US 12,351,300 B2
Anti-resonance system for variable speed rotors
Ruthvik Chandrasekaran, Los Angeles, CA (US); Dewey H. Hodges, Atlanta, GA (US); and David J. Hodges, Dallas, GA (US)
Filed by Ruthvik Chandrasekaran, Los Angeles, CA (US); David J. Hodges, Dallas, GA (US); and Margaret E. Hodges
Filed on Jul. 9, 2024, as Appl. No. 18/767,974.
Application 18/767,974 is a continuation in part of application No. 18/514,175, filed on Nov. 20, 2023, abandoned.
Claims priority of provisional application 63/427,180, filed on Nov. 22, 2022.
Prior Publication US 2024/0359794 A1, Oct. 31, 2024
Int. Cl. B64C 27/00 (2006.01); B64C 27/04 (2006.01); B64C 27/68 (2006.01)
CPC B64C 27/001 (2013.01) [B64C 27/68 (2013.01); B64C 2027/004 (2013.01); B64C 27/04 (2013.01)] 10 Claims
OG exemplary drawing
 
1. An anti-resonance system for a blade defining an elongated channel therein and affixed to a helicopter rotor, the elongated channel having a length, the anti-resonance system comprising:
(a) an elongated cradle that runs along the length of the elongated channel;
(b) an elongated threaded rod disposed within the elongated channel and supported by the elongated cradle;
(c) a moveable mass disposed around both the elongated cradle and the elongated threaded rod within the elongated channel, the moveable mass including a threaded portion that is engaged with the elongated threaded rod so that rotation of the threaded rod causes lateral movement of the moveable mass; and
(d) a controller configured to cause the moving device to move the moveable mass to a selected position within the elongated channel so as to avoid the resonance vibrations of the blade during a rotor speed change;
(e) an actuator that is responsive to the controller and that rotates the elongated threaded rod to move the moveable mass to the selected position,
wherein changing a position of the moveable mass changes the blade natural frequency so as to move resonance points actively out of rotor operating speed, thereby reducing blade vibrations.