Propeller, in particular for helicopter, having friction damper for the pivoting movement of the fluegelblaetter in the plane of rotation

摘要

787,848. Friction-type vibration dampers. SAUNDERS-ROE, Ltd. Oct. 4, 1955 [Oct. 26, 1954], No. 30853/54. Class 108(3) [Also in Group XXXIII] The invention relates to a helicopter rotor (see Group XXXIII) in which movement of the blades about their drag hinges is restrained by damping units each of which combines the actions of a snubber strut and a friction damper. As shown, two sets of friction segments 21 21A are pivotally connected to respective flanges of a piston 118. A cone 25 acts via hardened steel balls 23, carried in a cage 24, on a conical bore defined by the set of segments 21. A rubber spring 26 is interposed between a flange 27 rigid with the piston 118 and the cone 25. The cage has lugs which enter spaces between adjacent segments (Fig. 2, not shown). A similar cone 25A acts on the segments 21A under the action of a flange 27A rigid with the piston rod 19. Under no-load, the segments 21 and 21A are parallel with the wall of an outer cylinder 16 and the arrangement is such that there is no damping force for small relative movements between the piston and cylinder. A single acting damper is also described. The springs 26 may alternatively be of metal or may be pneumatic.