Patent ID: 6113352
Filing Date: 2000-09-05
Classification: B64C

Abstract:
A rotor of the so-called ""hingeless"" type for a rotor aircraft, including:a hub, intended to be rotated around a rotor axis, andat least two blades, each of which is, on the one hand, connected to the hub by a root part including at least one strip torsionable around a longitudinal pitch change axis of the blade, and flexible at least in flapping in a direction substantially perpendicular to the pitch axis and substantially parallel to the rotor axis, and, on the other hand, is provided with a torsionally rigid blade root oversleeve, which is torsionally integral with the blade and the torsionable strip around the pitch axis, on the side of the outer axial part of the oversleeve relatives to the hub and along the pitch axis, whereas the inner axial part of the oversleeve surrounds the strip without contact, to which the oversleeve is connected by two laminated, spherical support half-bearings, substantially concentric on the pitch axis, and each comprising a stack of alternatively rigid and elastomer sphere portions between two rigid frames, one of which is an inner radial frame, relative to the pitch axis, held supported against one face of the strip, and the other of which is an outer radial frame fixed to the oversleeve, which supports a pitch lever projecting outwards from the oversleeve, wherein each of the two rigid outer frames is integral with respectively one of two rigid double horns extending transversely to the strip on both sides of the strip and the half-bearings, and, so that the ends facing one another on the two double horns, on each side of the strip and the two half bearings, are compressed towards each other and against one of respectively two struts placed between said facing ends of said double horns, so as to ensure a calibrated compression pre-stress of the laminated half bearings.