Olympus Corporation

Nagahide Sakai

Tomoki Funakubo

Yasuaki Kasai

Yoshihiro Ue

Hiromichi Sakano

Junji Okada

Makoto Harada

Morimiti Simizu

An ultrasonic vibrator and an ultrasonic treatment device which can adjust a resonant frequency while maintaining driving force are provided. An ultrasonic vibratorincludes two metal blocks, a driving unitthat is arranged between the metal blocksand produces a piezoelectric effect to vibrate by application of an alternating voltage, and at least one adjustment unitthat is arranged between the metal blocksand the driving unitin an insulated state and changes Young's modulus.

Ultrasonic vibrator and ultrasonic treatment device

In manufacturing method of a cylindrical piezoelectric element, a cylindrical piezoelectric material is formed by molding a piezoelectric material into a cylindrical shape and subjecting the molded piezoelectric material to calcination. A reference electrode is provided on an inner circumferential surface of the cylindrical piezoelectric material. Drive electrodes are provided in a circumferential direction so that the drive electrodes are extending in an axial direction from one end to the other end on an outer circumferential surface. A polarization electrode is provided at a part of the circumferential surface in the vicinity of the one end. A predetermined voltage is applied between the polarization electrode and the reference electrode. The polarization electrode is removed from the cylindrical piezoelectric material.

Method of manufacturing cylindrical piezoelectric element

An ultrasonic motor drive apparatus comprises a piezoelectric elementhaving a plurality of piezoelectrically active regions, in which longitudinal vibration and flexural vibration are induced with application of alternate signals to the plurality of piezoelectrically active regions, a piezoelectric element holderthat is fixedly attached to the piezoelectric element, covering the neighborhood of a common node of the longitudinal vibration and the flexural vibration induced in the piezoelectric element all along the circumference of the central portion of the piezoelectric element with respect to the longitudinal direction, a vibrator holderhaving a plurality of openings, a driven memberhaving a substantially spherical shape, an output shaftattached to the driven member, through which power output of the driven member is transmitted, a pressing memberthat brings the driven memberand the piezoelectric member into pressure contact with each other along the third direction, a caphaving an opening, a link memberone end of which is connected with the pressing memberalong the third direction and the other end of which can be connected with another apparatus, and a control sectionthat applies an alternate signal to the piezoelectric member.

Ultrasonic motor drive apparatus

An ultrasonic motor, which drives a driven member using an elliptical vibration produced by synthesizing a longitudinal vibrational mode and a flexural vibrational mode as a drive force, is configured as follows. Namely, the ultrasonic motor includes a piezoelectric device, and a feed member feeding the piezoelectric device. An extensional axis of the feed member is set to an axis different from main vibrational axes of the longitudinal vibrational mode and the flexural vibrational mode.

Ultrasonic motor

When a piezoelectric ceramic sheet is divided into two equal parts in a longitudinal direction and two equal parts in a width direction to form four regions, internal electrodes are disposed over each region and are disposed so that surface areas occupied in each region are substantially the same, and a longitudinal vibration is detected based on a potential difference between the internal electrodes.

Ultrasonic motor and vibration detection method for ultrasonic motor

An ultrasonic motor includes a vibrator formed by stacking a plurality of rectangular piezoelectric plates in a thickness direction, a driving circuit for applying a driving signal to a piezoelectric plate, and a detection circuit for detecting an electromotive force generated when the piezoelectric plate deforms, and this ultrasonic motor is configured in such a manner that there are a first piezoelectric plate and a second piezoelectric plate among the plurality of rectangular piezoelectric plates, the first and the second piezoelectric plate each is a piezoelectric plate in which a longitudinal vibration polarization portion that can excite longitudinal vibrations and a bending vibration polarization portion that can excite bending vibrations are polarized in a thickness direction, and the first piezoelectric plate is connected to the driving circuit and the detection circuit, and the second piezoelectric plate is connected to the driving circuit and is not connected to the detection circuit.

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Tokyo, Japan

Nagahide Sakai