Abstract: A driving apparatus of the invention comprises a fixed member, a piezoelectric element fixed at one end to the fixed member, and a driving friction member fixed to the other end of the piezoelectric element. The driving apparatus of the invention is arranged to move a movable unit which is slidably mounted on the driving friction member by expansion and contraction of the piezoelectric element. Herein, a bonded surface of the piezoelectric element to the driving friction member is included in a bonded surface of the driving friction member to the piezoelectric element.

Abstract: A rectangular vibrating plate 10 in which a piezoelectric element and a reinforcing plate are stacked is supported on a main plate by a support member 11, and is urged toward the rotor 100 by an elastic force of the support member 11. This brings a projection 36 provided on the vibrating plate 10 into abutment with an outer peripheral surface of the rotor 100. In this construction, when the vibrating plate 10 vibrates in the horizontal direction in the figure by an applied voltage from a driving circuit (not shown), the rotor 100 is rotated in a clockwise direction in accordance with the displacement of the projection 36 due to the vibration.

Abstract: A system having a harmonic frequency actuator system is provided including providing an actuator body, the actuator body having more than one set of fingers for generating a motion for a semi-rigid element, and attaching a high frequency actuator to the actuator body forming a harmonic frequency actuator to provide motion at predetermined frequency pairs.

Abstract: A piezoelectric motor comprising: a piezoelectric vibrator having an axis of symmetry and a first vibration mode, which when excited generates oscillatory motion of mass points in the vibrator parallel to the axis of symmetry; and at least one friction nub having a center of mass displaced from the axis of symmetry, as a result of which displacement, when the vibration mode is excited, torque is generated on the vibrator that excites a second vibration mode of the vibrator.

Abstract: A piezoelectric motor that allows movement of an arbitrary object in an arbitrary direction is described. The piezoelectric motor includes at least two piezoelectric drives positioned to direct energy at an angle to each other. A contact element translates the energy from the piezoelectric drives to an object, thereby moving the object in the desired direction.

Abstract: The present invention comprises a first vibrator comprising a piezoelectric unit and at least one driving contacting part which vibrates by applying a predetermined voltage thereto, a second vibrator which comprises a piezoelectric unit and a plurality of driving contacting parts which vibrate by applying a predetermined voltage thereto, a pressing component which relatively presses the opposing parts of both the first vibrator and the second vibrator, and a driven component which is sandwiched between the first and second vibrators, in contact with the driving contacting part of the first and second vibrators which are pressed by the pressing component, and supported to enable movement with respect to the first and second vibrators in the long-side direction perpendicular to the direction relative to the opposing part.

Abstract: Detection electrodes 82D and 82E are formed at positions that include an antinode of a flexural oscillation mode. The strain of flexural oscillation reaches a maximum and the effects on the phase difference in the longitudinal oscillation mode can be cancelled out. The detection electrodes 82D and 82E are formed at the positions of drive electrodes 82B and 82C used to excite the flexural oscillation mode. A phase difference in the flexural oscillation mode opposite in sign relative to the longitudinal oscillation mode is created making it is easy to classify based on the phase difference between a frequency at which the longitudinal oscillation mode is dominant and a frequency at which the flexural oscillation mode is dominant. Thus, reliable control can be achieved based on the oscillation behaviors at each frequency ensuring a satisfactory drive force based on oscillation in the longitudinal oscillation mode.

Abstract: When starting a vibration-type drive device, the frequency of a drive signal is lowered from a predetermined frequency at a first change rate. When the vibration state of a vibration member reaches a predetermined state, it is determined whether or not a relative movement speed has reached a reference speed. When the relative movement speed has not reached the reference speed, the frequency of the drive signal is lowered at a second change rate that is smaller than the first change rate. This avoids problems which could occur when moisture intervenes on a slide surface of the vibration-type drive device, such as the vibration-type drive device not starting, and a desired rpm not being achieved.

Abstract: A vibration-type driving device comprises a vibration element including a driving member and an electro-mechanical energy conversion element having an electrode and arranged to displace the driving member with a driving signal supplied to the electrode, and a driven element that is kept in contact with the driving member of the vibration element. According to the driving signal supplied to the electrode of the electro-mechanical energy conversion element, the vibration element excites vibrations in two flexural vibration modes in which a direction of generation of a node in one mode is perpendicular to that in the other mode.

Abstract: A piezoelectric actuator A has an oscillator 10 that has a flat base layer 32 and piezoelectric elements 30, 31 layered on the base layer 32 and oscillates as a result of a drive signal applied to the piezoelectric elements 30, 31, and a rotor 100 driven by vibrations from the oscillator 10. The piezoelectric actuator A includes a fastening part 11 for securing the oscillator 10, and lead substrates 14A, 14B that are secured to the fastening part 11 for applying a drive signal to the piezoelectric elements from a drive circuit 500 for driving the piezoelectric elements 30, 31. The lead substrates 14A, 14B have connecting parts 17A–17C extending to the power supply electrodes 33A, 33C and a detection electrode 34.

Abstract: A rectangular vibrating plate 10 in which a piezoelectric element and a reinforcing plate are stacked is supported on a main plate by a support member 11, and is urged toward the rotor 100 by an elastic force of the support member 11. This brings a projection 36 provided on the vibrating plate 10 into abutment with an outer peripheral surface of the rotor 100. In this construction, when the vibrating plate 10 vibrates in the horizontal direction in the figure by an applied voltage from a driving circuit (not shown), the rotor 100 is rotated in a clockwise direction in accordance with the displacement of the projection 36 due to the vibration.

Abstract: A piezoelectric micromotor for moving a moveable element comprising: a vibrator in the shape of a rectangular parallelepiped formed from a plurality of thin layers of piezoelectric material having first and second identical relatively large rectangular face surfaces defined by long and short edge surfaces wherein the layers are aligned one on top of the other and have their face surfaces bonded together; electrodes on surfaces of the layers; a contact region located on one or more edge surfaces of the layers, urged against the body; and at least one electrical power supply that electrifies electrodes to excite vibrations in the vibrator and thereby in the contact region that impart motion to the body.

Abstract: An ultrasonic linear motor according to the present invention has a configuration wherein driving elements are glued at portions on faces of an ultrasonic transducer, facing one another, where rotational directions of elliptic vibrations generated on the faces are reverse one to another, a pair of guides are provided for being pressed into against the driving elements so as to hold the ultrasonic transducer therebetween, and leaf springs serving as pressing part are provided so as to narrow a spacing between the one pair of guides, whereby the ultrasonic transducer is configured as an self-moving ultrasonic linear motor which can drive by itself. Thus, driving properties of the ultrasonic transducer itself is improved, and also the size of the ultrasonic linear motor can be reduced.

Abstract: The present invention relates to a vibration wave driving apparatus includes a vibration element having an electro-mechanical energy conversion element that is disposed between a first elastic member and a second elastic member, characterized in that the vibration element can have a plurality of vibration modes which are different in relative displacement ration between respective ends of the vibration element. Specifically, a third elastic member is disposed between the first elastic member and the second elastic member, and the vibration element is allowed to have two portions which are different in dynamic stiffness from each other and are arranged in the axial direction thereof with the third elastic member interposed therebetween. According to this structure, the length of the vibration wave driving apparatus in the axial direction can be reduced and internal loss of vibration energy can be suppressed to be small.

Abstract: A stator includes first and second piezoelectric elements, a flexible aluminum-based connective arrangement and upper and lower aluminum-based metal blocks. The flexible aluminum-based connective arrangement includes first to fourth aluminum-based electrodes, which apply a voltage to the piezoelectric elements to generate a vibration. Each aluminum-based electrode is made of one of aluminum and an aluminum alloy and directly contacts a corresponding one of axial ends of the piezoelectric elements. Each aluminum-based metal block is made of one of aluminum and an aluminum alloy. The piezoelectric elements and the aluminum-based electrodes are interposed between the aluminum-based metal blocks.

Abstract: A vibration member for use in a vibration wave driving apparatus, and a vibration wave driving apparatus, the vibration member including an elastic member having a through hole, a fastening member having a threaded portion, an electro-mechanical energy transducer having a through hole, and a shaft inserted into the through holes of the elastic member and the electro-mechanical energy transducer, the shaft having a threaded screw portion that meshes with the threaded portion of the fastening member, and a step that restricts a position of the elastic member relative to the shaft in a thrust direction, wherein the elastic member is sandwiched between the step of the shaft and the fastening member and fixed therebetween by screwing and fastening the threaded screw portion of the shaft with the threaded portion of the fastening member, and the shaft is restricted from rotating relative to the elastic member.

Abstract: The invention relates to a piezoelectric drive, containing a driven element (1) fitted with a friction layer (2) and at least one solid-state plate-shaped piezoelectric transformer (6) as driving element. The length of the transform (L) does not match its width (H). First and second groups of electrodes (12, 13) are provided on the surfaces (7) of the transformer. The first and the second groups of electrodes have areas with identical configuration on the opposite large-surface metallized surfaces of the plate-shaped piezoelectric transformer. Each group of electrodes forms at least one independent transformer of the acoustic waves that are not coupled to one another and which propagate along the long side of the piezoelectric transformer. Hence, the first group of electrodes (12) operates as longitudinal wave generator (17) while the second group of electrodes (13) operates as flexural wave generator (18) of the acoustic waves.

Abstract: A vibration wave driving apparatus includes an electro-mechanical energy conversion element that is sandwiched and fixed between elastic members, in which a flange-shaped elastic member is provided between the electro-mechanical energy conversion element and one of the elastic members. When a driving vibration is applied to the electro-mechanical energy conversion element, bending vibrations are excited in a vibration element and those bending vibrations allow out-of-plane bending vibrations to be excited in the flange-shaped elastic member. A rotor is brought into contact with the third elastic member sandwiched between the elastic member and the electro-mechanical energy conversion element. A travelling wave produced by the bending vibration of the vibration element and a travelling wave produced by the out-of-plane bending vibration of the third elastic member are generated at the frictional surface of the vibration element.

Abstract: An elliptical vibratory cutting apparatus includes a control mechanism which applies a sinusoidal voltage having a predetermined phase difference to piezoelectric elements. Flexure vibrations are accordingly generated in X and Y directions. The vibrations in the X direction cause interference with the vibrations in the Y direction and vice versa. An amount of interference, caused by vibrations in one direction, with vibrations in another direction, is correctively eliminated by the control mechanism (interference eliminating unit. A workpiece is thus cut by means of a cutting tool through elliptical vibrations with high precision.

Abstract: Piezoelectric elements 10 and 10′ are driven so as to satisfy the relationship Nt=X0(1/(1/k2+1/k3)−1/(1/k1+1/k2+1/k3)) when the drive member, tip 20, and driven member, rotor 40, are in a state of intermittent contact, and in a state near the condition of transition from the intermittent contact state to the normal contact state. When the spring constant of the spring 41 is designated k1, the spring constant of the combined piezoelectric elements 10 and 10′ and the tip 20 is designated k2, the spring constant of the rotor 40 is designated k3, the amount of displacement of the piezoelectric elements 10 and 10′ is designated X0, and the compression force of the spring 41 is designated Nt.

Abstract: A single piezoelectric is excited at a first frequency to cause two vibration modes in a resonator producing a first elliptical motion in a first direction at a selected contacting portion of the resonator that is placed in frictional engagement with a driven element to move the driven element in a first direction. A second frequency excites the same piezoelectric to cause two vibration modes of the resonator producing a second elliptical motion in a second direction at the selected contacting portion to move the driven element in a second direction. The piezoelectric is preloaded in compression by the resonator. Walls of the resonator are stressed past their yield point to maintain the preload. Specially shaped ends on the piezoelectric help preloading. The piezoelectric can send or receive vibratory signals through the driven element to or from sensors to determine the position of the driven element relative to the piezoelectric element or resonator.

Abstract: An immunoassay, e.g. ELISA, method and kit for determining (preferably quantitatively) an analyte adsorbed at a surface or present in a liquid sample, comprising binding the analyte to a solid phase, attaching a marker to the analyte, and detecting marker attached to the solid-phase. The invention proposes to use a combination of marker and detection (e.g. an enzyme-substrate combination) which is capable of producing a precipitate on a solid phase which carries the marker and to detect the binding of analyte to the solid phase by in-situ determining the change in surface mass of the solid phase due to the formation of the precipitate. Ellipsometry is an example of a technique suitable for determining the change of surface mass of the solid phase, which could be made of a silicon- or chromium-sputtered glass slide The invention shortens the assay time and/or improves the assay sensitivity, and allows to measure extremely low surface concentrations of analytes of interest.

Abstract: The present invention is an actuator using a piezoelectric element as a displacement element, wherein a drive signal voltage and current are reduced, and power consumption is reduced, while output is increased. A structure comprising two displacement units of laminate-type piezoelectric elements 10 and 10′ and elastic elements 25 and 25′ resonated by the piezoelectric elements are arranged so as to mutually intersect, and a tip 20 provided at the intersection point of the elastic members 25 and 25′ describes a circular path or elliptical path, and moves a rotor 40. The oscillation of the piezoelectric elements 10 and 10′ is suppressed by the elastic members 25 and 25′, so as to set the phase of the electromotive force produced by the voltage effect of the piezoelectric elements 10 and 10′ themselves to the opposite of the phase of the drive signal, thereby reducing current consumption.

Abstract: An actuator using vibration caused by a piezoelectric element. The actuator includes: an driving rod bonded to one of the piezoelectric element; a engaging member for engaging frictionally with the driving rod; and a control circuit for applying the piezoelectric element with a driving voltage. The control circuit is provided with a drive circuit which generates a first set of the driving voltage for driving the engaging member, and with a friction reducing circuit which generates a second set of the driving voltage for reducing a frictional force exerting between the driving rod and the engaging member.

Abstract: A single piezoelectric is excited at a first frequency to cause two vibration modes in a resonator producing a first elliptical motion in a first direction at a selected contacting portion of the resonator that is placed in frictional engagement with a driven element to move the driven element in a first direction. A second frequency excites the same piezoelectric to cause two vibration modes of the resonator producing a second elliptical motion in a second direction at the selected contacting portion to move the driven element in a second direction. The piezoelectric is preloaded in compression by the resonator. Walls of the resonator are stressed past their yield point to maintain the preload. Specially shaped ends on the piezoelectric help preloading. The piezoelectric can send or receive vibratory signals through the driven element to or from sensors to determine the position of the driven element relative to the piezoelectric element or resonator.

Abstract: A vibration actuator includes a vibration element, which simultaneously generates a radial symmetric expansion vibration mode in which it expands and contracts in the radial direction and a non-axisymmetric planar vibration mode in which it bends to and fro in a non-axisymmetric manner within a single plane, and thereby drives a relative movement member, and a base member to which the vibration element is fixed. The vibration element includes at least one superimposed layer structure comprising a pair of electrical energy to mechanical energy conversion elements and an elastic member sandwiched between the pair of electrical energy to mechanical energy conversion elements. The elastic member includes a ring shaped portion to both the sides of which the pair of electrical energy to mechanical energy conversion elements are stuck, and a cylindrical shaped support portion, formed integrally with the ring shaped portion, which fixes the vibration element to the base member.

Abstract: A stacked electro-mechanical energy conversion element includes a plurality of layers made of a material having an electro-mechanical energy conversion function on which a plurality of electrode areas are formed, a first layer having an electro-conductive portion formed from the electrode area to a side face which is a non-stacked surface area, a second layer having a through-hole formed therein by an electro-conductive member, a third layer having an electro-conductive film which communicates the electro-conductive portion of the first layer and the through-hole of the second layer, and an external electro-conductive film formed on the side surface of the first layer so as to communicate with the electro-conductive portion.

Abstract: A truss type actuator including two piezoelectric devices drives a chip member provided at a crossing point of the piezoelectric devices for moving along an elliptic or a circular trail. Only one piezoelectric device is driven for transmitting vibrations thereof to the other non-driven piezoelectric device. By selecting a frequency of driving signals, both of the piezoelectric devices are resonantly vibrated with a phase difference of 90 degrees.

Abstract: The present invention provides a truss actuator offering reduced noise, vibration and wear, which is capable of speed control of the driven member and can control the output to the driven member at a constant level regardless of fluctuations in the load on the actuator or in the environment in which the actuator is used. In the truss actuator, one displacement unit 2 or 3 is driven and this oscillation is transmitted to the other displacement unit 3 or 2, and the truss actuator includes two displacement sensors 11 and 12 that respectively detect the displacement of the displacement units, a phase difference detecting unit 13 that detects via the displacement sensors the phase difference between the detected displacement values, a target phase difference setting unit (a CPU 20, etc.

Abstract: The present invention discloses an electromechanical actuator arrangement and a driving device for such an arrangement, having a plurality of drive element to be driven according to a wailing mechanism is provided. The driving device is characterised by an electrical power source (170) and at least two switches (172a, 172b) connected in series between the terminals (177) of the voltage source (170). An element terminal (178) is connected to a point (175) between said switches (172a, 172b), and a motor phase (174) of the actuator arrangement is connected to the element terminal (178). A control unit (171) is connected to control the switches (172a, 172b) in order to charge/discharge the drive elements. A charge control is thereby achieved by the use of the two switches (172a, 172b).

Abstract: An actuator includes at least two piezoelectric devices arranged for crossing displacing directions thereof at a predetermined angle, a chip member provided at a coupling point of the piezoelectric devices, and a spring for contacting the chip member to a rotor driven by the actuator. The piezoelectric device is driven for moving the chip member trailing an elliptical trail. The rotation velocity or the driving torque of the rotor is controlled by varying at least one of a length of a major axis or a minor axis of the elliptical trail and an inclination angle of the major axis or the minor axis with respect to a normal at a contacting point of the chip member and the rotor.

Abstract: A piezoelectric actuator has a base and a movable body disposed over a surface of the base for undergoing movement relative thereto. The movable body has a frame and at least one cantilever having a first end integrally connected to the frame and a second free end. A piezoelectric element is disposed on the cantilever for undergoing expansion and contraction movement in response to application of an alternating voltage to bring the second free end of the cantilever into and out of contact with the surface of the base to thereby move the movable body relative to the surface of the base. Spring members are connected to the frame of the movable body for regulating a direction of movement of the movable body relative to the surface of the base.

Abstract: An ultrasonic drive apparatus for preventing a slip between an object to be driven and a driving part of the apparatus to drive the object. The driving part includes an elastic member through which vibrations from electrical-mechanical converters are transmitted to the object. The elastic member can deform in a direction in which the object is driven. The driving part makes a predetermined locus to drive the object while the elastic member deforms in the direction so as to absorb the slip between the object and the driving part. The elastic member and the converters are mounted symmetrically relative to an axis which is generally perpendicular to the direction in which the object is driven, so that the object can be driven forward and backward.

Abstract: An ultrasonic motor has a vibrating body polarized in a given direction. The vibrating body comprises a first piezoelectric body and a second piezoelectric body laminated to the first piezoelectric body in a preselected direction generally parallel to the polarized direction. Each of the first piezoelectric body and the second piezoelectric body has a first polarized portion and a second polarized portion. The first polarized portion of the first piezoelectric body is aligned in the preselected direction with the second polarized portion of the second piezoelectric body. The second polarized portion of the first piezoelectric body is aligned in the preselected direction with the first polarized portion of the second piezoelectric body.

Abstract: In a truss-type driving apparatus, the amplitude of each displacement member and the phase difference therebetween are detected, and by adjusting the amplitudes or the phases of the impressed voltages to drive the displacement members based on the results of such detection, the elliptical locus drawn by the synthesizing member of the truss-type driving apparatus during driving is adjusted such that the desired driving characteristics are obtained.

Abstract: In a truss-type actuator, drive signals that have been subjected to frequency modulation are impressed to the electromechanical conversion elements in order to improve the driving of the actuator. By doing so, stable driving that is not affected by fluctuations in the resonance frequency is enabled without feedback.

Abstract: A multidirectional motor system for transmitting motion to a moveable element in at least two directions that are not collinear comprising a first motor that transmits motion to the moveable element along a direction determined by the orientation of the first motor and a second motor operable to change the orientation of said first motor.

Abstract: A single piezoelectric is excited at a first frequency to cause two vibration modes in a resonator producing a first elliptical motion in a first direction at a selected contacting portion of the resonator that is placed in frictional engagement with a driven element to move the driven element in a first direction. A second frequency excites the same piezoelectric to cause two vibration modes of the resonator producing a second elliptical motion in a second direction at the selected contacting portion to move the driven element in a second direction. The piezoelectric is preloaded in compression by the resonator. Walls of the resonator are stressed past their yield point to maintain the preload. Specially shaped ends on the piezoelectric help preloading. The piezoelectric can send or receive vibratory signals through the driven element to or from sensors to determine the position of the driven element relative to the piezoelectric element or resonator.

Abstract: A single piezoelectric is excited at a first frequency to cause two vibration modes in a resonator producing a first elliptical motion in a first direction at a selected contacting portion of the resonator that is placed in frictional engagement with a driven element to move the driven element in a first direction. A second frequency excites the same piezoelectric to cause two vibration modes of the resonator producing a second elliptical motion in a second direction at the selected contacting portion to move the driven element in a second direction. The piezoelectric is preloaded in compression by the resonator. Walls of the resonator are stressed past their yield point to maintain the preload. Specially shaped ends on the piezoelectric help preloading. The piezoelectric can send or receive vibratory signals through the driven element to or from sensors to determine the position of the driven element relative to the piezoelectric element or resonator.

Abstract: A driving apparatus that improves the precision of driving control for a driven member by reliably ensuring the desired motion of the tip member. Regulating members, which hold a piezoelectric actuator at positions opposite a rotor R, are located at positions separated from the piezoelectric actuator by a distance L that equals or exceeds the amplitude of the oscillation generated in the piezoelectric actuator.

Abstract: A single piezoelectric is excited at a first frequency to cause two vibration modes in a resonator producing a first elliptical motion in a first direction at a selected contacting portion of the resonator that is placed in frictional engagement with a driven element to move the driven element in a first direction. A second frequency excites the same piezoelectric to cause two vibration modes of the resonator producing a second elliptical motion in a second direction at the selected contacting portion to move the driven element in a second direction. The piezoelectric is preloaded in compression by the resonator. Walls of the resonator are stressed past their yield point to maintain the preload. Specially shaped ends on the piezoelectric help preloading. The piezoelectric can send or receive vibratory signals through the driven element to or from sensors to determine the position of the driven element relative to the piezoelectric element or resonator.

Abstract: There is provided an ultrasonic motor whose vibration loss is suppressed, whose structure is miniaturized, whose production process is simplified and which is capable of utilizing electrical energy very efficiently. The inventive ultrasonic motor comprises a first piezoelectric body having a first polarized portion excited when voltage is applied and a second piezoelectric body that is laminated with the first piezoelectric body in a body in the longitudinal direction parallel to the polarizing direction and having a first polarized portion at position separated from the first polarized portion of the first piezoelectric body in the transverse direction vertical to the polarizing direction and moves a moving body by vibration obtained by combining stretching vibration and bending vibration caused by distortion in the polarizing direction of the first polarized portion of the first piezoelectric body and the first polarized portion of the second piezoelectric body.

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: The present invention is an actuator using a piezoelectric element as a displacement element, wherein a drive signal voltage and current are reduced, and power consumption is reduced, while output is increased. A structure comprising two displacement units of laminate-type piezoelectric elements 10 and 10′ and elastic elements 25 and 25′ resonated by the piezoelectric elements are arranged so as to mutually intersect, and a tip 20 provided at the intersection point of the elastic members 25 and 25′ describes a circular path or elliptical path, and moves a rotor 40. The oscillation of the piezoelectric elements 10 and 10′ is suppressed by the elastic members 25 and 25′, so as to set the phase of the electromotive force produced by the voltage effect of the piezoelectric elements 10 and 10′ themselves to the opposite of the phase of the drive signal, thereby reducing current consumption.

Abstract: The invention relates to a motor having a cuboid piezoelectric element (1) which carries an actuating member (2) for transmitting a force in an actuating direction (x). In known motors the piezoelectric element (1) is restrained by four restraining elements which are disposed in the plane of vibration (x/y plane) and which exert a preloading force on the piezoelectric element (1) in a direction perpendicular to the actuating direction (x). However, this gives rise to a frictional force between the restraining elements and the piezoelectric element, which reduces the vibration quality and, as a consequence, the motor power. This is avoided by means of the invention, where the piezoelectric element (1) is restrained by means of restraining elements (20, 21, 22, 23) without preloading, i.e. with maximal slidability in the directions (y, z) perpendicular to the actuating direction (x).

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.