Displacement connectors of high bending stiffness and piezoelectric actuators made of such

Abstract

Disclose displacement connectors of high bending stiffness, high-performance piezoelectric actuators and derivative devices made of such. The connector has circumferentially alternating recess housings which, when fitted with the intended piezoelectric active elements makes displacement actuators, approximately double (2x), triple (3x) or quadruple (4x) the displacement of individual active elements without adversely jeopardizing their regenerative forces. The connector may take any overall cross-section and length to suit intended applications. Connector recesses can be configured to house piezoelectric elements of a wide variety of cross-sections and dimensions, including longitudinal mode stacks, transverse mode bars and / or tubes, single crystal blocks of suitable cut and dimensions andtheir bonded assemblages. Derivative devices such as high-performance displacement actuators and compact Langevin low-frequency underwater projectors, can be made from such connectors.

Description

technical field [0001] The invention relates to a displacement connector with high bending rigidity, in particular to a high-efficiency piezoelectric actuator. Background technique [0002] Small, high-capacity and high-precision piezoelectric actuators are required in many technical fields including industry, aerospace, defense, medicine and science, that is, with relatively high displacement (≥60μm) and braking force (≥50N) And a piezoelectric actuator with minimum hysteresis. See "The Shock and Vibration Digest", Vol. 33 (2001), pp. 269-280, entitled "Piezoelectric actuation: state of the art", Niezrecki, C. et al.). [0003] Direct Push-Pull Piezoelectric Actuators include longitudinal (d 33 ) stack tube actuator and transverse (d 31 ) of the tube actuator. It usually has a large braking force of about >100 N but a low displacement of <40 μm. To obtain displacements >40 μm, stacks consisting of hundreds of layers and measuring over 100 mm in height are comm...

AI Technical Summary

Problems solved by technology

[0011] However, all displacement-enhancing mechanisms of the state-of-the-art suffer from high bending compliance, seriously compromising the effectiveness of the obtained actuators

[0012] Due to the large bending compliance of the mechanical connector used for displacement enhancement, the displacement and braking force of the device constituted by the above displacement enhancement mechanism is adversely affected

[0013] However, stacked actuators and thus active elements with solid triangular cross-sections have not been available so far, possibly because of their weak sharp corners and high manufacturing costs

Similarly, lateral-mode active elements with triangular tube cross-sections have not been available so far

Images