Patent ID: 6717333
Filing Date: 2004-04-06
Classification: B64C,H02N,Y02T

Abstract:
A piezoelectric actuating device for controlling a flap on a rotor blade of a helicopter, comprising:a piezo element arrangement including at least one piezoelectric stack actuator; a power transmission frame coupled to the piezo element arrangement, the power transmission frame including an abutment and a driven element and generating a force therebetween from a change in length of the piezo element arrangement upon an excitation thereof, the force acting transversely to a direction of a centrifugal force of the rotor blade; a first holding device including a pair of first flexible straps extending substantially parallel to each other in the direction of the centrifugal force and configured to fix the power transmission frame relative to the rotor blade in the direction of the centrifugal force and to allow the power transmission frame to move relative to the rotor blade transversely to the direction of the centrifugal force within a limited range, the pair of first flexible straps being configured to perform a first parallelogram movement; and a second holding device including a pair of second flexible straps extending substantially parallel to each other transversely to the direction of the centrifugal force and configured to fix the abutment relative to the rotor blade transversely to the direction of the centrifugal force and to allow the abutment to move relative to the rotor blade in the direction of the centrifugal force within a limited range, the pair of second flexible straps being configured to perform a second parallelogram movement.