Patent application number | Description | Published |
20080247876 | Soft In-Plane Tiltrotor Hub - A rotor hub assembly for a rotary-wing aircraft has a central member and a plurality of blade grips adapted for attaching rotor blades to the central member. The blade grips are pivotally attached to the central member and are capable of pivoting about a pivot axis generally normal to a plane of rotation of the blades. The pivoting allows for in-plane motion of the blades relative to the central member. A damper is operably connected to each blade grip for damping the in-plane motion of the associated blade, each damper being selectively switchable between at least two spring rates. | 10-09-2008 |
20080267778 | Torque Coupling for Rotary-Wing Aircraft - A torque coupling ( | 10-30-2008 |
20080292468 | Stiff-in-Plane Gimbaled Tiltrotor Hub - A rotor-hub for a rotary-wing aircraft is disclosed. The rotor-hub comprises a yoke comprising a plurality of yoke arms and a plurality of yoke straps, wherein the yoke arms are joined together by the yoke straps, and wherein a plurality of inner walls of the yoke define a central void space. A pitch horn is movably connected to the yoke and a portion of the pitch horn is located within the central void space. A connecting shell is fixedly attached to the yoke. | 11-27-2008 |
20090179107 | Yoke with Notched Arm Roots - A yoke for a rotary wing aircraft rotor system has a plurality of arms, each arm having a root. Each root has a notched portion configured to allow passage of a portion of a blade-pitch control system through the notched portion. | 07-16-2009 |
20090325718 | Constant Velocity Joint for Tiltrotor Hubs - A constant-velocity joint is configured for use with a rotary-wing aircraft having at least one engine. A driver is coupled to an output shaft of the engine, the driver being rotatable about an axis. A yoke is at least partially rotatable relative to the driver about a first center of rotation, the center of rotation being located on the axis. A plurality of upright links couple the yoke to the driver, each link being translatable relative to the yoke, the driver, or both. Each link is also rotatable relative to the yoke, the driver, or both, about a second center of rotation. | 12-31-2009 |
20100009764 | Rotary-Wing Aircraft Torque Coupling with Pad Bearings - A torque coupling for a rotor head of a rotary-wing aircraft is configured for rotation with a mast and for causing rotation of an attached yoke. The coupling has trunnions that rotate with the mast and extend generally radially. Pad-bearing assemblies each have a central member coupled to one of the trunnions with a laminated spherical bearing and have laminated pad bearings affixed to opposing sides of the central member. The laminated bearings have alternating rigid and elastomeric layers. A bearing mount is affixed to each pad bearing and is connected to a yoke for rotating the yoke with the mast. The pad-bearing assemblies allow for relative motion between each central member and the associated trunnion and between each central member and the bearing mounts through elastic shear deformation, and this allows for gimballing of the attached yoke relative to the mast. | 01-14-2010 |
20100021301 | Step-Over Blade-Pitch Control System - A pitch control system for blades on a rotor of an aircraft has a gimballing rotor hub ( | 01-28-2010 |
20100090055 | Vibration-Attenuating Hard-Mounted Pylon - A preferred embodiment of a pylon has six pylon mounting links for mounting the pylon to an airframe. Each link is considered “near-rigid” and has a spherical-bearing rod-end on both ends such that the link can only transmit axial loads. At least one of the links has a mass carried within the link and selectively moveable by an actuating means along the axis of the link in an oscillatory manner for attenuating vibrations traveling axially through the link. The actuating means may be an electromechanical, hydraulic, pneumatic, or piezoelectric system. By mounting each link in a selected orientation relative to the other links, the actuating means may be operated in a manner that attenuates axial vibration that would otherwise be transmitted through the link and into the airframe. | 04-15-2010 |
20100209242 | Rotor Hub Vibration Attenuator - A vibration attenuator for an aircraft has at least one weight mounted in a rotating system of a rotor hub of the aircraft, each weight being rotatable about an axis of rotation of the hub relative to the hub and to each other weight. Drive means are provided for rotating each weight about the axis of rotation at a selected speed for creating oscillatory shear forces that oppose and attenuate rotor-induced vibrations having a selected frequency. | 08-19-2010 |
20100230529 | CF BEARING WITH STEADY PITCHING MOMENT - A centrifugal force bearing having a means for providing a steady pitching moment is disclosed. The centrifugal force bearing may optionally comprise a coning means. A rotor system having the centrifugal force bearing is disclosed. A rotary-wing aircraft having the centrifugal force bearing is disclosed. | 09-16-2010 |
20100266411 | Constant-Velocity Joint with Torque-Combining Differential - A constant-velocity drive system for an aircraft rotor has a gimbal mechanism and a differential torque-combining mechanism. The gimbal mechanism has gimbals driven in rotation by a rotor mast about a mast axis, the gimbals providing for gimballing relative to the mast about gimbal axes generally perpendicular to the mast axis. The differential torque-combining mechanism is connected to the gimbal mechanism and configured to be driven in rotation about the mast axis by the gimbal mechanism. The differential mechanism is capable of gimballing relative to the mast about the gimbal axes, the differential torque-combining mechanism having an output component attached to a yoke of the rotor for driving the yoke in rotation with the differential torque-combining mechanism. | 10-21-2010 |
20100301160 | Method and Apparatus for Improved Vibration Isolation - A vibration isolator is disclosed having a housing which defines a fluid chamber. A piston, which is movable to and from a down position, is disposed within the housing. A vibration isolation fluid is disposed within the fluid chamber. A passage having a predetermined diameter extends through the piston to permit the vibration isolation fluid to flow from one fluid chamber to the other. An elastic element is provided for reducing transmission of vibrations from the piston to the housing when the piston is at the down position. | 12-02-2010 |
20100314492 | Multiple Drive-Path Transmission with Torque-Splitting Differential Mechanism - A transmission for a rotary-wing aircraft has a differential torque-splitting mechanism associated with an input shaft. The differential has a drive disk coaxial with the shaft and integral in rotation with the shaft, a first driven member coaxial with the shaft and generally adjacent the drive disk, and a second driven member coaxial with the shaft and generally adjacent the drive disk. At least one pin engages each of the drive disk, the first driven member, and the second driven member. The first driven member is configured to drive a first transfer gear, and the second driven member is configured to drive a second transfer gear for supplying torque to a bull gear associated with a rotor mast. | 12-16-2010 |
20110027083 | Lead-Lag Damper for Rotor Hubs - A lead-lag damper for a rotor assembly has a body mounted to either an inboard portion of a blade assembly or a fixed portion of the rotor assembly. A piston carried within the body is configured to allow for relative motion between the body and the piston. The piston defines opposing chambers within the body, the chambers being in fluid communication through a fluid passage. A link connects the piston to the other of the inboard portion of the blade assembly and the fixed portion of the rotor assembly, and the link engages a central portion of the piston. The piston acts on fluid in the chambers during relative motion between the piston and the body and causes fluid flow between the chambers through the fluid passage. Flow through the passage acts to damp lead-lag motion of the blade assembly relative to the fixed portion of the rotor assembly. | 02-03-2011 |
20110194934 | Rotor Hub Vibration Attenuator - A vibration attenuator for an aircraft has at least one weight mounted in a rotating system of a rotor hub of the aircraft, each weight being rotatable about an axis of rotation of the hub relative to the hub and to each other weight. Drive means are provided for rotating each weight about the axis of rotation at a selected speed for creating oscillatory shear forces that oppose and attenuate rotor-induced vibrations having a selected frequency. A vertically oriented vibration attenuator is configured to oppose and attenuate vertical rotor induced oscillatory forces that would otherwise travel vertical down the rotor mast and into the airframe. | 08-11-2011 |
20110259687 | Method and Apparatus for Improved Vibration Isolation - A tunable vibration isolator having a housing, fluid chamber, and at least one tuning passage. A piston assembly is resiliently disposed within the housing. A vibration isolation fluid is allowed to flow from the fluid chambers through the tuning passage. A metering valve is actuated up and down in order to change the effective diameter of the tuning passage, resulting in a change to the isolation frequency. | 10-27-2011 |
20110274548 | Stiff-in-Plane Rotor Configuration - A rotor assembly for a rotary-wing aircraft, the rotor having a central hub assembly with a flexure-type, twist-shank yoke with multiple arms, each arm being adapted for a rotor blade to be mounted thereto. The arms provide for pitch changes of blades attached to the yoke through twisting of portions of the arms about a corresponding pitch axis. An inboard pitch bearing associated with each arm is attached to the hub assembly and allows for rotation of the attached blade about the pitch axis, the inboard pitch bearing also allowing for out-of-plane motion of the arm relative to the hub assembly about a flapping axis. An outboard pitch bearing associated with each arm is attached to the associated arm a selected distance from the inboard pitch bearing and allows for rotation of the attached blade about the pitch axis. | 11-10-2011 |
20110274550 | Yoke and Bearing Fitting Assembly for Rotors - A yoke and bearing fitting assembly for a multi-blade aircraft rotor is disclosed. The assembly has a yoke having arms extending generally radially from a central portion of the yoke, the arms each having opposing surfaces. An aperture is formed in each arm and extends between the surfaces. A bearing fitting has a body configured for insertion into the aperture of the yoke and has two rims protruding from a periphery of the body, the body also having a bearing mount adapted for mounting a pitch change bearing assembly to the yoke. Each rim abuts one of the surfaces of the associated yoke arm when the bearing fitting is installed within the aperture, so as to create clamping forces between the rims and the arm and the arm. The bearing fitting transmits forces from the pitch bearing assembly into the yoke. | 11-10-2011 |
20110280727 | Improved Rotor-Blade Control System and Method - A blade-pitch control system has a swashplate configured for continuous rotation with an associated rotor and mast, and at least one link connects the swashplate to each blade of the rotor. The swashplate provides for collective control of the pitch angle of the blades through selective rotation of the swashplate about a swashplate axis while the swashplate is rotating with the rotor and mast. The system can be configured to provide for cyclic control of the pitch angle of the blades through planar translation of the swashplate or through tilting of the swashplate about axes generally perpendicular to the swashplate axis. | 11-17-2011 |
20110315816 | Constant-Velocity Joint with Torque-Combining Differential - A constant-velocity drive system for an aircraft rotor has a gimbal mechanism and a differential torque-combining mechanism. The gimbal mechanism has gimbals driven in rotation by a rotor mast about a mast axis, the gimbals providing for gimballing relative to the mast about gimbal axes generally perpendicular to the mast axis. The differential torque-combining mechanism is connected to the gimbal mechanism and configured to be driven in rotation about the mast axis by the gimbal mechanism. The differential mechanism is capable of gimballing relative to the mast about the gimbal axes, the differential torque-combining mechanism having an output component attached to a yoke of the rotor for driving the yoke in rotation with the differential torque-combining mechanism. | 12-29-2011 |
20110315827 | Wing Extension Control Surface - A tiltrotor aircraft includes a rotatable nacelle that supports a rotor assembly and is pivotally attached to the air-craft's fuselage. A wing extension attaches to an outboard section of the nacelle. The wing extension provides additional yaw control during helicopter mode and additional lift during airplane mode. A method for controlling at least a portion of yaw movement includes positioning the rotor assembly in helicopter mode, creating rotor wash with the rotor assembly, and pivotally rotating the wing extension in the rotor wash. | 12-29-2011 |
20110316207 | Method and Apparatus for Improved Vibration Isolation - A vibration isolator having a housing defining a fluid chamber, piston assembly, tuning passage, and a switchable fluid path assembly for changing the isolation frequency of the vibration isolator. The piston assembly is resiliently disposed within the housing. A vibration tuning fluid is allowed to flow within the housing. Actuation of a valve in the switchable fluid path assembly selectively controls fluid flow within the fluid path of the switchable fluid path assembly. | 12-29-2011 |
20120180597 | Multiple Drive-Path Transmission with Torque-Splitting Differential Mechanism - A transmission for a rotary-wing aircraft has a differential torque-splitting mechanism associated with an input shaft. The differential has a drive disk coaxial with the shaft and integral in rotation with the shaft, a first driven member coaxial with the shaft and generally adjacent the drive disk, and a second driven member coaxial with the shaft and generally adjacent the drive disk. At least one pin engages each of the drive disk, the first driven member, and the second driven member. The first driven member is configured to drive a first transfer gear, and the second driven member is configured to drive a second transfer gear for supplying torque to a bull gear associated with a rotor mast. | 07-19-2012 |
20120201683 | Rotor Yoke and Method of Making the Same - A method of making a composite rotor yoke includes preparing a molded rotor yoke in a closed cavity tool and possibly machining at least one portion of the molded rotor yoke to form the rotor yoke. In the preferred embodiment, preparing the molded rotor yoke is accomplished by applying layers of uncured low-flow composite material and a layer of uncured high-flow adhesive; substantially enclosing the uncured molded rotor yoke in the closed cavity tool; applying pressure so as to compress the uncured molded rotor yoke; and curing the uncured molded rotor yoke. During the curing process, the high-flow adhesive bleeds out of the molded rotor yoke, thereby preventing marcels from forming through movement of the low-flow composite material. | 08-09-2012 |
20120230823 | Dual Spring Rate Damper - A rotor hub and method to dampen a force exerted on a rotor hub by a rotor blade during flight. The rotor hub including a central member rotatably coupled to a rotor mast, a blade grip rigidly attached to a blade and movably coupled to the central member, and an adjustable damper operably associated with the blade grip. The method includes damping the force exerted on the rotor hub with the adjustable damper and selectively adjusting the adjustable damper between a first spring rate and a second spring rate. | 09-13-2012 |
20120251225 | Self Pumping and Priming Adhesive Joint System - A tube form assembly includes an inner member and an outer member. Each of the inner and outer members has an offset which creates a cavity therebetween. During assembly of the tube form assembly, an adhesive is located in the cavity and squeezed out and through the adjacent bond lines between the inner member and outer member. The pressurization and flow of adhesive outward from the cavity facilitates removal of air bubbles, as well as prevents the introduction of air bubbles into the bond line. | 10-04-2012 |
20120279816 | Apparatus for Improved Vibration Isolation - A vibration isolator having an upper housing defining an upper fluid chamber, a lower housing defining a lower fluid chamber, a piston resiliently disposed within the upper housing and the lower housing, a tuning passage defined by the piston, for providing fluid communication between the upper fluid chamber and the lower fluid chamber, a tuning fluid disposed within the tuning passage, the upper fluid chamber, and the lower fluid chamber. A reservoir in fluid communication with the upper fluid chamber for providing pressurization control of the vibration isolator. An expanded accumulator region for providing Increased pressure retention during maintenance and operation of the vibration isolator. | 11-08-2012 |
20120292839 | Variable Stiffness Liquid Inertia Vibration Eliminator - A variable stiffness liquid inertia vibration isolation device includes a liquid inertia vibration elimination isolator and a variable stiffness spring operably associated with the liquid inertia vibration elimination isolator for varying the stiffness of the liquid inertia vibration isolator. The variable stiffness spring may include an elastomeric pad exhibiting a first stiffness along a first axis and a second stiffness, significantly greater than the first stiffness, along a second axis that is perpendicular to the first axis. | 11-22-2012 |
20120301299 | Composite Rotor Blade Having Weighted Material for Mass Balancing - A rotor blade for an aircraft includes a composite portion having fiber-reinforced resin material, the composite portion having an outside surface that forms at least a partial airfoil shape. The weighted portion includes a plurality of weighted material layers and a plurality of fiber-reinforced resin material layers. Weighted material is configured to be compatible with and integrated into composite manufacturing processes used to fabricate the rotor blade. The weighted portion has a higher density than the composite portion and positioned to produce desired mass balance characteristics of the rotor blade. | 11-29-2012 |
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 |
20130048127 | Temperature Adaptive Fluid Damping System - A temperature adaptive fluid damping system is provided. One embodiment of the temperature adaptive fluid damping system comprises two fluid chambers, a piston in fluid communication with the fluid chambers, and a fluid path between the fluid chambers. An elastomeric retaining element adjacent to the fluid path is constrained to deform substantially perpendicular to the fluid path, so that the retaining element is operable to vary the cross-sectional area of the fluid path inversely to a change in temperature. | 02-28-2013 |
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 |
20130084186 | ELASTOMERIC BEARING WITH TAPERED SHIMS - The centrifugal force bearing includes a plurality of tapered metal shims such that the thicker end of each tapered metal shim near the inner portion of bearing. The bearing can include a plurality of tapered elastomeric members that are consequently tapered so that the inner portions are narrower than the outer portions. The tapered metal shims can increase the axial stiffness in the direction of the centrifugal force, thereby reducing the axial deflection under loading, as compared to non-tapered shims. Further, reducing axial deflection reduces clearance issues that may arise when the rotor blade is allowed to axial deflect significant distances. As such, the tapered metal shims can increase the capacity of the bearing. Tapering the metal shims can decrease the compression induced shear strain near the outer portions of the elastomeric member, where loads are typically higher. | 04-04-2013 |
20130105621 | PYLON MOUNTING SYSTEM WITH VIBRATION ISOLATION | 05-02-2013 |
20130105637 | Active Prop Rotor Stability System | 05-02-2013 |
20130108447 | Increased Capacity Spherical Lined Bearings | 05-02-2013 |
20130119591 | Vibration Isolation System - A vibration isolator includes a housing having an upper fluid chamber, a lower fluid chamber, a piston, a tuning passage, and a linear inductance motor assembly for changing the isolation frequency of the vibration isolator. The piston is resiliently disposed within the housing. A vibration tuning fluid is located in the upper fluid chamber, the lower fluid chamber, and the tuning passage. The linear inductance motor assembly includes a magnet member and an inductance coil at least partially surrounding the magnet member. A control system is configured to selectively actuate the magnet member; wherein selective actuation of the magnet member selectively imparts a pumping force on the tuning fluid, thereby changing the isolation frequency. | 05-16-2013 |
20130121827 | Dual Mode Rotor Hub Assembly - A rotor hub assembly and method for controlling movement of a rotor blade relative to a swashplate. The hub assembly having an attachment device operably associated with the rotor blade and the swashplate. The attachment device provides pivot and rotational blade movement relative to the swashplate. A dual spring-rate damper is operably associated with the attachment device. The damper switches between a first spring rate and a second spring rate during flight to control movement of the rotor blade. The method includes the process of switching the damper between the first spring rate and the second spring rate during flight. | 05-16-2013 |
20130121828 | Rotor Hub Bearing System - The bearing system is configured for treating and reacting dynamic loading within a rotor hub of rotorcraft. The bearing system includes an outer member having a plurality of alternating outer elastomeric layers and shim layers. The outer member has an inboard surface configured for bonding to an inboard bearing support, and the outer member has an outboard surface configured for bonding to an outboard bearing support. The bearing system has an inner member bonded to an interior surface of the outer member. The inner member can include a rigid inner core, as well as a plurality of elastomeric layers and shim layers configured to react torsional movements of the rotor blade. | 05-16-2013 |
20130136596 | BLADE-PITCH CONTROL SYSTEM WITH FEEDBACK SWASHPLATE - A blade-pitch control system for controlling a pitch angle of blades on a rotor has an input swashplate assembly having non-rotating and rotating portions, the rotating portion being operably connected to blade grips. A feedback swashplate assembly has non-rotating and rotating portions, the rotating portion being connected to the yoke for movement with the yoke during flapping of the yoke. Linear actuators connect the non-rotating portion of the input swashplate assembly to the non-rotating portion of the feedback swashplate assembly. Motion of the yoke during flapping causes a corresponding motion of the feedback swashplate assembly and input swashplate assembly for providing selected pitch-flap coupling between flapping motion of the yoke and pitch motion of the grips. | 05-30-2013 |
20130149151 | Multiple-Yoke Main Rotor Assembly - The present application includes a main rotor assembly for an aircraft. The rotor assembly has a main rotor mast configured for rotation about a mast axis and two yokes pivotally connected to the mast for rotation therewith about the mast axis. Each yoke is independently pivotable relative to the mast about at least one flap axis that is generally perpendicular to the mast axis. In at least one embodiment, a torque splitter connects the yokes and allows for limited rotation of the yokes relative to each other about the mast axis. Each yoke is configured for the attachment of rotor blades extending generally radially relative to the mast axis. | 06-13-2013 |
20130156575 | Blade-Pitch Control System with Feedback Lever - The present application includes a blade-pitch control system for controlling a pitch angle of each of a plurality of blades on an aircraft rotor. A feedback lever associated with each blade is pivotally mounted to the rotating portion of a swashplate assembly. A pitch link connects an output arm of a lever to a pitch horn of a corresponding blade, and a feedback link connects the input arm of the lever to a yoke. Flapping motion of the yoke causes motion of the feedback link, and this motion causes corresponding rotation of the lever. Rotation of the lever causes motion of the pitch link, which changes the pitch angle of the attached blade. This provides for selected pitch-flap coupling between flapping motion of the yoke and pitch motion of the blades. | 06-20-2013 |
20130156580 | Constant-Velocity Drive System for Gimbaled Rotor Hubs - A constant-velocity drive system for a rotary-wing aircraft rotor comprising a differential torque-splitting mechanism and a gimbal mechanism is disclosed. A rotary-wing aircraft having a rotary-wing aircraft rotor comprising a differential torque-splitting mechanism and a gimbal mechanism is disclosed. | 06-20-2013 |
20130164129 | Hub Assembly with Grease Lubricated Roller Bearing and Tension-Torsion Strap - A rotary system and method to control feathering and centrifugal forces of a rotor blade during flight. The rotary system having a hub assembly, which includes a hollow yoke arm to receive a spindle section of the rotor blade. A tension-torsion strap extends through the hollow yoke arm and couples the rotor blade and the hub assembly. The method includes allowing the spindle section of the rotor blade to pivot within the hollow yoke arm and controlling rotational and centrifugal movement of the rotor blade with the tension-torsion strap. | 06-27-2013 |
20130168492 | Adjustable Pitch Link - 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. | 07-04-2013 |
20130175384 | Bearing Restraint for Rotor Systems - According to one embodiment, a rotor system comprises a yoke, a grip, an elastomeric bearing, and a bearing restraint. The grip is positioned around a portion of the yoke and has both a closed end and an open end. The elastomeric bearing is coupled to the closed end of the grip and located between the closed end and the yoke. The bearing restraint is coupled to the grip between the yoke and the open end at a distance from the closed end such that the yoke contacts the bearing restraint when the rotor system is subject to a first centrifugal force but does not contact the bearing restraint when the rotor system is subject to a second centrifugal force greater than the first centrifugal force | 07-11-2013 |
20130183508 | Attachable Elastomeric Pad - According to one embodiment, a method comprises calendering an elastomeric material into an elastomeric layer having a thickness that is more uniform than the elastomeric material prior to the calendaring. After calendaring, the elastomeric layer is vulcanized to a composite shim comprising at least one reinforcement layer and at least one layer of adhesive. | 07-18-2013 |
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 |
20130214087 | Coaxial Counter-Rotating Rotor System - A system and method to tilt coaxial counter-rotating rotor hub assemblies relative to a fuselage. The system includes a first rotor hub assembly and a second rotor hub assembly spaced apart from the first hub assembly and carried by the fuselage. The method includes pivotally attaching the first rotor hub assembly and the second rotor hub assembly to a pivot joint and thereafter tilting the first rotor hub assembly and the second rotor hub assembly about the pivot joint with a driver. | 08-22-2013 |
20130216382 | Hub Assembly with Centrifugal and Radial Bearings - A rotary system including a yoke having an opening forming a bridge for receiving a spoke extending therethrough. A rotor blade couples to the spoke and a pitch horn positioned outside the opening pitches the rotor blade during flight. A bearing assembly attaches the spoke and the pitch horn to the bridge and control blade forces exerted against the hub assembly during flight. | 08-22-2013 |
20130216384 | Compact Rotorcraft Dual-Element Spherical Elastomeric Centrifugal-Force Bearing Assembly - A rotary system includes a retention member and a flexible yoke having an opening forming a bridge. The rotary system is further provided with two bearing assemblies, a first bearing assembly extending through the opening of the yoke and configured to secure a rotor blade to the retention member and a second bearing assembly extending through the opening of the flexible yoke and configured to secure the rotor blade to the bridge. The second bearing element includes a bearing element having a first surface forming a spherical contouring and an opposing integral second surface forming a conical contouring. | 08-22-2013 |
20130216399 | ELASTOMERIC SIGNAL TRANSMISSION AND MOTION AMPLIFICATION - A system and method to amplify displacement includes a housing forming a cylindrical chamber having an elastomeric material disposed therein. The chamber being sealed with a first membrane and a second membrane. The first membrane being attached to a first end having and the second membrane being attached to a second end, the first end having a greater diameter than the second end. The method including producing an input displacement with a driver attached to the first membrane, which in turn results in an amplified output displacement at the second end. | 08-22-2013 |
20130224025 | Offset Stacked Yoke Hub for Tiltrotor Aircraft - A tiltrotor rotor hub comprises first and second configurations of yokes arranged in two parallel and axially offset planes, each having an equal number of two or more yokes substantially equally spaced about a mast, wherein a portion of each yoke overlaps with a portion of each azimuthally adjacent yoke. Another tiltrotor rotor hub is selectively positionable for operation in helicopter/airplane/transition modes and comprises substantially parallel and axially offset first and second planes, each containing a plurality of blade yokes arranged about a central axis and a portion of each yoke overlaps with a portion of each azimuthally adjacent yoke. Another tiltrotor rotor hub is coupled to a tiltrotor mast and comprises a stacked arrangement of blade yokes wherein a portion of each yoke overlaps with a portion of each azimuthally adjacent yoke, and a plurality of mounting components coupling each yoke to the overlapping azimuthally adjacent yoke. | 08-29-2013 |
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 |
20130274961 | Self Tuning Vibration Isolation System - A system and method to isolate vibrations from a vibrating structure. The system includes an adjustable vibration isolator that creates a reacting force matching the vibratory force of the vibrating structure. The method includes continuously monitoring the reacting force and vibratory force with a sensor system operably associated with a control unit having an algorithm to determine if adjustment of the vibration isolator is required. If required, the control unit commands a driver to selectively adjust the vibration isolator. | 10-17-2013 |
20130282204 | Self Tuning Vibration Absorber - A system and method to adjustably create a reacting force in response to a vibrating force of a vibrating structure. The system includes an adjustable vibration absorber that creates a range of reacting forces. The method includes continuously monitoring the reacting force and the vibrating force with a sensor system operably associated with a control unit having an algorithm to determine if adjustment of the vibration absorber is required. If required, the control unit commands a driver to selectively adjust the vibration absorber such that the reacting force equals the vibrating force. | 10-24-2013 |
20130287576 | Aircraft Rotor with Discrete Flap Hinge - An aircraft rotor assembly has upper and lower hub plates adapted to be mounted to a central rotor mast for rotation therewith. A plurality of radial arms is connected to at least two flap bearings mounted between the hub plates and forming a discrete flap hinge, each flap hinge defining a flap axis and allowing rotation of the associated arm relative to the hub plates and about the corresponding flap axis. Each of a plurality of blade grips is rotatably connected to one of the arms for rotation about a pitch axis and adapted for mounting of a blade to each blade grip, such that each blade is capable of rotation with the grip about the pitch axis and capable of rotation together with the corresponding arm relative to the hub plates and about the corresponding flap axis. | 10-31-2013 |
20130306420 | PIEZOELECTRIC LIQUID INERTIA VIBRATION ELIMINATOR - 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. | 11-21-2013 |
20130341458 | HYBRID SPHERICAL AND THRUST BEARING - According to one embodiment, a bearing is situated between a pitch link and a swashplate or a hub. The bearing comprises an outer housing having a first opening therethrough, an elastomeric bearing adjacent the housing inside the first opening and having a second opening therethrough, and an inner housing adjacent the elastomeric bearing inside the second opening and having a third opening therethrough. The inner housing comprising a first inner surface and a second inner surface defining the third opening. A first member is adjacent the first inner surface inside the third opening having a fourth opening therethrough. A second member is adjacent the second inner surface inside the third opening having a fifth opening therethrough coaxial with the fourth opening. | 12-26-2013 |
20140064922 | System and Method for Vibration Isolation - In accordance with one embodiment of the present disclosure, a system includes a first housing, a second housing, a seal, and a spring system. The first housing includes a first volume of fluid. The first housing is capable of connecting to a first element and to a second element, and is also capable of reducing an amount of movement transferred from the first element to the second element. The second housing is connected to the first housing. The second housing includes a second volume of fluid and a volume of gas. The first volume of fluid is in fluid communication with the second volume of fluid. The seal is capable of separating the second volume of fluid from the volume of gas. The spring system is capable of applying pressure to the first volume of fluid and the second volume of fluid. | 03-06-2014 |
20140124615 | Preventing Rotation of a Fixed Ring of a Swashplate - According to one embodiment, a rotor system includes an anti-rotation sleeve featuring an outer recess portion and a tilt sleeve positioned about the anti-rotation sleeve and having an opening therethrough. A first swashplate ring is positioned about the tilt sleeve and features an inner recess portion. An anti-rotation mechanism is disposed through the opening and at least partially in the outer recess portion and the inner recess portion. The anti-rotation mechanism is operable to prevent the first swashplate ring from rotating about the anti-rotation sleeve. A second swashplate ring is positioned about the first swashplate ring and rotatable about the anti-rotation sleeve. | 05-08-2014 |
20140133979 | Constant Velocity Joint with Control Mechanism - According to one embodiment, a constant velocity (CV) joint includes a first yoke, a second yoke, and a control mechanism. 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 control mechanism is adapted to constrain the first yoke and the second yoke so as to achieve a substantially CV characteristic between the input device and the output device. | 05-15-2014 |
20140133980 | Blade-Pitch Control System with Indexing Swashplate - The present application includes a blade-pitch control system with an indexing swashplate. A swashplate assembly has a non-rotating portion and a rotating portion and an indexing portion of the mast. The swashplate assembly is translatably affixed to the indexing portion. A pitch link connects the rotating portion of the swashplate assembly to each blade. Translation of the swashplate assembly along the indexing portion causes a change in pitch of the blades and a corresponding indexing of the rotating portion of the swashplate assembly relative to the mast, the indexing causing a change in an angular orientation of each pitch link, thus providing for selected pitch-flap coupling between flapping motion of the yoke and pitch motion of the blades. | 05-15-2014 |
20140217659 | PNEUMATICALLY AUGMENTED ELASTOMERIC DAMPER FOR IMPROVED SPRING RATE TUNING - A system and method to change a spring rate of a damper in real time. The damper includes a housing having an inner surface that forms a cavity. An elastomeric material is disposed within the cavity and fixedly attached to the inner surface of the housing. A first chamber is formed by a first end of the elastomeric material and the inner surface of the housing. The method includes restricting movement of the elastomeric material by regulating the pressure within the first chamber, which in turn changes the spring rate of the damper. | 08-07-2014 |
20140241886 | Rotor System Shear Bearing - A shear bearing for a rotor system has a four bar linkage and a grip configured to retain a flexural yoke and the grip is connected between a first set of opposing links of the four bar linkage. A rotor system has a flexural yoke and a shear bearing configured to perform at least one of transmitting forces to the yoke and receiving forces from the yoke, wherein the yoke is free of cavities for receiving the shear bearing. A rotational system has a flexural yoke and a damper disposed on a surface of the yoke. | 08-28-2014 |
20140248011 | BEARING WITH A SHAPE MEMORY ALLOY COMPONENT - The bearing assembly includes one or more elastomeric members loaded in a precompression by a shim that includes a shape memory alloy. The shape memory alloy is configured to generate the precompression in the elastomeric members upon a temperature change. | 09-04-2014 |
20140248150 | Constant Velocity Joint with Spring Rate Control Mechanism - 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. | 09-04-2014 |
20140262645 | HYBRID FLUID ELASTOMERIC DAMPER - A damper includes a housing that forms a fluidly sealed cavity for receiving a fluid therein. The fluid is configured to change fluid properties as electrical energy is induced. An electrical subsystem provides electrical energy to the fluid, which is monitored with a control subsystem. The method includes inducing the fluid with electrical energy to change the dampening effects of the damper in real time. | 09-18-2014 |
20140270610 | Rotor Hub Elastomeric Bearings - An apparatus comprising a drivelink comprising a housing including a socket, wherein the socket comprises a cross-sectional area, and a bearing cartridge disposed within the socket, wherein a cross-sectional area of the cartridge is less than the cross-sectional area of the socket. An apparatus comprising a drivelink comprising a housing having a socket, and a bearing cartridge positioned within the socket and comprising a first portion and a second portion, wherein the first portion is configured to undergo compression when a load is applied to the drivelink, and wherein the second portion is configured to not be in tension when the load is applied to the drivelink. | 09-18-2014 |
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 |
20140271200 | Flexing Clevis Arrangement Bolted Joint Attachment For Flexible Rotor Hub With High Offset And High Flapping - 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. | 09-18-2014 |
20140271203 | Swashplateless Active Blade Pitch Control with a Mechanical Delta-3 Restraint Having an Instantaneous Blade Pitch-flap Coupling Response - An apparatus comprising a hub configured to couple to a mast, a grip configured to couple to the hub and a rotor blade, a pitch actuator coupled to the grip and configured to change a pitch of the rotor blade relative to the mast, and a delta-3 restraint coupled to the pitch actuator, wherein the delta-3 restraint is fixed relative to the mast. An apparatus comprising a hub configured to couple to a mast, a grip configured to couple to the hub and a rotor blade, a pitch actuator coupled to the grip and configured to change a pitch of the rotor blade relative to the mast, and a delta-3 restraint coupled to the pitch actuator, wherein the delta-3 restraint is configured to control the pitch of the blade relative to the mast when the pitch actuator fails, and wherein the delta-3 restraint provides an instantaneous blade pitch-flap coupling response. | 09-18-2014 |
20140271204 | Tiltrotor Control System With Two Rise/Fall Actuators - 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. | 09-18-2014 |
20140271223 | Spinner Fairing Assembly - An apparatus comprising a spinner fairing assembly comprising a spinner configured to be fixed relative to a gimbaled yoke coupled to a mast system, and a spinner base configured to be fixed relative to the mast system. A spinner fairing assembly comprising a spinner aligned along a first axis, and a spinner base aligned along a second axis and configured to interface with the spinner, wherein the spinner is configured to transition between a neutral position and a canted position with respect to the spinner base, wherein the first axis and the second axis are coincident in the neutral position, and wherein the first axis and the second axis are not coincident and meet at an origin within the spinner in the canted position. | 09-18-2014 |
20140274427 | Multilink Constant Velocity Joint - An apparatus comprising a rotor hub system comprising a floating plate, a plurality of drive link trunnions each comprising a pivoting arm and positioned radially about the floating plate, wherein each drive link trunnion is coupled to the floating plate via the pivoting arm, and a housing disposed about the floating plate, coupled to each of the drive link trunnions, and configured to couple to a mast. Included is an apparatus comprising a floating plate, a plurality of drive link trunnions each comprising a pivoting arm and positioned radially about the floating plate, wherein each drive link trunnion is coupled to the floating plate via the pivoting arm, and wherein the drive link trunnions are configured to move the floating plate in response to a force applied to the drive link trunnions, and a housing disposed about the floating plate and coupled to each of the drive link trunnions. | 09-18-2014 |
20140286772 | ROTOR HUB VIBRATION ATTENUATOR - A vibration attenuator for an aircraft has at least one weight mounted in a rotating system of a rotor hub of the aircraft, each weight being rotatable about an axis of rotation of the hub relative to the hub and to each other weight. Drive means are provided for rotating each weight about the axis of rotation at a selected speed for creating oscillatory shear forces that oppose and attenuate rotor-induced vibrations having a selected frequency. A vertically oriented vibration attenuator is configured to oppose and attenuate vertical rotor induced oscillatory forces that would otherwise travel vertical down the rotor mast and into the airframe. | 09-25-2014 |
20140305755 | ELASTOMERIC DAMPER WITH HEATER - A damper system includes a damper and a heater operably associated with the damper. The method includes heating the damper with heat energy from the heater and then monitoring and regulating the heat energy to the damper with a sensor and control subsystem. | 10-16-2014 |
20140322010 | CONSTANT-VELOCITY JOINT LINK WITH REDUCED AXIAL STIFFNESS - The present application provides a drive link for a constant-velocity joint of an aircraft rotor, the link connecting a drive hub attached to a driveshaft to a rotor yoke. The link comprises a leading bearing connected to the drive hub, a trailing bearing connected to the yoke, a central portion between the bearings, and a tension loop connecting the bearings. The tension loop is formed from a composite material and is formed as a continuous band. The tension loop transfers drive forces from the leading bearing to the trailing bearing for driving the yoke in rotation with the driveshaft. | 10-30-2014 |
20140328685 | Hybrid Sliding Element and Elastomeric Bearing - According to one embodiment, a bearing is situated in a rotor system. The bearing features a housing having a first opening therethrough, a first member disposed within the first opening and having a second opening therethrough, and an elastomeric bearing disposed within the second opening and having a third opening therethrough configured to receive a shaft. The first member having at least one substantially curved surface. A sliding element bearing disposed between the housing and the first member. | 11-06-2014 |
20140360830 | ROTOR HUB VIBRATION ATTENUATOR - A vibration attenuator for an aircraft has at least one weight mounted in a rotating system of a rotor hub of the aircraft, each weight being rotatable about an axis of rotation of the hub relative to the hub and to each other weight. Drive means are provided for rotating each weight about the axis of rotation at a selected speed for creating oscillatory shear forces that oppose and attenuate rotor-induced vibrations having a selected frequency. A vertically oriented vibration attenuator is configured to oppose and attenuate vertical rotor induced oscillatory forces that would otherwise travel vertical down the rotor mast and into the airframe. A vibration attenuator having weights rotating about separate axes offset from each other. | 12-11-2014 |
20150034772 | Composite Flexure for Tiltrotor Rotor System - 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. | 02-05-2015 |
20150060597 | Dual Series Pitch Link Bearing - According to one embodiment, a bearing is situated between a pitch link and a swashplate or a hub. The bearing comprises an outer housing having a first opening therethrough, an intermediate housing adjacent the housing inside the first opening and having a second opening therethrough, and an inner housing adjacent the intermediate housing inside the second opening and having a third opening therethrough. The inner housing comprising a first inner surface and a second inner surface defining the third opening. A first member is adjacent the first inner surface inside the third opening having a fourth opening therethrough. A second member is adjacent the second inner surface inside the third opening having a fifth opening therethrough coaxial with the fourth opening. | 03-05-2015 |