Precision blade pitch adjustment
AssigneeTextron Innovations Inc.
InventorsAndrew Paul Haldeman, Michael Seifert, Timothy McClellan Mosig, Aaron Acee, Diana R. Tinlin, Andrew Thomas Carter, Glenn Thornton Lancaster
Life of this patent
Estimating the term…
Abstract
A blade pitch adjustment mechanism includes a pitch cylinder having a first face and pitch slots extending longitudinally from the first face, a blade sleeve having a second face and a blade slot extending longitudinally from the second face, the blade sleeve is configured to be rotationally positioned in the pitch cylinder with the second face located with the first face, wherein the blade slot and the pitch slots are cooperative to form keyway, corresponding to a discrete blade pitch, when the blade slot is aligned with a pitch slot.
Claims16
A blade pitch adjustment mechanism for fixing a rotor blade to a rotor hub, the blade pitch adjustment mechanism comprising:
- a pitch cylinder having a first face and pitch slots extending longitudinally from the first face, and a pitch plate circumscribing the first face, wherein the first face is recessed inboard from the pitch plate;
- a blade sleeve having a second face and a blade slot extending longitudinally from the second face, the blade sleeve configured to be rotationally positioned in the pitch cylinder with the second face located with the first face;
- and
- the blade slot is cooperative with each pitch slot of the pitch slots to form keyways, whereby a keyway of the keyways is opened at the each pitch slot when the blade slot is circumferentially aligned with the each pitch slot.
A rotor blade assembly, comprising:
- a hub having a rotational axis and an outboard wall parallel to the rotational axis;
- a pitch cylinder fixed to the hub and extending inboard with a first face exposed at the outboard wall, and a pitch plate positioned at the outboard wall and circumscribing the first face, wherein the first face is recessed inboard from the pitch plate;
- pitch slots spaced circumferentially and extending inboard from the first face;
- a blade sleeve fixed to a blade and positioned in the pitch cylinder with a second face located at the outboard wall;
- a blade slot extending inboard from the second face, wherein the blade slot is cooperative with each pitch slot of the pitch slots to form keyways, wherein each keyway of the keyways is formed at the each pitch slot when the blade slot is circumferentially aligned with the each pitch slot;
- and
- a key configured to be disposed in the keyway thereby fixing the blade sleeve to the pitch cylinder.
A method, comprising:
- adjusting a blade pitch in a rotor blade assembly comprising a hub having a rotational axis and an outboard wall parallel to the rotational axis, a pitch cylinder fixed to the hub and extending inboard from a first face, pitch slots spaced circumferentially and extending inboard from the first face, a pitch plate positioned at the outboard wall and circumscribing the first face, wherein the first face is recessed inboard from the pitch plate, a blade sleeve fixed to a blade and positioned in the pitch cylinder with a second face located with the first face, a blade slot extending inboard from the second face;
- rotating the blade sleeve until the blade slot is aligned with a first pitch slot of the pitch slots forming a first keyway corresponding to a first blade pitch;
- and
- fixing the blade at the first blade pitch by positioning a key in the first keyway.
Dependencies are inferred from the claim text.