초록 ▼

An actively controlled helicopter rotor blade includes a trailing edge flap actuated by a fast-acting actuator. A lightweight, rugged, fast-acting actuator suitable for use as the flap actuator comprises a pair of column actuators composed of a smart material such as piezoelectric, magnetostrictive,

An actively controlled helicopter rotor blade includes a trailing edge flap actuated by a fast-acting actuator. A lightweight, rugged, fast-acting actuator suitable for use as the flap actuator comprises a pair of column actuators composed of a smart material such as piezoelectric, magnetostrictive, shape memory alloy or other material that exhibits a shape change when subjected to an external stimulus. Each of the column actuators is composed of multiple piezoelectric ceramic actuator elements bonded together to form the individual columns. Each of the column actuators engages the base of an actuator tube that, in turn, is urged against the column actuators by a tension member. Differential voltage applied to the columns causes a differential elongation of the column actuators, which causes the actuator tube to pivot about an axis proximal the tips of the column actuators. The movement of the actuator tube is coupled by a linkage to the rotor blade flap. Spherical joints are disposed between the column actuators and the actuator tube to prevent transmission of substantial bending loads to the column actuators and a mid-point support is also provided for each of the column actuators to limit the magnitude of acceleration induced bending loads, which would otherwise lead to tensile failure of the ceramic actuator elements.

대표청구항 ▼

[ What is claimed is:] [1.] An apparatus for providing helicopter rotor blade active control comprising:a helicopter rotor blade comprising an airfoil having a leading edge and a trailing edge, said airfoil having an interior volume;a flap disposed proximal said trailing edge;a hinge attaching said

[ What is claimed is:] [1.] An apparatus for providing helicopter rotor blade active control comprising:a helicopter rotor blade comprising an airfoil having a leading edge and a trailing edge, said airfoil having an interior volume;a flap disposed proximal said trailing edge;a hinge attaching said flap to said rotor blade, said flap being pivotable about said hinge to provide variations in lift generated by said rotor blade;an actuator mounted to said rotor blade and housed within said interior volume, said actuator comprising a smart material capable of changing shape in response to an external stimulus, said actuator comprises first and second column actuator members, each of said first and second column actuator members comprising a plurality of individual actuator elements disposed adjacent one another to form a columnar structure having proximal and distal ends and a longitudinal axis, said first and second column actuator members being disposed in a substantially parallel configuration,said actuator further comprises third and fourth column actuator members, each of said third and fourth column actuator members comprising a plurality of individual actuator elements disposed adjacent one another to form a columnar structure having proximal and distal ends and a longitudinal axis, said third column actuator member disposed coaxially with said first column actuator member, said fourth column actuator member disposed coaxially with said second column actuator member;a center support disposed between said first column actuator member and said third column actuator member, said first and third column actuator members compressively engaging said center support, said center support providing resistance to lateral movement of said first and third column actuator members;an actuator tube, said actuator tube having a base compressively engaging said first and second column actuator members, said actuator tube being adapted to rotate about an axis normal to said column actuator members in response to differential elongation of said first and second column actuator members, said actuator tube further including an output end; anda linkage disposed between said actuator and said flap, said linkage adapted to cause said flap to pivot about said hinge in response to movement of said actuator tube, and said output end of said actuator tube engaging said linkage for causing said flap to rotate in response to rotational movement of said actuator tube.