Helicopter rotor assembly and blade pitch control

摘要

A helicopter including a driven rotor assembly provided with a hub having oscillatable rotor blades extending outwardly therefrom and axially spaced portions of the hub having outer peripheral portions of a pair of annular flexible and elastic supporting diaphragms anchored relative thereto. Inner peripheral portions of the diaphragms are deflected and stretched toward each other and anchored to a supporting flange carried by a central rotary drive shaft of the rotor assembly. A sleeve is longitudinally shiftably mounted on the shaft below the rotor assembly and supports, through the utilization of a flexible and resilient diaphragm, a larger sleeve structure therefrom for universal angular displacement of the sleeve structure relative to the sleeve. The sleeve structure includes control arms operatively connected to the rotor blades for oscillation of the latter in response to axial shifting of the sleeve structure relative to the sleeve. First control structure is provided for axially shifting the sleeve on the drive shaft and second control structure is provided for universally angularly displacing the sleeve structure relative to the sleeve. The helicopter further includes a third diaphragm supported control structure whose diaphragm is flexed in opposition to the flexed diaphragm of the second control structure and is manually universally shiftable and operatively connected to the second control structure for similar universal displacement thereof.