasticity modulus. A control voltage with an excitation frequency is applied, the excitation frequency substantially corresponding to the modified resonant frequency. This generates a vibration of the piezoelectric component.

Abstract: Provided is a small piezoelectric power generator applied to a wireless sensor network system of a tire pressure monitoring system (TPMS) for monitoring an internal environment of a tire such as variation in air pressure in the tire. In particular, when the system, in which air pressure, temperature and acceleration sensors are mounted, installed in the tire is operated in the TPMS for an automobile, a small piezoelectric power generator for the TPMS can be used as a power source in place of a conventional battery. The piezoelectric power generator includes a substrate having an electrode for transmitting power to the exterior, a metal plate formed on the substrate, and a piezoelectric body disposed on the metal plate and transmitting the power generated by a piezoelectric material to the electrode.

Abstract: Piezo-electric actuator 50 of the present invention comprises piezo-electric element 10 for performing expansion/contraction motions in accordance with an electric field condition, seat 20 to which piezo-electric element 10 is adhered on at least one surface thereof, and supporting member 45 for supporting piezo-electric element 10 and seat 20, wherein piezo-electric element 10 and seat 20 vibrate up and down in accordance with the expansion/contraction motions of piezo-electric element 10. Seat 20 is connected to supporting member 45 through vibration 30 film which is less rigid than this seat 20.

Abstract: Electroactive polymer transducers for sensory feedback applications are disclosed.

Abstract: A drive device includes a stator; a rotatably provided drive member; a piezoelectric element, which is nipped between the stator and the drive member in a tangential line direction of a rotation locus circle of the drive member, and expands and contracts in the tangential line direction at an expansion speed at the time of the expansion and a contraction speed at the time of the contraction, respectively, the expansion speed and the contraction speed different from each other; and a rotor provided concentrically with the drive member to touch the drive member with a pressure.

Abstract: The present invention provides devices and structures and methods of use thereof in electrochemical actuation. This invention provides electrochemical actuators, which are based, inter-alia, on an electric field-driven intercalation or alloying of high-modulus inorganic compounds, which can produce large and reversible volume changes, providing high actuation energy density, high actuation authority and large free strain.

Abstract: Acoustic resonator comprising an electret, and method of producing said resonator, application to switchable coupled resonator filters. The resonator comprises: at least one piezoelectric layer (30); electrodes (24, 26) on either side of this layer; and at least one electret layer (32) between the electrodes, to apply a permanent electric field to the piezoelectric layer. The intensity of this electric field is determined to shift the resonance frequency of the resonator by a desired value. The piezoelectric layer may contain electrical charges to itself constitute the electret layer.

Abstract: Compositions and devices for harvesting electrical energy from mechanical and thermal energy, storing such produced energy, and sensing strain based on low cost materials and processes. In embodiments, the compositions are flexible and include a flexible polymer embedded and coated with a nanostructured piezoelectric material.

Abstract: A control device that includes an AC voltage command determination section that determines an AC voltage command value, which is a command value of the AC voltage supplied from the DC/AC conversion section to the AC electric motor, on the basis of a target torque of the AC electric motor and a rotational speed of the AC electric motor; and a system voltage command determination section that determines a system voltage command value, which is a command value of the system voltage generated by the voltage conversion section, on the basis of the AC voltage command value and the system voltage.

Abstract: A surface acoustic wave device includes a piezoelectric substrate including an R-plane, a-plane, or m-plane sapphire substrate and a LiNbO3 film of (90°, 90°, ?15° to 15°) or (0°, 90°, ?15° to 15°) in terms of Euler angles (?, ?, ?) disposed on the sapphire substrate, and electrodes disposed on the piezoelectric substrate and made of metal.

Abstract: An elliptical vibration is generated by combining a longitudinal primary resonance vibration of the vibrator resulting from an expansion and a contraction of the vibrator in a direction of the central axis and a torsional resonance vibration resulting from twisting of the vibrator around the central axis as a torsional axis. The dimension ratio of the rectangle of the vibrator is chosen such that a resonance frequency of the longitudinal primary resonance vibration resulting from the expansion and the contraction of the vibrator in the direction of the central axis and a resonance frequency of the torsional resonance vibrations resulting from twisting of the vibrator around the central axis as the torsional axis match. The ultrasonic motor further includes a vibration detecting electrode layer.

Abstract: A high power ultrasonic transducer includes a first ultrasonic transducer cell and at least one second ultrasonic transducer cell disposed on the first ultrasonic transducer cell. The at least one second ultrasonic transducer cell oscillates together with the first ultrasonic transducer cell.

Abstract: In an ultrasonic motor, an elliptical vibration is generated by combining a longitudinal primary resonance vibration resulting from an expansion and a contraction of the vibrator in a direction of the central axis and a torsional secondary resonance vibration or a torsional tertiary resonance vibration resulting from twisting of a rotation axis, and the dimension ratio of the rectangle of the vibrator is chosen such that a resonance frequency of the longitudinal primary resonance vibration, resulting from the expansion and the contraction of the vibrator in the direction of the central axis and a resonance frequency of the torsional secondary resonance vibration or the torsional tertiary resonance vibration resulting from twisting of the rotation axis match. The vibrator includes a torsional piezoelectric body that generates a thickness shear vibration, and that is arranged at an anti-node position of the torsional secondary resonance vibration or the torsional tertiary resonance vibration.

Abstract: In an ultrasonic motor, an elliptical vibration is generated by combining a longitudinal primary resonance vibration resulting from an expansion and a contraction of a vibrator in a direction of a central axis and a torsional secondary resonance vibration or a torsional tertiary resonance vibration resulting from twisting of a rotation axis. A dimension ratio of a rectangle of the vibrator is chosen such that a resonance frequency of the longitudinal primary resonance vibration and a resonance frequency of the torsional secondary resonance vibration or the torsional tertiary resonance vibration match. The vibrator includes a plurality of regions in a surface orthogonal to the central axis, and deformations of the regions adjacent to each other along the direction of the central axis are mutually different. The vibrator expands and contracts in a direction along a polarization direction thereof.