초록 ▼

A propeller for aircraft has a tip-to-tip flex-beam spar and torsionally stiff hollow blades bonded to the spar throughout an outer portion of the blades. The spar has two end caps which are separated from each other at the hub and converge in the outer portion. The blades have an inner region which

A propeller for aircraft has a tip-to-tip flex-beam spar and torsionally stiff hollow blades bonded to the spar throughout an outer portion of the blades. The spar has two end caps which are separated from each other at the hub and converge in the outer portion. The blades have an inner region which is not bonded to the spar, allowing an inner portion of the spar to twist during pitch changes. A counterweight is mounted to an arm extending from an inner end cuff of each blade. The counterweight is located out of the plane of rotation. The counterweight is also located on a side of a line opposite from the trailing edge, the line passing through the pivot axis perpendicular to the plane of rotation.

대표청구항 ▼

[ What is claimed is:] [1.] An aircraft blade assembly, comprising:a hub adapted to be connected to a drive shaft for rotation therewith;a blade on each side of the hub and extending outward along a blade axis, each of the blades having a cuff adjacent to the hub and a tip, the blades when rotated b

[ What is claimed is:] [1.] An aircraft blade assembly, comprising:a hub adapted to be connected to a drive shaft for rotation therewith;a blade on each side of the hub and extending outward along a blade axis, each of the blades having a cuff adjacent to the hub and a tip, the blades when rotated by the hub defining a plane of rotation;a pitch horn mounted to each of the cuffs and adapted to be connected to a pilot controlled linkage for pivoting each of the blades relative to the hub about the blade axis for making pitch changes;a spar mounted to the hub and extending continuously from approximately one of the tips to approximately the other of the tips, the spar having two spar caps separated from each other in the plane of rotation at the hub; andeach of the blades being mounted to and enclosing the spar caps, wherein each blade has an inner portion extending outward from each of the cuffs that is hollow and free of engagement with the spar caps to enable twisting of an inner portion of the spar caps while each of the blades is pivoted about the blade axis during the pitch changes.