Electromagnetic bearing for watch mounting - uses hollow cylindrical permanent magnetic rotor fitted over spherical boss in centre of electromagnetic stator

摘要

The electromagnetic torque converter for a watch mounting consists of a rotor magnet (21) with an axial opening (40) which has a diameter greater than the spherical shaped bearing (42). The latter is mounted on a bearing spindle (43) which is fixed to the backing plate (10). The rotor is pushed down in a verticla direction (48) until its upper surface is in the same plane as the stator (22) of the bearing. In this position it is stable as a movement in any direction is resisted by magnetic forces between the rotor and stator. the rotor may form part of a larger assembly with an upwardly extending spigot of plastics beign located in the top cover plate.