Nikon Corporation

Michihiro Tobe

Tadao Takagi

Tunemi Gonda

Tsuyoshi Matsumoto

Takatoshi Ashizawa

Mitsuhiro Okazaki

Daisuke Saya

Tsutomu Narisawa

Mina Kobayashi

Mine Shibata

A driving device is equipped with a vibration actuator. The vibration actuator includes a roller element, an elastic member and electro-mechanical converting elements, which contact the elastic member. The electro-mechanical converting elements generate a vibration to drive the elastic member. Additionally, the roller element transfers relative movement to at least one element to be moved by contacting a driving part of the vibration actuator and by rotating. The roller element comprising a first part contacting the at least one driving section of the elastic member and a second part, separate from the first part, contacting the at least one element. In operation, the at least one electro-mechanical converting element vibrates the at least one driving section of the elastic member. The at least one driving section transfers the vibration to the first part of the roller element to rotate the roller element and the least one element is moved by rotation of the second part of the roller element.

Vibration actuator drive device and method of use

A vibration actuator drive device using a linear type of ultrasonic actuator to drive a rotary member with high accuracy and good efficiency. The vibration actuator drive device includes an ultrasonic actuator which, by applying drive signals, produces longitudinal vibration and bending vibration to generate a drive force, and a rotary member in contact with the ultrasonic actuator. The combination of longitudinal vibration and bending vibration in the ultrasonic actuator generates relative motion in the rotary member having a circular locus of predetermined width. A compression mechanism causes compressive contact of the ultrasonic actuator with the rotary member. The longitudinal vibration vibrates in a direction about parallel to the direction of the drive force, and the bending vibration vibrates in a direction intersecting the longitudinal vibration. A drive force is transmitted to the rotary member at the inner circumferential side of the circular locus, and greatly differs from the drive force which is transmitted to the rotary member at the outer circumferential side. A lens barrel including a vibration actuator drive device drives a focus adjustment lens group in the optical axis direction by the conversion of the rotary motion of the rotary member to linear motion.

Vibration actuator and lens barrel

A vibration actuator produces a driving force by generating elliptic motion in the surface of an elastic member through electromechanical converting elements. The vibration actuator then generates relative motion between the elastic member and a relative moving member which is in compressive contact with the elastic member The electro-mechanical converting elements, in the form of piezoelectric elements, generate longitudinal vibrations and bending vibrations in the elastic member. The elastic member has a rectangular plate shape and includes a plurality of driving force output units which contact the relative moving member. Plural sliding members are respectively mounted on portions of the plurality of driving force output units such that the sliding members do not fully extend across the driving force output units in a short side direction.

Vibration actuator

A vibration actuator is provided with a rectangular parallelepiped elastic member of which a surface bears electromechanical converting elements adhered thereto and a relative moving member maintained in pressure contact with the other surface of the elastic member. A driving voltage is applied to excite the electromechanical converting elements to generate, in the elastic member, a longitudinal vibration vibrating in a plane parallel to the surface of the elastic member contacting the relative moving member and a bending vibration vibrating in a direction crossing the contacting surface, thereby generating a relative motion between the elastic member and the relative moving member. The elastic member has working portions for adjusting the difference of the resonance frequencies of the longitudinal and bending vibrations.

Vibration Actuator and adjustment method therefor

A vibration actuator is provided which is capable of generating a bending vibration having a sufficient amplitude to allow production of a large driving force in a direction perpendicular to the axis of the bending vibration. Specifically, the vibration actuator generates a primary mode longitudinal vibration and a fourth mode bending vibration harmonically in an elastic body, so that a portion of the elastic body having a driving protrusion moves cyclically along an elliptical path. The driving protrusion comes into contact with a relative moving body along a section of the elliptical path, and thus exerts a driving force on the relative moving body. Reduced rigidity portions formed in the elastic body preferably at positions corresponding to antinodes of the bending vibration allow the bending vibration, and therefore also the driving force, to have greater amplitudes.

Vibration acutuator

A vibration actuator includes a vibration member constituted by two substantially semi-cylindrical elastic members, a relative moving member disposed on an end face of the vibration member, a first electro-mechanical converting element for generating a torsional vibration about the axis of the vibration member, a second electro-mechanical converting element for generating a longitudinal vibration in the axial direction of the vibration member, a pressing member for making the relative moving member and the vibration member press contact with each other, and a support member the outer circumferential portion of the vibration member to protrude therefrom in the radial direction of the vibration member, and which supports the vibration member.

A vibration linear motor utilizing a composite vibration of a bending vibration and a longitudinal vibration, provided with a plate-shaped elastic member having a plate-shaped main body portion and a pair of driving force output portions provided on the surface of the main body portion for driving a driven object; and an electromechanical converting element adhered to the elastic member and adapted to generate the composite vibration, wherein the electromechanical converting element is provided on the surface, between the paired driving force output portions, of the main body portion.

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Yokohama, Japan

Michihiro Tobe