Bell Helicopter Textron Inc.

Textron Corporation

William D Neathery

Willem Broekhuizen

Ernst C Schellhase

Cecil E Covington

Troy M Gaffey

Mukund M Joglekar

Patrick R Tisdale

Madison K Robinson

Joseph J Zierer

Peter A Reyes

Jan M Drees

Robert W Metzger

Paul E Keefer

Larry W Dooley

By Peggy Anastas, Executrix

Martin H Lufkin

Dan Anastas, Deceased

A constant velocity joint (10) is provided specifically for connecting a yoke (14) to a mast (12) in a helicopter and more generally (200) for interconnecting a first shaft (202) to a second shaft (204) for bidirectional drive. The constant velocity joint employs a carrier (40, 218) which is formed with a series of apertures for receiving elastomeric bearing assemblies (42, 80, 220). The elastomeric bearing assemblies are provided with a spherical elastomeric bearing (60) and a cylindrical elastomeric bearing (48). Certain of the elastomeric bearing assemblies connect the carrier to one of the rotating members while the remaining elastomeric bearing assemblies connect the other rotating member to the carrier. The axis of symmetry (67) of the carrier always bisects the angle of misalignment between the two rotating shafts or members to assure that a constant velocity joint is achieved.

Constant velocity elastomeric joint

The system comprises a grip of composite material having belts, filament windings unidirectional material and fillers of off axis bias ply material for directing the CF exerted on the grip by the blade rotation to the clevis throat of the grip. The force is further directed through a CF fitting, a CF bearing and an OPCBA to the yoke, thereby maintaining the yoke in tension. Should this load path fail, the CF will be transmitted through the length of the grip to the IPCBA that will in turn load the yoke with the CF.

Rotor redundant force retention system for VTOL and VSTOL aircraft

Folding and folding locking apparatus for rotor blades that includes a power actuator for rotating the blades and locking means for securing the blade in the deployed position and securing the blades against rotation of the pitch angle during and when the blades are folded. The apparatus also provides for the complete fairing of the blades at their connections with the rotary drive hub and provides a powered door in the fairing that can be opened and closed to permit the quick and easy folding and redeployment of the blades.

Apparatus and method for folding and locking rotor blades

A constant velocity joint (200) for interconnecting a first shaft (202) to a second shaft (204) for bidirectional drive is provided. The constant velocity joint employs a carrier (218) which is formed with a series of apertures for receiving elastomeric bearing assemblies (220). The elastomeric bearing assemblies are provided with a spherical elastomeric bearing (60) and a cylindrical elastomeric bearing (48). Certain of the elastomeric bearing assemblies connect the carrier to one of the rotated members while the remaining elastomeric bearing assemblies connect the other rotating member to the carrier. The axis of symmetry of the carrier (218) will always bisect the angle of misalignment between the two rotating shafts to assure that a constant velocity joint is achieved.

Constant velocity elastomeric bearing joint

This invention relates to helicopter rotors and more particularly to rotor mounting involving a composite fiber-reinforced unitary yoke with resilient inplane restraints.

Soft inplane bearingless helicopter rotor

A system for opposing helicopter blade flapping applies restraining forces at a low spring rate at low flap angles and at a high spring rate at flap angles greater than a predetermined angle. More particularly, bearings rotatably support the blade yoke on rotor hub trunnions which form a flapping axis. A resilient mechanical coupling between the blade yokes and the hub trunnion applies a restraining force having a characteristic linear with flapping angle. A second restraint mounted to rotate about the flapping axis with the rotor, applies a nonlinear restraining force which preferably rapidly increases beginning at a predetermined flap angle, and over the range short of hard flapping contact between the rotor and the rotor mast.

Compound hub spring system for helicopters

A helicopter having a multiblade main rotor lift unit includes a plurality of pendulus mass units (48,60) mounted to oscillate in the plane of the rotor. The mass units (48,60) are connected to a rotatable shaft (24) which passes through a blade grip (14) for each blade (16). Vibrations generated in the plane of the rotor system are damped by the oscillating pendulums (22) which are tuned to minimize the vibrations in the lift unit.

Blade-mounted centrifugal pendulum

A helicopter having a main rotor lift unit includes a plurality of pendulus mass units (44, 46) mounted to oscillate in a plane perpendicular to the chord plane of the rotor blade (10). The mass units (44, 46) are connected to a rotatable shaft (28) which passes through or adjacent the blade grip (12) for each blade (10). Hubshear vibrations generated parallel to the axis of the rotor mast (18) are damped by the oscillating mass units (44, 46) which are tuned to minimize the vibrations transmitted from the lift unit to the fuselage.

Growing community of inventors

Fort Worth, TX, United States of America

William D Neathery