Abstract: In a vibration wave motor, a plurality of electrostrictive elements are phase-differentially arranged or polarized on a ring-shaped vibration member having a thickness which increases as it radially goes from a center to an outer circumference, periodic voltages are applied to the electrostrictive elements to generate a travelling vibration wave in the vibration member, and a movable member press-contacted to the vibration member is friction-driven by the travelling vibration wave.

Abstract: An ultrasonic wave conversion apparatus comprises electrodes, a support member for supporting the electrodes, a vibrator secured to the support member by a securing member, and a moving diaphragm fixed to the vibrator by a fixing member. The surface of portions of the electrodes, the vibrator, the moving diaphragm and the fixing member are coated with an insulating film of a predetermined thickness. The coating with this insulating film provides the apparatus with an excellent insulating and anticorrosive property and further an excellent damping characteristic for the vibration of the vibrating members of the apparatus.

Abstract: A force and pressure transducer comprises a plate-like crystal. Two separate portions of the crystal are maintained in oscillation at separate frequencies by a circuit. The force to be measured, is applied by a seating to a part of the crystal edge such that compression in one of the oscillating portions causes the frequency of that oscillating portion to change substantially whereas the frequency of the other portion changes only minimally.In the past it has been difficult to manufacture crystals in which the frequency versus temperature response of each of the two oscillating portions was sufficiently well matched to permit the difference frequency between the portions to be used as the instrument output signal.This invention resides in the application of a second fixed force by a spring via a seating to a second part of the crystal edge in such a way as to influence the frequency of oscillation of this second portion.

Abstract: A piezoelectric tuning fork vibrator used as an oscillator or a detection element in various electronic circuits, which is provided at a vibrator body with a slit to form tuning fork legs at both sides, one leg at the vibrator having at the outside surface a piezoelectric thin film and an electrode thereon, so that the one leg including the piezoelectric thin film and electrode, is made equal in width to the other leg.Hence, the both side tuning fork legs equal in width become equal in the resonance frequency and avoids leakage of vibration energy, whereby this piezoelectric vibrator is free from characteristic variation and has a high accuracy.

Abstract: A piezoelectric vibrating device comprises a vibrating element supported by a support frame through at least two arms with the support frame surrounding the vibrating element. The vibrating element, the support frame and the support arms are of one-piece construction fabricated from a sheet of temperature-stable metal of constant elasticity. A ZnO layer is formed so as to overlay the vibrating element and also a portion of the support frame, and electrodes are formed so as to overlay a part of the ZnO layer on the vibrating element and another part of the ZnO layer on the support frame, respectively. One of the electrodes on the other part of the ZnO layer cooperates with the metal of constant elasticity to define a static capacitance with the ZnO layer serving as a dielectric body. An aluminum layer is interposed between the ZnO layer and the vibrating element.

Abstract: A piezoelectric generator for converting acoustic energy in a predetermined frequency range to electric energy including: a piezoelectric bending element; means for mounting the piezoelectric bending element in an acoustic energy path; tuning means mounted to the piezoelectric bending element to set the resonant frequency of oscillation of the piezoelectric bending element within the predetermined frequency range.

Abstract: An ultrasonic transmitting and receiving device comprises a bimorph vibrator including two piezoelectric elements each connected electrically to the corresponding one of a plurality of terminals for receiving and delivering electric signals and a metallic member made of a thin metal plate and including a flat plate portion and a cylindrical portion extending from the circumferential periphery of the flat plate portion. The flat plate portion is placed between the piezoelectric elements and the cylindrical portion increases in outer diameter as it becomes distant from the flat plate portion.

Abstract: A single beam force transducer is provided with integrally affixed isolation springs which are axially compliant and unbalanced in their spring rates so as to induce beam bending due to applied tension and compression. The amount of bending introduced due to applied tension will be of a precise magnitude so as to substantially cancel undesirable non-linear vibration effects.

Abstract: An Al electrode structure for a zinc oxide thin film in which an intermediate layer of V.sub.2 O.sub.3, Ta, V, Cu, Ni or Ti is provided between the surface of the zinc oxide thin film and the Al electrode. A tuning fork vibrator equipped with such an electrode structure has high reliability in that changes in resonance frequency and series resonance resistance (Ro) with time are small.

Abstract: A single beam force transducer has a beam characterized by a thickened central portion and tapered outward portions. The support members of the transducer are thickened and are thus stiffer while the isolator masses are shortened. These critical configuration changes raise the undesirable "tuning fork" resonant frequency of the beam supporting structure far above that of the beam and ensures that the isolating structure behaves as a rigid body.

Abstract: A variable pressure piezo electric generator comprised of a furnace chamber, a refrigerant chamber surrounding the furnace chamber in heat exchange relation thereto and a condensing chamber in communication with the refrigerant chamber. The refrigerant chamber contains a liquid refrigerant that is vaporized by the furnace heat and flows into and through the condensing chamber where it condenses. Piezo electric elements are mounted in the condensing chamber in the path of the pressurized refrigerant. An apertured plate is mounted in the condensing chamber between adjacent pairs of the piezo electric elements. The apertures in the respective plates vary in size which causes refrigerant pressure variations. As a result, the refrigerant exerts mechanical forces on the piezo electric elements causing them to produce electricity.

Abstract: A piezoelectric loudspeaker thin plate-like shaped and using a piezoelectric ceramic plate for a sound-generating portion, which comprises a disc-shaped diaphragm formed of a metallic plate, a disc-shaped film using a material of a smaller Q-factor and formed about equal in diameter to the disc-shaped diaphragm, and a disc-shaped piezoelectric ceramic plate smaller in diameter than the disc-shaped diaphragm, these three members being stuck concentrically with each other, so that the integral-stuck member is supported at its outer peripheral portion to a frame.

Abstract: An electrode structure for a zinc oxide thin film having a SnO.sub.2 layer between the surface of the zinc oxide thin film and the electrode. A tuning fork vibrator equipped with such a structure has a high reliability in that changes in resonance frequency and insulation resistance (IR) with time are small and the increase in series resonance resistance (R.sub.O) is small.

Abstract: The resonance of a piezoelectric vibrating element itself sets the frequency of the excitation producing ac oscillator for e.g. Kelvin probe or chopper applications.The oscillation amplitude is continuously adjustable. The superposition of a dc voltage in addition to the ac excitation voltage renders a continuously adjustment of the mean spacing of the working electrodes. A phase stable reference signal is provided for phase sensitive amplifier synchronization.

Abstract: A mounting structure for crystal resonators used as frequency standards and transducers which maximizes performance and reduces the sensitivity to environmental errors. In one embodiment, force sensitive crystal resonators having inherent unmounted temperature sensitivities are used in conjunction with reactive spring-like mounting arrangements having predetermined temperature stress characteristics such that the thermally induced mechanical stress of the mounting arrangements changes, compensates, and optimizes the overall combined temperature characteristics. In another embodiment crystal resonators are isolated from the external environment so that they are capable of sensing forces while operating in a vacuum or inert atmosphere. Environmental isolation is provided by bellows and/or diaphragm arrangements used alone or in conjunction with air-tight enclosures which enable forces to be applied to stress-sensitive crystals while isolating the crystals from the external force producing environment.

Abstract: A piezoelectric cone-type speaker having a multiple structure in which a plurality of piezoelectric elements and speaker diaphragms individually coupled to them are coaxially or multi-axially arranged. It has a wide frequency range. A cushioning member is interposed between one diaphragm and another so that each element is isolated from the vibrations of another element.

Abstract: A rotative motor includes a member mounted to rotate freely. A plurality of piezoelectric bimorph elements are radially secured at one end to a support in a two-staged shape comprising upper and lower arrays of the elements. A plurality of elastic members connect the free end of each one of the upper elements with the free end of a different one of the lower elements. Each pair of inter-connected elements is excited from a source of alternating current so that the free ends of the respective elements vibrate ninety degrees out of phase. The central point of each elastic member connected between the free ends of the one upper and one lower elements is in frictional contact with the rotatable member. The central point of each elastic member exhibits a closed loop path, imparting a rotary motion to the rotatable member.

Abstract: Electro-acoustic transducer element having its resonant frequency in a lower frequency range advantageously usable for diagnostic purposes comprises a polymeric piezoelectric film such as polyvinylidene fluoride film being coupled with an additional layer having a thickness specified in relation to the wavelength of sound waves within the additional layer at the free resonant frequency of the polymeric piezoelectric film, the additional layer having an acoustic impedance related to the acoustic impedance of the polymeric piezoelectric film.

Abstract: A broadly tuned self resonant knock sensor includes a piezoelectric element mounted on a central mounting stud. The element includes a generally annular vibratable portion having a variable radial dimension so as to exhibit resonant vibrations at a plurality of relatively closely spaced resonant frequencies essentially spanning an engine determined knock frequency band. In its preferred embodiment the element comprises a circular plate having piezoelectric generating means and an axis offset from the axis of the mounting stud.

Abstract: This invention intends to provide a speaker which assumes a comparatively large area in a device without spoiling various display effects. The transparent flat panel speaker of this invention is a speaker of high efficiency which can give forth a sound volume large considering the small-sized device even when driven by a low voltage.The transparent flat panel speaker of this invention comprises, at least, a transparent resonator plate and a plate of a piezoelectric material held between at least one pair of electrodes, the resonator being excited by the piezoelectric material plate, a periphery of the resonator plate having a shape which is represented by a curve or in which straight lines are connected by smooth curves with at least two centers of curvature.As the peripheral shapes, an ellipse, a curve expressed by X.sup.n /a+Y.sup.n /b=1, a plane figure obtained by molding the corners of a polygon circumscribed or inscribed to an ellipse, etc. are especially favorable for the speaker.

Abstract: The present invention is directed to a tuning fork wherein a damping piece is provided, either integral with said tuning fork vibrator or a separate piece attached thereto, and wherein a damper member is intersected between said damping piece and a housing for accommodating the tuning fork vibrator.Since the (1/2)f.sub.O spurious response which is caused in the tuning fork vibrator to be spread within the damping piece is adapted to be absorbed by the damper member, the tuning fork is made smaller in shape.

Abstract: A rotative motor includes a member mounted to rotate freely. A pair of piezoelectric bimorph elements are excited from a source of alternating current so that free ends of the respective elements vibrate ninety degrees out of phase. The central point of an elastic member connected between the free ends of the elements is in frictional contact with the rotatable member. The central point exhibits a physical displacement circular in shape, imparting a rotary motion to the rotatable member.

Abstract: A tuned acoustic directional transducer for transmitting and receiving airborne sound, which provides enhanced efficiency and reduced cost without undue narrowing of bandwidth, makes use of an acoustic transducer element (2) coupled to a plate (10) having a higher order flexural mode resonance at approximately the desired frequency of operation, the plate being coupled to the air through low-hysteresis acoustic propagation material having an acoustic impedance much less than that of the plate and much greater than that of the air. The material is disposed so that in the desired direction of propagation there is no substantial reduction of sound intensity in the far field resulting from cancellation occasioned by interaction of sound radiated from adjacent antinodal zones. Preferably the thickness of the material is such that it acts as an efficient acoustic impedance matching transformer.

Abstract: In a piezoelectric tuning fork of the type which is used as an electro-mechanical filter and wherein a tuning fork is directly supported by a supporting member extended from a terminal plate, the supporting member is surrounded with a vibration isolation or absorbing member which in turn is bonded or otherwise joined to both the supporting member and the terminal plate, whereby the noise output due to the transmission of external vibrations or impacts may be considerably suppressed.

Abstract: A system for isolating the mounting pads of a vibrating beam or tuning fork force transducers from longitudinal vibrations generated by transverse vibrations of the beam or tuning fork tines which extend between the mounting pads. The system includes an arrangement of longitudinally resilient support links and masses that flex responsive to change in the length of the beam or tines as the beam or tines vibrate transversely. The support links and masses thus isolate the mounting pads from the longitudinally vibrations of the beam or tuning fork tines while allowing transmission of forces applied between the mounting pads which vary the force dependent resonant frequency of the beam or tuning fork.

Abstract: An electroexpansive linear actuator utilizes a sagittal tension member to amplify linear motion in which the electroexpansive member is placed in compression between a fixed base support and a lever support member hingedly connected to the fixed base. One end of the sagittal tension member is attached to the fixed base while the other end is attached to the lever support member distal the hinge point. The device to be actuated is connected proximate the midpoint of the sagittal tension member and moves perpendicular to the longitudinal axis of the sagittal tension member when the electroexpansive member expands and contracts. A second embodiment of the actuator utilizes a second lever support arm instead of the fixed base as a bearing support for the other end of the electroexpansive member.

Abstract: An apparatus for detecting a residual quantity of toner remaining in the supply hopper of a copying machine includes a piezoelectric vibrating element disposed in a wall of the hopper and having a surface normally positioned in contact with toner in the hopper, and an electronic circuit for causing vibration of the element at a predetermined frequency and for detecting changes in operating characteristics of the element as representative of a decrease in the amount of toner in the hopper to operate a warning device.

Abstract: A piezoelectric transducer drive for use within a ring laser gyro is shown wherein a resistive element is combined in a negative feedback loop with a second resistive element to provide a feedback signal which is constant with variations in the transducer material and linear with temperature change. The feedback signal is amplified and applied to a comparator whose output is modulated with an AC signal and applied to a power amplifier that drives the piezoelectric transducer for controlling the displacement thereof uniformly over a wide temperature range.

Abstract: A tuning fork resonator device includes a substrate having a recess formed in its one flat surface for receiving a damper made of an electrically conductive rubber and a metal leaf spring mounted on the substrate and being held in contact with the damper. A tuning fork is mounted on the damper through a support which is made of an electrical conductive material so as to electrically connect the tuning fork with the leaf spring.

Abstract: Device for vibrationally deviating an optical beam. It includes a frame, a main mechanical resonator, an auxiliary mechanical resonator and vibration generator means. The main mechanical resonator is formed of an optical member such as a mirror and resilient means connected to the optical member and the vibration generator means impress upon the optical member through the resilient means a rotational or translational motion, the frequency of which is that of the main resonator. The auxiliary resonator is formed of resilient blades having a free end and another end connected to the frame and its resonance frequency of the auxiliary resonator is equal to the resonance frequency of the main resonator. The two resonators vibrate in phase opposition in order that the periodic mechanical stresses applied respectively by the two resonators to the frame have at any instant, one and the same direction and opposite senses.

Abstract: A piezoelectric tuning fork device comprises a plate-like tuning vibrator having a pair of prongs and a base with a slot defined between the prongs. The tuning vibrator has at least one electrode layer deposited on and overlying a piezoelectric layer formed on one of the opposed major surfaces of the tuning vibrator. The electrode layer is generally U-shaped and has a pair of opposed leg portions each so positioned as to have its longitudinal axis located to one side of the imaginary corresponding prong.

Abstract: The present invention is an inertial rate of turn sensor of the vibratory type employing force feed back techniques for maintaining the free end of a cantilever in a nulled lineal path, constant with respect to the casing of the instrument. The current required to maintain the constant lineal path is then a measure of the amplitude of the rate of turn of the case and the phase sense of that current defines the sense of rotation of the case and therefor of the craft.

Abstract: A piezoelectric knock sensor comprises a flexing plate at one end of a generally cylindrical case with a mounting stud extending perpendicularly therefrom and a piezoelectric element attached to the flexing plate within the case for flexure with the flexing plate. When the sensor is attached to a component of a multicylinder, internal combustion engine, the case vibrates interactively with at least a portion of the component through the flexing plate and exhibits both an interactive resonance with the component for a wide resonance peak and response to transverse as well as axial vibrations. The sensor is thus capable of resonant response to knock-induced vibrations from all the cylinders even if the characteristic knock frequencies of the individual cylinders differ over a range too great to be encompassed by a self-resonant sensor. In addition, the sensor has the comparatively high output level of a piezoelectric device and simple construction suitable for mass production.

Abstract: A compact portable housing encloses a piezoelectric element which receives short pulses from a pulse generator circuit controlled by a ramping waveform generator circuit so that the element and the adjacent speaker portion of the housing produce a frequency modulated loud sweeping sound. The housing also encloses a detector switch for sensing a disturbance, and the sensitivity of the switch may be adjusted according to the position of the housing. The detector switch actuates a timer circuit which is armed or disarmed by moving a combination code switch having code wheels projecting from the housing.

Abstract: A knocking detector for an internal combustion engine includes a vibration unit comprising an inertial mass member and springs which are mounted in a housing attached to an engine body. The spring constants of the springs are so selected that the resonant frequency of the vibration unit becomes substantilly equal to the frequency of vibration due to knocking of the engine, and the vibration of the vibration unit is detected and converted into an electric signal.

Abstract: A tuning fork wherein a tuning fork vibrator is supported on a damping member mounted in a housing and having such characteristics that it will cancel the (1/2)f.sub.0 of spurious response of the tuning fork vibrator without impeding the normal vibration of the tuning fork vibrator, whereby the size of the tuning fork can be minimized.

Abstract: The resonant frequency of piezoelectric transducers is made more uniform from unit to unit by reducing the sensitivity of that frequency to manufacturing variations in the diameter of the ceramic sensing disk that forms a part of the vibratory diaphragm assembly. The diaphragm member proper is stiffened, as by integrally formed radial ribs, within the zone of variability of the disk perimeter, effectively establishing a uniform boundary edge for the diaphragm area that is stiffened by presence of the disk.

Abstract: A sensor device having a vibratable surface which can be exposed to variousmaterials and used to determine the presence thereof is disclosed. The device includes a sandwich structure comprising a substrate coated with a piezoelectric material, a pickup electrode joined to the piezoelectric and a drive electrode also joined to the piezoelectric. The piezoelectric material is applied to the substrate as a slurry and when dried forms a ceramic coating which is chemically bonded to the substrate. The sensor is electrically driven to vibrate and depending upon the absence or presence of the material to be detected a characteristic vibrational frequency or amplitude of the sensing surface is observed to indicate contact with such material. Various embodiments are discussed including a rectangular configuration which is cantilevered from a support base and a circular configuration which is held circumferentially by the support base.

Abstract: A tuning fork and a manufacturing method thereof which is obtained by punching and folding a material of invariable elasticity. The material is formed in the shape of a plate and processed through a rolling operation, wherein the plate is punched into an approximately V-shape such that the folding line appears at a right angle with respect to the rolling direction of the plate. A piezoelectric element serving as an electrical mechanical conversion device is provided on a vibrating portion.

Abstract: A tuning fork resonator which has a substantially U-shaped tuning fork supported in spaced relation to a support base by means of a support system with at least three support points. The three-point support system includes a pair of support rods holding the tuning fork therebetween and at least one electrode terminal pin supporting the tuning fork at one end face thereof. A piezoelectric transducer element provided for at least one of the opposed tines of the tuning fork is electrically connected to the terminal pin by means of an electroconductive elastic deposit of a bonding agent. An electrically insulating and shock and vibration absorbing layer is provided between the bottom of the tuning fork and the end face of the terminal pin which is held in contact therewith.

Abstract: Arrangements are disclosed for substantially reducing the effect of the inherent transducer capacitance in a transducer-coupled electromechanical system which is subject to vibrational movement. Electrical circuitry is coupled across the transducer output to provide a negative capacitance having a magnitude substantially the same as that of the inherent transducer capacitance, thereby substantially nullifying the inherent transducer capacitance and enabling improved damping (including low-noise damping) to be achieved.

Abstract: A composite low frequency transducer that makes it possible to lower the ural frequency and use higher power levels than can be obtained with a ceramic transducer alone. The transducer includes metal and ceramic elements. The metal element consists of a cylindrical shell which is multiply slitted longitudinally and alternately from each end, the alternate slits extending substantially but not completely to the opposite end. The ceramic transducer element is cylindrical and is in contact with and centrally positioned within the slitted exterior shell. The resulting composite transducer operates at a frequency which is several octaves less than the natural lowest frequency of the ceramic transducer alone.

Abstract: An electromechanical filter comprising a plurality of parallel mounted mechanical resonators which are generally cylindrical in shape with a plurality of input and output resonators operating in a bending mode and at least one intermediate mechanical resonator operating in a torsional mode and being generally dumbbell shaped with two or more cylindrical portions connected by a torsion member and with electrostrictive transducer input and output members connected to the input and output resonators so as to provide filters having wide band characteristics.

Abstract: A sand transport detector which detects the discrete impingements of sand particles on an elongated probe member inserted into the sand. A piezoelectric transducer element is cemented to the probe and produces an output signal when impingement occurs. With an electronic circuit coupled to the transducer, an indication of sand transport may be obtained.

Abstract: In an electromechanical filter comprising longitudinally vibrating resonators intercoupled by means of longitudinally vibrating rods, the transducers each consist of two halves located on two flats machined on the same outermost resonator along two parallel planes.

Abstract: A spring member is resin bonded to a piezoelectric material body at one end nd at the other end carries the oscillating electrode of a Kelvin probe capacitor used for electron work function measurement under vacuum. The piezoelectric material body can be either a piezoelectric crystal or a piezoceramic. An alternating voltage causes it to vibrate the spring member at a resonant frequency, so that a still greater amplitude of vibration is produced at the electrode. A superimposed d-c voltage is applied to the piezoelectric material body to set the average spacing between the movable reference electrode and the fixed sample electrode. A polyurethane-based resin provides vacuum-proof bonding. The piezoelectric material body and spring are mounted in a tube providing electrostatic shielding.

Abstract: A piece of flexible tubing is positioned within the cover of a crystal mount and surrounds a planar crystal without engaging the crystal or obstructing its vibration due to electrical signals applied to the crystal. The shape of the tubing is such that it resiliently engages the cover walls at a plurality of locations and provides free portions therebetween that function as cushions for limiting the movement of the crystal in response to accelerating or decelerating shock forces applied to the crystal in a direction transverse to the plane of the crystal.

Abstract: The monitor is used with seeder equipment having one or more seeder hopper sections wherein each hopper section has a number of metering assemblies for feeding the seed from each hopper section to the soil. The monitoring apparatus includes at least one sensor consisting of a piezoelectric transducer which provides an output signal in response to being struck by a seed, a vibration isolating mounting structure to position the sensor in the seed flow path between the metering assembly and the soil, and a circuit for receiving the sensor electronic response and providing an indication of seed flow condition. The mounting structure includes an elongated member such as a metal tubing, to one end of which is fixed a cushion made of a material such as a closed cell foam and to the other end of which is fixed a securing member to secure the structure to the seeder.

Abstract: A trapped energy type of piezoelectric filter includes a polarized ceramic wafer 9, input and output electrodes 11, 13 secured to one major surface of the wafer and spaced from each other by a constant width gap, and a ground electrode 15 secured to the opposite major surface underlying the input and output electrodes. The configuration of the ground electrode is made symmetrically concave or convex about its longitudinal axis in varying degrees to thereby control the band pass width, the symmetry of the filter characteristic about a center frequency, and eliminate peak ripples.

Abstract: A band-pass electromechanical filter, comprising an input electromechanical transducer, an output electromechanical transducer and a mechanical filter disposed therebetween, said filter having, alternately disposed, p resonators and (p - 1) coupling pins, resonating all in the longitudinal mode, wherein the coupling pins have identical diameters and lengths varied according to their respective position within said mechanical filter, said length being maximum in the middle of the filter and progressively decreasing towards the ends thereof.