Patent ID: 7040863
Filing Date: 2006-05-09
Classification: B64C

Abstract:
1. Variable pitch rotor blade, for a rotorcraft multi-blade, variable pitch shrouded rotor, with the blade comprising a vaned current part ( 1 ), having an aerodynamic profile ( 2 ) produced on the basis of synthetic material enclosing a spar ( 7 ) extending more or less along a longitudinal axis (X—X) for blade pitch change, said current part ( 1 ) extending according to the blade span between a blade tip ( 4 ) and a blade root ( 3 ), at least partly tubular, with a pitch sleeve ( 21 ) integral with the blade in rotation around said pitch axis (X—X), and having two pitch rotation journals ( 22 , 23 ) offset according to the pitch axis (X—X), and a pitch control lever ( 24 ) protruding toward the outside of said sleeve ( 21 ), with said blade root ( 3 ) transversed more or less along the pitch axis (X—X) by an arm ( 6 ) twisting around said pitch axis (X—X) and protruding beyond blade root ( 3 ) on the opposite side to blade tip ( 4 ), and of which one end ( 9 ) is integral with said blade root ( 3 ) in rotation around said pitch axis (X—X), and the opposed free end ( 12 ) is designed to be attached to a rotor hub, characterized in that said twisting arm ( 6 ) comprises a first part of bundle ( 5 ) of metal strips ( 5 a ) superimposed and extending along said pitch axis (X—X), and said current part ( 1 ) including a block ( 13 ) based on said synthetic material molded in form in a single piece around said spar ( 7 ), comprising a second part, of said bundle ( 5 ) of metal strips ( 5 a ) extending in an extension to said first part, forming the twisting arm ( 6 ), and cooperating with anchoring devices ( 14 , 17 ) of said block ( 13 ) based on synthetic material around said second part of bundle ( 5 ) of strips ( 5 a ).