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: An ultrasonic motor is provided with a circular stator including a piezoelectric element and a comb teeth body with a multitude of comb teeth circumferentially aligned thereon, and a circular rotor supported by a rotating shaft and pressed against the comb teeth body, wherein the comb teeth respectively include, at least in a portion thereof press-contacting the rotor, a plurality of pin-shaped elements radially aligned at a predetermined interval. The pin-shaped element is elastically deformable in a radial direction at least in a tip portion thereof, and has a predetermined rigidity in a circumferential direction.

Abstract: An ultrasonic motor is provided with a circular stator including a piezoelectric element and a comb teeth body and a circular rotor supported by a rotating shaft and disposed in close contact with the comb teeth body. The stator and the rotor are magnetized in opposite polarities to each other so that the stator and the rotor are brought into close contact by an attractive magnetic force generated therebetween in an axial direction.

Abstract: The present invention provides an ultrasonic motor including a wire having a coiled stator at one end thereof, a vibration generating device disposed at another end of the wire, a moving member that is in contact with the stator, a guide member that guides the rotation of the moving member, and an elastic member that covers the periphery of the wire. Accordingly, the driving efficiency of the ultrasonic motor that has a simple structure and that can be easily downsized can be enhanced and the performance stability thereof can be realized.

Abstract: An electromechanical motor (1), using at least two bimorph, monomorph or multimorph electromechanical actuating elements (6) interconnected by a common actuator backbone (5) is disclosed. The actuating elements (6) are controllable in both a longitudinal direction (L), i.e. in the main extension direction of the actuating element (6), and a flexural direction, i.e. bending of the actuating element (6), separately. The different actuating elements (6) can be controlled individually as well. The actuator (3) dimensions are preferably selected to resonance frequencies in vicinity of a certain frequency. The actuating elements (6) are provided with interaction portions (7) at which any contact between the actuator and a body (2) to be moved is made. In order to operate well both in fine-positioning and resonant motion, the interaction portions (7) are arranged to partially suppress the transfer of acoustic waves between the actuating elements (6) and the body (2) to be moved.

Abstract: The present invention relates to a ceramic tube type ultrasonic motor having a stator including a tube-type elastic body that is formed of a ceramic material; and a plurality of piezoelectric diaphragms that are attached on the outer peripheral surface of the elastic body in a longitudinal direction thereof and to which voltages having a phase difference are respectively applied and a rotor that is rotated by the friction with the elastic body flexurally vibrating due to the voltages applied to the plurality of piezoelectric diaphragms.

Abstract: A rotary ultrasonic piezoelectric motor is provided and a method of exciting a flexure traveling wave to drive the motor. The motor includes a stator having a piezoelectric ceramic disc polarized in the radial direction and bounded by a top electrode and a segmented bottom electrode. The motor also includes a power source for applying two pairs of alternating voltages to the bottom electrode segments to excite a shear-shear mode vibration in the stator, resulting in a shear-shear mode flexure traveling wave in the stator. The motor further includes a rotor operatively connected to the stator, and the stator is driven to rotate through a frictional force between the rotor and the stator due to the traveling wave deformation of the stator. A linear ultrasonic piezoelectric motor and method of exciting a flexure traveling wave to linearly drive the motor is provided. The motor includes a stator having a rectangular piezoelectric ceramic plate that is polarized in the longitudinal direction.

Abstract: A piezoelectric/electrostrictive device has a rotor substantially in the form of a rectangular parallelepiped, and a rotary actuator for angularly displacing the rotor 12. The rotary actuator includes a stationary member, a first vibratory plate and a second vibratory plate extending in one direction from opposite sides of the stationary member, a first piezoelectric/electrostrictive element for actuating the first vibratory plate, and a second piezoelectric/electrostrictive element for actuating the second vibratory plate. The rotor includes a pair of opposite surfaces, one of the surfaces having a first end secured to an end of the first vibratory plate and a second end, which is diagonally opposite to the first end, and which is secured to an end of the second vibratory plate.

Abstract: A micro-beam friction liner adapted to increase performance and efficiency and reduce wear in a piezoelectric motor or actuator or other device using a traveling or standing wave to transfer energy in the form of torque and momentum. The micro-beam friction liner comprises a dense array of micro-beam projections having first ends fixed relative to a rotor and second ends projecting substantially toward a plurality of teeth of a stator, wherein the micro-beam projections are compressed and bent during piezoelectric movement of the stator teeth, thereby storing the energy, and then react against the stator teeth to convert the stored energy stored to rotational energy in the rotor.

Abstract: A vibration wave driving apparatus includes a vibration member in which an electro-mechanical energy conversion element is fixed to an elastic member, and a contact member pressed against a sliding part provided in the vibration member, so as to be kept in contact therewith. The vibration wave driving apparatus is configured to supply alternating signals in a predetermined driving frequency band to the electro-mechanical energy conversion element, thereby generating a predetermined natural vibration mode in the elastic member to drive the contact member. In the apparatus, the natural vibration mode is generated in the elastic member, a natural frequency of another vibration mode different from the natural vibration mode is detected, and a stiffness of the support member is altered if the natural frequency of the other vibration mode detected is included in the driving frequency band.

Abstract: The vibration wave linear motor of the present invention is structured comprising a driven component, a first vibrator having two or more driving contacting parts for driving the driven component in a certain predetermined direction, a second vibrator having one or more driving contacting parts for driving the driven component in the same direction as the drive by the first vibrator, a first supporting part for fixing and holding either one of the first or second vibrators, a second supporting part for holding the other of either the first or second vibrator such that swinging is possible, and a pressing component for pressing the first or second vibrator which is held by the second supporting part, such as to enable swinging, to the driven component.

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: 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 rotary ultrasonic piezoelectric motor is provided and a method of exciting a flexure traveling wave to drive the motor. The motor includes a stator having a piezoelectric ceramic disc polarized in the radial direction and bounded by a top electrode and a segmented bottom electrode. The motor also includes a power source for applying two pairs of alternating voltages to the bottom electrode segments to excite a shear-shear mode vibration in the stator, resulting in a shear-shear mode flexure traveling wave in the stator. The motor further includes a rotor operatively connected to the stator, and the stator is driven to rotate through a frictional force between the rotor and the stator due to the traveling wave deformation of the stator. A linear ultrasonic piezoelectric motor and method of exciting a flexure traveling wave to linearly drive the motor is provided. The motor includes a stator having a rectangular piezoelectric ceramic plate that is polarized in the longitudinal direction.

Abstract: An electromechanical actuator 10 is disclosed, having drive elements (14a–d) movable in two dimensions and connected to an actuator backing (12). The actuator backing (12) is made of a material being ferromechanically inactive. Furthermore, the joint between the drive element (14a–d) and the actuator backing (12) is stiff and highly stable. This is achieved by use of an irreversible joint made e.g. by thermoset plastic glues, diffusion bonding or co-sintering. Co-sintering is to prefer. The actuator backing (12) material is selected to be stiff, preferably having a stiffness above 70 GPa and more preferably above 100 GPa, and having a high heat conductivity, preferably above 5 W/mK and more preferably above 10 W/mK, Electrodes (22) are preferably integrated in the actuator backing to increase stiffness as well as improving the heat conductivity. The drive elements (14a–d) are preferably covered (28, 26), at least at the driving surface, by heat-conducting material.

Abstract: A vibration type driving apparatus, which is capable of increase of output torque and rotational speed without increasing the size of a vibration body, is described. The apparatus comprises a vibration body which generates vibration by supplying a driving signal to an electro-mechanical energy converting element and a contact body which contacts this vibration body and is moved by vibration received from the vibration body. The vibration body comprises a base portion having the electro-mechanical energy converting element and a plurality of vibration amplification portions for amplifying vibration generated at this base portion. Neighboring vibration amplification portions of the plurality of vibration amplification portions are connected at a position different from a connecting position of each vibration amplification portion with the base portion.

Abstract: A piezoelectric motor has a vibrating body for undergoing vibrational movement in accordance with a vibration wave, a contact member disposed in contact with and driven by the vibrating body during vibration thereof, and a support member for supporting the vibrating body in the vicinity of a vibration node of the vibration wave. A pressurization member applies pressure to the support member along a pressurization axis to maintain the vibrating body in pressure contact with the contact member so that during vibration of the vibrating body, the support member regulates movement of the vibrating body in a direction of rotation about the pressurization axis.

Abstract: The present invention relates to a vibration wave driving apparatus including: a vibration member which has an electro-mechanical energy conversion element having a plurality of electrode regions that are fixed to an elastic member and polarized in the same direction, and which generates a travelling wave that is obtained by synthesizing a plurality of standing waves different in phase on a surface of the elastic member by supplying an ac signal to the electro-mechanical energy conversion element; and a moving member which is in contact with the vibration member and driven by the travelling wave.

Abstract: An ultrasonic motor has a piezoelectric vibrator driven by a voltage signal to undergo expansion and compression movement. At least two elastic bodies are connected to opposite ends of the piezoelectric vibrator and are vibrationally driven by the expansion and compression movement of the piezoelectric vibrator. Each of the elastic bodies has at least one groove formed in a surface thereof for converting the expansion and compression movement of the piezoelectric vibrator into torsional vibration so that the elastic bodies generate a combination of longitudinal vibration and torsional vibration. A movable member is connected to the elastic bodies to be frictionally driven by the combination of longitudinal and torsional vibrations generated by the elastic bodies.

Abstract: The present invention concerns a piezoelectric motor of the type including: a stator (2); a rotor (20) capable of moving in rotation in a plane (Pdm) called the mean movement plane perpendicular to a geometrical rotational axis (X1) on which the rotor (20) is centred; coupling means (8) for driving the rotor (20) arranged between the stator (2) and said rotor (20); piezoelectric means (12) capable of being electrically excited to impart a vibratory movement onto the coupling means (8); transmission means (40) able to transmit the vibratory movement from the coupling means (8) to the rotor (20) in order to drive said rotor (20) in rotation about its axis (X1), and holding means (44) for applying the rotor (20) onto the coupling means (8), characterised in that the coupling means (8) are arranged freely about the geometrical rotational axis (X1) on which they are centred, and in that the coupling means (8) rest on the stator (2) via support means (10) shaped to convert the vibratory movement of the point

Abstract: An ultrasonic motor has a stator and a rotor which is press fit to the stator and rotates in accordance with the vibration of the stator. The stator includes a pair of metal blocks, a piezoelectric element located between the metal blocks, a tightening member and a positioning member. The tightening member is inserted through the metal blocks and the piezoelectric element to tighten the metal blocks and the piezoelectric element in the axial direction. The positioning member determines the radial position of the metal blocks. This reduces misalignment of metal blocks and the tightening member, and the stator for the ultrasonic motor.

Abstract: An ultrastiff precision sonic bearing assembly and method thereof for controlling an effective coefficient of friction between two elements in slidable contact configured along an interface under a force sufficient to maintain contact and having static friction therebetween, by inducing a repetitive motion in one of the elements parallel to the interface thereby altering the effective coefficient of friction therebetween. The bearing assembly also provides for additional and independent electronic control over the average thickness thereof and senses the force thereon to allow the bearing assembly stiffness to be altered.

Abstract: A piezoelectric actuator comprises a plurality of piezoelectric elements stacked in a thickness direction thereof for undergoing expansion/contraction movement to vibrationally drive the piezoelectric actuator in accordance with a driving signal applied to the piezoelectric elements. Each of the piezoelectric elements has a length extending in a direction generally perpendicular to the stacking direction. The length of each of at least two of the piezoelectric elements being different from the length of at least one other of the piezoelectric elements.

Abstract: An ultrasonic motor includes a stator having a piezoelectric element and a rotor facing the stator. The piezoelectric element is annular and is polarized into segments in the circumferential direction. A flexible plate is fixed to the piezoelectric element with an electrode plate in between. The flexible plate includes a flexible substrate, a conductor, and a reinforcement. The conductor is located on a part of the flexible substrate to be electrically connected to the electrode plate. The reinforcement is located on the flexible substrate at a position that is off the conductor. The reinforcement suppresses vibration generated at a part of the piezoelectric element that is off the conductor, thereby stabilizing vibration of the piezoelectric element in the circumferential direction.

Abstract: There is disclosed a vibration member comprising: a driving portion; an elastic member including the driving portion; and an electro-mechanical energy conversion element as a driving source in contact with the elastic member. The electro-mechanical energy conversion element is provided with an alternating signal to generate a plurality of vibrations, and the plurality of vibrations are combined to generate a driving vibration in the driving portion. An ununiformity of rigidity of the vibration member caused by a polarization treatment performed on the electro-mechanical energy conversion element is offset by partially changing the rigidity of the vibration member, so that a stable driving vibration of the vibration member can be outputted.

Abstract: A vibration type actuator includes a vibration element having at least a first elastic element, a second elastic element, an electro-mechanical energy conversion element, and a shaft, and a relative moving member which relatively moves upon a vibration of the vibration element. The shaft has a flange portion and a fixing portion joined to a fixing member and clamps the first and second elastic elements by the flange and the nut while the conversion element is clamped between the first and second elastic elements.

Abstract: The present invention relates to a ring-type piezoelectric ultrasonic motor that is different from the electro-magnetically driven conventional motors and that has applications in robots and automation equipments. More specifically, the present invention relates to a ring-type piezoelectric ultrasonic motor that is driven by a frictional force between rotor and stator, and stator is produced a mechanical displacement by a piezoelectric ceramics applying an alternate electric field with an ultrasonic frequency (above 16 kHz).

Abstract: A vibration motor comprising at least one stationary part and one part driven to move relative to the fixed part, together with excitation that is suitable for exerting forces that tend to move rigid contact sectors presented by the fixed part and/or the moving part and to cause the rigid sectors to vibrate in vibration modes that combine tangential vibration and normal vibration, thereby driving the movement of the moving part, the motor presenting for the tangential vibration or the normal vibration a main resonant mode and at least one secondary resonant mode, wherein the secondary resonant mode is at a frequency that is substantially equal to a harmonic frequency of the main resonant mode.

Abstract: A drive mechanism has an ultrasonic motor having a rotor which is rotationally driven by vibration of a vibrating member having a piezoelectric element. The rotor has a projecting portion for rotation therewith. A driven member is connected to the rotor for undergoing movement along a surface extending in a radial direction of the rotor. A guide member restricts movement of the driven member and guides movement of the receiving member in a given direction. A receiving member contacts the projecting portion of the rotor to limit a range of rotation of the rotor and limit a range of movement of the driven member.

Abstract: A piezoelectric motor having a stator in which piezoelectric elements are contained in slots formed in the stator transverse to the desired wave motion. When an electric field is imposed on the elements, deformation of the elements imposes a force perpendicular to the sides of the slot, deforming the stator. Appropriate frequency and phase-shifting of the electric field will produce a wave in the stator and motion in a rotor. In a preferred aspect, the piezoelectric elements are configured so that deformation of the elements in the direction of an imposed electric field, generally referred to as the d33 direction, is utilized to produce wave motion in the stator. In a further aspect, the elements are compressed into the slots so as to minimize tensile stresses on the elements in use.

Abstract: In order to manufacture a vibration wave driving device in a short time and with high accuracy, the device of the invention comprises:

Abstract: In a method of producing an iron core by punching and laminating stator core pieces and rotor core pieces from the same metal sheet, it is an object of the invention that magnetic pole teeth of the roughly punched stator core pieces are caused to stably develop by pressing toward space sides made by previously punching the rotor core pieces so as to sufficiently secure punching margins for pressing out the front tips of the magnetic pole teeth of the internal forms of the stator core pieces and the punching can be performed without obstacles even if a gap with the rotor core pieces is small, and further ruggedness formed on a surface of the metal sheet by pressing does not cause disturbances in a flow of magnetic flux.

Abstract: An ultrasonic motor includes a stator, which includes a piezoelectric element, and a rotor, which opposes the stator. The piezoelectric element vibrates the stator to rotate the rotor. The rotor has an annular thin section. An elastic ring is secured to the thin section. The mass of the elastic ring is selected from a predetermined range of masses. The motor speed at which a predetermined level of noise is produced by the motor is substantially constant for the range of the masses. This reliably damps undesirable vibration of the motor.

Abstract: The conductor pattern on an ultrasonic motor lead board is prevented from being stripped off an ultrasonic motor lead board main body. An ultrasonic motor support member 124 for an ultrasonic motor 130 is firmly fixed on an ultrasonic motor shaft 132. A piezoelectric element 802 is firmly fixed to an ultrasonic stator main body 122b. The ultrasonic stator 122 is firmly fixed on the ultrasonic motor shaft 132. An ultrasonic motor lead board 136 is firmly fixed onto a backside of the ultrasonic motor support member 124. A conductor pattern 136b at its tip portion 136e and a conductor pattern 136b at its tip portion 136f are respectively welded to electrodes 803a, 803b of the piezoelectric element 802. An ultrasonic rotor 134 is arranged rotatable relative to the ultrasonic motor shaft 132. A pressurizing spring 138 puts the ultrasonic rotor 134 in pressure contact with the ultrasonic stator 122.

Abstract: A fixing member is inserted under pressure into a central hole of an ultrasonic vibrator, a case and a center axle are fixed by a screw, a bearing is fixed on an end portion of the center axle, a rotor is mounted to rotate by the bearing, a connection member is fixed to the rotor, projections are formed on the edge of a disk of the connection member, spaces are formed between the projections respectively, a contact member is composed by inserting ends of divided parts into spaces of the connection member, and a ring-like elastic member is mounted on the contact member which is pressed on the ultrasonic vibrator.

Abstract: A friction member is used in a friction portion in a vibration wave driving apparatus. The friction member comprises a composite resin which comprises polytetrafluoroethylene as a matrix and which further comprises at least an inorganic fiber substance and a heat-resistant resin. A ratio of a content Vf (vol %) of the inorganic fiber substance to a content Vr (vol %) of the heat-resistant resin satisfies the following relation: ⅓≦Vf/Vr≦3.

Abstract: A piezoelectric motor having a stator in which piezoelectric elements are contained in slots formed in the stator transverse to the desired wave motion. When an electric field is imposed on the elements, deformation of the elements imposes a force perpendicular to the sides of the slot, deforming the stator. Appropriate frequency and phase-shifting of the electric field will produce a wave in the stator and motion in a rotor. In a preferred aspect, the piezoelectric elements are configured so that deformation of the elements in the direction of an imposed electric field, generally referred to as the d33 direction, is utilized to produce wave motion in the stator. In a further aspect, the elements are compressed into the slots so as to minimize tensile stresses on the elements in use.

Abstract: An ultrasonic motor includes a stator having a piezoelectric element and a rotor facing the stator. The piezoelectric element vibrates the stator to rotate the rotor. A lining member is located between the rotor and the stator. A spring is installed in the motor. The spring is deformed by a predetermined amount to press the rotor against the stator. The force of the spring pressing the rotor changes in accordance with the deformation of the spring. The spring is installed such that its deformation is in a predetermined range, so that, within the range, the urging force of the spring changes by a relatively small amount for a given change of deformation. Therefore, when deformation of the spring changes due to wearing of the lining member, the urging force of the disk spring scarcely changes. Accordingly, the rotation characteristics of the motor scarcely change over time.

Abstract: An ultrasonic motor includes a stator, which includes a piezoelectric element, and a rotor, which opposes the stator. The piezoelectric element vibrates the stator to rotate the rotor. The rotor has an annular thin section. An elastic ring is secured to the thin section. The mass of the elastic ring is selected from a predetermined range of masses. The motor speed at which a predetermined level of noise is produced by the motor is substantially constant for the range of the masses. This reliably damps undesirable vibration of the motor.

Abstract: An ultrasonic motor driven by a self-oscillation circuit which can be mounted in an electronic device without imposing structural restrictions on the electronic device and can thus be used easily. Among an oscillating member for generating an oscillatory wave, a pressing mechanism for causing a moving body to make pressing contact with the oscillating member, a moving body frictionally driven by the oscillatory wave, and outputting means for transmitting an output from the moving body to the outside, at least one member is made of an insulating material, and when in particular the moving body is provided with outputting means for transmitting an output torque this outputting means is made of an insulating material and no restrictions are imposed on the shapes and the materials of the oscillating member and the moving body, which closely relate to the output performance of the ultrasonic motor.

Abstract: A piezoelectric motor having a stator in which piezoelectric elements are contained in slots formed in the stator transverse to the desired wave motion. When an electric field is imposed on the elements, deformation of the elements imposes a force perpendicular to the sides of the slot, deforming the stator. Appropriate frequency and phase shifting of the electric field will produce a wave in the stator and motion in a rotor. In a preferred aspect, the piezoelectric elements are configured so that deformation of the elements in direction of an imposed electric field, generally referred to as the d33 direction, is utilized to produce wave motion in the stator. In a further aspect, the elements are compressed into the slots so as to minimize tensile stresses on the elements in use.

Abstract: An ultrasonic motor includes a rotor and a rotor accommodated in a housing. The stator includes a piezoelectric element and the housing is secured to a base by screws. The rotor contacts the stator. The piezoelectric element vibrates the stator to rotate the rotor. An insulation plate is located between the stator and the base. An insulation washer is located between the stator and each screw. A rotary shaft is rotatably supported by the housing. The rotary shaft is coupled to the rotor with an insulation collar in between. Therefore, the stator and the rotor are electrically insulated from the housing and the rotary shaft. This arrangement reduces electromagnetic noise, which interferes with other electric devices, such as radios.

Abstract: A vibration wave apparatus includes a plurality of vibration member groups. Each vibration member group includes a plurality of vibration members having respective driving portions in which driving vibration waves are generated, where the respective driving portions are arranged at axially opposite sides of the vibration member group and the said plurality of vibration members are disposed coaxially with one another, and a holding member disposed between the respective driving portions of the plurality of vibration members, and arranged to support the vibration member group at a peripheral portion of the holding member.

Abstract: 2n (n is an integer) projections are formed per half wavelength on the driving surface of a vibration member of a disclosed vibration driven motor. The vibration member has an A driving electrode group (A1 to A8) and a B driving electrode group (B1 to B8) polarized at a &lgr;/2 pitch so as to alternately have opposing expansion/contraction polarities with respect to a wavelength &lgr; of a vibration wave to be excited, and &lgr;/4-pitch vibration detection electrodes (SA, SB) and three ground common electrodes (G), which are arranged between the A and B electrode groups. The vibration detection electrodes (SA, SB) are arranged to have substantially loop positions of standing waves generated by the corresponding A and B driving electrode groups as their centers.