Abstract: It is an subject of the present invention to provide a vibration actuator in which a plurality of rotors can be driven by a single vibration unit. When a composite vibrator (2) is driven to generate a composite vibration combining a plurality of vibrations, a first stator (3) and a second stator (4) vibrate, thereby causing elliptical movements in corner portions (8) and (9) of the first stator (3) and the second stator (4), respectively. As a result, a first rotor (A) abutting onto and pressurized against the corner portion (8) of the first stator (3) and a second rotor (B) abutting onto and pressurized against the corner portion (9) of the second stator (4) are rotated at the same time. Further, in this case, by selecting vibration modes of the plurality of vibrations constituting the composite vibration, the two rotors (A) and (B) can be rotated in the same direction or in opposite directions with respect to each other.

Abstract: It is an subject of the present invention to provide a vibration actuator in which a plurality of rotors can be driven by a single vibration unit. When a composite vibrator (2) is driven to generate a composite vibration combining a plurality of vibrations, a first stator (3) and a second stator (4) vibrate, thereby causing elliptical movements in corner portions (8) and (9) of the first stator (3) and the second stator (4), respectively. As a result, a first rotor (A) abutting onto and pressurized against the corner portion (8) of the first stator (3) and a second rotor (B) abutting onto and pressurized against the corner portion (9) of the second stator (4) are rotated at the same time. Further, in this case, by selecting vibration modes of the plurality of vibrations constituting the composite vibration, the two rotors (A) and (B) can be rotated in the same direction or in opposite directions with respect to each other.

Abstract: An apparatus levitates and transports an object. The apparatus levitates the object above the surfaces of a plurality of vibrators by air pressure of sound waves that are generated by the vibrators. The apparatus has a plurality of vibration devices, each of which corresponds to one of the vibrators. Each vibration device includes a first transducer for vibrating the corresponding vibrator. Each transducer includes a super-magnetostrictive material. A common power source is connected to at least two of the first transducers for actuating the first transducers.

Abstract: An apparatus for levitating and transporting an object includes a pair of elongated vibrators, a pair of oscillators and a pair of flection limiting rods. Each oscillator includes a horn and a transducer and corresponds to one of the vibrators. Each transducer vibrates the corresponding vibrator through the corresponding horn to generate sound waves from the vibrator. The object is levitated by radiation pressure of the sound waves. Each flection limiting rod corresponds to one of the vibrators. Each rod contacts the lower surface of the corresponding vibrator at a position where the displacement due to vibration is relatively small and reduces the flection of the vibrator due to the weight of the vibrator and the weight of the transported object.

Abstract: A method of controlling an object levitating apparatus is disclosed. The levitating apparatus levitates an object on a plurality of vibrating bodies with air pressure generated from sound waves produced by the vibrating bodies. Each vibrating body is vibrated by a corresponding vibrating apparatus. Each vibrating apparatus has an oscillator and a transducer. The transducer is actuated by the oscillator to vibrate the corresponding vibrating body. The method includes determining impedance of each transducer, and controlling each oscillator in accordance with the determined impedance to restrict displacement of the levitated object.

Abstract: An apparatus for levitating and transporting an object includes a pair of elongated vibrators, a pair of oscillators and a pair of flection limiting rods. Each oscillator includes a horn and a transducer and corresponds to one of the vibrators. Each transducer vibrates the corresponding vibrator through the corresponding horn to generate sound waves from the vibrator. The object is levitated by radiation pressure of the sound waves. Each flection limiting rod corresponds to one of the vibrators. Each rod contacts the lower surface of the corresponding vibrator at a position where the displacement due to vibration is relatively small and reduces the flection of the vibrator due to the weight of the vibrator and the weight of the transported object.

Abstract: An apparatus levitates and transports an object. The apparatus levitates the object above the surfaces of a plurality of vibrators by air pressure of sound waves that are generated by the vibrators. The apparatus has a plurality of vibration devices, each of which corresponds to one of the vibrators. Each vibration device includes a first transducer for vibrating the corresponding vibrator. Each transducer includes a super-magnetostrictive material. A common power source is connected to at least two of the first transducers for actuating the first transducers.

Abstract: A method of controlling an object levitating apparatus is disclosed. The levitating apparatus levitates an object on a plurality of vibrating bodies with air pressure generated from sound waves produced by the vibrating bodies. Each vibrating body is vibrated by a corresponding vibrating apparatus. Each vibrating apparatus has an oscillator and a transducer. The transducer is actuated by the oscillator to vibrate the corresponding vibrating body. The method includes determining impedance of each transducer, and controlling each oscillator in accordance with the determined impedance to restrict displacement of the levitated object.

Abstract: A bone assessment apparatus for obtaining an assessment value E for a bone 12 with good repeatability by simple calculation using the waveform of a signal derived from received ultrasound which has passed through the bone. A transmitting transducer (20) transmits an ultrasound pulse. A receiving transducer (22) receives the ultrasound pulse which has passed through a test sample (10), and then converts the received ultrasound pulse to a signal. An A/D converter (30) digitizes the signal amplified in a receiving amplifier (28). The digitized signal is inputted to a calculator (32) via a transducer controller (26). The calculator (32) calculates the assessment value E for the bone (12) from characteristic values of the waveform of the signal, such as the half-value width of the first positive portion, which are derived from ultrasonic transmission characteristics of the bone (12).

Abstract: An ultrasonic motor including a driving member and a driven member, the driving member comprising a plate- or rod-like elastic member, a flexural vibrator fixed to the elastic member and causing the elastic member to induce a standing wave type flexural vibration upon application of an AC voltage thereto, and a longitudinal vibrator provided on a node line of the flexural vibration at the surface of the elastic member, the longitudinal vibrator being pivoted about the node line by the flexural vibrator and adapted to expand and contract in an amplitude direction of the flexural vibration upon application of an AC voltage thereto, the driven member being brought into pressure contact with an end face of the longitudinal vibrator. The longitudinal vibrator is expanded or contracted in synchronism with the flexural vibration, whereby the driving member and the driven member are moved relatively to each other.

Abstract: An ultrasonic motor including a driving member and a driven member, the driving member comprising a plate- or rod-like elastic member, a flexural vibrator fixed to the elastic member and causing the elastic member to induce a standing wave type flexural vibration upon application of an AC voltage thereto, and a longitudinal vibrator provided on a node line of the flexural vibration at the surface of the elastic member, the longitudinal vibrator being pivoted about the node line by the flexural vibrator and adapted to expand and contract in an amplitude direction of the flexural vibration upon application of an AC voltage thereto, the driven member being brought into pressure contact with an end face of the longitudinal vibrator. The longitudinal vibrator is expanded or contracted in synchronism with the flexural vibration, whereby the driving member and the driven member are moved relatively to each other.

Abstract: An ultrasonic motor has a longitudinal-torsional composite transducer, a stator constituted by an ultrasonic vibrator sandwiching the transducer, and a rotor urged against the stator. The stator excites longitudinal-torsional ultrasonic vibrations to rotate the rotor by a frictional force. The motor includes a vibration adjusting rod for matching resonance frequencies of longitudinal and torsional ultrasonic vibrations of the stator with each other.

Abstract: A paper feeding apparatus comprises a flexible vibrating body made of an elastic matter. The body is excited with a resonant frequency so as to produce a progressive wave. A driving vibrator is fixed to one end of the flexible vibrating body, and a receiving vibrator is fixed to the other end thereof. A mechanism is included for urging paper against the flexible vibrating body, so that when the vibrating body is excited, the paper is conveyed.

Abstract: An ultrasonic driven type motor in which an ultrasonic torsional vibrator is activated to generate a forward turning torque for driving a rotor synchronously with the expansion of at least one piezoelectric actuator provided between the vibrator and the rotor, and to generate a return turning torque synchronously with the constriction of the piezoelectric actuator, and the piezoelectric actuator has a coupling control characteristic so that only the forward turning torque is selectively transmitted to the rotor.

Abstract: A vibration wave motor includes circular shape vibration part having a helical stepped portion inside or outside thereof; a unit, coupled to said vibration part for causing the vibration part to generate a travelling vibration wave propagating along a circumferential direction of the vibration part; and a movable part having a stepped portion threadably engaged with the helical stepped portion, the movable part being frictionally driven by the travelling vibration wave generated by the vibration part.

Abstract: A rotary driver is disclosed, which comprises a solenoidal oscillation element consisting of an electrostriction element polarized in radial directions or vertical directions and provided with electrodes on pair opposite surfaces perpendicular to the direction of polarization. The electrode on either one of the pair opposite surfaces is uniformly divided by x greater than four. AC voltages of V.sub.o sin .omega.t shifted in phase from each other by 2.pi./x are applied to the division electrodes. A driven member is held in contact with at least one of the opposite surfaces of the solenoidal oscillation element.