Abstract: The present invention relates to a microactuator that can be produced by utilizing the IC fabrication processes such as etching, lithography or the like and that can be used as a micropositioner in a multi probe head for scanning probe microscopy and a pickup head for recording and reproducing equipment. The microactuator comprises a plurality of electrodes arranged around the circumference of a circle, a ring-like displacement plate located inside said electrodes, beams which support said displacement plate elastically at one ends and at the same time are fixed at the other ends to a point located towards the inside of said displacement plate on a substrate and a voltage supply means to apply voltages to said electrodes in order for said electrodes to attract said displacement plate electrostatically. An extremely small, long life and high reliability microactuator that is excellent in mass-producibility and capable of high precision positioning can be realized.

Abstract: A method for controlling a capacitive actuator includes the steps of determining an energy applied to an actuator, measuring an actuator voltage present at the actuator, and inferring a functional state of the actuator by using the energy and the actuator voltage. A capacitive actuator is fed energy and the actuator voltage present at the actuator is measured. The energy and the comparison of the actuator voltage with reference values are used to infer a functional state, for example, either faults or correct function of the actuator or injection valve. Furthermore, the actuator voltage is used to infer an actuator stroke. The method is based on actuator characteristics.

Abstract: An object of the present invention is to provide a quartz resonator unit and a quartz oscillator having a small size and a light weight and having the capability of oscillating in the overtone mode, and also to provide a quartz element for use in the quartz resonator unit and quartz oscillator. Thus, a further object is to determine the optimum width-to-thickness ratio of the quartz element at which the quartz element having a width less than 1.5 mm and a length less than 4.7 mm does not show coupling with spurious vibrations over the entire range of operation temperature. From the experiments and evaluation performed repeatedly, it has been concluded that an AT-cut rectangular quartz element having the width-to-thickness ratio w/t in a range selected from the group consisting of 8.48 0.05, 12.18+/−0.05, 13.22+/−0.07, 14.78+/−0.07, and 15.57 0.07 is suitable as a small-sized quartz element that can oscillate at a high frequency and has excellent temperature characteristics.

Abstract: A stator includes a longitudinal-vibration sensing electrode. The stator also includes a torsional-vibration sensing piezoelectric element and a torsional-vibration sensing electrode plate for sensing torsional vibrations. A voltage signal from the torsional-vibration sensing electrode plate or a voltage signal from the longitudinal-vibration sensing electrode is sensed. Then, a drive voltage signal for driving the stator is generated in a self-excited oscillation drive circuit in such a manner that an actual vibrational frequency of the stator substantially coincides with a resonance frequency. Thereafter, the generated drive voltage signal is applied between a drive electrode and each one of first and second electrode plates.

Abstract: A piezoelectric motor having a stator and a rotor. The stator and the rotor are in mechanical contact with one another along at least one cylindrical friction surface by means of curved, elastic and longitudinally elongated pusher plates, the pusher plates being held against the friction surface at a first end of the pusher plates, and arranged at an angle to the friction surface. A piezoelectric element is connected to either the rotor or the stator. The piezoelectric element has electrodes placed on opposing surfaces of the piezoelectric element, and is connectable to an alternating current source via the electrodes for providing longitudinal oscillations in the piezoelectric element. A first ring plate and a second ring plate are arranged on opposite sides of the piezoelectric element, so that at least a portion of surfaces of the piezoelectric element are pressed against surfaces of the first ring plate and the second ring plate, respectively, by a clamping device.

Abstract: A differential circuit is used to compare the current to the drive transducers to a matched reference circuit. With the capacitive current from the piezoelectric transducer canceled out in this manner, the resulting output current provides a direct measure of the vibration amplitude of the drop generator. By adding an appropriate inductor in parallel to the capacitive piezoelectric drive transducers, the loading of the drive electronics, or oscillator, is significantly reduced.

Abstract: An apparatus for controlling a piezoelectric vibratory parts feeder comprises a piezoelectric vibrating unit provided with a piezoelectric vibrating element that vibrates at a predetermined frequency, a bowl adapted to discharge parts accommodated therein by means of the piezoelectric vibrating unit, a driving circuit for driving the piezoelectric vibrating element, and a control unit for outputting a driving signal to the driving circuit to cause a predetermined driving. The control is performed by idling the driving of the piezoelectric vibrating element temporarily at every predetermined driving cycles thereof and controlling the vibration of the piezoelectric vibrating element based on a signal obtained therefrom by its piezoelectric effect during the idling period, for instance, based on a phase difference between a waveform of this signal and the driving signal of the driving circuit.

Abstract: A flextensional transducer assembly having a single flextensional cell with a transducer housed with a platten. The transducer expands and contracts in a transverse direction to cause inverse movement in the platten in the axial direction. The platten may include either an elbow at the intersection of walls or corrugated pattern along the top and bottom walls. The platten is manufactured from one piece using Electrical Discharge Machining. A load is applied to the platten to then slot in the transducer into the platten before releasing the load to mechanically capture the transducer.

Abstract: The invention described herein is a novel power circuit capable of electrically driving devices whose mechanical action is accomplished by induced strain transducers. The power circuit neither recycles nor dissipates the energy returned from the near lossless transducer, instead redirects power either to another transducer of the same type or to the transducer itself. The invention is based on a balanced capacitive loading method wherein the load itself acts as the energy storage element in the energy balance system. In the preferred mode, the circuit directs power to a symmetric couple where both loads in the couple consist of one or more transductive elements. The invention eliminates the need for a large power-supply bypass capacitor in driving reactive loads thereby reducing the peak power handled by the d.c. power section.

Abstract: A resonator with mechanical node reinforcement includes a substrate, an intermediate portion adjacent to the substrate, and a resonant portion adjacent to the intermediate portion. The intermediate portion may include multiple layers, such as an insulating layer and/or a conductive layer. The resonant portion of the resonator is adapted for an oscillation mode with a nodal point located within its periphery. Preferably, the resonant portion contacts the intermediate portion at points located at the periphery and at the nodal point. The resonant portion may include multiple layers and its primary layer may be a membrane or a plate. An alternative embodiment of the resonator excludes the intermediate layer allowing the resonant portion to contact the substrate instead of the intermediate layer.

Abstract: A thin film resonator and method includes a first electrode (110) and a second electrode (112) substantially parallel to the first electrode (110). An intermediate layer (120) is disposed between and coupled to the first and second electrode (110, 112). The intermediate layer (120) includes a first piezoelectric layer (122), a second piezoelectric layer (124), and a spacer layer (130) disposed between the first and second piezoelectric layers (122, 124). The spacer layer (130) has an acoustic impedance substantially the same as the first and second piezoelectric layers (122, 124) and is formed of a disparate material.

Abstract: A piezoelectric/electrostrictive device is disclosed comprising a driving portion to be driven by a displacement of a piezoelectric/electrostrictive element, a movable portion to be operated by a drive of the driving portion, a fixing portion for holding the driving portion and the movable portion, the movable portion being coupled with the fixing portion via the driving portion, and a hole formed by inner walls of the driving portion, an inner wall of the movable portion, and an inner wall of the fixing portion.

Abstract: A crystal electrode that reduces coupled mode noise. A crystal blank has a top surface and a bottom surface. A first electrode is located on the top surface. The first electrode has a contact portion and a polygonal portion. A second electrode is located on the bottom surface. The second electrode has a contact portion and a polygonal portion. The polygonal portions of the first and second electrodes are arranged such that they oppose each other.

Abstract: The piezoelectric oscillator is a Colpitts circuit including a piezoelectric vibrator and a load capacitance in the oscillating loop and a limiter circuit. The excitation signal from the piezoelectic vibrator is supplied to the limiter circuit, and the limiter circuit controls the inter-terminal impedance of the capacitor which is connected to the limiter based on variations in the excitation signal and thus clips the level of the excitation signal.

Abstract: A laminated piezoelectric transformer according to the present invention comprises (a) a laminated body formed by laminating a plurality of ceramic layers and a plurality of internal electrodes and (b) a plurality of external electrodes electrically connected with the internal electrodes and disposed on the surface of the laminated body. Further, the internal electrodes of the laminated piezoelectric transformer of the invention are characterized by having a plurality of primary internal electrodes positioned at the middle portion along the longitudinal direction of the laminated body and a plurality of secondary internal electrodes positioned at both end portions of the laminated body. By virtue of this configuration of the invention, the polarization volume on the secondary side can be enlarged and, therefore, the laminated piezoelectric transformer of the invention can step up voltages at high energy conversion efficiency.

Abstract: A bulk acoustic wave device has a number of resonator elements (14) which are laterally spaced such that a signal (26) applied between to one resonator element (141) at a resonant frequency of the device is coupled to the other resonator elements (142, 143, 144) by acoustic coupling between piezoelectric layers of the resonator elements (14). There are two outer resonator elements (141, 145) and at least one inner resonator element (142, 143, 144). The terminals of the inner resonator elements are electrically connected together. This connection provides an AC short which eliminates the effect of the parasitic capacitances of the inner resonator elements, and provides electromagnetic shielding between the input and output of the device, by reducing the parasitic capacitance between the input and output upper electrodes.

Abstract: An outer coating substrate for an electronic component is constructed to be calcined at a low temperature, and greatly decreases the cost thereof while greatly improving the dimensional precision of the substrate. The outer coating substrate for an electronic component includes a multi-layered substrate including a first material layer that is sintered in a liquid phase and a second material layer that is not sintered at the sintering temperature of the first material layer. The first and second material layers are laminated, and calcined at the calcining temperature of the first material layer.

Abstract: A piezoelectric transformer includes an output part having laminated sheets formed of a first piezoelectric material and one or more input parts, each having laminated sheets made of a second piezoelectric material. The piezoelectric strain constant of the second piezoelectric material is greater than that of the first piezoelectric material.

Abstract: A piezo-electric/electrostrictive film type chip (50) includes: a ceramic substrate (70) having a spacer plate (74) having a windows-disposed pattern (100) having a plurality of window portions (75) and a thin closure plate (72) for closing the window portions (75) which is unitarily connected with the spacer plate; and a piezo-electric/electrostrictive working portion (71) having a lower electrode (81), a piezo-electric/electrostrictive layer (82), and an upper electrode (83), each being formed in the form of a layer and laminated in this order at a closure portion of the window (75) on the outer surface of the closure plate (72) by a film formation method. A pin hole (52) for positioning is formed in or near the center of gravity of the windows-disposed pattern (100).

Abstract: A piezoelectric/electrostrictive actuator including a ceramic substrate, and at least one piezoelectric/electrostrictive actuator unit formed on at least a portion of at least one surface of the substrate, each piezoelectric/electrostrictive actuator unit having a first electrode film, a piezoelectric/electrostrictive film and a second electrode film which are laminated in the order of description, with the piezoelectric/electrostrictive actuator unit formed on the substrate by heat treatment.