Abstract: A wireless switch is provided having a twenty-year life energy harvesting arrangement for self-powering a wireless transmitter. The energy harvesting arrangement is implemented in one embodiment using a piezoelectric switch element. A tritium light source and photovoltaic device are used in a second embodiment, while a black light source and photovoltaic device are used in a third embodiment. The energy harvesting wireless switch arrangement of the present invention can be combined, for example, with a vehicle side mirror switch, to reduce the complexity of the wire harness feeding the door. The wireless switch can be located without regard to accessability of a wiring harness or connector.

Abstract: Chips, and methods of manufacturing thereof, comprising a base having a surface, and a plurality of components integrated in the base. Each component is coupled to at least one individual electrode disposed on the surface and to a counter-electrode. Each component operates as an electric generator, when activated by a power supply external to the chip. The counter-electrode is disposed such that each activated component creates a polarization voltage and/or a polarization current between that at least one individual electrode and the counter-electrode, when a medium is brought into contact with the surface.

Abstract: A liquid injection apparatus includes an injection unit having piezoelectric/electrostrictive elements; a solenoid-operated on-off discharge valve for discharging fuel under pressure into the injection unit; and an electrical control unit. The electrical control unit sends a solenoid valve on-off signal to the solenoid-operated on-off discharge valve on the basis of operating conditions of an engine, whereby liquid fuel is fed under pressure to the injection unit from the solenoid-operated on-off discharge valve. When liquid pressure in the injection unit detected by a liquid feed path pressure sensor is judged to be in the process of increasing or lowering, the electrical control unit activates the piezoelectric/electrostrictive elements, thereby atomizing injected fuel. When the detected liquid pressure in the injection unit is judged to be a constant, low pressure, the electrical control unit inactivates the piezoelectric/electrostrictive elements, thereby reducing electrical consumption.

Abstract: A remote device such as a control value (4) is powered and controlled by optical energy, supplied by an intensity-modulated light source (8) and optical fibre (10). After conversion into electrical form, the light is detected at (12) and applied to a piezoelectric transformer (14). The output of the transformer powers and control an actuator (16) of the control value.

Abstract: The use of newly discovered chemical reaction products, created when reactants combine to form products on the surface of a catalyst, to generate electricity, beams of radiation or mechanical motion. The invention also provides methods to convert the products into electricity or motion. The electric generator consists of a catalyst nanocluster, nanolayer or quantum well placed on a substrate consisting of a semiconductor diode, and a semiconductor diode on the surface of the substrate near the catalyst. The device to generate mechanical motion consists of a catalyst nanocluster, nanolayer or quantum well placed on a substrate, and a hydraulic fluid in contact with the non-reaction side of the substrate, with the surfaces of both the catalyst and substrate mechanically formed to enhance the unidirectional forces on the fluid. Both devices use a fuel-oxidizer mixture brought in contact with the catalyst.

Abstract: An integrated MEMS resonant generator system includes a substrate, a plurality of piezoelectric micro generators disposed on the substrate, the micro generators each generating a voltage output in response to vibrational energy received, and at least one power processor disposed on the substrate. The power processor electrically coupled to outputs of the plurality of micro generators. When the input conditions change, the power processor can dynamically adjust its switching functions to optimize the power delivered to a load or energy storage reservoir.

Abstract: An actuator using a piezoelectric element. The actuator includes: the piezoelectric element, which is capacitive; an inductor; and a resistor. The piezoelectric element, the inductor and the resistor are serially arranged so as to define a serial circuit. When a suitable voltage is supplied to the serial circuit, a saw-tooth waveform voltage is applied to the piezoelectric element so that the piezoelectric element extends at a speed and compresses at a different speed repeatedly.

Abstract: A transmit pulser includes an H-bridge of four transistors. First and second transistors of the H-bridge connect with a first electrode of a transducer element, and third and fourth transistors of the H-bridge connect with a second electrode of the transducer element. A differential receive amplifier connects with the first and third transistors. First and second diode clamps connect with the first and third transistors, respectively, and the inputs to the differential receive amplifier. The second and fourth transistors connect to a same power or voltage source, imposing a same voltage in either a forward or a reverse direction. By using matched transistor pairs (e.g. first and third matched pair and second and fourth matched pair), symmetrical transmit waveforms are generated. Symmetrical transmit waveforms allow for using phase inversion or phase differences between transmit waveforms for imaging, such as for harmonic imaging of tissue.

Abstract: An apparatus and method for extracting energy is provided. In one aspect the method includes using chemical reactions to generate vibrationally excited molecules, such as high-quantum-number-vibrationally-excited gas molecules in a region. The vibration energy in the vibrationally excited molecules is converted into hot electrons when the excited molecules contact a conductor. A geometry is provided so that the excited molecules may travel, diffuse or wander into a conductor before loosing a useful fraction of the vibrational energy. Optionally, the generating and the converting process may be thermally separated, at least in part. The short lived hot electrons are converted into longer lived entities such as carriers and potentials in a semiconductor, where the energy is converted into a useful form.

Abstract: A single chip multiple range pressure transducer device including a wafer having a plurality of simultaneously formed thinned regions. The thinned regions are separated by a fixed portion, and each have a same minimum thickness. The thinned regions have at least one different planar dimension. A plurality of piezoresistive circuits are formed on the wafer. Each of the circuits is associated with and at least partially formed above one of the thinned regions. The thinned regions deflect a different amount upon application of a common pressure thereto, whereby, when excited each of the circuits provides an output indicative the common pressure over a different operating range when the associated thinned region deflects.

Abstract: A control circuit for a piezo transformer based power supply includes oscillator circuitry, drive circuitry, sense circuitry, and feedback circuitry collectively operating to regulate an operational parameter of the supply, such as the current supplied to a cold cathode fluorescent lamp (CCFL). The feedback circuitry includes initialization circuitry that establishes an initial value of an oscillator control signal corresponding to an initial operating frequency, and thereafter permits the feedback circuitry to gradually drive the oscillator control signal to a normal operating value such that the operating frequency is swept from the initial operating frequency to a normal operating frequency. When controlling the power supplied to a CCFL, the initial operating frequency is preferably a maximum frequency of the oscillator, and the operating frequency is swept downward so as to pass through the frequency at which the lamp “strikes”, or begins conduction, and thereafter into regulation.

Abstract: In an internal combustion engine, the fuel reaches a combustion chamber via at least one fuel-injecting device. The fuel-injecting device includes a piezo actuator. The drive energy (U), which is necessary for a specific stroke (h) of the piezo actuator, is determined from at least one function (34 to 40) which couples the stroke (h), the drive energy (U) and the drive time (t) of the piezo actuator with each other. In order to more accurately adjust the stroke of the piezo actuator, it is suggested that a function (34 to 40) be used for the determination of the drive energy (U). These functions (34 to 40) were previously determined for a typical collective load (L1, L2) to which a piezo actuator is subjected.

Abstract: An advantageous combination of preamplifier electronics and circuits for acoustic beam forming with ultrasound transducer arrays permits integration of the electronics and transducer(s) at close distances in a compact arrangement and is operable from an ultrasound imaging or measurement system using only a minimal number of connecting electric wires. To achieve dynamic focusing of the receive beam with a transducer array, an integrated electronic circuit mounted in close proximity to the transducer array provides preamplifiers for the individual elements and delay circuits that are automatically switched in a predetermined time sequence after transmission of an imaging pulse. When a high voltage pulse is transmitted via the cable, a breakthrough circuit connects the cable to the transducer for transmission of the ultrasound pulse, while in receive mode the low level signal on the transducer is amplified and fed as a higher level signal via the same cable to the imaging or measurement instrument.

Abstract: A piezoelectric transformer includes a piezoelectric unit. The piezoelectric unit includes a plurality of driver units divided by at least one groove extending in the longitudinal direction of the piezoelectric unit from one end thereof, and also includes a plurality of generator units, opposing the driver units, divided by at least one groove extending in the longitudinal direction of the piezoelectric unit from the other end thereof. Opposing pairs of the driver units and the generator units constitute a plurality of transformer units. The transformer units differ in length from one another.

Abstract: The pre-treatment method for an electromechanical transducer is particularly suitable for polarizing a piezoelectric actuator for an injection system of an internal combustion engine. Prior to the actual operation, the transducer is actuated with an electrical pre-treatment signal, in order to set a predefined operating point in accordance with the pre-treatment signal. The pre-treatment signal corresponds substantially to the electrical actuation signal during normal operation of the transducer, in order to prevent a displacement of the pre-set operating point during normal operation of the transducer.

Abstract: The invention relates to a piezoelectric motor having a rotor and supply means (S0, S1) for supplying an electrical control voltage to at least one piezoelectric element (9) of the stator. According to the invention, the supply means (S0, S1) are arranged to supply an electrical control voltage having a DC component (V0) for shifting towards the expansion state of the piezoelectric elements (9).

Abstract: A surface acoustic wave filter device has a balance-unbalance conversion function and substantially equal input impedance and output impedance so as to increase out-of-passband attenuation. The surface acoustic wave filter device includes an unbalanced signal terminal, first and second balanced signal terminals, and first and second surface acoustic wave filters having input and output impedances. In each filter, one of the input and output impedances is approximately four times the other impedance. Additionally, 2n−1 first surface acoustic wave filters are connected between the unbalanced signal terminal and the first balanced signal terminal, and 2n−1 second surface acoustic wave filters are connected between the unbalanced signal terminal and the second balanced signal terminal, where n is an integer of 1 or more. The second surface acoustic wave filters are 180 degrees out-of-phase with respect to the first surface acoustic wave filters.

Abstract: A vibrating gyroscope includes a piezoelectric vibrator and a plurality of detection load-impedance elements. The resistance of one of the detection load-impedance elements is changed by a switch so that the resistance is different from that of the other one of the detection load-impedance elements, thereby making difference between the amplitude of signals input from two detection electrodes to a differential circuit and detecting the variation in a Coriolis signal. Accordingly, a self-diagnosis for the vibrating gyroscope, for example, a diagnosis of a short circuit in the detection electrodes of the vibrator can be performed.

Abstract: Multiple outputs can be efficiently generated in a piezoelectric transformer by utilizing both surfaces of a piezoelectric member at the primary side, and the piezoelectric member at the primary side is polarized in the direction of thickness or in the direction of length. The piezoelectric members at the secondary side applied with a polarization in the direction of thickness or in the direction of length are laminated on both surfaces of the piezoelectric member at the primary side in the direction of thickness or in the direction of length. When an alternating voltage is applied to the input terminals at the primary side, thickness vertical vibration is generated at the piezoelectric member at the primary side. The vertical wave vibration that propagates in the direction of thickness propagates to the piezoelectric members at the secondary side, and generates an alternating voltage by a piezoelectric positive effect.

Abstract: A piezo actuator drive circuit (100) adapted to be calibrated in a voltage mode. The present invention achieves technical advantages as a piezo actuator driver that can be calibrated in the voltage mode by switching a drive amplifier (42) output to a high impedance state and driving a load Cpiezo with a fixed current source (Iref) to characterize the load. Preferably, feedback resistors (R1, R2) configured as a resistive divide network are used as a sensor feeding and analog to digital converter.

Abstract: A reciprocating fluid pump includes a drive section and a pump section. The drive section has a pair of coils which may be energized to cause displacement of a reciprocating assembly. Each coil is a reluctance gap arrangement in which a magnetic circuit is interrupted by a gap towards which an armature of the reciprocating assembly is drawn when energizing current is applied to the coil. The reciprocating assembly includes an element which is extended into and retracted from a pump chamber during its reciprocating motion, causing fluid to be drawn into and expelled from the pump chamber. The pump is particularly well suited for use in cyclic pumping applications, such as internal combustion engine fuel injection. Cycle times in such applications may be reduced by appropriate control of the current waveforms applied to the coils.

Abstract: An identification device having a piezoelectric sensor array is used to obtain biometric data. In one embodiment, a piezo ceramic sensory array is used to obtain biometric data. In another embodiment, a multi-layer sensor array structure having a PVDF layer in between two conductor grids orthogonal to one another is used to obtain biometric data. Urethane can be added to one side of the senor array where a finger is placed. A foam substrate can be used as a support. Multiplexers are switched to control the sensor. The device has several operating modes for obtaining a variety of biometric data, including an impedance detection mode, a voltage detection mode, an imaging mode, and a Doppler-shift detection mode. The presence of a fingerprint on the sensor can be used to turn-on the device. The device is capable of capturing a fingerprint, forming a three-dimensional map of a finger bone, and/or determining the direction and speed of arteriole and/or capillary blood flow in a finger.

Abstract: A lamp electronic ballast with a piezoelectric cooling fan. Use of ballast-driven lamps is limited in some lighting applications by thermal considerations. For example, the problem of heat removal from compact fluorescent lamps with integrated ballasts has limited their use. Similarly, the use of ballast-driven fluorescent lighting in high hat and other closed luminaire applications has been limited by thermal considerations. Thermal management of ballasts for such thermally sensitive applications is provided by a piezoelectric fan integrated with the ballast. The power to drive the fan may be obtained from the same AC line input that supplies the ballast, or from an AC ripple voltage present at the output of a rectifier in the ballast, or from the output of the ballast to the lamp, or from any suitable circuit location in the ballast. The fan maybe a membrane-type spot-cooler comprising a thin membrane carried by a frame mounted adjacent a hot spot.

Abstract: A piezoelectric ceramic composition in which the dielectric constant, the mechanical quality factor Qm and the electromechanical coupling factor Kp are superior, and a high power output piezoelectric transformer made of it are disclosed.

Abstract: The output impedance of a piezoelectric transformer defined as a value obtained by dividing the output current at a load resistance of about zero into the output voltage at a load resistance of about infinity is set to be larger than about one-third of the maximum impedance of a discharge tube during discharging. Further, the absolute value of the gradient of the characteristic curve of the piezoelectric transformer is set to be smaller than the absolute value of the gradient of the output characteristic curve of a discharge lamp.

Abstract: To carry out speed control of an ultrasonic motor driven by a self-excited oscillation circuit utilizing the ultrasonic motor per se as a vibrating body and promote reliability of the self-excited oscillation circuit, an instruction signal for controlling a state of the self-excited oscillation circuit constituting a drive circuit, is set in a range capable of stably driving the ultrasonic motor in an aimed state. The self-excited oscillation circuit can be controlled to be brought into a drive state or a stop state in accordance with a drive command signal or a stop command signal from a control signal generating circuit and the control signal generating circuit is set such that a length (TD) of the drive command signal becomes longer than a time period (t1) from when the drive command signal is applied to the self-excited oscillation circuit until oscillation is started.

Abstract: The use of newly discovered chemical reaction products, created when reactants combine to form products on the surface of a catalyst, to generate electricity, beams of radiation or mechanical motion. The invention also provides methods to convert the products into electricity or motion. The electric generator consists of a catalyst nanocluster, nanolayer or quantum well placed on a substrate consisting of a semiconductor diode, and a semiconductor diode on the surface of the substrate near the catalyst. The device to generate mechanical motion consists of a catalyst nanocluster, nanolayer or quantum well placed on a substrate, and a hydraulic fluid in contact with the non-reaction side of the substrate, with the surfaces of both the catalyst and substrate mechanically formed to enhance the unidirectional forces on the fluid. Both devices use a fuel-oxidizer mixture brought in contact with the catalyst.

Abstract: An actuator using an electromechanical transducer capable of driving efficiently and at high speed and a drive pulse generating apparatus, in which the frequency f of a drive pulse is set in a range satisfying equation (1) and the wavelength T is set in a range satisfying equations (2), (3) and (4); (1/3)fr<f<(2/3)fr  (1) 0.4<(T1/T)<0.8  (2) 0.35<(T2/T1)<0.95  (3) 0<(T3/T2)<0.3  (4) where fr: resonance frequency of an oscillating member including the electromechanical transducer, T1: drive pulse width, T2: width of a gradually changing portion of drive pulse voltage, T3: width of a rapidly changing portion of drive pulse voltage and where 0.1<(T3/T2)<0.3 may be satisfied.

Abstract: A smart material control system and related method is disclosed for adaptively controlling the movement of an adaptive structure. The adaptive structure includes a smart material layer bonded to a conductive substrate in a bimorph configuration. A charge projector, such as an electron gun, is utilized to project charges onto the smart material layer of the adaptive structure. A voltage/charge source adaptively controls the potential of the conductive substrate. Depending on the placement of the projected charges and the adaptively controlled potential of the conductive substrate the displacement/curvature is precisely controlled. In an alternate embodiment, two smart material layers are bonded together to form an adaptive structure controlled independently in the x- and y- directions. Also, an array of charge projectors and/or conductive substrate sections may be used to provide varying and broad control of adaptive structures.

Abstract: A valve for controlling fluids which, for its actuation, is provided with a fluid-filled coupling chamber which can be brought to high pressure by virtue of the fact that the valve is disposed between an actuator piston of a piezoelectric actuator and a piston that actuates a valve member and it is used for force and path transmission. To compensate for a leakage in the coupling chamber, a filling valve is provided, which is disposed on the piston that actuates the valve member and is switched by this piston with each stroke of the device. In this manner, the coupling chamber contains a largely constant volume and can also compensate for slight fill level changes caused by temperature differences. The valve is designated for use in fuel injection devices for internal combustion engines of motor vehicles.

Abstract: A variably sound-absorbing device comprises a piezoelectric material 32 the peripheral portion of which is fixed to a frame 31 or the like, at least one pair of electrodes 34 formed on opposite surfaces of the piezoelectric material, and at least one circuit element 36 through which the electrodes are connected to each other. The piezoelectric material 32 is boardlike and curved, and an electrical characteristic of the circuit element 36 (a circuit showing a negative capacitance for example) is variable. The modulus of elasticity (the real number part of the modulus of elasticity) and the loss factor (the imaginary number part of the modulus of elasticity) of the piezoelectric material are thereby varied and the sound-absorbing characteristic is electrically varied to a considerable extent.

Abstract: This invention relates to a vibration wave motor which obtains a driving force by vibrating an elastic member upon application of a frequency signal to a piezoelectric element arranged in the elastic member. Especially, there is provided a motor of this type, which incorporates a capacitance or inductance as an external member required for driving the motor in a motor alone by integrally stacking the member on the elastic member.

Abstract: An apparatus for suppressing print quality degradation due to vibrations in a printing machine structure. The apparatus comprises a vibration member having a structural resonance, a transducer, and means for damping vibrations. The transducer is mounted to the vibration member and produces electrical signals corresponding to mechanical vibrations of the vibration member. The damping means is connected across the transducer and is responsive to the electrical signals.

Abstract: A circuit (10) for driving a piezoelectric transformer (12) in a phase locked mode without using an external reference signal. The circuit (10) utilizes a 555 timer circuit operated in a stable mode which is responsive to a feedback phase signal (18) coupled from an output signal (20) of the piezoelectric transformer (12). The feedback phase signal (18) overpowers the trigger circuit of the timer to phase lock the timer to an output of the piezoelectric transformer (12) at a resonant frequency of the piezoelectric transformer (12). The circuit (10) provides a simplified phase lock circuit without the need for a typical PLL configuration.

Abstract: A lead terminal connection structure of an electroacoustic transducer comprises a lead terminal member having a pair of lead terminals integrated via a bridge piece. The lead terminals have solder surfaces to be soldered to the surface of a circuit board of another device on which an electroacoustic transducer is to be installed. When the lead terminal member is attached to a circuit board of the electroacoustic transducer and the bridge piece is cut, the pair of lead terminals become separate from each other.

Abstract: A cold cathode tube is used for a back light illuminating a liquid crystal with a light from the back. A ceramic transformer is used instead of a conventional wound transformer for a power source to light this cold cathode tube to eliminate various problems caused by transformers. The output voltage and current of this ceramic transformer are coordinated with the cold cathode tube by utilizing the frequency characteristic of the boosting ratio of the ceramic transformer to light the cold cathode tube and adjust the light. The output from an oscillator is amplified and is applied to a ceramic transformer. The output frequency from the oscillator is swept from the higher side to the lower side. When the output frequency decreases from fa.fwdarw.fb, the output voltage of the ceramic transformer in the case that the load resistance indicated by the solid line is large will be Vb and the cold cathode tube will be lighted.

Abstract: The present invention relates to a method for driving an ultrasonic motor of the type which includes a vibrator for causing a flexural vibration wave in response to a pair of AC driving voltage signals, and a rotor in contact with the vibrator and moved by the flexural vibration wave. The rotational speed of the ultrasonic motor is controlled by using a feedback signal and a data table, the feedback signal indicating the current rotational speed of the ultrasonic motor, and the data table storing values of the feedback signal as a standard function of the rotational 21 speed. The method includes the step of sampling the feedback signal and detecting the rotational speed in a plurality of rotation states of the ultrasonic motor. The method obtains an approximate function representing the relationship between the sampled feedback signal and the detected rotational speed of the ultrasonic motor, and calculates correction coefficients for adjusting the approximate function to the standard function.

Abstract: The invention provides a controlling device which comprises a control box, a power box, a right sensor control unit attached to a plurality of proximity detectors, a left sensor control unit attached to a plurality of proximity detectors, and a valve box control unit, wherein each proximity detector comprises an ultrasonic transducer, a first circuit for handshaking, noise reduction and voltage regulation, and a second and third circuit for digital signal generation, analog reception and digital conversion, wherein the first circuit is connected between a left or right sensor control and second and third circuits of a proximity detector.

Abstract: A thread tension adjusting apparatus, used in a sewing machine, adjusts tension of a supplied thread by adjusting a thread holding force. The apparatus is provided on a thread supply path running from a thread source to a thread processing section such as a needle and a looper. The thread tension adjusting apparatus comprises a pair of members respectively having portions opposed to each other. At least one of the members is a piezoelectric actuator for changing a distance between the portions when being driven, whereby to adjust a thread holding force.

Abstract: A thread tension adjusting apparatus, used in a sewing machine, adjusts tension of a supplied thread by adjusting a thread holding force. The apparatus is provided on a thread supply path running from a thread source to a thread processing section such as a needle and a looper. The thread tension adjusting apparatus comprises a pair of members respectively having portions opposed to each other. At least one of the members is a piezoelectric actuator for changing a distance between the portions when being driven, whereby to adjust a thread holding force.

Abstract: An apparatus for driving a printing head of a wire-dot printer, the head including a plurality of electroexpansive elements for driving respective printing wires cooperatively constituting a wire-dot matrix and in accordance with print pattern data designating the existence, or non-existence, of a dot to be printed by the respective, plural dot-impact printing wires in each of a succession of print cycles. Each electroexpansive element, selectively, is expanded and shrunk by an electrical charge/discharge, thereby to move the respective printing wire and perform a dot printing operation. The time intervals T1 and T2 respectively for the charge and discharge in each of a succession of printing cycles are: in the case of continuous dots, T1=A, T2 -B' for the first dot, T1=A', T2-B' for successive dots intermediate the first and the last dots, and T1=A', T2-B for the last dot of the continuous dots, and in the case of a single dot, T1=A, T2=B, wherein A>A', and B>B'.

Abstract: A cointegrated high frequency oscillator including a thin film resonator and active devices formed on the same semiconductor substrate and by a process which is compatible with formation of both the thin film resonator and the active devices. The processes utilized in formation of the thin film resonator are adapted to microelectronic processing techniques such that the steps of formation of the active devices and the thin film resonator can be intermixed to the degree necessary to allow, for example, the metallization layers to serve as elements both of the active devices and the thin film resonator.

Abstract: The humidity within a controlled chamber is detected with a humidity detector, the proportional value, integrated value and differentiated value of the difference between the detected signal and a preset objective value signal are added to be an operation amount signal and an oscillator of an ultrasonic humidifier is oscillated with an amplitude adjusted in response to this operation amount signal to keep the humidity within the controlled chamber constant.

Abstract: The invention relates to a method of and a device for simultaneously generating heat energy and oscillation energy. In the method heat is generated by induction heating and oscillations are created by means of at least piezoelectric elements. Previously a resonance circuit formed by a series connection of an inductive component and a capacitive, piezoelectric component has been used for the generation of oscillations only. A disadvantage of this kind of circuit has been that the circuit is difficult to control on account of the narrow resonance region of the piezoelectric element. This advantage is avoided in the solution according to the invention in such manner that one and the same resonance circuit formed by a series connection of an inductive and capacitive element generates both heat energy and oscillation energy.

Abstract: Wide-band network for matching a signal-conducting line having a characteristic impedance of 50 ohms to a piezoelectric transmitter having a capacitance C.sub.o and a reactance X.sub.o for a center frequency f.sub.o of the frequency band to be transmitted. Various circuit arrangements and dimensioning rules for the circuit elements are specified as a function of the reactance X.sub.o. The transmitter is a part of an acoustic lens arrangement.

Abstract: A signal isolator has an acoustic transmitting medium with a first pair of acoustic transducers thereon for transmitting an input signal through the medium at a first frequency. A first transmitting and receiving circuit is used in combination with the first pair of transducers. A second pair of transducers is located on the acoustic medium to transmit a power supply signal through the medium at a second frequency. Power supply means associated with the power supply signals are used to energize the transmitting and receiving means on opposite sides of the medium.

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: Special low inductance switchable coupling means are provided to permit selective matching of the various segments of the ultrasonic transducer.

Abstract: A supersonic transducer including means for detecting its vibrating speed and for changing the frequency of the energizing current in response thereto. This invention utilizes the property that when an electrostrictive vibrator is vibrated resonantly, its dynamic admittance varies depending upon the difference in its stress distribution. The electrostrictive vibrator is divided into portions of large and small stresses to cancel the applied brake currents. Simultaneously, a signal is derived that is proportional to the difference of the dynamic currents so as to provide an effective energization by detecting the resonant frequency of the vibrator in order to automatically adjust the applied frequency of the supersonic transducer.

Abstract: A hand held device for generating ultrasonic vibrations comprises an elongated tubular casing having therein a piezoelectric vibrator element and a generator that develops an electrical signal having a predetermined ultrasonic frequency that excites the piezoelectric vibrator element into ultrasonic vibration. A work tool protrudes from the casing and is vibrationally coupled to the piezoelectric vibrator element by a vibratory rod and the rod transmits the vibration from the piezoelectric vibrator element to the work tool. A cooling system is disposed within the casing and flows a cooling agent through the device to cool both the piezoelectric vibrator element and the generator and the cooling agent is discharged from the device in atomized form through an opening in the work tool.