VIBRATION DAMPER FOR HELICOPTER MAIN ROTOR

摘要

FIELD: vibration dampers for helicopter main rotors. ^ SUBSTANCE: proposed vibration damper has main member which is set in motion by means of drive member and rigid member for mounting the damper on load-bearing structure; proposed damper is also provided with damping system functionally connecting the main member and rigid member for dampening vibration in at least one direction perpendicular to main axis. Damping system includes hydraulic damping unit located in chamber filled with viscous fluid and elastic unit possessing high stiffness in direction parallel to main axis and low stiffness in direction perpendicular to main axis. Hydraulic damping unit has first and second systems of flat plates whose planes are perpendicular to said main axis. First system is kept on main member by means of first mechanical coupling and second system is kept on rigid member by means of second mechanical coupling. Plates of first and second system overlap each other; they form zones of viscous damping; each of them is located between one plate of first system and one plate of second system. Hydraulic damping unit has at least one damping member located in chamber filled with viscous fluid and rigidly connected with main member. Damping member forms external loop narrowing from its base located on side of one axial end of this damper till its vertex located on side of position of flap plates. ^ EFFECT: satisfactory damping characteristics both for small and large amplitudes of deviation. ^ 3 dwg