Three ball rotating pendulum display for clock - has elastic fixing for suspension of pendulum powered by impulses from second shaft

摘要

The three ball rotating pendulum (1) is hung by a torsion wire or tape (11) from a fixing (14, 15, 17) which is elastic in that it contains a spring permitting natural adjustment in the vertical direction. The pendulum is restrained from over-rotating by a projection (35) attached to the pendulum which can strike a fixed pin (8b). The pendulum has a fixed natural frequency of about eleven seconds but is forced to oscillate with a frequency of ten seconds by means of an intermittent force applied by the six spokes (25a) of a wheel (25) driven by the second shaft (27) of the clock. This wheel is driven via a spring (30) which ensures a smooth application of just sufficient drive to turn the pendulum at this frequency.