Variable length blade

Claim 2

A variable length blade having a feathering axis and a blade tip end and including: a. an inner blade portion, b. an outer blade portion mounted for telescopic action with respect to said inner blade portion, c. means to cause said outer and inner blade portions to telescope with respect to one another including: 1. a threaded jackshaft located within said inner blade portion and being fixed except for rotation with respect to said inner blade portions, 2. a plurality of nut members threadably engaging said jackshaft, d. elongated tension-torsion straps connecting each of said nut members to said outer blade portion.

Claim 3

a plurality of nut members threadably engaging said jackshaft, d. elongated tension-torsion straps connecting each of said nut members to said outer blade portion.

Claim 4

a plurality of nut members threadably engaging said jackshaft, d. elongated tension-torsion straps connecting each of said nut members to said outer blade portion.

Claim 5

Apparatus according to claim 1 and including means to cause said jackscrew to rotate and hence vary the position of the outer blade portion with respect to the position of the inner blade portion to thereby vary blade length.

Claim 6

a plurality of substantially equally sized nuts threadably engaging said jackscrew,

Claim 7

a plurality of substantially equally sized nuts threadably engaging said jackscrew,

Claim 8

an outer blade portion mounted for telescoping motion with respect to said inner blade portion,

Claim 9

an outer blade portion mounted for telescoping motion with respect to said inner blade portion,

Claim 10

a plurality of nut members engaging said jackscrew and adapted to contact the inner wall of the inner blade portion after a predetermined degree of relative angular movement,

Claim 11

a plurality of nut members engaging said jackscrew and adapted to contact the inner wall of the inner blade portion after a predetermined degree of relative angular movement,

Claim 12

a plurality of tension-torsion members individually connecting said nut members to the outer blade portion.

Claim 13

a plurality of tension-torsion members individually connecting said nut members to the outer blade portion.

Claim 14

means to cause said outer blade portion to telescope with respect to said inner blade portion including: A. a jackscrew member mounted for rotation within said inner blade member, B. a plurality of substantially equal sized nuts threadably engaging said jackscrew member, C. a plurality of tension-torsion straps extending between and connected to each of said nuts and said outer blade portion.

Claim 15

means to cause said outer blade portion to telescope with respect to said inner blade portion including: A. a jackscrew member mounted for rotation within said inner blade member, B. a plurality of substantially equal sized nuts threadably engaging said jackscrew member, C. a plurality of tension-torsion straps extending between and connected to each of said nuts and said outer blade portion.

Claim 16

a plurality of elongated tension-torsion straps extending between and connected to each of said nuts and said outer blade portion.

Claim 17

a plurality of elongated tension-torsion straps extending between and connected to each of said nuts and said outer blade portion.

Claim 18

Apparatus according to claim 2 wherein said jackscrew rotating means constitutes means to cause said jackscrew to rotate in either direction.

Claim 19

Apparatus according to claim 1 wherein said tension-torsion straps connect to said blade outer portion at the blade tip end.

Claim 20

Apparatus according to claim 1 and wherein said jackshaft is concentric with respect to said inner and outer blade portions.

Claim 21

Apparatus according to claim 1 wherein said straps are of selected length and physical properties to distort under blade centrifugal loading sufficiently to substantially equally load each of said nuts.

Claim 22

Apparatus according to claim 1 wherein said blade portions are mounted for pitch change motion about said feathering axis and including means to cause said blade portions to change pitch about the blade feathering axis without causing motion of said nut members on said jackshaft.

Claim 23

A variable length blade including: a. an inner blade portion, b. an outer blade portion mounted for telescopic motion relative to the inner portion, c. means to cause said outer and inner blade portions to telescope with respect to one another including:

Claim 24

A variable length blade including: a. an inner blade portion, b. an outer blade portion mounted for telescopic motion relative to the inner portion, c. means to cause said outer and inner blade portions to telescope with respect to one another including:

Claim 25

A variable lengTh blade having a blade tip and including: a. an inner blade portion, b. an outer blade portion supported from said inner blade portion for telescoping motion with respect thereto, c. means to cause said outer blade portion to telescope with respect to said inner blade portion including:

Claim 26

A variable lengTh blade having a blade tip and including: a. an inner blade portion, b. an outer blade portion supported from said inner blade portion for telescoping motion with respect thereto, c. means to cause said outer blade portion to telescope with respect to said inner blade portion including:

Claim 27

Apparatus according to claim 9 wherein said blade portions are mounted for feathering action about the blade feathering axis and including means to cause said blade portions to move about said blade feathering axis to vary blade pitch without causing said nuts to rotate on said jackshaft.

Claim 28

Apparatus according to claim 11 wherein said inner blade portion is hollow and of substantially elongated cross-section, and wherein said nuts are also shaped to be elongated in the same direction as the elongation of said inner blade portion so that during pitch change motion said blade portion can rotate a preselected angular amount relative to said nuts and, further, wherein as said jackscrew is caused to rotate to thereby cause said outer blade portion to telescope with respect to said inner blade portion, said nuts abut the inner wall of said inner blade portion to prevent rotation of said nuts.

Claim 29

Apparatus according to claim 9 and wherein said nuts are of the wing-nut variety and are staggered with respect to one another on said jackshaft so that the wings of each of said nuts are out-of-alignment with the wings of the remainder of the nuts and so that said tension-torsion straps extend interference-free from the wings of each nut to the blade outer portion.

Claim 30

Apparatus according to claim 9 wherein said nuts are pinned together to prevent relative rotation therebetween while permitting simultaneous translation of all nuts along said jackshaft and relative translatory motion between said nuts along said jackshaft.

Claim 31

Apparatus according to claim 9 and including positive stop means to limit the amount of rotation of said nuts within said inner blade portion.

Claim 32

Apparatus according to claim 9 wherein said inner blade portion is of elliptical shape and wherein said nuts are of elliptical shape and positioned within said inner blade position so that said inner blade portion is capable of limited relative rotation with respect to said nuts and wherein said nuts abut said inner blade portion to prevent rotation of said nuts with said jackshaft.

Claim 33

Apparatus according to claim 9 including means to limit the end travel of said outer blade portion with respect to said inner blade portion.

Claim 34

Apparatus according to claim 9 wherein said tension-torsion straps are flat members and wherein said nuts are of the wing-nut variety and wherein one end of each tension-torsion strap connects to one of the wings of one of said nuts, and including bolt means connecting the end of the strap to the nut wing.

Claim 35

Apparatus according to claim 17 wherein the wings of each nut include an arcuate surface, and including bolt means connecting a strap end to the nut wing at a station on the wing away from the blade tip so that the strap engages and is supported by said wing arcuate surface.

Claim 36

Apparatus according to claim 9 wherein said nuts are identical in shape and positioned in alignment on said jackscrew and include a plurality of aligned holes through said nuts, and further wherein said tension-torsion straps are wires with each strap extending through a series of aligned nut holes, and further including a plate member connected to the blade outer portion at the blade tip and including a plurality of holes therethrough in substantIal alignment with the aligned holes of the nuts and wherein said straps pass through said holes of said plate member, and still further including means to connect each of said straps to said plate member and one of said nuts.

Claim 37

A variable diameter rotor including: a. a plurality of equally spaced blades mounted for rotation about an axis of rotation, b. each of said blades including:

Claim 38

A variable diameter rotor including: a. a plurality of equally spaced blades mounted for rotation about an axis of rotation, b. each of said blades including:

Claim 39

Apparatus according to claim 20 wherein the number of threads on each of said nuts is small in comparison to the number of threads in said jackscrew.

Claim 40

Apparatus according to claim 21 wherein each of said nuts has an equal number of threads.

Claim 41

Apparatus according to claim 20 wherein said torsion straps are rod members having a fixed head at one end thereof and an adjustable head at the opposite end thereof and including: a. a series of aligned drilled holes extending through said nuts, b. a plate member attached to said outer blade portion at the blade tip and including drilled holes passing therethrough in alignment with said aligned drilled holes and wherein said straps extend through said aligned drilled holes of said nuts and said plate member and are retained therein by the coaction between said fixed and adjustable heads of the straps, said nuts and said plate member to thereby form a connection between the nuts and the blade outer portion through said straps.