Rotor construction with elastic interconnection of opposite blades

Claim 2

A four blade rotor for helicopters comprising, a rotatable rotor head, four rotor blades symmetrically carried by said rotor head for rotation therewith about a central head axis and having root portions rotatably supported in said head for blade angle variation, and first and second endless laminated torsion-elastic loop members connecting the root portions of respective diametrically opposed rotor blades, said first endless laminated loop member passing entirely through said second endless laminated loop member, means rotatable mounting each of said blades to said rotor head, and spring means between said mounting means and said rotor head for centering each of said blades relative to said rotor head free of play.

Claim 3

A four blade rotor for helicopters comprising a rotatable head having four angularly symmetrically arranged and radially opening rEceiving sleeves for the respective rotor blades, means rotatably mounting said head for rotation about a substantially central axis, a rotor blade having a blade root sleeve rotatable mounted in each of said receiving sleeves, a clamping ring carried in said receiving sleeve and having a bolt member extending across the axis of said blade, means securing said clamping ring to said receiving sleeve for rotation with said receiving sleeve and said blade for varying the pitch angle of said blade, first and second endless loop members engaged around said bolt members of respective diametrically opposed rotor blades, said first and second endless loop members intersecting centrally within said rotor head and one of said first and second endless loop members passing through the other, a retaining nut threaded over said retaining ring and bearing against said root sleeve, said nut being threaded to shift the position of said retaining ring axially along said root sleeve for varying the tension on said first and second loop members.

Claim 4

A four blade rotor for helicopters comprising a rotatable head having four angularly symmetrically arranged and radially opening rEceiving sleeves for the respective rotor blades, means rotatably mounting said head for rotation about a substantially central axis, a rotor blade having a blade root sleeve rotatable mounted in each of said receiving sleeves, a clamping ring carried in said receiving sleeve and having a bolt member extending across the axis of said blade, means securing said clamping ring to said receiving sleeve for rotation with said receiving sleeve and said blade for varying the pitch angle of said blade, first and second endless loop members engaged around said bolt members of respective diametrically opposed rotor blades, said first and second endless loop members intersecting centrally within said rotor head and one of said first and second endless loop members passing through the other, a retaining nut threaded over said retaining ring and bearing against said root sleeve, said nut being threaded to shift the position of said retaining ring axially along said root sleeve for varying the tension on said first and second loop members.

Claim 5

A four blade rotor construction, according to claim 2, wherein said rotor head has a ledge abutment at the interior of each of said receiving sleeves, the root sleeves of each of said blades being spaced from said ledge abutment, and spring means disposed between said root sleeve and said ledge abutment and centering each of said root sleeves around said head free of play.

Claim 6

A four blade rotor construction, according to claim 2, wherein said means mounting said root sleeve within said rotor head receiving sleeve comprises two axially spaced roller bearing sets.

Claim 7

A four blade rotor for helicopters comprising a rotatable rotor head, four rotor blades symmetrically carried by said rotor head for rotation therewith about a central head axis and having root portions rotatably supported in said head for blade angle variation for rotation about axes lying in substantially a common plane, and first and second endless laminated torsion-elastic loop members connecting the root portions of respective diametrically opposed rotor blades, said first endless laminated loop member passing entirely through said second endless laminated loop member, said first endless laminated loop member having laminations which are arranged substantially in a vertical plane, said second endless laminated loop member having laminations which are arranged in a substantially horizontal plane.

Claim 8

A four blade rotor for helicopters comprising a rotatable rotor head, four rotor blades symmetrically carried by said rotor head for rotation therewith about a central head axis and having root portions rotatably supported in said head for blade angle variation for rotation about axes lying in substantially a common plane, and first and second endless laminated torsion-elastic loop members connecting the root portions of respective diametrically opposed rotor blades, said first endless laminated loop member passing entirely through said second endless laminated loop member, said first endless laminated loop member having laminations which are arranged substantially in a vertical plane, said second endless laminated loop member having laminations which are arranged in a substantially horizontal plane.

Claim 9

A four blade rotor for helicopters comprising a rotatable rotor head, four rotor blades symmetrically carried by said rotor head for rotation therewith about a central head axis and having root portions rotatably supported in said head for blade angle variation for rotation about axes lying in substantially a common plane, first and second endless laminated torsion-elastic loop members connecting the root portions of respective diametrically opposed rotor blades, said first endless laminated loop member passing entirely through said second endless laminated loop member, and means carried by each of said rotor blades adjacent their root portions for adjustably connecting and tensioning the associated first and second endless laminated loop members.

Claim 10

A four blade rotor for helicopters comprising a rotatable rotor head, four rotor blades symmetrically carried by said rotor head for rotation therewith about a central head axis and having root portions rotatably supported in said head for blade angle variation for rotation about axes lying in substantially a common plane, first and second endless laminated torsion-elastic loop members connecting the root portions of respective diametrically opposed rotor blades, said first endless laminated loop member passing entirely through said second endless laminated loop member, and means carried by each of said rotor blades adjacent their root portions for adjustably connecting and tensioning the associated first and second endless laminated loop members.

Claim 11

A four blade rotor for helicopters comprising a rotatably rotor head, four rotor blades symmetrically carried by said rotor head for rotation therewith about a central head axis and having root portions rotatably supported in said head for blade angle variation for rotation about axes lying in substantially a common plane, first and second endless laminated torsion-elastic loop members connecting the root portions of respective diametrically opposed rotor blades, said first endless laminated loop member passing entirely through said second endless laminated loop member, a bolt member extending across the axis of each of said blades with which said respective ones of said first and second endless laminated loop members are engaged, and means adjustably positioning said bolt member on each of said blades.

Claim 12

A four blade rotor for helicopters comprising a rotatably rotor head, four rotor blades symmetrically carried by said rotor head for rotation therewith about a central head axis and having root portions rotatably supported in said head for blade angle variation for rotation about axes lying in substantially a common plane, first and second endless laminated torsion-elastic loop members connecting the root portions of respective diametrically opposed rotor blades, said first endless laminated loop member passing entirely through said second endless laminated loop member, a bolt member extending across the axis of each of said blades with which said respective ones of said first and second endless laminated loop members are engaged, and means adjustably positioning said bolt member on each of said blades.

Claim 13

A fouR blade rotor for helicopters comprising a rotatable rotor head, four rotor blades symmetrically carried by said rotor head for rotation therewith about a central head axis and having root portions rotatably supported in said head for blade angle variation for rotation about axes lying in substantially a common plane, first and second endless laminated torsion-elastic loop members connecting the root portions of respective diametrically opposed rotor blades, said first endless laminated loop member passing entirely through said second endless laminated loop member, a sleeve having a cross bolt therethrough, means adjustably mounting said sleeve in respective ones of each of said root portions for radial inward and outward adjustment, said first and second endless laminated loop members being looped over corresponding diametrically opposite cross belt bolts of said blades.

Claim 14

A fouR blade rotor for helicopters comprising a rotatable rotor head, four rotor blades symmetrically carried by said rotor head for rotation therewith about a central head axis and having root portions rotatably supported in said head for blade angle variation for rotation about axes lying in substantially a common plane, first and second endless laminated torsion-elastic loop members connecting the root portions of respective diametrically opposed rotor blades, said first endless laminated loop member passing entirely through said second endless laminated loop member, a sleeve having a cross bolt therethrough, means adjustably mounting said sleeve in respective ones of each of said root portions for radial inward and outward adjustment, said first and second endless laminated loop members being looped over corresponding diametrically opposite cross belt bolts of said blades.

Claim 15

A four blade rotor for helicopters comprising a rotatable rotor head, four rotor blades symmetrically carried by said rotor head for rotation therewith about a central head axis and having root portions rotatably supported in said head for blade angle variation for rotation about axes lying in substantially a common plane, and first and second endless laminated torsion-elastic loop members connecting the root portions of respective diametrically opposed rotor blades, said first endless laminated loop members passing entirely through said second endless laminated loop member, said first endless laminated loop member extending substantially vertically and having horizontal lamina, said second endless laminated loop member extending horizontally and having substantially vertical arranged lamina.

Claim 16

A four blade rotor for helicopters comprising a rotatable rotor head, four rotor blades symmetrically carried by said rotor head for rotation therewith about a central head axis and having root portions rotatably supported in said head for blade angle variation for rotation about axes lying in substantially a common plane, and first and second endless laminated torsion-elastic loop members connecting the root portions of respective diametrically opposed rotor blades, said first endless laminated loop members passing entirely through said second endless laminated loop member, said first endless laminated loop member extending substantially vertically and having horizontal lamina, said second endless laminated loop member extending horizontally and having substantially vertical arranged lamina.