초록 ▼

A helicopter rotor system with a plurality of identical rotor blades each of which includes a skin that forms an interior region, a counterweight rod and a bundle of longitudinally-extending fibers in the region. The bundle continues outside of the region, and there it includes a bight portion with

A helicopter rotor system with a plurality of identical rotor blades each of which includes a skin that forms an interior region, a counterweight rod and a bundle of longitudinally-extending fibers in the region. The bundle continues outside of the region, and there it includes a bight portion with a pair of arms and a bend. The fibers in the region are continuations of the fibers in the bight portion. A torque tube is attached to the counterweight rod, and a bearing stabilizes the torque tube relative to the mast, but does not transfer any appreciable centrifugal load. This bearing permits rotation (feathering) of the torque tube around its own axis, and lateral movement in any direction from the torque tube axis, around the center of this bearing (lead lag, and flapping). The bight portion is progressively shaped from a single flat portion bent directly around the mast, through a pair of separate channel sections to a bundle adjacent to the counterbalance rod. The fibers are bonded together, and in the said region they are bonded not only to each other, but also to the counterweight rod, and to the skin. The blades are angularly spaced apart, and their flat portions are stacked one on top of the other. Attachment means, preferably fasteners and mounting plates, attaches the stack of flat portions to the mast, where they transfer the centrifugal load to the mast and are driven directly by it.

대표청구항 ▼

A helicopter rotor system comprising: a rotary mast having an upright axis; a plurality of rotor blades mounted to said rotary mast to be turned by said mast, each said blade having a respective longitudinal axis directed away from said mast, all of said rotor blades being substantially identical to

A helicopter rotor system comprising: a rotary mast having an upright axis; a plurality of rotor blades mounted to said rotary mast to be turned by said mast, each said blade having a respective longitudinal axis directed away from said mast, all of said rotor blades being substantially identical to one another, and being angularly spaced apart around said mast, each said blade comprising a skin forming an airfoil and an internal region, a counterweight rod and a spar extending longitudinally inside said region, said spar comprising a bundle of aligned fibers which, inside said region are bonded to each other, to said skin, and to said counterweight rod, said bundle being doubled so as to form a U-shaped bight portion with a bend and a pair of arms disposed inboard of said skin, said fibers inside said region constituting continuations of the fibers in said arms; a longitudinally-extending torque tube rigidly attached to said counterweight rod at a first end of said torque tube, and a first bearing member adjacent to the other end of said torque tube, said torque tube having an axis; a second bearing member mounted to said mast and engaged to said first bearing member, whereby said torque tube is rotatable around its own axis, and can move in any angular direction away from said longitudinal axis around the center of said second bearing means, whereby to enable lead/lag and flapping movements; the bight portion being progressively shaped from a flat portion bent directly around said mast, through a pair of separate channel sections, to a bundle adjacent to said counterweight rod; pitch horn means attached to said torque tube to rotate said torque around the axis of said torque tube; attachment means attaching said flat portions of said bight portion in a stack to transfer centrifugal loads to said mast; and said bight portion being bendable adjacent to said mast.