Abstract: A valve-actuator includes a chamber, a spool that opens and closes connections between ports in the chamber, an actuator including a housing containing a piezoelectric stack having a bore, and a spring contacting the spool through the bore and forcing the stack toward the chamber, the stack expanding and contracting in response to a voltage, the spool moving in the chamber in response to said expansion and contraction.

Abstract: A temperature compensated crystal oscillator is mounted to a board. A quartz resonator includes a quartz chip that generates an oscillation frequency. A resistive element is formed on the quartz chip. A temperature sensor is located closer to the board than the quartz resonator. The compensation part compensates for a change in the oscillation frequency generated by the quartz resonator based on a value of a current flowing in the resistive element and an output of the temperature sensor.

Abstract: The invention relates to a device for compensating influence of temperature on a resonator circuit. The device comprises a resonator circuit and a supply unit for supplying an electric bias signal to the resonator circuit, wherein the supply unit is adapted for adjusting the electric bias signal for compensating influence of temperature on the resonator circuit.

Abstract: An oscillator that includes a movable element formed of silicon, the movable element vibrating by electrostatic force, a stationary element supporting the movable element, a temperature detector located in contact with the stationary element, the temperature detector detecting the temperature of the stationary element, a supporting element joined to a joint surface between the movable element and the stationary element, the supporting element supporting the movable element, the stationary element, and the temperature detector on a surface opposite to the joint surface, a surrounding element contacted with the supporting element, the surrounding element and the supporting element surround the movable element, and electrodes provided on a surface of the surrounding element opposite to a surface of surrounding element contacted with the supporting element.

Abstract: A piezoelectric device has a plate-shaped substrate, a first frame defining a first concave portion at one surface of the substrate, a second frame defining a second concave portion at the other surface of the substrate, a first electrode member provided at one surface of the substrate, a second electrode member provided at the other surface of the substrate, a piezoelectric unit in which a first electrode section of the piezoelectric vibration plate is fixed to the first electrode member by a conductive binder, a cover sealing the first concave portion, and a temperature detection unit in which a second electrode section of the thermistor element is fixed to the second electrode member by a conductive joining material.

Abstract: A vibration actuator driving device includes a plurality of wiring sections and a supply controller. The plurality of wiring sections are disposed correspondingly to a plurality of electrically independent electrodes of an electromechanical conversion element. The wiring sections input driving signals to drive the electromechanical conversion element. The supply controller is capable of independently supplying a driving signal for each respective wiring section.

Abstract: A device for generating controlled vibration in an uncontrolled temperature environment includes a driving circuit that generates a signal having a first frequency and has a temperature-sensitive driving unit, a vibratory element coupled to the driving unit that vibrates at the first frequency according to the generated signal, and a temperature control circuit to control the temperature of the driving unit.

Abstract: A driver, including: a piezoelectric element extending and contracting upon application of an electrical voltage; a driving member having one end secured to the piezoelectric element; a frictionally coupling member, frictionally coupling the driving member; and a drive circuit, connected with a power supply to activate the piezoelectric element at a predetermined period, including: a charge switching element for connecting an electrode of the piezoelectric element with the power supply, a discharge switching element, and a protective resistor arranged in an electric path between the power supply and the piezoelectric element or between the piezoelectric element and a ground point, wherein a resistance value of the protective resistor is set larger than an ON resistance of the switching element but smaller than a value obtained by dividing one half of the drive period of the switching element by a capacitance of the piezoelectric element, in a predetermined period.

Abstract: A MEMS structure having a temperature-compensated resonator member is described. The MEMS structure comprises an asymmetric stress inverter member coupled with a substrate. A resonator member is housed in the asymmetric stress inverter member and is suspended above the substrate. The asymmetric stress inverter member is used to alter the thermal coefficient of frequency of the resonator member by inducing a stress on the resonator member in response to a change in temperature.

Abstract: A drive unit includes a vibration actuator for controlling the piezoelectric element. A control section controls the vibration actuator switchably between a normal operation mode in which the piezoelectric element vibrates at a predetermined frequency to let the vibration actuator output a driving force, and a heating mode in which the piezoelectric element vibrates in a direction perpendicular to a direction of the driving force at a frequency different from the frequency in the normal operation mode to heat the piezoelectric element.

Abstract: An ovenized oscillator package including at least a heater and a crystal package mounted on opposite sides of a circuit board. Vias extend through the body of the circuit board to transfer heat from the heater to the crystal package. Layers of thermally conductive material extend through the body of the circuit board and are in thermally coupled relationship with the vias for spreading heat throughout the circuit board and other elements mounted thereon.

Abstract: The present invention provides a fuel injector, comprising a housing having a sealable injector seat; a fuel injector pin disposed within the housing proximate to the injector seat such that the injector seat may be sealed and unsealed by displacing the fuel injector pin; a resilient element biasing the fuel injector pin in an unsealed direction; a piezoelectric actuator disposed within the housing proximal to the fuel injector pin configured to actuate to force the injector pin towards the injector seat to seal the injector seat; and a thermal compensating unit disposed within the housing proximal to the actuator and configured to compensate for thermal expansion or contraction of a component of the fuel injector.

Abstract: To provide an electromechanical conversion element, a vibration actuator, a vibration actuator driving device, a lens barrel and a camera, which facilitate the achievement of the desired drive characteristics. An electromechanical conversion element comprising: a piezoelectric body having a polarization part polarized in a certain direction; and a plurality of separately formed electrodes on a continuous region of the polarization part.

Abstract: A valve-actuator for a hydraulic valve includes a valve chamber, ports spaced mutually and opening into the chamber, a spool axially located in the chamber for opening and closing hydraulic connections between at least two of the ports as the spool moves axially in the chamber. An actuator includes a housing having mutually spaced surfaces, and a piezoelectric element located in the housing between the surfaces, the element expanding and contracting in response to an electric signal applied to the element. A temperature compensation and motion damping circuit comprising feedback resistors and a thermistor. The spool moves axially in the chamber in response to expansion and contraction of the element.

Abstract: A drive unit includes a control unit for controlling an ultrasonic actuator. The control unit performs switching between a normal operation mode in which the piezoelectric element unit vibrates at a frequency close to a resonance frequency of longitudinal vibration in the lengthwise direction of the piezoelectric element unit and a resonance frequency of bending vibration to let the ultrasonic actuator output a driving force and a heating mode in which the piezoelectric element unit vibrates at a frequency close to a resonance frequency of longitudinal vibration in the thickness direction of the piezoelectric element unit to heat the piezoelectric element.

Abstract: Components of an ultrasonic sensor are contained in a cylindrical casing having an end wall closing one end of the casing. A vibrator such as a piezoelectric element is disposed in the casing in contact with the end wall. An integrated circuit chip that includes a signal generator, a filter device and a temperature sensor is contained in the casing. Vibrations generated in the vibrator are transferred to the end wall that transmits ultrasonic waves. Ultrasonic waves received by the end wall are converted into electrical signals in the vibrator. Frequency of the transmitting signals and a frequency region of the signals to be received are controlled according to the ambient temperature, so that they always coincide with a resonant frequency of the end wall which changes according to the ambient temperature. Thus, high transmitting/receiving efficiency is always realized, irrespective of the ambient temperature.

Abstract: A system is provided for the regulation of temperature of a crystal oscillator, that system having a thermally conductive support disposed upon a substrate and upon which is disposed the crystal oscillator, an array of thermal vias disposed around the crystal oscillator within the substrate, at least one primary heater communicating with the support, a thermal enclosure communicating with the array of thermal vias, and a at least one secondary heater communicating with the enclosure.

Abstract: Disclosed herein is a driving method of a liquid drop ejecting head in which an oscillatory wave is imparted to a liquid accommodated in a pressure chamber using an electromechanical transducer, which is driven by applying a predetermined driving waveform to the electromechanical transducer, thereby discharging a liquid drop from a nozzle to record an image. The driving method comprising: detecting an environmental temperature, and expanding and/or contracting the driving waveform to be applied to the electromechanical transducer, in a voltage axial direction and a time axial direction, in accordance with the detected environmental temperature, and applying the resulting driving waveform to the electromechanical transducer. Also disclosed is adjusting the waveform of a reverberation adjustor portion of the driving waveform, which adjusts a residual oscillation of the liquid, in accordance with the detected environmental temperature.

Abstract: A method for generating a temperature-compensated timing signal that includes counting, within an update interval, a first number of oscillations of a first micro-electromechanical (MEMS) resonator, a second number of oscillations of a second MEMS resonator and a third number of oscillations of a digitally controlled oscillator (DCO), computing a target DCO count based on the first number and second number of oscillations, computing a loop error signal based on the target DCO count and the third number of oscillations, and modifying an output frequency of a temperature-dependent (DCO) timing signal based on the loop error signal. The duration of the update interval may also be modified based on temperature conditions, and the update interval may also be interrupted and the output frequency immediately adjusted, if a significant temperature change is detected. Thus, dynamic and precise temperature compensation is achieved that accommodates constant, slowly changing, and rapidly changing temperature conditions.

Abstract: A MEMS structure having a temperature-compensated resonating member is described. The MEMS structure comprises a stress inverter member coupled with a substrate. A resonating member is housed in the stress inverter member and is suspended above the substrate. The MEMS stress inverter member is used to alter the thermal coefficient of frequency of the resonating member by inducing a stress on the resonating member in response to a change in temperature.

Abstract: A controller for a high-frequency agitation source includes a signal generator to generate a drive signal having a variable duty cycle. The drive signal is used to drive the high-frequency agitation source. The controller also includes a temperature detector to detect the temperature of the high-frequency agitation source. The controller is configured to vary the duty cycle of the drive signal in response to the temperature of the high-frequency agitation source. By varying the duty cycle of the drive signal, the average power supplied to the piezoelectric crystal can be varied while still maintaining a fixed amplitude of oscillation. This allows the temperature of a high-frequency agitator, for example, a piezoelectric crystal, to be controlled.

Abstract: To provide an electromechanical conversion element, a vibration actuator, a vibration actuator driving device, a lens barrel and a camera, which facilitate the achievement of the desired drive characteristics. An electromechanical conversion element comprising: a piezoelectric body having a polarization part polarized in a certain direction; and a plurality of separately formed electrodes on a continuous region of the polarization part.

Abstract: A method for regulating temperature in an enclosure is disclosed. The method involves monitoring a component temperature inside the enclosure. When the component temperature reaches a threshold, the method injects a coolant into the enclosure. The method further involves regulating a flow rate of the coolant by actuating a miniature piezoelectric element to reduce the component temperature to a prescribed level.

Abstract: The present invention relates to a resonator structure, temperature compensation method and temperature control apparatus for controlling local temperature of a resonator structure. At least one heating element (55) is integrated on a substrate of the resonator structure, and a temperature control signal generated based on a stored temperature characteristic is applied to the at least one integrated heating element (55). Thereby, the at least one heating element (55) and an optional integrated sensing element can be provided very close to the resonator. It is thus possible to control or calibrate variations of sensing elements, heating elements and resonator out from every sample.

Abstract: A universal platform for surface acoustic wave (SAW) based sensors uses a selective sensing film coating on a piezoelectric substrate depending upon the application and the measurand to be measured. A SAW substrate with one or more IDTs and associated microcontroller-based electronics with a power supply can be implemented in the context of a common sensor platform. The platform can be mass produced and a selective coating utilized. The selective coatings can be adapted for use in a sensor involving, for example, gas sensing humidity (metal oxide semiconductors, Polymers, Zeolites), pressure, temperature (metal oxides whose conductivity vary with temperature), force, torque, strain, stress and applications associated with a variety of physical parameters.

Abstract: The present invention relates to a piezo actuator driving circuit. The piezo actuator driving circuit includes a pulse generator that generates a first voltage pulse with a constant period; a first driver stage that receives the first voltage pulse of the pulse generator and buffers the first voltage pulse to output; a second driver stage that converts the first voltage pulse, buffered and output in the first driver stage, into a first current pulse to output; a driving voltage maintaining section that is connected to the pulse generator and the second driver stage so as to output a second current pulse for maintaining a constant amplitude of driving voltage pulse; and a piezo actuator that is connected to the second driver stage and the driving voltage maintaining section so as to be charged and discharged by the first and second current pulses and that is driven by the driving voltage pulse with a constant amplitude.

Abstract: An oscillator circuit is provided having an oscillating amplifier circuit connected to a resonator. The oscillator/amplifier and resonator are preferably fabricated on a single die using semiconductor fabrication tools. Included with the circuitry is a temperature sensor or transducer, an execution unit, non-volatile memory, a modulator, and frequency synthesizer, all of which are integrated together on the substrate, along with the piezoelectric crystal resonator. The frequency synthesizer can preferably include a phase-locked loop with a divider that is in a feedback loop of the phase-locked loop, in which a divide-by value is received from a modulator that achieves finer and higher resolution frequency selectivity from the voltage-controlled oscillator, also within the phase-locked loop, as an output from the crystal oscillator.

Abstract: Disclosed is an oscillator that relies on redundancy of similar resonators integrated on chip in order to fulfill the requirement of one single quartz resonator. The immediate benefit of that approach compared to quartz technology is the monolithic integration of the reference signal function, implying smaller devices as well as cost and power savings.

Abstract: An electric motor system includes an electric motor, a temperature sensor mounted therein capable of measuring a local temperature and generating a temperature related signal, and a processor configured to calculate an actual temperature of a rotor magnet from the temperature related signal, and an actual output torque from the actual rotor magnet temperature. A method for determining the actual output torque of a motor includes sensing a temperature within the motor, calculating a rotor magnet temperature from the sensed temperature, and calculating the actual output mechanical torciue from the rotor magnet temperature.

Abstract: A circuit for generating a component of n-th order includes: six differential amplifiers (15A to 15F) having a pair of input terminals supplied with a common linear input signal and a constant level signal of a predetermined level, outputting a reversed or non-reversed signal to the linear input signal, and having a limiter function to limit the output signal to a predetermined maximum value and a minimum value; a constant level signal generation circuit for supplying the constant level signal to each of the six differential amplifiers; a current mirror circuit (14) for controlling current flowing in the differential amplifiers (15A to 15F); and addition resistors (16A, 16B) for adding the output current of the differential amplifiers (15A to 15F).

Abstract: A fragrance dispensing shower head apparatus includes a shower head including proximal and distal end portions and a central bore extending therebetween. The proximal end portion has a threaded inner surface. The shower head further includes a wire-mesh screen traversing water flow such that foreign debris can be sustained upstream of the distal end portion. A mechanism is included for ejecting a quantity of the fragrance into the bore and includes a plurality of reservoirs for holding the fragrance. The reservoirs introduce the fragrance adjacent to the distal end portion and have substantially similar shapes.

Abstract: A device for controlling a piezoelectric actuator (Cp), in particular for a fuel-injection valve of an internal combustion engine, comprises an energy source (EQ), which supplies the actuator (Cp) with energy (E0), whereby the extension of the piezoelectric actuator (Cp) corresponds with a predetermined response to changes in temperature. A compensation capacitor (C0) is connected in parallel to the piezoelectric actuator (Cp). The capacitance of said capacitor is calculated in such a way that the extension (Cp) of the actuator remains approximately constant over the temperature range, when supplied with a constant amount of energy (E0) by the energy source (EQ).

Abstract: The invention relates to the return stroke between an actuator and an element. In order to displace the element the actuator (A) is impinged upon by a control voltage (ANS). The control voltage (ANS) is selected in such a manner that it is dependent on the size of return stroke in order to compensate the alteration in the return stroke.

Abstract: A component having an acoustically active material, whose acoustic constants can be at least partially altered. The acoustically active material is located at least partially at a phase transition point and/or in the vicinity of a phase transition point.

Abstract: Apparatus and methods for exciting a piezoelectric device. A control device receives a first control signal excites the piezoelectric device at about at least one predetermined electrical resonant frequency of the piezoelectric device as a function of the first control signal.

Abstract: A pseudo-cubic function generator circuit comprises a CMOS inverter which is applied with a detected voltage of a sensor and supplied with a power supply voltage, and a voltage divider circuit for dividing the power supply voltage, wherein an output terminal of the CMOS inverter is connected to a voltage division point of the voltage divider circuit to generate an output voltage from the voltage division point. The pseudo-cubic function generator circuit can directly generate a large voltage change in a simple circuit configuration with a reduced noise component, and facilitates a setting of each parameter for specifying a cubic function curve. The parameter is set, for example, by scaling substantial gate areas of a P-MOS FET and an N-MOS FET which constitutes the CMOS inverter.

Abstract: A system for discriminating between coded responses from multiple SAW identification tags and a method of operating such system. In one embodiment the system provides for a SAW tag reader subsystem that detects coded responses from the tags to an interrogation pulse; and a coded response analyzing subsystem, coupled to the SAW tag reader subsystem, that employs signal processing techniques to separate portions of the coded responses and generates possibilities for remaining portions of the coded responses.

Abstract: A smooth impact drive mechanism utilizing an electromechanical conversion element, in which a preheating voltage to preheat the electromechanical conversion element is impressed thereto before the impression of a drive voltage to the electromechanical conversion element, in order to realize stable drive characteristics by reducing fluctuation in the speed of the moving unit. In addition, drive parameters are changed in accordance with the temperature of the electromechanical conversion element. Furthermore, drive parameters are changed in accordance with the moving speed of the moving unit.

Abstract: In a piezoelectric resonator, the temperature coefficient &egr;TC of the capacitance of the piezoelectric material, the bandwidth ratio &Dgr;f/fo, the temperature coefficient FrTC of the resonance frequency, the temperature coefficient FaTC of the anti-resonance frequency, and a target value &agr; for the temperature coefficient of the center frequency satisfy the following expression: |(FrTC+FaTC)/2+K×&egr;TC×(&Dgr;f/fo)|≦&agr; where K=a coefficient determined according to the impedance at the midpoint between Fr and Fa; &egr;TC=A×(the amount of change in capacitance in a measured temperature range)/(the capacitance at a reference temperature×the measured temperature range); &Dgr;f/fo=(Fa at the reference temperature−Fr at the reference temperature)/(fo at the reference temperature); FrTC=A×(the amount of change in Fr in the measured temperature range)/(Fr at the reference temperature×the measured temperature r

Abstract: A controller for a quartz crystal microbalance (QCM) sensor system and method for detecting mass deposition on a QCM sensor. The controller controls a QCM using temperature-, voltage- and current-regulating circuits, a microcontroller, an oscillator, heating and cooling devices and circuits, high voltage grids, digital-to-analog and analog-to-digital converters, data telemetry and uplink circuits, and a remote user. The remote user may be a person, computer, network or data logger. The remote user allows the controller to be reconfigurable during operation. The controller samples and reports data faster and is more reliable over extended periods of operation. Further, the controller is assembled using innovative techniques making it smaller and thus more transportable, easier to incorporate into existing facilities and less expensive to construct and operate. The apparatus may also be assembled in a modular fashion that allows for customization.

Abstract: A crystal oscillator according to the present invention prevents abnormal oscillation at a temperature in a low-temperature area equal to or lower than an ordinary temperature. The crystal oscillator is configured such that a crystal vibrator is made to abut against a heat source, and the temperature of the crystal vibrator can be kept higher than a temperature where abnormal oscillation occurs. The temperature of the crystal vibrator is assumed to be, for example, higher than 0° C. Additionally, as the heat source, for example, a power transistor that amplifies an oscillation output is used.

Abstract: The present invention provides methods and apparatus for controlling an electric field across a piezoelectric device. A temperature determining device transmits a temperature signal indicative of a temperature of the piezoelectric device. A control device receives the temperature signal and a first control signal indicative of a desired displacement of the piezoelectric device. The control device transmits a second control signal to the piezoelectric device as a function of the temperature signal and the control signal. The second control signal creates the electric field across the piezoelectric device, when the temperature of the piezoelectric device is below a predetermined threshold, having a magnitude above a normal operating range for the piezoelectric device.

Abstract: The present invention provides methods and apparatus for controlling an electric field across a piezoelectric device. A temperature determining device transmits a temperature signal indicative of a temperature of the piezoelectric device. A control device receives the temperature signal and a first control signal indicative of a desired displacement of the piezoelectric device. The control device transmits a second control signal to the piezoelectric device as a function of the temperature signal and the control signal. The second control signal creates the electric field across the piezoelectric device, when the temperature of the piezoelectric device is below a predetermined threshold, having a magnitude above a normal operating range for the piezoelectric device.

Abstract: An apparatus and method for stabilizing the frequency of a piezoelectric crystal resonator, especially useful in common emergency positioning radio beacons. A temperature compensated crystal oscillator circuit (TCXO) is mounted on one surface of a thin substrate. The TCXO includes a piezoelectric device such as a quartz resonator and a capacitor thermistor compensation network to reduce the frequency fluctuations of the crystal through variations in temperature. A heating circuit is mounted to the opposing surface of the substrate, thereby providing a thermal connection between the two circuits. The heating circuit includes a temperature sensor for sensing changes in ambient temperatures and a heater control amplifier for adjusting the power of a heating element. The substrate with the two circuits disposed thereon is suspended within a hermetically sealed enclosure by a plurality of support pins.

Abstract: A controller for a quartz crystal microbalance (QCM) sensor system and method for detecting mass deposition on a QCM sensor. The controller controls a QCM using temperature-, voltage- and current-regulating circuits, a microcontroller, an oscillator, heating and cooling devices and circuits, high voltage grids, digital-to-analog and analog-to-digital converters, data telemetry and uplink circuits, and a remote user. The remote user may be a person, computer, network or data logger. The remote user allows the controller to be reconfigurable during operation. The controller samples and reports data faster and is more reliable over extended periods of operation. Further, the controller is assembled using innovative techniques making it smaller and thus more transportable, easier to incorporate into existing facilities and less expensive to construct and operate. The apparatus may also be assembled in a modular fashion that allows for customization.

Abstract: An angular velocity sensor includes first exciters providing a vibrator with drive vibration, a piezoelectric element having a vibration detector for detecting vibration level of the vibrator, and Coriolis detectors for detecting Coriolis vibration depending on an input angular velocity, and including a driving circuit for receiving a signal from the vibration detector and issuing a signal to the first exciters and a detection circuit for receiving signals from the Coriolis detectors. The circuit section further includes a level judging circuit for judging abnormal levels of electric charges in the Coriolis detectors and a fail detector for issuing an output when abnormality is detected. Each output of the Coriolis detectors contains a drive vibration component larger than the reference level of the level judging circuit, and the layout of the electrodes in the element section is adjusted so that combined output may contain the component smaller than the reference level.

Abstract: A control system for temperature compensating a piezoelectric device. The control system includes a temperature compensating circuit that is operable to receive a control signal corresponding to a desired position of the piezoelectric device and compensate the control signal in response to an estimated temperature proximate the piezoelectric device. A piezoelectric device control circuit is operable to receive the temperature compensated control signal and generate a control signal that is adapted to drive the piezoelectric device to the desired position. The temperature proximate the piezoelectric device may be estimated from an estimated ferroelectric polarization of the piezoelectric device or from a temperature sensor.

Abstract: The thermal load of an electrical component is used as a basis to limit an electric current through the electrical component, in particular the rotor winding of a turbogenerator. This reliably avoids overheating of the component and at the same time achieves full exhaustion of the electric current, particularly in the case of field forcing.

Abstract: The invention describes a method and an apparatus for charging a piezoelectric element, for example, used as an actuator in a fuel injection system of an internal combustion engine. The method and apparatus are characterized in that the piezoelectric element is activated by an activation voltage having a value set as a function of manufacturing characteristics of the particular piezoelectric element and based upon, for example, a correction value for injected fuel volume.

Abstract: A crystal oscillator in which IC control terminal electrodes for writing temperature compensation data in an IC chip are formed on side surfaces of a main body while being distanced from the top and bottom surfaces of the main body. The IC control terminal electrodes will not be short-circuited with a conductive pattern for sealing the crystal oscillating element on the top surface, and the IC chip will not be destroyed by a welding current which flows when a metal cover is mounted on the top surface. The IC control terminal electrodes will not be short-circuited with other wiring conductors during the soldering to bond the crystal oscillator to a printed circuit board. The compensation data or other data written in the IC chip can be stably maintained, thereby securing a stable operation.