Rotating mass for self-winding watch mechanism - comprises heavy metal ring embedded in plastics element

摘要

The rotating mass for a self winding watch mechanism comprises a ring (1) of heavy metal and a carrier element (2) of plastics in which the ring (1) is partially embedded. The carrier element (2) is formed and the ring (1) embedded in it in a single operation. The ring (1) may be made from sintered tungsten powder and the carrier element (2) is pref made from a thermally hardened plastics via injection moulding. The ring (1) may be plated via vacuum deposition or electro-plating in the latter case the carrier element being made from plastics made electrically conductive.