Abstract: An ultrasound transducer includes: a drive unit including a piezoelectric device; a proximal end block; and a distal end block. The distal end block includes a first portion, a supported portion, a second portion, and a third portion. The distal end block is configured such that a position of a boundary between the second portion and the third portion corresponds to or substantially corresponds to an antinode of the ultrasonic vibration while the piezoelectric device generates the ultrasonic vibration, and the ultrasonic vibration is being propagated to the proximal end block, the first portion, the second portion, and the third portion. A resonance frequency of the ultrasonic vibration differs according to a position of the boundary between the second portion and the third portion under a condition that a distance from the supported portion to a distal end of the third portion along the longitudinal axis is constant.

Abstract: A surgical instrument for use during a surgical procedure includes an instrument body, an ultrasonic transducer assembly extending along a longitudinal axis, a power cord, and a transducer slip joint. The ultrasonic transducer assembly is rotatably mounted within the instrument body about the longitudinal axis and defines a first outer profile. The power cord projects from the instrument body to provide electrical power to the ultrasonic transducer assembly for operating an acoustic waveguide. The transducer slip joint is positioned between the power cord and the ultrasonic transducer assembly and electrically and mechanically connects the power cord to the ultrasonic transducer assembly. The ultrasonic transducer assembly selectively rotates relative to the power cord for inhibiting the power cord from winding upon rotation of the ultrasonic transducer assembly. The transducer slip joint also defines a second outer profile that fits within the first outer profile of the ultrasonic transducer assembly.

Abstract: An ultrasonic motor is provided that includes a stator having a vibrator and first to fourth piezoelectric elements, a rotor, and a wiring member including an insulating substrate and first and second wirings. The piezoelectric elements are dispersedly arranged along the circumferential direction of a traveling wave circulating around an axial direction so that the traveling wave is generated by the vibrator being vibrated. The first and third piezoelectric elements face each other across the center of a traveling wave. The first wiring is electrically connected to the first and third piezoelectric elements, and the second wiring is electrically connected to the second and fourth piezoelectric elements. The second wiring passes over the third piezoelectric element from the second piezoelectric element side and extends toward the side of fourth piezoelectric element.

Abstract: A vibration actuator includes an electro-mechanical transducer, a vibrating body fixed to the electro-mechanical transducer, the vibrating body being vibrated by applying a voltage to the electro-mechanical transducer, and a driven body contacting the vibrating body. The driven body is frictionally driven by a vibration of the vibrating body. The driven body includes a first extended portion extending from a main body portion of the driven body towards an inside diameter side of the vibrating body, a second extended portion extending from the first extended portion towards the outside diameter side of the vibrating body, and a contact surface provided at a tip of the second extended portion. The contact surface contacts the vibrating body. The first extended portion, the second extended portion, and the contact surface are each capable of elastically deforming in a rotational axis direction of the driven body.

Abstract: The vibration-type-motor driving apparatus includes a vibration-type motor including a vibrator on which vibration is excited by an electro-mechanical energy conversion element, a shaft that supports the vibrator, and a rotor that contacts the vibrator to be rotated thereby. A first end portion of the shaft is moved with the vibration of the vibrator. The apparatus further includes a housing that houses therein the motor, and a first elastic member that contacts the first end portion of the shaft and is deformable in a direction in which the first end portion vibrates. The first elastic member transfers heat of the shaft to the housing or another member provided inside the housing.

Abstract: A vibrator including an electro-mechanical transducer and an elastic body that is fixed to the electro-mechanical transducer and that is provided with a projection, the projection having a hollow structure. The projection includes a contact portion having a first surface at a tip, the first surface being parallel to a first plane, a wall portion projecting towards an opposite side with respect to the electro-mechanical transducer, and a connection portion connecting the wall portion and the contact portion to each other. The connection portion having a spring property, and the contact portion includes a portion of which a cross-sectional area in a second plane that is parallel to the first plane increases as an increase of a distance between the portion and the first surface.

Abstract: Apparatus, and a corresponding method for its operation, for precisely moving a movable rotor by urging a motor, such as a piezoelectric motor, into operative engagement with a circumferential rim-like portion of the rotor, with a radial preload force great enough to produce tangential motion in the rim-like portion and thereby to move the rotor in any desired manner and with very high precision. Possible damaging effects of the radial preload force are canceled by the introduction of an oppositely directed radial resistive force, such as by means of one or more pinch rollers positioned opposite the motor and also engaging the rim-like member. The motor is mounted in an assembly that permits limited sliding and pivoting movements of the motor and thereby allows the motor to adapt to any physical irregularities in the driven rim-like member.

Abstract: A highly-durable vibratory drive apparatus is provided without the need for additional assembly processes. The vibratory drive apparatus includes: a vibrator including a first elastic member, a second elastic member and an electro-mechanical energy conversion element, the electro-mechanical energy conversion element being between the first elastic member and the second elastic member; a moving member configured to contact the vibrator and be moved relative to the vibrator; and a lubricant provided between the first elastic member and the electro-mechanical energy conversion element.

Abstract: A haptic actuator apparatus and a method of making the same include an ultrasonically vibrating motor and its housing. The housing includes a guide structure coupled to the ultrasonically vibrating motor and at least one spring. The guide structure defines at least one path of motion of the ultrasonically vibrating motor. The at least one spring delimits the at least one path and generates human-detectable vibrations in response to an impact with the ultrasonically vibrating motor.

Abstract: In one general aspect, various embodiments are directed to an ultrasonic surgical instrument that comprises a transducer configured to produce vibrations along a longitudinal axis at a predetermined frequency. In various embodiments, an ultrasonic blade extends along the longitudinal axis and is coupled to the transducer. In various embodiments, the ultrasonic blade includes a body having a proximal end and a distal end, wherein the distal end is movable relative to the longitudinal axis by the vibrations produced by the transducer.

Abstract: A vibration wave driving apparatus including: a vibrator in which a first elastic body, a second elastic body and an electrical-mechanical energy converting element provided between the first and the second elastic bodies are arranged in a direction of a rotation axis; a rotor performing a rotational motion due to the vibration excited to the first elastic body by applying a driving signal to the electrical-mechanical energy converting element; an output transmitter rotating synchronously with the rotor; and a shaft passing through the vibrator, the rotor and the output transmitter in the direction of the rotation axis, wherein the output transmitter has a fitting portion to which the shaft or a flange fixed to the shaft is fitted, and wherein a portion of the fitting portion of the output transmitter and a portion of the first elastic body are overlapped in a direction perpendicular to the rotation axis.

Abstract: Provided is a piezoelectric element including: an electrode portion including a piezoelectric layer and an electrode layer that are laminated; and a non-electrode portion that is in contact with the electrode portion and includes a piezoelectric layer without an electrode layer, in which the non-electrode portion includes a region having a density smaller than a density of the piezoelectric layer of the electrode portion.

Abstract: An ultrasonic motor includes a stator. The stator includes a seat and a driving unit. The driving unit includes a generally semi-elliptical driving mechanism formed integrally with the seat, and two spaced-apart piezoelectric actuators disposed between the seat and the driving mechanism. Each of the piezoelectric actuators has a first end abutting against the driving mechanism, and a second end opposite to the first end and abutting against the seat.

Abstract: In an ultrasonic motor, an elliptical vibration is generated by combining a longitudinal primary resonance vibration, resulting from an expansion and a contraction of a vibrator in a direction of a central axis, and a torsional secondary resonance vibration or a torsional tertiary resonance vibration resulting from twisting of the vibrator about the central axis. A dimension ratio of a rectangle of the vibrator is chosen such that a resonance frequency of the longitudinal primary resonance vibration, resulting from the expansion and the contraction of the vibrator in the direction of the central axis, and a resonance frequency of the torsional secondary resonance vibration or the torsional tertiary resonance vibration, resulting from twisting of the vibrator about rotation axis, substantially match.

Abstract: In an ultrasonic actuator, piezoelectric layers and internal electrode layers are stacked. External electrodes are formed on a principal surface exposed to an outside of the outermost piezoelectric layer. Side electrodes connected to the internal electrode layers and the external electrodes are formed on side surfaces of a body including the piezoelectric layers and the internal electrode layers. A first divided electrode and a first external electrode are connected together by a plurality of side electrodes. A second divided electrode and a second external electrode are connected together by a plurality of side electrodes. A minus electrode layer and a third external electrode are connected together by a plurality of side electrodes.

Abstract: A vibration type driving apparatus is provided, in which a plurality of vibration members include rotation units that are formed so as to be rotatable around respective rotation axes that are parallel to respective directions of forces generated by elliptical movements; in which any vibration member that is positioned in a range where an angle between a direction of movement of a moving member and the corresponding rotation axis is greater than a predetermined angle is tilted by the rotation unit, and vibration mode for push-up moving is generated at the any vibration member; and in which the elliptical movement of any vibration member that is positioned in a range where the angle is less than the predetermined angle causes the moving member to move.

Abstract: In one general aspect, various embodiments are directed to an ultrasonic surgical instrument that comprises a transducer configured to produce vibrations along a longitudinal axis at a predetermined frequency. In various embodiments, an ultrasonic blade extends along the longitudinal axis and is coupled to the transducer. In various embodiments, the ultrasonic blade includes a body having a proximal end and a distal end, wherein the distal end is movable relative to the longitudinal axis by the vibrations produced by the transducer.

Abstract: An elliptical vibration is generated by combining a longitudinal primary resonance vibration of the vibrator resulting from an expansion and a contraction of the vibrator in a direction of the central axis and a torsional resonance vibration resulting from twisting of the vibrator around the central axis as a torsional axis. The dimension ratio of the rectangle of the vibrator is chosen such that a resonance frequency of the longitudinal primary resonance vibration resulting from the expansion and the contraction of the vibrator in the direction of the central axis and a resonance frequency of the torsional resonance vibrations resulting from twisting of the vibrator around the central axis as the torsional axis match. The ultrasonic motor further includes a vibration detecting electrode layer.

Abstract: A Langevin transducer horn uses split electroding or selective electroding of transducer elements and phase relationships of the voltages applied thereto to determine the relative longitudinal and flexural/transverse motion induced in the tip of the horn.

Abstract: In an ultrasonic motor, an elliptical vibration is generated by combining a longitudinal primary resonance vibration resulting from an expansion and a contraction of a vibrator in a direction of a central axis and a torsional secondary resonance vibration or a torsional tertiary resonance vibration resulting from twisting of a rotation axis. A dimension ratio of a rectangle of the vibrator is chosen such that a resonance frequency of the longitudinal primary resonance vibration and a resonance frequency of the torsional secondary resonance vibration or the torsional tertiary resonance vibration match. The vibrator includes a plurality of regions in a surface orthogonal to the central axis, and deformations of the regions adjacent to each other along the direction of the central axis are mutually different. The vibrator expands and contracts in a direction along a polarization direction thereof.

Abstract: In an ultrasonic motor, an elliptical vibration is generated by combining a longitudinal primary resonance vibration resulting from an expansion and a contraction of the vibrator in a direction of the central axis and a torsional secondary resonance vibration or a torsional tertiary resonance vibration resulting from twisting of a rotation axis, and the dimension ratio of the rectangle of the vibrator is chosen such that a resonance frequency of the longitudinal primary resonance vibration, resulting from the expansion and the contraction of the vibrator in the direction of the central axis and a resonance frequency of the torsional secondary resonance vibration or the torsional tertiary resonance vibration resulting from twisting of the rotation axis match. The vibrator includes a torsional piezoelectric body that generates a thickness shear vibration, and that is arranged at an anti-node position of the torsional secondary resonance vibration or the torsional tertiary resonance vibration.

Abstract: In an ultrasonic motor, an elliptical vibration is generated by combining a longitudinal primary resonance vibration resulting from an expansion and a contraction of a vibrator in a direction of a central axis and a torsional secondary resonance vibration or a torsional tertiary resonance vibration resulting from twisting around the central axis. A dimension ratio of a rectangle of the vibrator is chosen such that a resonance frequency of the longitudinal primary resonance vibration and a resonance frequency of the torsional secondary resonance vibration or the torsional tertiary resonance vibration match. The vibrator includes a plurality of regions in a surface orthogonal to the central axis, and deformations of the regions adjacent to each other along the direction of the central axis are mutually different. The vibrator expands and contracts in a direction orthogonal to a polarization direction thereof.

Abstract: An ultrasonic vibration apparatus includes a vibrator, wherein the vibrator includes at least two vibration elements to generate ultrasonic vibration when a driving voltage is applied to the vibration elements, at least three electrode portions wherein the vibration elements and the electrode portions is alternately arranged side by side in a vibrating direction, at least the three electrode portions includes at least two first electrode portions and at least one second electrode portion alternately arranged in the vibrating direction, the vibrator integrally vibrates ultrasonically in the vibrating direction when the driving voltage is applied to the first electrode portions and the second electrode portion, and a bridging portion coupling and electrically connecting two first electrode portions of at least the two first electrode portions with each other, and the ultrasonic vibration apparatus further includes an anti-vibration portion to suppress vibration of the bridging portion in any other direction exc

Abstract: In an ultrasonic motor, an elliptical vibration is generated by combining a longitudinal primary resonance vibration resulting from an expansion and a contraction of the vibrator in a direction of the central axis and a torsional secondary resonance vibration or a torsional tertiary resonance vibration resulting from twisting of a rotation axis, and the dimension ratio of the rectangle of the vibrator is chosen such that a resonance frequency of the longitudinal primary resonance vibration, resulting from the expansion and the contraction of the vibrator in the direction of the central axis and a resonance frequency of the torsional secondary resonance vibration or the torsional tertiary resonance vibration resulting from twisting of the rotation axis match. The vibrator includes a torsional piezoelectric body that generates a thickness shear vibration, and that is arranged at an anti-node position of the torsional secondary resonance vibration or the torsional tertiary resonance vibration.

Abstract: The present invention relates to a piezoelectric linear motor that can make relatively low abrasion and accurate linear movement since stationary AC voltages are applied to two piezoelectric elements with a phase difference. The present invention provides a piezoelectric linear motor, comprising: a piezoelectric substrate having a first piezoelectric element and a second piezoelectric element, wherein AC voltages are applied to the first and second piezoelectric elements with a phase difference; a metallic elastic body having first and second elastic bodies coupled to the piezoelectric elements and a central protrusion protruded at the central portion connecting the first and second elastic bodies, wherein the central protrusion oscillates elliptically during an application of the voltage; and a mover brought into contact with the central protrusion of the metallic elastic body for a linear movement, and wherein the movement of the mover is orthogonal to the central protrusion.

Abstract: A piezo drive system includes an elastic fixing frame, a drive element, a rod, and a rotor. A vamplate portion is formed on the outer surface of the rod. One end of the rod is secured to around the center of a face of the drive element. The rotor consists of a cylindrical portion and a disk portion, and can rotate relative to the rod. Protrusions are formed on the inside of a top surface portion of the fixing frame to push against the disk portion. Using the drive element, the rod rotates while tilting and makes a surface contact with the vamplate portion, producing friction. Consequently, the rotor is rotated.

Abstract: An ultrasonic transducer includes: piezoelectric elements; a pair of clamping members which clamp said piezoelectric elements; and a cover member which is crimped to at least one of said pair of clamping members in a state where said cover member cooperates with said pair of clamping members to surround said piezoelectric elements.

Abstract: A vibration wave driven apparatus includes a vibrator configured to generate vibration, a rotor configured to be in frictional contact with the vibrator and to rotate about an axis of rotation, and a transmitting member configured to rotate about the axis and to transmit rotation of the rotor to an external component. A part of the transmitting member forms a worm portion of a worm gear.

Abstract: To provide a screw fastening device that, when performing a screw tightening operation, can substantially reduce the running torque directly applied by external force 5 to a screw driving device.

Abstract: Provided is a vibration actuator in which a plurality of rotors can be driven by a single vibration unit. Two rotors (A) and (B) are attracted toward corresponding stators to be contacted with and pressurized against the corresponding stators (3) and (4), respectively, through a tension of a wire member (8). A composite vibration combining a plurality of vibrations is generated by a composite vibrator (2) to cause elliptical movements in corner portions of the stators (3) and (4). As a result, the two rotors (A) and (B) abutting onto and pressurized against the two stators (3) and (4) are rotated about rotation centers (C1) and (C2) thereof, respectively, at the same time.

Abstract: Provided is a stacked type piezoelectric element including a surface electrode layer as a first layer and a piezoelectric layer as a second layer. A third layer to an N-th layer thereof are formed by alternately arranging piezoelectric layers and piezoelectric layers. A surface of the piezoelectric layer is provided with four-way split inner electrodes S+, B+, A?, and B?. A surface of the piezoelectric layer is provided with four-way split inner electrodes AG+, BG+, AG?, and BG?. A surface of the piezoelectric layer is provided with four-way split inner electrodes of A+, B+, A?, and B?. The piezoelectric layers are formed such that only the inner electrode S+ serving as a sensor phase and the inner electrodes A+ and AG+ being arranged in the same phase as the inner electrode S+ are exposed to an outside of the piezoelectric layer.

Abstract: The present invention relates to an ultrasonic motor comprising a stator formed by using an acoustic waveguide of helical coil shape or an acoustic waveguide of in-plane spiral coil shape, so that a rotor placed in close proximity to, or in close contact with the coil is rotated, traveled, or performed curved line movement by the propagation of the wave on the stator, thereby eliminating the provision of a preload spring and an absorber, simplifying the structure of the motor, reducing the size of the motor, and enabling to work in a liquid environment without water proofing and rotation of a hollow tube.

Abstract: A stacked piezoelectric element comprising that can suppress periodic damping on miniaturization of a vibration wave motor and improve its performance. A stacked piezoelectric element comprises piezoelectric layers and electrode layers alternately stacked to have a shape of a cylinder. The electrode layers are divided into a plurality of electrode layer regions along a circumferential surface of the shape of a cylinder.

Abstract: A driving device includes a drive source, a driving unit, and a driven member. The drive source is configured and arranged to generate a driving force. The driving unit is coupled to the drive source to move with a reciprocating motion between first and second directions by the driving force. The driven member is arranged to frictionally engage with the driving unit to move in the first direction in response to the reciprocating motion of the driving unit. The driving unit is further arranged to convert a portion of the driving force into a pressing force that acts on the driven member in a direction substantially perpendicular to the first and second directions with a first conversion ratio when the driving unit moves in the first direction and with a second conversion ratio smaller than the first conversion ratio when the driving unit moves in the second direction.

Abstract: A vibrational actuator includes an oscillator that generates vibrational energy; a mover that is rotationally driven around a first axis by the vibrational energy; an output shaft that rotates around a second axis by using a rotational force communicated from the mover; and a flange portion projecting out from the output shaft along a direction intersecting the second axis, that rotates together with the output shaft. Pressure is applied to the mover at a position between the flange portion and the oscillator. A distance from the first axis to an outer portion of the mover over an area where the mover is pressed against the flange portion is set to a value large enough to prevent the first axis and the second axis from becoming tilted relative to each other.

Abstract: The invention is intended to provide a high-capacity ultrasonic composite oscillating device that is sufficiently rigid as a composite oscillating body for various strong ultrasonic applications. One constructed such that BLTs (1, 1?, 2, 2?, . . . n, n?) of the same characteristics are disposed around an outer peripheral portion of a disk-shaped oscillating body 4 in n-sets opposed to each other and disposed at regular intervals, opposed BLTs being driven in an opposite phase mode, and driven in an oscillating mode in which the phase between the BLTs in adjacent sets is shifted by ?/n, and an oscillating rod connected to a center of the disk-shaped oscillating body is induced with a composite oscillation output of oscillation capacity n-times that of one set of BLTs induced in the center of the disk-shaped oscillating body 4, and one in which a plurality of these oscillating devices are jointed together to increase the oscillation capacity.

Abstract: Ultrasonic devices having transducer assembly including a stack of alternating electrodes and piezoelectric elements. A mounting device having a first and second end is adapted to receive ultrasonic vibration from the stack and transmit it from the first to the second end. A bolt including a head and shaft is configured to threadedly engaged the mounting device. The transducer assembly includes a deformable pressure element having a central opening that permits insertion of the shaft therethrough, and has a convex side facing the bolt head and a concave side facing the stack in a non-deformed state, but, in a deformed state, applies compression forces to the stack based on the deformation. The deformable pressure element may alternately include a surface area, in its deformed state, substantially equivalent to the surface area of a piezoelectric element and/or a first and second beveled surface defining the concave side.

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 vibration-wave drive motor incorporating a multilayer piezoelectric element having reduced vibration damping as well as a design lending itself to reduced manufacturing costs and miniaturization. The multilayer piezoelectric element includes a piezoelectric active part formed by a plurality of piezoelectric layers having an internal electrode, and a piezoelectric inactive part formed by an integrated piezoelectric layer with no internal electrodes. The vibration-wave drive motor consists of a vibration body including the multilayer piezoelectric element, and a contact body press contacting the vibration body.

Abstract: A vibration element for a vibration wave driving apparatus includes a first elastic member, a second elastic member, and an electro-mechanical energy conversion element disposed between the first and second elastic members. The electro-mechanical energy conversion element generates in the vibration element at least one of a plurality of vibration modes. Each vibration mode is generated in accordance with a frequency of a driving signal applied to the electro-mechanical energy conversion element and has the same direction of displacement, but has a different relative ratio between displacements of respective ends of the vibration element.

Abstract: A method for accelerating or decelerating a moveable body which body is moved by urging a piezoelectric micromotor to the body in a first direction so that a contact region of the piezoelectric motor is pressed to the body and exciting vibrations in the piezoelectric micromotor at the contact region in the first direction and in a second direction along a direction of motion of the body, said vibrations having a first amplitude in the first direction and a second amplitude in the second direction, the method comprising: a) for acceleration, gradually changing a ratio between the second amplitude relative to the first amplitude from substantially zero to a desired non-zero value; or b) for deceleration, gradually changing the ratio between the second amplitude relative to the first amplitude from a non-zero value to substantially zero.

Abstract: A rotary drive device is configured to be reduced in size while still delivering a prescribed torque. The rotary drive device has a base part with a vibrating body and a rotating body attached to the base part. The vibrating body has at least one piezoelectric element that vibrates an abutting part, which rotates the rotating body. Specifically, the rotating body has a contact part that is positioned at a prescribed distance from the rotational center and that is abutted against by the abutting part. When voltage is applied to the piezoelectric element, the vibrating body vibrates to repetitively press the abutting part against the contact part to rotate the rotating body. The vibrating body is positioned in a plane that intersects the rotational axis of the rotating body, and is disposed at least as close to the rotational axis of the rotating body as that of the contact part.

Abstract: An ultrasonic transducer in which internal electrodes and piezoelectric elements are alternately layered includes outer electrodes, each being connected to the corresponding internal electrodes. The ultrasonic transducer has a first layered part, a second layered part, a first outer-electrode group, and a second outer-electrode group. The first layered part includes at least the internal electrodes, each being divided in half in a second direction orthogonal to a layering direction, which is a first direction. The second layered part includes at least the internal electrodes, each being divided in half in a third direction orthogonal to the first direction and the second direction. The first outer-electrode group is provided so as to be connected to predetermined internal electrodes in the first layered part. The second outer-electrode group is provided so as to be connected to predetermined internal electrodes in the second layered part.

Abstract: An acoustic driver assembly for use with a spherical cavitation chamber is provided. The acoustic driver assembly includes at least one transducer, a head mass and a tail mass, coupled together with a centrally located threaded means (e.g., all thread, bolt, etc.). The driver assembly is either attached to the exterior surface of the spherical cavitation chamber with the same threaded means, a different threaded means, or a more permanent coupling means such as brazing, diffusion bonding or epoxy. In at least one embodiment, the transducer is comprised of a pair of piezo-electric transducers, preferably with the adjacent surfaces of the piezo-electric transducers having the same polarity. The surface of the head mass that is adjacent to the external surface of the chamber has a spherical curvature greater than the spherical curvature of the external surface of the chamber, thus providing a ring of contact between the acoustic driver and the cavitation chamber.

Abstract: An acoustic driver assembly for use with a spherical cavitation chamber is provided. The acoustic driver assembly includes at least one transducer, a head mass and a tail mass, coupled together with a centrally located threaded means (e.g., all thread, bolt, etc.). The head mass of the driver assembly is permanently attached to the exterior surface of the spherical cavitation chamber via brazing or diffusion bonding. In at least one embodiment, the transducer is comprised of a pair of piezo-electric transducers, preferably with the adjacent surfaces of the piezo-electric transducers having the same polarity. The surface of the head mass that is adjacent to the external surface of the chamber has a spherical curvature equivalent to the spherical curvature of the external surface of the chamber, thus providing maximum coupling efficiency between the acoustic driver and the cavitation chamber.

Abstract: An ultrasonic motor comprises a piezoelectric vibrating member having a detecting polarized portion for detecting a drive signal having a drive frequency of the detecting polarized portion and a driving polarized portion for receiving the drive signal to oscillate the piezoelectric vibrating member in self-excited oscillation to produce a drive force. The detecting polarized portion is disposed at a portion of the piezoelectric vibrating member for undergoing maximum deformation in at least one vibration mode of oscillation of the piezoelectric vibrating member. An amplifying circuit amplifies the drive signal detected by the detecting polarized portion and inputs the amplified signal to the driving polarized portion to oscillate the piezoelectric vibrating member.

Abstract: An ultrasonic transducer having an ultrasonic conducting element with a plurality of arms extending from a common junction with some of the arms being provided with ultrasonic generators, at least one other arm carrying a bonding tool, especially for bonding a conductor to a chip and at least two of the arms including a straight angle of 180° with one another.

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: The present invention relates to a linear motor which draws its operating power from ultrasonic vibration above the frequency of 20 kHz which is generated by piezoelectric ceramic. More particularly, the invention relates to a linear piezoelectric ultrasonic motor which linearly operates a slider due to a frictional force generated by applying sinusoidal electric field with a 90 degree phase difference to a pair of piezoelectric ceramic. This causes an elliptical mechanical vibration on a shaking beam which is connected to the piezoelectric ceramic.

Abstract: An acoustic driver assembly for use with a spherical cavitation chamber is provided. The acoustic driver assembly includes at least one transducer, a head mass and a tail mass, coupled together with a centrally located threaded means (e.g., all thread, bolt, etc.). The driver assembly is permanently attached to the exterior surface of the spherical cavitation chamber via brazing or diffusion bonding. In at least one embodiment, the transducer is comprised of a pair of piezo-electric transducers, preferably with the adjacent surfaces of the piezo-electric transducers having the same polarity. The surface of the head mass that is adjacent to the external surface of the chamber has a spherical curvature equivalent to the spherical curvature of the external surface of the chamber, thus providing maximum coupling efficiency between the acoustic driver and the cavitation chamber. In at least one embodiment a void filling material is interposed between one or more pairs of adjacent surfaces of the driver assembly.