Abstract:
According to one embodiment, a rotor head includes a yoke, a torque-splitter assembly, and a joint assembly. The torque-splitter assembly includes a spine assembly, a first trunion, and a second trunion. The spline assembly is configured to receive the drive shaft through a first opening. The spline assembly has a first plurality of outer splines oriented in a first direction and a second plurality of outer splines oriented in a second direction different from the first direction. The first trunion is disposed about the first plurality of outer splines. The second trunion is disposed about the second plurality of outer splines.
Abstract:
According to one embodiment, a composite flexure may secure a rotor blade to a yoke in a tiltrotor rotor system. The composite flexure includes a composite body, a first end configured to couple the composite member to the yoke, and a second end configured to couple the composite member to the rotor blade.
Abstract:
A rotor system for rotor aircraft comprises a rotor hub comprising a plurality of rotor blades, a rotatable rotor mast coupled to the rotor hub, a swashplate assembly comprising a non-rotating ring engaged with a rotatable ring, a plurality of pitch links mechanically coupling the rotatable ring to the plurality of rotor blades, and a swashplate actuator system. The rotatable ring is configured to rotate with the rotor mast, and the non-rotating ring is configured to engage and guide the rotatable ring. The pitch links are configured to control the pitch angle of each rotor blade. The swashplate actuator system consists of: a first actuator and a second actuator, where the first actuator and the second actuator are mechanically coupled to a stationary surface and the non-rotating ring.
Abstract:
A flexible joint assembly for providing flexure to a rotor blade comprising an upper hub plate and a lower hub plate configured to secure a rotor blade yoke via a bolted joint located radially outward of a mast; and an upper flexure assembly connected to the upper hub plate and a lower flexure assembly connected to the lower hub plate, wherein the upper flexure assembly and lower flexure assembly are configured to promote flapping of the rotor blade yoke about a flapping hinge located radially outward of the bolted joint.
Abstract:
According to one embodiment, a constant velocity (CV) joint includes a first yoke, a second yoke, and three bearings. The first yoke is configured to be rotatably coupled to an input device about a first axis and configured to receive the input device through a first opening. The second yoke is rotatably coupled to the first yoke about a second axis and rotatably coupled to an output device about a third axis. The first bearing is disposed about the first axis adjacent to the first yoke, the second bearing is disposed about the second axis adjacent to the first yoke or the second yoke, and the third bearing disposed about the third axis adjacent to the second yoke. The first and third bearings torsionally constrain movement the first yoke and the second yoke so as to achieve a substantially CV characteristic between the input device and the output device.
Abstract:
A tunable vibration isolator with active tuning elements having a housing, fluid chamber, and at least one tuning port. A piston is resiliently disposed within the housing. A vibration isolation fluid is disposed within the fluid chambers and the tuning ports. The tunable vibration isolator may employ either a solid tuning mass approach or a liquid tuning mass approach. The active vibration elements are preferably solid-state actuators.
Abstract:
According to one embodiment, a pitch link includes a first link, a second link coupled to a first end of the first link, a third link coupled to a second end of the first link opposite the first end, and a first bearing housing having a first bearing and a second bearing housing having a second bearing. The first bearing housing is removably coupled to the second link. The second link separates the first bearing housing from the first link. The second bearing housing is removably coupled to the third link. The third link separates the second bearing housing from the first link.
Abstract:
A rotor blade system includes a hub assembly pivotally attached to a rotor blade, a mast attached to the hub assembly, and a swashplate engaged with the mast, the swashplate includes a non-rotating ring and a rotating ring. The method to raise the swashplate includes using an anti-drive link system pivotally engaged with a transmission top case and pivotally engaged with the non-rotating ring.
Abstract:
A drive coupling has first and second coaxial end adapters. A first set of at least two coaxial helical elements has a first end of each element attached to the first end adapter, and a second end of each element is coupled to the second end adapter. At least one biasing device biases the end adapters relative to each other. Torque applied to one of the end adapters is transferred through the first set of helical elements to the other end adapter, the helical elements allowing for misalignment of the end adapters during operation.
Abstract:
In one embodiment, an apparatus comprises a shaft, a rotor, and a cam surface. The shaft comprises a spiral spline along a length of the shaft. The rotor comprises a blade extending from the rotor and a tubular hole extending into the rotor. The tubular hole comprises a spiral groove configured to mate with the spiral spline on the shaft. Relative rotation between the spiral spline and the spiral groove causes the rotor to linearly move along the shaft. The cam surface comprising a recession. The blade nesting in the recession to constrains rotation of the rotor about the shaft and allows linear movement of the rotor along the shaft.