Sikorsky Aircraft Corporation

United Technologies Corporation

Frank Paul D'Anna

David A Darrow, Jr

Stephen V Poulin

David N Schmaling

Bryan Kenneth Baskin

Frederick J Miner

Leonard J Doolin

Thomas L Sbabo

Lance Halcom

Michael R Robbins

Francis E Byrnes

David H Hunter

Mark R Alber

Fabio Paolo Bertolotti

Robert D Higbie

Kevin A White

Richard Thomas Hood

David A Darrow

Ryan Smith

Anthony V Russo

A rotor system of a tail-sitter aerial vehicle configured to rotate about an axis of rotation is provided including a rotor hub which rotates about the axis of rotation and at least one rotor blade operably coupled to the rotor hub. The at least one rotor blade is configured to rotate about a folding axis between an extended position where the at least one rotor blade is substantially within a plane perpendicular to the axis of rotation and a stowed position where the rotor blade is arranged out of the plane of at an angle less than ninety degrees to the axis of rotation.

Blade fold system using flap hinge

A rotor assembly includes a rotor hub which rotates about a hub rotation axis and a blade connected to the rotor hub. The blade rotates with the rotor hub around the hub rotation axis, and the blade is configured to rotate around a pitch rotation axis of the blade to adjust a pitch of the blade. The rotor assembly includes a pitch horn having a first end rotatably connected to the blade. The pitch horn is configured to rotate with the blade around the pitch rotation axis of the blade to adjust the pitch of the blade, and the pitch horn is configured to rotate relative to the blade around a pitch horn pivot axis arranged at a non-parallel angle relative to the pitch rotation axis of the blade.

Rotor blade pitch horn assembly

A box frame hub arm structure is provided and includes a body having an outboard surface, which is disposable to abut with an inboard surface of an outboard arm of an aircraft rotor head, and lead/lag sides. The body is formed to define a first cavity, an aperture communicative with the first cavity through the outboard surface and second and third cavities. The second and third cavities extend outwardly in opposite lead/lag directions from the first cavity to the lead/lag sides.

Rigid rotor head with tension torsion (TT) strap retention

An attachment assembly for coupling a rotary blade to a hub includes a hollow shear pin, a nut cap, and a tensioning fastener. The hollow shear pin defines an attachment axis. The nut cap abuts the shear pin along the attachment axis. The tensioning fastener is seated within the shear pin, is threadably engaged to the nut cap, and has an axial length that is smaller than an axial length of the shear pin to fix a rotary blade to a rotor assembly within a profile of the rotary blade.

Rotorcraft rotor assemblies

A rotor blade configured to fold about a blade fold axis includes a first section and a second section. The first section is configured to mount to a rotor hub and includes a first connector having at least one first opening. The second section includes a second connector having at least one second opening. The second section is rotatably coupled to the first section and is configured to rotate about the blade fold axis between an aligned position and a rotated position. A linkage is operably coupled to the first section and the second section. The linkage includes a plurality of links loosely connected such that the linkage is configured to support the second section of the rotor blade only when the second section is in the rotated position.

Non-loaded manual blade fold assembly

An aircraft is provided and includes an airframe, a blade disk, which is rotatable relative to the airframe, including a plurality of rotor blades, a rotor shaft disposed to drive rotation of the blade disk relative to the airframe and a pitching of each of the rotor blades about corresponding pitch axes and a rotor assembly configured to form couplings by which each of the rotor blades is coupled to the rotor shaft. The rotor assembly includes a composite laminate arranged to resolve loading associated with the couplings in-plane of the composite laminate.

Aircraft rotor assembly with composite laminate

A pin configured for use in a rotor blade movable between an aligned position and a folded position and having a rotor blade airfoil contour is provided including a cylindrical body configured to couple a first section and a second section of the rotor blade when the rotor blade is in the aligned position. A handle is mounted to an end of the cylindrical body and has an airfoil contour complementary to the rotor blade airfoil contour. The handle is movable between an open position and a closed position. When the handle is in the closed position, the handle is flush with an adjacent portion of the rotor blade. When the handle is in the open position, the handle is accessible to pull the cylindrical body from the first and second section s of the rotor blade.

A swashplate apparatus is provided and includes a first swashplate including outer and inner bodies and an intermediate portion defining a major groove between the outer and inner bodies, a second swashplate disposable in the major groove to be rotatable relative to the first swashplate, the second swashplate including an interior facing surface radially separated from the inner body to define a minor groove and defining a recess in which the rod end is disposable, a connector disposable in the recess to pivotably couple the rod end to the second swashplate and a plate element disposable in the minor groove and affixable to the interior facing surface of the second swashplate and the connector.

Swashplate apparatus

An aircraft rotor head is provided and includes a rotor hub including a central portion and radial arms extending outwardly from the central portion, blade retention yokes, each blade retention yoke being pivotably coupled to a corresponding one of the radial arms at one end and to a corresponding blade at another end and a lag restraint star rotatable about and translatable along the central portion. The lag restraint star is coupled to each of the blade retention yokes to facilitate uniform blade lead/lag and uniform blade coning.

Stiff inplane elastomeric rotorhead

A constant velocity drive includes a drive ring and a driven ring positioned around the drive ring. Drive links extend from the drive ring to the driven ring to transfer torque applied at the drive ring to the driven ring. Elastomeric bearings are positioned at the driven ring to transfer torque from a drive link of the plurality of drive links to the driven ring. Each elastomeric bearing includes both spherical bearing elements and planar bearing elements to allow for tilt of an axis of rotation of the driven ring with respect to an axis of rotation of the drive ring while ensuring a constant rotational velocity of the driven ring with respect to the rotational velocity of the drive ring.

Constant velocity drive for tilt rotor assembly

A rotor assembly includes a rotor hub rotatable about a central axis including a plurality of rotor hub arms and blade yokes, each blade yoke including yoke arms located at opposing lateral sides of a corresponding one of the rotor hub arms to which the rotor hub arm is operably connected. The rotor assembly further includes blade retention bearings, each blade retention bearing being a single-element bearing disposed at a corresponding one of the rotor hub arms and which is supportive of a corresponding one of the blade yokes. Rotor blades are secured to corresponding ones of the blade yokes.

Low drag rotor system

A control link disposed to transfer rotor shaft rotation from an elongate element rotatable with a shaft to a rotatable element is provided and includes a structure terminating at a first end thereof as a mating element, which is securable to the elongate element such that the elongate element is rotatable about an axis defined through the mating element and such that a moment reaction in opposition to structure rotation about the elongate element is generated and a rod coupled to the rotatable element being and configured to be coupled to a second end of the structure at variable distances relative to the rotatable element.

Adjustable scissor control link

A rotor assembly includes a rotor shaft rotatable about a rotor axis and a plurality of rotor blades operably connected to the rotor shaft. A rotor control assembly has a plurality of substantially concentric control tubes extending through the rotor shaft. Each control tube of the plurality of control tubes is operably connected to a rotor blade of the plurality of rotor blades such that movement of one or more of the control tubes of the plurality of control tubes along the rotor axis effects a pitch change in one or more rotor blades of the plurality of rotor blades. A method of controlling pitch of a plurality of rotor blades of a rotor assembly includes locating a plurality of concentric control tubes inside of a rotor shaft of the rotor assembly capable of changing a pitch of one or more of the rotor blades.

Control system and method for rotor assembly

A swash plate assembly includes a rotationally stationary swash plate and rotational swash plate which rotates relative to the rotationally stationary swash plate through a bearing system. Each servo control rod is attached to the swash plate assembly to communicate control inputs thereto through a respective servo lug. Each servo lug defines a servo pivot point off an in-line plane inboard of the bearing system. As the servo lugs extend below the rotationally stationary swash plate, a relatively uncomplicated attachment arrangement is facilitated which provides for redundant locking features at a highly inspectable location which simplifies maintenance and increased safety. By locating the servo pivot point just inboard of the bearing system, an exceeding compact load path is defined thereby. The load path is defined from the servo control, to the servo lug, through the rotationally stationary swash plate, bearing system, the rotational swash plate, the rotor pitch control point and into the pitch control rod.

Compact load path swashplate assembly

A rotor assembly having a rotor hub, a plurality of yokes, and a plurality of swing arms is provided. The yoke depending from the rotor hub. Each swing arm is movably positioned on the rotor hub for rotation between an unlocked position and a locked position. The yokes are freely movable about a pitch axis and a lead/lag axis when the swing arms are in the unlocked position and the yokes are locked in a predetermined pitch position and a predetermined lead/lag position when the swing arms are in the locked position.

Growing community of inventors

Seymour, CT, United States of America

Frank Paul D'Anna