Variable camber airfoil

Claim 2

A variable camber airfoil comprising: an upper surface; a contractable lower surface; a pair of canted hinges spaced chordwise and supported from the upper surface; a pair of truss members each pivotally mounted about one end on a canted hinge and having a pivotal interconnection at their other end; and actuating means for rotating the truss members about their canted hinges to bend the upper surface and contract the lower surface and thereby increase the camber of the airfoil.

Claim 3

The variable camber airfoil as set forth in claim 1, further including a stiffener channel extending spanwise between the pair of canted hinges; said contractable lower surface having an overlapping slip-joint; said stiffener channel having a closed end attached to the upper surface and having its open end extending therefrom to support the overlapping slip-joint of the lower surface; and said stiffener being designed to open and close in spring-like fashion as the degree of overlap changes due to airfoil camber variations.

Claim 4

A variable camber airfoil comprising: an upper surface; a contractable lower surface; a pair of parallel beams supported spanwise from the upper surface; a pair of canted hinges each mounted to one of said beams in chordwise alignment; a pair of truss members each pivotally mounted about one end on a canted hinge and having a pivotal interconnection at their other end; and actuating means for rotating the truss members about their canted hinges to bend the upper surface and contract the lower surface and thereby increase the camber of the airfoil.

Claim 5

A variable camber airfoil comprising: an upper surface; a contractable lower surface; a pair of parallel beams supported spanwise from the upper surface; a pair of canted hinges each mounted to one of said beams in chordwise alignment; a pair of truss members each pivotally mounted about one end on a canted hinge and having a pivotal interconnection at their other end; and actuating means for rotating the truss members about their canted hinges to bend the upper surface and contract the lower surface and thereby increase the camber of the airfoil.

Claim 6

A variable camber airfoil comprising: an upper surface; a contractable lower surface; a pair of parallel beams extending from the upper surface to the lower surface, being rigidly attached to the upper surface in a spanwise direction and supporting the lower surface therefrom; a pair of hinges, each mounted to a beam, having their axes parallel to the plane of the beam web and inclined in like direction spanwise from the vertical; a pair of truss members each pivotally mounted about one end, on one of said hinges and having a pivotal interconnection at their other end; and actuating means for rotating the truss members about their canted hinges so as to apply a chordwise contraction force between the pair of parallel beams to shorten the lower surface and bend the upper surface to increase its curvature thereby increasing the camber of the airfoil.

Claim 7

A variable camber airfoil comprising: an upper surface; a contractable lower surface; a pair of parallel beams extending from the upper surface to the lower surface, being rigidly attached to the upper surface in a spanwise direction and supporting the lower surface therefrom; a pair of hinges, each mounted to a beam, having their axes parallel to the plane of the beam web and inclined in like direction spanwise from the vertical; a pair of truss members each pivotally mounted about one end, on one of said hinges and having a pivotal interconnection at their other end; and actuating means for rotating the truss members about their canted hinges so as to apply a chordwise contraction force between the pair of parallel beams to shorten the lower surface and bend the upper surface to increase its curvature thereby increasing the camber of the airfoil.

Claim 8

The variable camber airfoil as set forth in claim 4, further including a stiffener channel extending spanwise between the parallel beams; said contractable lower surface having an overlapping slip-joint; said stiffener channel being attached to the upper surface and extending therefrom to support the overlapping slip-joint of the lower surface; and said stiffener being designed to open and close in spring-like fashion as the degree of overlap changes due to airfoil camber variations.

Claim 9

A variable camber airfoil comprising: a structurally continuous upper surface; a nonstructural, slip-jointed lower surface; a pair of hinges spaced chordwise and structurally supported from the upper surface; said hinges having their axes canted in like direction spanwise from the vertical; a pair of truss members in chordwise alignment, each pivotally mounted about one end on a canted hinge and having a pivotal interconnection at their other end below the chord plane of the airfoil actuating means for moving the pivotal interconnection of the truss members spanwise to rotate the truss members about their canted hinges and apply a contraction force to the airfoil below its chord plane which due to the slip-jointed lower surface and the relatively non-contractable upper surface, applies a bending force to the upper surface to increase its curvature thereby increasing the camber of the airfoil.

Claim 10

A variable camber airfoil comprising: a structurally continuous upper surface; a nonstructural, slip-jointed lower surface; a pair of hinges spaced chordwise and structurally supported from the upper surface; said hinges having their axes canted in like direction spanwise from the vertical; a pair of truss members in chordwise alignment, each pivotally mounted about one end on a canted hinge and having a pivotal interconnection at their other end below the chord plane of the airfoil actuating means for moving the pivotal interconnection of the truss members spanwise to rotate the truss members about their canted hinges and apply a contraction force to the airfoil below its chord plane which due to the slip-jointed lower surface and the relatively non-contractable upper surface, applies a bending force to the upper surface to increase its curvature thereby increasing the camber of the airfoil.

Claim 11

A variable camber airfoil comprising: an upper surface; a contractable lower surface; a pair of hinges spaced chordwise and supported from the upper surface; said hinges having their axis canted spanwise from the vertical; a pair of truss members each pivotally mounted about one end on a canted hinge and having a pivotal interconnection at their other end; said pivotal interconnection being translationally supported from the upper surface, and actuating means for rotating the truss members about their canted hinges to apply forces between the pair of hinges contracting the lower surface and bending the upper surface to increase its curvature and thereby increase the camber of the airfoil.

Claim 12

A variable camber airfoil comprising: an upper surface; a contractable lower surface; a pair of hinges spaced chordwise and supported from the upper surface; said hinges having their axis canted spanwise from the vertical; a pair of truss members each pivotally mounted about one end on a canted hinge and having a pivotal interconnection at their other end; said pivotal interconnection being translationally supported from the upper surface, and actuating means for rotating the truss members about their canted hinges to apply forces between the pair of hinges contracting the lower surface and bending the upper surface to increase its curvature and thereby increase the camber of the airfoil.