US 12,330,776 B2
Tunable mass damper assembly for a rotor blade
John C. Cox, Jupiter, FL (US); Steven P. Lozano, Stratford, CT (US); David H. Hunter, Stratford, CT (US); Emmett Emile Menair, Stratford, CT (US); Jacob Adam Fehrman, Stratford, CT (US); and John Devin Carroll, Fortworth, TX (US)
Assigned to LOCKHEED MARTIN CORPORATION, Bethesda, MD (US)
Filed by LOCKHEED MARTIN CORPORATION, Bethesda, MD (US)
Filed on Apr. 16, 2021, as Appl. No. 17/233,360.
Prior Publication US 2022/0332409 A1, Oct. 20, 2022
Int. Cl. B64C 27/00 (2006.01); B64C 27/10 (2023.01); B64C 27/473 (2006.01)
CPC B64C 27/001 (2013.01) [B64C 27/10 (2013.01); B64C 27/473 (2013.01); B64C 2027/005 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A tunable mass damper assembly attachable to a rotor blade configured to rotate about a rotor axis, the tunable mass damper assembly comprising:
a base configured to be attached to the rotor blade; and
a pendulum mass structure comprising:
a first end rotatably coupled to the base about a pivot axis substantially perpendicular to a plane containing the rotor axis;
a second end configured to rotate freely and without restraints on motion between two end stops about the pivot axis in accordance with a rotational speed of the rotor blade about the rotor axis, wherein when the base is attached to the rotor blade, the pendulum mass structure is coupled to the rotor blade only via the first end,
the pendulum mass structure being configured to reduce vibratory forces of the rotor blade induced by a rotation of the rotor blade about the rotor axis, and
an entirety of the pendulum mass structure being configured to be contained within and enclosed by the rotor blade.