Damper for rotating shaft against vibration

摘要

The damper has support ring (1) fitted to the rotating shaft and rotates with it. Two rings of permanent magnets (3) are fitted around the outer part of the ring. The damping ring (2) is fitted to the outer part of the support ring and can rotate relative to the support ring, but is axially supported on the support ring. The damping ring has a flange (4) which is set between the pairs of magnets. The magnet pairs have opposite polarity and adjacent pairs of magnets have opposing polarity. The relative rotation of the flange and the magnets induces electric currents in the flange which heat the flange. The heat is ducted away by cooling. The damping ring and the flange are provided with radial cooling holes (5) which generate a cooling airstream as the rings rotate. The cooling ducts run from the centre of the structure and duct away the heat generated by the induced current. For enhanced damping more coaxial pairs of magnets can be fitted, each pair straddling a damping flange.