초록 ▼

A piezoelectric actuator includes a plurality of linearly axially expandable hard piezoelectric rods located between two plates and are distributed about a central twistable core fastened between the plates, with the axis of the rod skew to the axis of the core, resembling a squirrel cage. The actua

A piezoelectric actuator includes a plurality of linearly axially expandable hard piezoelectric rods located between two plates and are distributed about a central twistable core fastened between the plates, with the axis of the rod skew to the axis of the core, resembling a squirrel cage. The actuator produces a twisting movement between the plates, responsive to voltage induced expansion of those piezoelectric rods. Fly by Wire aircraft control is realized with the actuator in various systems providing all electric control of aerodynamic surfaces, including an electronic helicopter swashplate by which the effective pitch of the main rotor blade is controlled.

대표청구항 ▼

An electromechanical transducer, comprising: a cylindrical shaped core, said core being torsionally flexible and longitudinally stiff, said core further defining an axis and having first and second ends; first and second end support plates fixed to the respective ends of said core, each said end pla

An electromechanical transducer, comprising: a cylindrical shaped core, said core being torsionally flexible and longitudinally stiff, said core further defining an axis and having first and second ends; first and second end support plates fixed to the respective ends of said core, each said end plate including a peripheral portion extending radially outward beyond the outer surface of said core; a plurality of elongate rods of piezoelectric material, said plurality being equal to the integral number N, said rods being positioned about said core in non-intersecting relationship and skew to said core axis, with all of said rods being inclined at the same angle to said first support plate as measured in a counterclockwise direction about said core axis; said elongate rods having first and second ends attached respectively to said first and second end plates; each said rod being axially expandable to increase in length, responsive to and in dependence upon application of voltage of a first polarity applied between said rod ends, whereby one of said support plates rotationally moves through a circular arc relative to the other of said support plates.