US 5,022,824 A · Pinned airfoil propeller blade

Abstract

An essentially composite propeller or fan blade is provided which is rotatably mounted to a blade retention pitch member by a pin radially outside of a propeller spinner or hub. The blade has a plurality of composite layers wrapped directly around a root fairing which engages the pin. The propeller blade has a motion limiter provided at the base thereof which cooperates with the blade retention pitch member to damp rotational movement of the blade about the pin to minimize blade angular excursions when centrifugal loads are low, to moderate blade vibratory motion, to help tune out undesirable blade resonant frequencies and to transmit force created by impact with foreign objects to the pitch member. By cooperating with the pitch retention member, the root of the blade may be more aerodynamically shaped than other composite blades which must absorb the force of impact in their root portions.

Claims15

Dependent claims

A high speed airfoil blade comprising:

a spar forming a main structural member of the said blade, said spar comprising:
a root portion, said root portion having;
means for allowing rotation of said blade about an axis passing through said blade in a chordwise direction, and
a composite insert attaching to said root portion, said insert extending along a length of said blade, said insert forming a main load bearing structure of said spar;
and,
a shell covering said root portion and said insert of said spar, said shell forming an airfoil surface.

3 more elements

Dependencies are inferred from the claim text.

Pinned airfoil propeller blade

Life of this patent

Pinned airfoil propeller blade

Life of this patent

Abstract

Claims15