Abstract: A hearing-aid device and a method for transmitting sound through bone conduction are disclosed. The hearing-aid device comprises a piezoelectric-type actuator, housing and connector. The piezoelectric actuator is preferably a circular flextensional-type actuator mounted along its peripheral edge in a specifically designed circular structure of the housing. During operation, the bone-conduction transducer is placed against the mastoid area behind the ear of the patient. When the device is energized with an alternating electrical voltage, it flexes back and forth like a circular membrane sustained along its periphery and thus, vibrates as a consequence of the inverse piezoelectric effect. Due to the specific and unique designs proposed, these vibrations are directly transferred through the human skin to the bone structure (the skull) and provide a means for the sound to be transmitted for patients with hearing malfunctions.

Abstract: A self-powered switching system using electromechanical generators generates power for activation of a latching relay. The electromechanical generators comprise electroactive elements or magnetic based microgenerators that may be mechanically actuated to generate electrical power. The associated signal generation circuitry may be coupled to a transmitter or transceiver for sending and/or receiving RF signals to/from a receiver which actuates the latching relay. Power may be stored within the circuit using rechargeable batteries for powering or supplementing power to the transmitter or transceiver.

Abstract: A self-powered switching system using electromechanical generators generates power for activation of a latching relay, switch, solenoid or latch pin. The electromechanical generators comprise electroactive elements that may be mechanically actuated to generate electrical power. The associated signal generation circuitry may be coupled to a transmitter for sending RF signals to a receiver which actuates the latching relay. The use of mechanically activated membrane switches on the deflector or on a keypad allows multiple code sequences to be generated for activating electrical appliances or an electromechanical locking system.

Abstract: A self-powered switching system using electromechanical generators generates power for activation of a latching relay. The electromechanical generators comprise electroactive elements or magnetic based microgenerators that may be mechanically actuated to generate electrical power. The associated signal generation circuitry may be coupled to a transmitter or transceiver for sending and/or receiving RF signals to/from a receiver which actuates the latching relay. Power may be stored within the circuit using rechargeable batteries for powering or supplementing power to the transmitter or transceiver.

Abstract: A self-powered switching device using a prestressed flextensional electroactive member generates a signal for activation of a latching relay. The electroactive member has a piezoelectric element with a convex and a concave face that may be compressed to generate an electrical pulse. The flextensional electroactive member and associated signal generation circuitry can be hardwired directly to the latching relay or may be coupled to a transmitter for sending an RF signal to a receiver which actuates the latching relay.

Abstract: A laminated piezoelectric transformer is provided using the longitudinal vibration modes for step-up voltage conversion applications. The input portions are polarized to deform in a longitudinal plane and are bonded to an output portion. The deformation of the input portions is mechanically coupled to the output portion, which deforms in the same longitudinal direction relative to the input portion. The output portion is polarized in the thickness direction relative its electrodes, and piezoelectrically generates a stepped-up output voltage.

Abstract: A modular design for combining piezoelectric transformers is provided for high voltage and high power conversion applications. The input portions of individual piezoelectric transformers are driven for a single power supply. This created the vibration and the conversion of electrical to electrical energy from the input to the output of the transformers. The output portions of the single piezoelectric transformers are combining in series and/or parallel to provide multiple outputs having different rating of voltage and current.

Abstract: A thickness mode piezoelectric transducer is provided that has masses attached to opposing faces of the transformer. The end-masses increase the thickness of the transformer and decrease its resonant frequency. The end-masses increase the magnitude of resonant vibrations in the output layer(s) as well as the mechanical Q of the device to provide a low profile piezoelectric transformer with high power density. Each of the input and output portions is resonant tank circuit having a electrical resonant frequency substantially matching the mechanical resonance whereby the amplitude of the mechanical vibrations are increased. These mechanical vibrations are used in conjunction with a mechanical amplifier or horn for use of the device as a vibrational transducer.

Abstract: A self-powered switching device using a prestressed flextensional electroactive member generates a signal for activation of a latching relay. The electroactive member has a piezoelectric element with a convex and a concave face that may be compressed to generate an electrical pulse. The flextensional electroactive member and associated signal generation circuitry can be hardwired directly to the latching relay or may be coupled to a transmitter for sending an RF signal to a receiver which actuates the latching relay.

Abstract: A method of finishing concrete using a vibrating tool to consolidate a “dry shake” aggregate into the upper layer of the concrete. The use of the vibrating tool causes moisture within the concrete mass to migrate into the surface layer where the moisture may hydrate the aggregates in the dry shake mixture. The ability to cause upward migration of water in the concrete mass provides a larger window of finishability for the concrete. The vibrations also provide thorough consolidation of aggregates in the upper layer of the concrete mass helping to prevent delamination.

Abstract: A self-powered switching device using a prestressed flextensional electroactive member generates a signal for activation of a latching relay. The electroactive member has a piezoelectric element with a convex and a concave face that may be compressed to generate an electrical pulse. The flextensional electroactive member and associated signal generation circuitry can be hardwired directly to the latching relay or may be coupled to a transmitter for sending an RF signal to a receiver which actuates the latching relay.

Abstract: The present invention relates to a multilayer piezoelectric transformer that uses a composite resonant vibration mode for step-up voltage conversion. More specifically, a multilayer piezoelectric transformer is provided using radial and shear vibration modes for step-up voltage conversion applications. Adjacent layers of piezoelectric ceramic act as a constraint on the deformation of one face of the input layers, leading to a gradient in the radial deformation of both the input and output portions. The piezoelectric transformer is used in a circuit for providing electro-luminescent (EL) backlighting.

Abstract: A piezoelectrically actuated vibratory motor comprises actuators that are mounted “vertically” with their edges attached to top and bottom mounting members. An oscillating voltage applied to the actuators causes them to contract and expand to move the attached mounting members in a direction essentially parallel to the faces of the actuators. The force transmitted to the mounting members at the edges of actuators is greater than the typical force taken at the center of a face of the actuator.

Abstract: A piezoelectric transformer is provided having segmented electrodes on one or both faces of a piezoelectric ceramic disk. Application of a voltage sequentially to one or more adjacent segments forms a travelling wave in the disk. Application of a voltage to alternate segments forms a resonant standing wave in the disk. The transformer may be configured with a resonant feedback circuit that provides step up voltage transformation, and may provide voltage to multiple loads.

Abstract: A multi-layer piezoelectric transformer (PT) is provided having an insulation layer having an input electroactive ceramic layer bonded to one of its major faces and an output electroactive ceramic layer bonded to its other major face. The input layer is electroded on both major faces and is poled in the thickness direction. The output layer has segmented electrodes patterned on its two opposing major faces and portions of the output layer are alternatingly poled in opposite directions across the output layer's thickness. The configuration of the poling and electrodes places adjacent portions of the output layer electrically in series.

Abstract: An inverter circuit is provided using a voltage converter having multiple layers of piezoelectric ceramic. More specifically, the present invention provides an inverter circuit for a Cold Cathode Fluorescent Lamp (CCFL) incorporating a multilayer piezoelectric transformer that uses the longitudinal resonant vibration mode for step-up voltage conversion. The transformer is driven by a FET half-bridge connected to an oscillator through dual current buffers, one current buffer being driven through and a level shifter and charge pump.

Abstract: A method and apparatus for manufacturing prestressed piezoelectric actuators which maximizes output, and increases the precision and efficiency with which the multi-layer actuators are made. Individual layers of the piezoelectric actuators are automatically stacked and registered with respect to each other within press members prior to bonding the layers to each other with a thermoplastic adhesive. Compressive force is applied while heat is conductively transferred from a heating element to the actuator in order to raise the temperature of each of the layers above the melting point of the thermoplastic. The temperature of the heating element is then decreased until the temperature of the actuator layers drops to below the melting point of the thermoplastic adhesive, thereby bonding the layers. Compressive force is then released, and the actuators are removed, further cooled and polarized.

Abstract: A circuit including a transformer, preferably a laminated piezoelectric transducer, in combination with a positive feedback amplifier circuit, capable of serving: 1) to produce either an audible or ultrasonic signal; or 2) as an energy source capable of driving an auxiliary high voltage device with an initial and continuing low voltage source such as a battery.

Abstract: A method for manufacturing high deformation piezoelectric actuators and sensors using a continuous tape manufacturing process is provided. The ceramic layer is dispensed between two metal/adhesive layers to form a composite tape and is tack welded together. Lengths of composite tape are heated and then cut into individual actuators. A special pattern punched in the tapes allows for ease of alignment of the layers of the actuators.

Abstract: A multi-layered piezoelectric electrical energy transfer device has its input and output sides electrically isolated from each other. As a transformer, the device provides step-down voltage conversion while the output signal preserves the input signal frequency in a broad bandwidth. For telecommunications applications, the transformer can provide impedance matching with transmission lines, which minimizes line losses and echoes that seriously degrade high-speed data transmission. The piezoelectric transformer also provides a uniform voltage transformation ratio (Vout/Vin) over wide frequency ranges, and is adaptable for simultaneous audio and data signal telecommunications applications requiring wide bandwidth service.