초록 ▼

A rotary actuator (18) is provided, including an actuator assembly (20). The actuator assembly includes a torque tube (24) formed of a shape memory alloy, a super elastic NiTinol return spring (26) having a proximal end (46) and a distal end (44), and a torque tube heating element (30) positioned ne

A rotary actuator (18) is provided, including an actuator assembly (20). The actuator assembly includes a torque tube (24) formed of a shape memory alloy, a super elastic NiTinol return spring (26) having a proximal end (46) and a distal end (44), and a torque tube heating element (30) positioned near the torque tube. The torque tube (24) includes a proximal end (32) and a distal end (34). The return spring and torque tube are connected at their ends, with the torque tube being pretwisted while in a martensitic state relative to the spring. Activation of the heating element causes the torque tube to enter an austenitic state in which it returns to its previous untwisted configuration. Removal of heat allows the torque tube to return to a martensitic state, further allowing the return spring to retwist the torque tube. Further provided is a unique locking assembly (22) for use with the actuator assembly. Further provided is a helicopter blade twist rotation system for use with a rotor craft blade (200) having a blade root (202) and a tip (204). The system includes a shape memory alloy rotary actuator (18) located within the blade near the blade root, and a passive torque tube (206) located within the blade and having a proximal end connected to the rotary actuator and a distal end connected to the blade near to the blade tip.

대표청구항 ▼

[ The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:] [1.] A rotary actuator for rotating an object, the rotary actuator comprising:(a) a torque tube formed of a shape memory alloy, the torque tube having a proximal end and a distal end;(b

[ The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:] [1.] A rotary actuator for rotating an object, the rotary actuator comprising:(a) a torque tube formed of a shape memory alloy, the torque tube having a proximal end and a distal end;(b) a super elastic return spring having a proximal end connected to the torque tube proximal end and a distal end connected to the torque tube distal end; the torque tube being longitudinally twisted relative to the super elastic return spring; and(c) a torque tube heating element positioned near the torque tube;wherein heating of the heating element causes the torque tube to enter an austenitic state in which the torque tube returns to its previous untwisted configuration; and wherein removal of heat allows the torque tube to return to a martensitic state thereby allowing the super elastic return spring to retwist the torque tube. [17.] A helicopter blade twist rotation system for use with a helicopter blade having a blade root end, a blade tip end, and a longitudinal spar extending from the blade root end toward the blade tip, the system comprising:(a) a shape memory alloy rotary actuator adapted to be connected to the blade spar near the blade root; and(b) a torsionally flexible passive torque tube adapted to be connected to the blade spar, the passive torque tube having a proximal end connected to the rotary actuator and a distal end connected to the blade near to the blade tip;wherein rotation of the rotary actuator causes like rotation of the torque tube proximal end and rotation of the torque tube distal end of an amount less than the rotation angle of the torque tube proximal end. A helicopter blade rotation system according to claim 17, wherein the shape memory rotary actuator is rotated by an amount up to 70 degrees to cause a rotation of the passive torque tube distal end by an amount up to 20 degrees. A helicopter blade rotation system according to claim 17, wherein the passive torque tube is formed from a material in the group comprising a metal and a structural composite.