Patent ID: 6280141
Filing Date: 2001-08-28
Classification: B64C

Abstract:
A pitch control system of blades of a gyroplane rotor on which each blade is, firstly, rotated around an axis of rotation of a rotor shaft by means of a hub fixed to rotate with the shaft, and, secondly, fixed in rotation, around a longitudinal pitch change axis of the blade, with at least a pitch lever controlled by a corresponding pitch rod, connected to a rotating plate rotating with the rotor and belonging to a swash-plates assembly in which the rotating plate is mounted to rotate on a non-rotating plate, held by at least a non-rotating connecting part connecting the non-rotating plate to a structure of the gyroplane, the two plates being annular, surrounding the rotor axis, and being able to be translated parallel to the rotor axis and inclined in every direction around the rotor axis, under the action of control actuators connecting the non-rotating plate to the structure, in order to control respectively the collective pitch and the cyclic pitch of the blades, wherein the rotating plate is fixed to rotate with the rotor by a rotating plate driver, including two rigid rotation driving tracks, extending at least in part substantially axially, parallel to the rotor axis, diametrically opposite in relation to the rotor axis and fixed in rotation with one at least of two parts which are the hub and the rotor shaft, each track engaging with respectively one of two opposite on this rotating plate, one of the two engaging elements which are a track and a finger having two webs between which the other element is engaged, with the result that each driving finger follows on the corresponding track a rectilinear trajectory, parallel to the rotor axis, in the case of change of the collective pitch, and a circular arc trajectory centered on the rotor axis in the case of cyclic pitch change.