Abstract: A control system for a progressive wave type ultrasonic motor including an ultrasonic motor driver circuit which supplies driving electric power to an ultrasonic motor and a rotary encoder which is coupled with an output shaft of the ultrasonic motor and generates a pulse signal in accordance with rotation of the ultrasonic motor, comprising a reference clock signal generator which generates a clock signal and a phase locked loop circuit which transmits a control signal to an ultrasonic motor driver circuit based on the clock signal and the pulse signal from the rotary encoder, and controlling the speed of the ultrasonic motor; and a control apparatus, comprising a driving control means which transmits a driving signal to an ultrasonic motor driver in accordance with a command pulse instructing to start driving of the ultrasonic motor and transmits a suspension signal to the ultrasonic motor driver in accordance with the pulse signal from the rotary encoder, and driving the ultrasonic motor intermittently.

Abstract: An ultrasonic motor driver includes a voltage-current phase difference detector for detecting a phase difference between an applied voltage and a current of a torsional vibration piezoelectric element and a phase shifter for adjusting phases of voltages applied to the longitudinal and torsional vibration piezoelectric elements so that the phase difference is minimum. Even if changes in application environment, e.g., an external force or temperature, occur, a rotational speed can be kept stable to drive an ultrasonic motor.

Abstract: A drive circuit for an ultrasonic motor, which comprises a stator for generating a progressive oscillatory wave to an elastic element with the drive of a piezoelectric element and a moving element to be pressurized by the stator and driven with the progressive oscillatory wave, comprises an inductive element which is inserted between a power source and an input of the ultrasonic motor, and a switching element which is connected between one end of said inductive element connected to said input and a ground, and performs switching with a drive frequency of said ultrasonic motor.

Abstract: In a driving device for an ultrasonic motor which includes a stator for generating a travelling vibration wave in an elastic member by the excitation of a piezoelectric member and a rotor pressed into contact with the stator, the rotor being driven by the travelling vibration wave, a drive signal which drives the motor is supplied to the motor through an induction element. A phase difference between signals input to and output from the induction element is measured, and drive of the ultrasonic motor is controlled using the obtained value.

Abstract: A control device for an ultrasonic motor which is suitable for use in controlling the speed of the ultrasonic motor includes an oscillator for generating drive signals of a resonant frequency of the ultrasonic motor; and a drive signal restricting device for turning on and off the drive signals at a fixed duty ratio. The control device further includes a counter in which counted results of the counter are incremented by a first pulse signal whose frequency increases as a target speed of the ultrasonic motor increases, and in which the counted results are decremented by a second pulse signal whose frequency increases as a travel speed of the ultrasonic motor increases; and a duty ratio setting device for causing the duty ratio to increase as the counted results of the counter increase.

Abstract: A driving circuit for a vibration wave driven motor, having a comparator detecting the drive state of the motor, and the drive frequency somewhat increased immediately before the motor reaches the resonance drive state. Also a second comparator is additionally provided for detecting the drive state of the motor at a second frequency higher than the frequency detected by the first-mentioned comparator, and the drive frequency of the motor is retained if the second comparator detects that the motor is driven with the second frequency.

Abstract: A method for driving a supersonic motor includes the steps of driving the supersonic motor by supplying a driving voltage of greater frequency than a resonant frequency (point) to a driving piezoelectric electric element. The driving frequency is decreased when a wave form distortion is not generated in an output signal of an oscillation detection piezoelectric element provided in an elastic body. The driving frequency is increased when a wave form distortion is generated in the output signal of the oscillation detection piezoelectric element.

Abstract: A driving apparatus for an ultrasonic motor comprises a stator that generates progressive oscillating waves in an elastic body by excitation of a piezoelectric body; a mover that is rendered in contact with said stator by a pressing element so that it is driven by said progressive oscillating waves; a device for producing a signal for steady period, which generates a signal for steady driving; a transient period signal generating device, which generates a driving signal for transient periods; and a switching device which is placed between said ultrasonic motor and said both signal generating devices and which selectively switches the connection between said ultrasonic motor and said two signal generating devices so that said driving signal for transient periods is applied to said ultrasonic motor in said transient state, while said steady driving signal is applied to said ultrasonic motor in said steady operation state.

Abstract: An actuator device has a plurality of projections formed in a vibrator, with the projections being in pressure contact with a friction surface of a contact member, and relative movement between the vibrator and the projections is performed by generating vibrations in the vibrator. The actuator device prevents the contact member and the projections from stopping at identical positions in pressure contact with one another at every stop operation of driving by the actuator device to produce projection marks on the friction member, causing wow/flutter and decreasing torque performance.

Abstract: An ultrasonic motor which has a driving circuit monitoring a current flowing through a piezoelectric element of the ultrasonic motor, shaping and amplifying the current, and feeding back as a control voltage to a voltage-controlled oscillating circuit, whose output is used to generate a drive signal for the ultrasonic motor. This ultrasonic motor driving circuit is provided with a rotation halt detector that detects when the ultrasonic motor stops its rotation. According to an output signal of the rotation halt detector, a reference voltage for the rectification and amplification is variably controlled.

Abstract: In a vibration wave motor, during the actuation of the vibration wave motor during which a detection signal from a vibration detecting electro-mechanical energy converting element is unstable or when the driving voltage is low, driving is effected in the open loop mode which does not use the detection signal, and when the detection signal is stable, driving is effected in the mode which uses the detection signal, i.e., the PLL control mode.

Abstract: This invention concerns with a drive circuit for a vibratory-wave motor and, in particular, is to provide a motor drive circuit in which there is provided a voltage variable circuit for automatically varying the voltage applied to the motor to follow up the variation of the frequency of a driving high-frequency signal to the motor, whereby the voltage that affords an optimum drive efficiency in response to the frequency variation is applied to the motor.

Abstract: A driving circuit for a vibration wave motor uses an AC signal supplied to a piezoelectric member provided on a vibration member to cause a travelling vibration wave in the vibration member, thus driving a movable member. The frequency of the AC signal supplied to the piezoelectric member is determined in a first mode in which the frequency is manually selected, or in a second mode in which a particular resonant frequency is automatically selected according to the vibration state of the motor, wherein the operation is automatically switched from the first mode to the second mode upon detection that the AC signal approaches the particular frequency.

Abstract: A vibration wave motor in which a signal for suppressing unnecessary vibration engendered during the driving of the vibration wave motor, besides the driving signal of the motor, is applied to the motor to suppress the unnecessary vibration.

Abstract: A drive control apparatus for an ultrasonic motor having a vibrator with a piezoelectric element and an elastic element. The apparatus comprises a power source for supplying alternating power to the piezoelectric element, a voltage detecting device for detecting a voltage applied to the vibrator, a sensor for detecting a vibrator state signal dependent on vibrating velocity of the vibrator, and a control device for controlling the ultrasonic motor with reference to the vibrator state signal. For automatic resonant frequency tracking control, the control device controls oscillating frequency of the power source to maintain a phase difference between frequency of the vibrator obtained from the vibrator state signal and frequency of the voltage supplied to the vibrator at a predetermined value. For constant velocity amplitude control, the control device controls output voltage of the power source to maintain the vibrator state signal at a predetermined value.

Abstract: An electrostatic drive device includes at least one fixed electrode plate provided on a fixed portion, and at least one movable electrode plate provided on a movable portion resiliently supported on the fixed portion so as to move freely. The fixed electrode plate and movable electrode plate are disposed as to oppose each other in parallel relation, and the movable portion is driven by an electrostatic force produced by applying a voltage across the fixed electrode plate and the movable electrode plate.

Abstract: A method for driving an ultrasonic transducer, intended for use in atomization of liquids, at one of its selected resonance frequencies, by tuning out the capacitance of the ultrasonic transducer by means of an inductor, by sensing the transducer current, by comparing the phases of the transducer driving voltage and the transducer current and by controlling a voltage controlled oscillator for driving the ultrasonic transducer, by means of a phase error signal such that the ultrasonic transducer is driven with a frequency at which the transducer driving voltage and the transducer current are in phase, whereby the transducer driving circuit is locked to a natural resonance frequency of the ultrasonic transducer.

Abstract: An ultrasonic motor driving circuit for driving an ultrasonic motor of the type wherein a progressive wave or standing wave is excited on the surface of a flexible member by applying a frequency voltage to a piezoelectric element of an oscillation member and drives a moving member which is brought into pressure contact with the oscillation member, the driving circuit comprising a register for converting a current flowing through the piezoelectric device to a voltage signal, reference voltage generator for generating a reference potential for rectification and amplification, rectifying amplifier connected to the register for rectifying and amplifying the voltage signal, voltage control type oscillator for generating a frequency signal in accordance with the output of the rectifying amplifier, frequency divider for frequency-dividing the output signal of the oscillator, phase distributor for advancing or delaying phase of the signal of the frequency divider, and booster connected to the phase distributor for am

Abstract: An ultrasonic motor driving circuit has a drive duty generating circuit that intermittently outputs a drive request signal according to the battery voltage, and a drive signal output means that receives the drive request signal to output a drive signal. The drive signal is in the form of bursts with pause intervals, the pause intervals being variable with a change in the battery voltage thereby improving utilization of the battery capacity.

Abstract: A drive circuit for driving a piezoelectric (PZ) stack, in response to an excitation voltage, generates a dimensional strain varying along a sinusoidal waveform in a PZ stack by applying an excitation voltage intermittently to a series connection of the PZ stack and a winding via a first switching circuit, and then releases the charge of the PZ stack intermittently via a second switching circuit. A control circuit controls the first and second switching circuits by generating a first and second drive pulse stream so that the charge voltage of the PZ stack returns to its initial state in a period of the first and second drive pulse streams. The charge stored in the PZ stack is released fully and quickly before the application of the next pulse voltage without the use of a resistor, and the resonance current which flows through the PZ stack is constant, thereby allowing the PZ stack to be fully discharged without requiring an exclusive path.

Abstract: A driving circuit for an ultrasonic motor is disclosed which utilizes a single transformer. A phase shifter frequency-divides the signal from an oscillator by N and generates a plurality of frequency divide signals having different phases. These divided signals are then used to control the driving of the piezoelectric element used to power the ultrasonic motor.

Abstract: The invention is a method for operating a Scanning Probe Microscope (SPM) to provide the capability to eliminate the scanner drift that occurs after the scan area is offset within the range of the scanner. The method disclosed comprises applying an offset that is larger than the desired one and then reducing the offset back to the desired value for scanning. The technique has been found to produce good results for both large and small scans.

Abstract: A vibration wave driven motor comprise a comparator for comparing a resonance frequency of the motor with a power supply frequency and a frequency setter for setting the power supply frequency according to a predetermined algorithm in response to the output of the comparator. The frequency setter is provided with an algorithm which, if the power supply frequency is identified lower than the resonance frequency by the comparator, brings the power supply frequency toward an optimum frequency through a predetermined frequency higher than the resonance frequency.

Abstract: An air damper operating system for vehicle air conditioners with a plurality of ultrasonic motors. An oscillator circuit, phase shifter and feedback circuit control the frequency of an oscillator of a motor. A feedback signal transfer switch, position sensors and a time-division switching circuit operate the motors until they are rotated to predetermined positions.

Abstract: An ultrasonic motor is provided in which a detector will detect the amplitude of a traveling wave generated on the stator. An oscillator approximates frequency of the travelling wave with respect to the resonance frequency of the stator while the amplitude of the traveling wave is decreased. If the oscillator approaches the frequency of the traveling wave to the resonance frequency of the stator, the amplitude of the traveling wave can be maintained against increasing pressure of the increased torque load of the ultrasonic motor.

Abstract: In a scanning device producing an image from data obtained from a nonlinear piezoelectric scanner having an attached end and a free end providing the data from a lateral scanning motion of the free end a distance about a center position as a result of the connection of a changing scan voltage to elecrodes carried by the piezoelectric scanner, a method of making the scanning motion of the free end linear with time and increasing the speed at which the data is provided for producing the image.

Abstract: Disclosed is a piezoelectric actuator driving apparatus in which a piezoelectric element used to operate as an electro-mechanical transducer is suitably charged and discharged so that the piezoelectric element can make a predetermined amount of mechanical displacement. In the apparatus, the energy of electric charge causing expansion of the piezoelectric element is controlled by a plurality of pulse signals. Each of these pulse signals acts to store electric charge having a predetermined amount of energy in a capacitor, so that the amount of electric charge stored in the capacitor increases with the increase in the number of the pulse signals. After the total amount of the energy of the electric charge stored in the capacitor attains a predetermined value sufficient to cause expansion of the piezoelectric element, the electric charge stored in the capacitor is supplied to the piezoelectric element.

Abstract: A vibratory motor is provided with a detecting member for detecting rotational speed of a rotor member and a control circuit for stopping oscillation of a stator member of the motor when the rotational speed of the rotor member becomes less than a predetermined speed. When the rotational speed of the rotor member is less than the predetermined speed, the control circuit stops oscillation of the stator member. When the stator member stops oscillating, slippage is not generated between the rotor member and the stator member and deterioration of the motor due to friction is successfully decreased.

Abstract: A circuit for driving an ultrasonic motor which is driven by being applied with multi-phase alternating voltages comprises: a digital oscillator for providing a signal having a frequency higher than that of said alternating voltages; a frequency divider for dividing the frequency of the output signal of the digital oscillator into a desired frequency to provide a basic clock signal; a plurality of presetting circuits, each of independently presetting a delay time for generating a plurality of delay clocks which are delayed with respect the basic clock by different delay times; a plurality of delay circuits, each connected with a respective one of the delay time presetting means for generating a plurality of different delayed clock which are delay with respect to said basic clock by different periods of delay time in accordance with the preset delay time; and voltage generators which generates multi-phase alternating voltages from the basic clock and plurality of the delayed clocks for applying the multi-phase

Abstract: A driving device for an ultrasonic wave motor provided with:a stator member having an electrostrictive member and a resilient member, and adapted to generate a travelling vibration wave on the resilient member by excitation with the electrostrictive member; anda moving member maintained in pressure contact with the stator member and driven by the travelling vibration wave, comprising:a drive signal forming circuit for forming AC voltage signals for the high-speed drive and the low-speed drive for application to the electrostrictive member;wherein the electrostrictive member is excited into vibration by the AC voltage signal;a switching circuit for selectively switching the AC voltage signals for the high-speed drive and the low-speed drive for application to the electrostrictive member; anda temporary stop circuit for reducing the frequency of the AC voltage signal, supplied to the electrostrictive member, at zero at least once at the switching from the high-speed drive state to the low-speed drive state.

Abstract: At least two vibration detection electro-mechanical energy conversion element areas substantially centered on the antinodes of both the standing waves are arranged between the group of driving electro-mechanical energy conversion element areas. Amplitudes of two standing waves generated upon application of AC voltages to these groups and a time-phase difference between the standing waves can be accurately detected. The amplitudes of the standing waves can be made equal to each other, and the time-phase difference can be set to be .pi./2, thereby obtaining an ideal vibration state of a travelling vibration wave generated in a vibration plate.

Abstract: There is disclosed a vibration wave driven motor, in which, when the motor is driven in a high frequency region distant from the resonance drive state, the variation of frequency is not prohibited in response to the detection of the drive state mentioned above, and the variation of frequency is prohibited in response to the detection of the drive state when the motor approaches to the resonance drive state.

Abstract: An automotive motor-driven device controlling and driving system for controlling and driving the respective ultrasonic linear motors of a plurality of automotive motor-driven devices, such as power seats, power windows and power antenna. The automotive motor-driven device controlling and driving system comprises a power circuit connected to the battery of an automobile, a single ultrasonic oscillator, a plurality of power amplifiers having input terminals connected to the power circuit and the ultrasonic oscillator, and output terminals connected through motor control switches to the ultrasonic linear motors, respectively, and a control unit for controlling the power circuit, the ultrasonic oscillator and the power amplifiers.

Abstract: An electro-expulsive apparatus including at least two superposed, flexible flat, separately jacketed continuous ribbons of metallic electrical conductor disposed within a sealed outer jacket so that portions of said separately jacketed electrical conductors are separable within said outer jacket to create a void when said conductors are energized simultaneously by an electrical current. The disclosure also includes restoring means for returning the separated conductors to rest position and a method of expulsing solid or frangible material.

Abstract: An ultrasonic vibration treatment apparatus comprising an ultrasonic vibration treatment device including an ultrasonic vibrator and an ultrasonic wave transmitter probe, a detecting element opposing the transmitter for applying light to the transmitter and receiving the light reflected from the transmitter, thereby to detect the amplitude of vibration of the treatment device, and a power source controller for reducing the power supplied to the vibrator, or stopping the power supply to the vibrator, in accordance with a detection signal output by the detecting element. The detecting element quickly detects the charges in the amplitude of vibration of the ultrasonic vibration treatment device, said charge in the amplitude representing the charges in the vibration condition of the vibration treatment device from actual driving to idling, or vice versa.

Abstract: An ultrasonic power supply for driving a piezoelectric transducer at its parallel resonant frequency includes a clamped-mode resonant converter for converting direct current to alternating current and a demodulator, a loop filter and a voltage controlled oscillator in a phase locked loop configuration. The power supply also includes a control circuit for adjustably setting and controlling the amplitude of vibration of the transducer, and providing during start-up a ramp start. The power supply, further, includes a control circuit for limiting the maximum permissible current flow to the transducer and the reverse current flow from the transducer resulting from stored mechanical energy. Both control circuits provide feedback signals which control the pulse width modulated operation of the clamped-mode resonant converter and thereby control the voltage amplitude of the alternating current output from the converter.

Abstract: The system uses a tunable inductor in series with the piezoelectric crystal excitation transducer in the probe which has a flux modulation coil. The bias current through this flux modulation coil is controlled by the system. It is controlled such that the inductance of the tunable inductor cancels out the capacitive reactance of the load impedance presented by the probe when the probe is being driven by a driving signal which matches the mechanical resonance frequency of the probe. The resulting overall load impedance is substantially purely resistive. The system measures the phase angle and monitors the power level. The system uses this information to adjust the bias current flowing through the flux modulation coil to maintain the substantially purely resistive load impedance for changing power levels. This information is also used to adjust the frequency of the driving signal to track changing mechanical resonance conditions for the probe at different power levels.

Abstract: In a drive circuit for a vibratory-wave motor, there is provided a changeover circuit for alternately changing over a direction in which a current is supplied to a primary coil of a transformer in response to a frequency signal, a low-voltage power source is used as a power source of the changeover circuit, and a low voltage is boosted by the switching operation of the changeover circuit to obtain a frequency high voltage for driving the vibratory-wave motor.

Abstract: When kick-backs occur on chain saws the cutter bar (36) is subjected to heavy forces, especially in the longitudinal direction. By putting in a piezo-electric crystal (37) at the cutter bar attachment in a place where the forces occur at kick-backs it can be effected that the crystal generates an electric impulse at sudden force changes, while the normally imposed screw powers do not give any signal. In this way it is possible to let the crystal trigger a mechanism (15) which releases the chain brake (14, 15) in an electrical way.

Abstract: An electro-expulsive apparatus including at least two superposed, flexible flat, separately jacketed continuous ribbons of metallic electrical conductor disposed within a sealed outer jacket so that portions of said separately jacketed electrical conductors are separable within said outer jacket to create a void when said conductors are energized simultaneously by an electrical current. The disclosure also includes the method of manufacture.

Abstract: One periodically determines the frequency of the vibrating element for which the absorbed power through the ultrasonic device is at a minimum and for which its efficiency is maximum. One compares this frequency to a previously measured frequency and modifies of one step of a given amplitude the working frequency of the ultrasonic device after a given number of comparisons having for result a frequency difference greater than a pre-established value have been detected.

Abstract: A method of driving an ultrasonic motor having a rotation body (6) which is rotated by travelling waves generated in a vibrator body (3), whereby the drive frequency of the motor is controlled in accordance with the value of an operating parameter such as phase difference between drive current and voltage, such as to maintain the drive frequency at a value which is lower than the antiresonance frequency of the vibrator body (3) and higher than a highest resonance frequency of the vibrator body (3) in a hysteresis loop exhibited by a resonance frequency characteristic of the vibrator body (3). Continuous stable operation is attained, irrespective of the effects of temperature and load changes upon the motor operating characteristics.

Abstract: In a driving apparatus for an ultrasonic motor, which motor has a stator comprising a pair of piezoelectric members for generating travelling mechanical vibrations, the driving apparatus has an oscillator, a phase shift circuit, and delay circuits. By deferring phases of two control signals for two switching devices, there is no fear of dangerous simultaneous turn-ons of the switching devices.

Abstract: A ultrasonic vibration motor comprises a moving member, a vibration member contacted by the moving member, an electrostrictive device provided on the vibration member, a power supply for applying a periodic voltage to the electrostrictive device to thereby vibrate the electrostrictive device and generate a travelling vibration wave in the surface of the vibration member, a device for detecting the phase difference between the voltage applied to the electrostrictive device and the current flowing into the electrostrictive device, and a device for discriminating a variation in the load of the moving member on the basis of the phase difference.

Abstract: A crystal controlled oscillator in which changes in damping are compensated and a method for decoupling the output signal of such an oscillator from damping changes. The damping decoupled oscillator includes a quartz crystal (10), which produces a periodic signal, connected in series with a variable gain amplifier (18) and a variable phase shift circuit (22). Feedback from the output of the variable phase shift circuit is provided to sustain oscillation of the crystal. Unity gain in the loop is maintained by adjusting the gain of the variable gain amplifier in accordance with the DC value of the output signal, provided by a precision rectifier (34). As the DC value of the output signal changes due to changes in damping or energy loss of the crystal, an absolute value circuit (38) responds by providing a phase control signal for adjusting the phase of the periodic signal to compensate for changes in damping.

Abstract: Miniaturized linear and rotary electrostatic motors. The motors are fabricated by disposing a plurality of conductive lands onto insulating substrates and then filling in the spaces between the lands by deposition of an insulating material. A final layer of insulating material is then disposed over each of the entire surfaces containing the lands to form smooth bearing surfaces. The bearing surfaces of two of these elements are placed in contact. In one embodiment, the natural lubrication of the bearing surfaces aids movement. In another embodiment, a special lubricating film is placed between the substrates. Arrangements are made for maintaining alignment of the contacting elements. The lands are selectively energized in a manner to effect movement of one element with respect to the other.

Abstract: A drive network for an ultrasonic probe includes a network operative to apply a pulse to a feedback terminal of a phase comparator substantially simultaneously with the application at the probe of an excitation signal from a source at a predetermined frequency. This insures that at the start-up of the drive network the frequency of the feedback signal to the phase comparator leads the excitation signal also being applied thereto, to cause the excitation signal from the source to increase toward the resonant frequency of the probe, thereby to search for the resonant frequency of the probe.

Abstract: The invention relates to a method for supplying electric power to a transducer for generating sonic or ultrasonic vibrations.It is characterized in that in the automatic control stage, the control device (11) is kept within said command and control loop and, by means of its processor and as a function of the data furnished to this processor and in particular data emitted by the analyisis means (6-8) furnishing the phase displacement (D.sub.f) and the direction (S.sub.

Abstract: An Ultrasonic Piezoelectric Transducer for atomizing fluids oscillates at its free natural vibration in a parallel resonant circuit. Very short energy pulses are transmitted into the parallel resonant circuit to maintain continuously the free vibration. The measuring the time dependant voltage of the transducer, the transducer vibration frequency is tapped off to regulate the supplied pulses and to transmit them in proper phases. Thus, optimal atomizing is guaranteed in spite of changing operating conditions.

Abstract: A vibration wave motor for driving a movable member by a travelling vibration wave generated in a vibration member having an electrostrictive element by applying a periodic voltage to the vibration member, intermittently applies the periodic voltage to the electrostrictive element to reduce a moving speed of the movable member without reducing an amplitude of the periodic voltage.