Description
Class G04C : ELECTROMECHANICAL CLOCKS OR WATCHES
Subclass 3/033: Electromechanical clocks or watches independent of other time-pieces and in which the movement is maintained by electric means (clocks driven by synchronous motors G04C 15/00) wherein movement is regulated by a pendulum using torsion pendulums; using conical pendulums (construction thereof G04B 17/00)