Ultrasonic vibration device and ultrasonic medical device

Abstract

An ultrasonic vibration device (2) and an ultrasonic medical device provided with the ultrasonic vibration device (2), the ultrasonic vibration device (2) having a plurality of piezoelectric single crystal plates ( 44a to 44f), the direction of the maximum strain deformation is aligned with the direction perpendicular to the voltage application direction from the electrodes (45a, 45b) sandwiched on the plurality of piezoelectric single crystal plates, and the plurality of piezoelectric single crystal plates (44a to 44f) are stacked.

Description

technical field [0001] The present invention relates to an ultrasonic vibrating device that excites ultrasonic vibrations, and an ultrasonic medical device that includes the ultrasonic vibrating device. Background technique [0002] In recent years, ultrasonic medical devices including ultrasonic transducers have been known. Ultrasonic medical devices include an ultrasonic diagnostic device for imaging a state in a living body, an ultrasonic scalpel for coagulation and cutting during surgery, and the like. Among these devices, piezoelectric materials are used for ultrasonic vibrators that generate ultrasonic vibrations based on electrical signals, and piezoelectric ceramics and piezoelectric single crystals typified by PZT (lead zirconate titanate) are used. In addition, for the purpose of lowering impedance and increasing power, a structure in which a plurality of piezoelectric materials are stacked is used. [0003] As an ultrasonic vibrator in which piezoelectric single...

AI Technical Summary

Problems solved by technology

[0005] However, for some piezoelectric single crystal materials, the lamination direction does not become the axis of rotational symmetry, and the piezoelectric constant and the strain method are different depending on the direction.

For example, in a Langevin vibrator in which at least two or more piezoelectric single crystal materials whose stacking direction does not serve as an axis of rotational symmetry are stacked, and the polarization components in the stacking direction are alternately reversed, the surface of each piezoelectric element, Since the reverse side is alternately reversed and stacked, there are piezoelectric vibrators in which the deformation in the in-plane direction perpendicular (orthogonal) to the lamination direction, that is, the deformation in the in-plane direction of the piezoelectric vibrator is adjacent to all directions. consistent issues between

In addition, in the conventional Langevin vibrator, since the strain in the in-plane direction is inconsistent between adjacent piezoelectric vibrators, the deformation in the in-plane direction is hindered. In terms of input voltage, the smaller the interlayer, the excess stress acts on it and it is easy to break, and it may be damaged during driving.

Images