| Patent application number | Description | Published |
|---|
| 20130004311 | Rotor Hub for Use with High-Inertia Blades - A rotor hub has a yoke with radial arms allowing flapping of connected blades about a flap axis. A grip is rigidly attached to each blade, and a lead-lag bearing connects each grip to one of the arms, the bearing defining a lead-lag axis outboard of the flap axis. Each arm has a pair of straps located on opposite sides of the rotor plane for transferring centrifugal force from the blades to the central portion of the yoke. A pair of lead-lag dampers is provided for each grip, the dampers of each pair being located on opposite sides of the rotor plane and connecting an inboard end portion of the grip to the adjacent strap. In-plane motion of a blade causes rotation of the attached grip about the lead-lag axis, causing opposite motion of an inboard end portion of the grip. The dampers act to oppose rotation of the grip. | 01-03-2013 |
| 20130084183 | DUAL SERIES DAMPER SYSTEM - A dual series damper includes a fluid damper portion and a elastomeric damper portion. The fluid damper portion includes a first housing, a first connection member, and a piston coupled to the first connection member. The piston divides an interior of the first housing into a first fluid chamber and a second fluid chamber. The piston has a fluid passage in the piston, the fluid passage being configured to provide fluid communication between the first fluid chamber and the second fluid chamber. The elastomeric damper portion includes a second housing, a second connection member coupled to the second housing, and an elastomer between the first housing and the second housing. When a lead/lag force is introduced to the dual series damper, the fluid damper portion behaves rigidly so that the elastomeric damper portion dampens the lead/lag oscillation. | 04-04-2013 |
| 20130189098 | System and Method of Harvesting Power with a Rotor Hub Damper - The system and method of the present application relate to a lead/lag damper for a rotorcraft. The lead/lag damper is configured to harvest power from the lead/lag oscillatory motions of rotor blades with an electromagnetic linear motor/generator. Further, the lead/lag damper is configured to treat the lead/lag motions with the electromagnetic linear motor/generator. The system and method is well suited for use in the field of aircraft, in particular, helicopters and other rotary wing aircraft. | 07-25-2013 |
| 20130241124 | Dual Frequency Damper for an Aircraft - A dual frequency damper includes a liquid inertia vibration eliminator (LIVE) portion and a fluid damper portion. LIVE portion and fluid damper portion operate in series and function so that dual frequency damper is optimized in both stiffness and damping at multiple frequencies. LIVE portion acts as a frequency dependent switch to selectively cause low frequency oscillatory forces to be treated primarily by the high spring rate and high damping rate characteristics of the fluid damper portion, and also to select high frequency oscillatory forces to be primarily treated by the low spring rate and low damping rate characteristics of the LIVE unit portion. | 09-19-2013 |
| 20140271182 | SOFT IN-PLANE AND STIFF OUT-OF-PLANE ROTOR SYSTEM - A rotor assembly includes a yoke operably associated with a rotor blade. The yoke includes a first device and a second device that attach the rotor blade to the yoke. The first device is configured to allow transverse movement of the rotor blade about a chord axis and rotational movement about a pitch-change axis. The second device is configured to allow rotational movement of the rotor blade solely about the pitch-change axis. The method includes rotating rotor assembly about a first plane of rotation, while retaining a relatively stiff out-of-plane rotation and a relatively soft in-plane rotation during flight. | 09-18-2014 |
