Tuned torsional vibration damper

A tuned viscous torsional vibration damper comprising:

• a central hub for connecting the damper to a rotatable shaft;
• a hollow cylindrical housing with a circular inner wall surrounding the hub, a circular outer wall, and disc-shaped side walls;
• an annular-shaped inertia disc within the housing with two slots extending outwardly from the inner wall of the housing;
• a bearing between the inner wall of the housing and the inertia disc for rotation of the inertia disc within the housing;
• silicone fluid between the disc and the housing;
• two abutment plates connected to the inner wall of the housing and extending radially outwards into the slots in the inertia disc;
• disc tuning means comprising four coil springs, each coil spring extending between the disc and one of the abutment plates perpendicularly to the one abutment plate;
• a ring surrounding the hub and radially spaced-apart therefrom, the inner wall of the housing being mounted on the ring;
• and
• housing tuning means comprising a plurality of spoke springs fixedly connected to the hub at a first end, extending radially outwards between the hub and the ring and fixedly connected to the ring at a second end.