Abstract: A compact linear bi-directional motor is driven by one or more induced strain actuators, such as piezoelectric actuators, fabricated in its preferred embodiment using MEMS technology and incorporating a plurality of multi-clamps that alternately engage, forced by electrically energized auxiliary actuators, the rails or micro-ridges located on the base of the motor, on which they ride. This function is synchronized with energizing of the main actuator that alternately extends and contracts causing incremental motion of the multi-clamp assembly. An external load can be attached through a shaft to the multi-clamp assembly or the base.

Abstract: The present invention relates to a vibration type actuator or a vibration type driving apparatus that includes a vibration member that generates therein respective vibration displacements in at least three different directions, and a plurality of contact members contacting the vibration member, wherein the respective vibration displacements in the three different directions generate a composite vibration that simultaneously moves selected contact members of the plurality of contact members relative to the vibration member.

Abstract: An actuator scaled to macroscopic or microscopic sizes, uses ultrasonic energy to induce motion of an object in a desired direction. The actuator includes one or more pair of piezoelectric transducers connected with a transducer tip. Supplying the piezoelectric transducers with alternating current electrical power causes the tip to vibrate at ultrasonic frequencies. Urging the vibrating tip into contact with a surface on the object at a selected angle of inclination induces the object to move in the desired direction at a rate determined by the inclination angle. Multiple actuators can be used to induce a fall range of movements of variously shaped objects. In microscopic form, the actuator can be used to create a MEMS device. The optional application of a compliant material either on the transducer tip or on the object's surface enhances the movement induced by the actuator.

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

Abstract: The present invention discloses an electromechanical actuator arrangement (10) and a method for driving such arrangement, having a plurality of drive elements (14a-d) according to a walking mechanism in a motion relative a body (22). A driving portion of the drive elements (14a-d) are independent movable tangentially and normally to the body (22) surface. The drive elements (14a-d) are driven in the fours cycle steps; gripping, moving the body, releasing and returning to the original position. The drive elements (14a-d) are divided into two exclusive sets. The driving of the sets is phase shifted. At least one of the sets is in contact with the body (22) surface at each instant. The present invention is characterised in that the driving of the drive elements (14a-d) during the gripping sequence is performed in such a way that the drive elements (14a-d) have a velocity, which has a significant tangential component.

Abstract: A surface acoustic wave motor with high energy efficiency, which may efficiently execute recovery of energy of surface acoustic waves propagated to the ends of piezoelectric substrate and re-excitation by the recovered energy, includes a comb-shaped electrode having interdigital structure for generating surface acoustic waves and two unindirectional comb-shaped electrodes having interdigital structure for recovering and re-exciting surface acoustic wave energy arranged on a piezoekextric substrate, and a slider disposed between the comb-shaped electrode for generating surface acoustic waves and the unindirectional comb-shaped electrodes for recovering and re-exciting surface acoustic wave energy.

Abstract: A piezoelectric actuator has a rotational moving member and a supporting member disposed opposite to the rotational moving member and having cantilever portions. Each of the cantilever portions of the supporting member has a fixed end and a free end opposite to the fixed end for contacting the rotational moving member when the supporting member is oscillated. A piezoelectric member is disposed on a respective one of the cantilevers of the supporting member. A power source supplies a voltage to each of the piezoelectric members to oscillate the supporting member in a vibration mode higher than a secondary mode of vibration so that the free ends of the cantilevers make sufficient contact with the rotational moving member to thereby rotate the rotational moving member.

Abstract: A piezoelectric motor including a motor body, a compliant layer in communication with the motor body, and a predetermined number of legs in communication with the compliant layer, which urges the legs into engagement with a substrate. Each of the legs includes a piezoelectric wafer, preferably operated in the shear mode. The actuation of a piezoelectric wafer causes the corresponding leg to be displaced relative to a substrate. This displacement results in the transfer of strain energy to the compliant layer. The energy stored in the compliant layer may be released, causing the motor to advance along the substrate. The legs may be capable of moving independently from one another and also may be capable of moving sequentially or in a predetermined groups or units. The legs also may be arranged in pairs with the leg pairs being capable of simultaneous actuation. The motor is capable of maintaining a high holding force in the absence of a power input.

Abstract: In a small rotary actuator having a rotor and a plurality of oscillators, each having a piezoelectric element that is excited by application of energy thereto so that the piezoelectric element oscillates at a resonance frequency thereof, the resonance frequency of the respective oscillators varies to some degree. This variation reduces the efficiency of rotation of the rotor. In order to reduce this variation, one or more of the piezoelectric elements of the oscillators is etched so that its resonance frequency is increased to match the resonance frequency of the other oscillators.

Abstract: An ultrasonic motor composed of a cylindrical stator having a vibration converting member and a cylindrical rotor slidably rotatable on the stator. Ultrasonic longitudinal vibration is generated in the stator by imposing high frequency voltage on piezoelectric elements disposed in the stator. A part of the longitudinal vibration is converted into twisting vibration by operation of slits formed on the vibration converting member. Both the longitudinal and twisting vibrations are compounded into elliptic vibration which drives the rotor. The vibration converting member is made by laminating a number of element plates each having cut-out portions or by combining several divided blocks. The slits are automatically formed on the vibration converting member without being machined, when the vibration converting member is formed by assembling the element plates or the divided blocks.

Abstract: A piezoelectric motor has peak performance at a specific frequency f1 that may vary over a range of frequencies. A drive system is disclosed for operating such a motor at peak performance without feedback. The drive system consists of the motor and an ac source connected to power the motor, the ac source repeatedly generating a frequency over a range from f1−&Dgr;x to f1+&Dgr;y.

Abstract: An ultrasonic motor includes a vibrator vibrating in conformity with a frequency voltage. A relative motion member effects relative vibration in conformity with the vibration of the vibrator. The vibrator is adapted to vibrate in a first vibration mode and a second vibration mode vibrating in a direction differing from the first vibration mode. The resonance frequency of the first vibration mode is higher than the resonance frequency of the second vibration mode.

Abstract: A driving apparatus, employing a piezoelectric element, for smoothly and silently driving a focus lens of a camera over a wide range of its driving speed. The driving apparatus includes a control system for controlling the piezoelectric element in such a manner that a continuous supply of a certain number of drive pulses to the piezoelectric element and a non-supply thereof during a certain period of time are repeated by a “block pulse drive” at time of slow speed driving, and that the continuous supply thereof are continuously supplied to the piezoelectric element by a “continuous pulse drive” at time of high speed driving.

Abstract: A high force linear displacement piezoelectric motor operates with equal force and reliability in both the push and pull mode. The new motor includes a split motor shaft having with two shaft segments that are coaxially affixed to opposite sides of an expandable and contractable displacement actuator. The displacement actuator has a piezoelectric body coincident with the axis of the shaft segments such that the expansion of the piezoelectric body increases the length of the split motor shaft. The motor has a set of clamps that receive and close on the shaft segments to hold them in place, or open to allow axial displacement of the shaft segments. Linear motion of the split shaft motor is produced by coordinating the opening and closing the clamps with the expansion and contraction of the piezoelectric body.

Abstract: An ultrasonic actuator to suppress or eliminate pitching vibration arising in a vibration element when driving the ultrasonic actuator and to increase driving efficiency and reduce noise. The ultrasonic actuator includes a vibration element; an electromechanical conversion element mounted on the vibration element to generate a drive force in the vibration element by excitation of the electromechanical conversion element; drive force output members to extract a drive force obtained by excitation of the electromechanical conversion element; a relative motion member in contact with the drive force output members and driven in relative motion with respect to the vibration element by the drive force; a base member; and a fixed member to fix the vibration element to the base member.

Abstract: A piezoelectric stepping motor comprises a cylindrical housing (1), a stator and a rotor (4). The stator comprises at least two rotary-fixing (2) and fixing (3) piezoelectric units which are located one behind the other in a longitudinal plane. The piezoelectric unit (2) comprises a rotary piezoelectric cell (5) and a fixing piezoelectric cell (60, insulators (7) and a friction element (8). The piezoelectric unit (3) comprises a fixing piezoelectric cell (9), insulators (7) and a friction element (8).

Abstract: A piezoelectric motor of a linear contact type contains one or more actuators placed about a rotor. Each actuator contains at least one piezoelectric vibrator with a working end urged against the rotor. Periodic oscillations of each vibrator cause compressions of the rotor not exceeding its natural elastic compression limit so after its compression the rotor fully restores its initial cylindrical shape. Such elastic compressions ensure longer operational life of the motor. In another embodiment, each actuator has a laminated design with at least two vibrators separated by an isolator. The isolator extends beyond the vibrators and has appropriate hardness to engage with the rotor. A rotor of laminated design is also described to achieve the optimum hardness relative to the hardness of the actuators. The hardness of the vibrator is about 5×107 N/cm2 and much higher than the hardness of the rotor being about 2×106 N/cm2.

Abstract: A piezoelectric linear stepping motor comprises a housing (1), a movable part (4); between them there are provided fixing units made in the form of two piezoelectric units: a shifting-and-fixing unit (2) and a fixing unit (3) which consist of piezoelectric cells (7,8,9), insulators (5) and friction elements (6), the movable part (4) being in contact with the friction elements (6).

Abstract: An apparatus comprises first and second piezoelectric elements 25a, 25b each extending and contracting in a driving direction, a fixed member 32 secured to one end of each of the first and second piezoelectric elements 25a, 25b, first and second guide shafts 28a, 28b secured to the other ends of the respective first and second piezoelectric elements 25a, 25b to reciprocate with the extension and contraction of the aforesaid piezoelectric elements, first and second lens frames 21a, 21b held frictionally by the first and second guide shafts 28a, 28b, and a drive pulse generator for causing the slow and rapid displacements of each of the first and second piezoelectric elements 25a, 25b and outputting drive pulses such that a period during which the first piezoelectric element 25a undergoes rapid displacement does not coincide with a period during which the second piezoelectric element 25a undergoes rapid displacement.

Abstract: An ultrasonic motor comprises first piezoelectric oscillators alternately arranged with first polarized regions having a first direction of polarization and second polarized regions having a second direction of polarization opposite to the first direction of polarization. The first piezoelectric oscillators undergo bending vibration in a first direction upon input of drive signals having a same phase to the first polarized regions and the second polarized regions to thereby excite the first and second polarized regions. Second piezoelectric oscillators are laminated to the first piezoelectric oscillators in a second direction generally perpendicular to the first direction for undergoing elongation and contraction vibration in the first direction.

Abstract: A vibration device has a vibration member for exciting vibration by supplying power to the vibration device. A signal supply member for sandwiching the vibration member such that the vibration member can be elastically deformed supplies a driving electric signal to the vibration member.

Abstract: An ultrasonic motor has a vibrating member vibrationally driven for undergoing periodic vibration by the application of a high-frequency voltage. A moving body is frictionally driven by the periodic vibration of the vibrating member. A node supporting/pressurizing member supports a vibration node of the vibrating member and presses the vibrating member on the moving body.

Abstract: A piezoelectric stepping motor comprises a cylindrical housing (1), fixing units and a movable part (4). The fixing units comprise at least two rotary-shifting-fixing piezoelectric units (2,3) which are arranged one behind the other in a longitudinal plane. Each piezoelectric unit (2,3) comprises a rotary piezoelectric cell (5), a shifting piezoelectric cell (6), a fixing piezoelectric cell (7) and a friction element (9) separated by insulators (8).

Abstract: A vibration motor includes a stator and a rotor and excitation arrangements for deforming the stator in vibratory modes combining tangential vibrations and normal vibrations intended to drive rotation of the rotor. The rotor and the excitation arrangements have dimensions such that the normal and tangential modes have similar resonant frequencies, or even the same resonant frequency, and correspond substantially to the excitation frequency.

Abstract: In a truss type actuator having two piezoelectric devices provided for crossing at right angle and driven by two alternating driving signals having a predetermined phase difference between them for driving a chip member along a predetermined elliptic trail (including a circular trail). The piezoelectric devices are contacted by protrusions having a high rigidity and formed on contacting faces of the chip member and a base member for holding the piezoelectric devices, and fixed by adhesive having a low rigidity and filled around the protrusions. Thereby, one of the piezoelectric device hardly receives a reaction force from another piezoelectric device due to the displacement thereof.

Abstract: A driving apparatus includes an electromechanical transducer that is connected to a drive pulse generating means and that expands and contracts, a driven member that is connected to one end of the transducer, a friction member that is connected to the other end of the transducer and a guide unit that is in frictional contact with the friction member. The friction member has an elastic deforming mechanism that elastically presses against and comes into frictional contact with the guide unit, and the elastic deforming mechanism is constructed such that its elastic deformation stress vector perpendicularly crosses the directions of expansion and contraction of the transducer.

Abstract: The invention relates to an antenna-switching device between the output of a transmitting stage and the input of a receiving stage, which includes a piezoelectric actuator formed by two fixed plates (21, 22) which form a capacitor and a movable contact (23) of a piezoelectric material. The inside surfaces of the plates are locally metallized for forming electrical contacts. Electrodes are provided for applying to the movable contact a control voltage capable of deforming the contact. The deformation occurs between a rest position corresponding to a given part of the plates and a working position corresponding to another given part of the plates.