초록 ▼

The present invention relates to an improved helicopter rotor system including a contoured flexure strap having a simplified geometrical configuration. The flexure strap serves to join the rotary hub assembly with the rotor blades and is formed of fiberglass. The primary load carrying fibers of the

The present invention relates to an improved helicopter rotor system including a contoured flexure strap having a simplified geometrical configuration. The flexure strap serves to join the rotary hub assembly with the rotor blades and is formed of fiberglass. The primary load carrying fibers of the flexure strap preferably extend in the same direction as the spanwise axis of the flexure strap in order to withstand the centrifugal forces acting on the strap. The inboard end portion of the flexure strap includes two separate ends, with one of the ends extending in a vertically upward direction and the other end in a vertically downward direction. This allows the ends of flexure straps positioned on opposite sides of the rotary hub assembly to overlap one another and be retained in place by a single pin and bolt assembly. A cloth wrap of composite matrix material surrounds portions of the flexure strap to provide redundancy which prevents the fibers in the flexure strap from delamination when subjected to forces arising during operation of the helicopter.

대표청구항 ▼

[ What is claimed is:] [1.] A flexure strap for joining a helicopter rotor blade to a helicopter rotary hub assembly, even when the blades are subjected to centrifugal forces and blade feathering, comprising:a strap member having an inboard end portion connected to the rotary hub assembly, an outboa

[ What is claimed is:] [1.] A flexure strap for joining a helicopter rotor blade to a helicopter rotary hub assembly, even when the blades are subjected to centrifugal forces and blade feathering, comprising:a strap member having an inboard end portion connected to the rotary hub assembly, an outboard end portion connected to the rotor blade, and an elongated mid portion extending between and joining the inboard and outboard end portions, the flexure strap being formed of a composite matrix material having a first group of fibers which extend parallel to the spanwise axis of the strap member and having a second group of fibers which extend at an angle to the spanwise axis of the strap member; andmeans mounted on the flexure strap for preventing delamination of the fibers as the strap member is subjected to centrifugal forces and cyclic motions during operation of the helicopter.