Carley Clock
The motor runs from the AC mains that generates a changing magnetic field. This causes a thin disc placed on a rotor to vibrate. The disk has tiny brushes on its surface that touch a second disc, placed in parallel. The brushes "dance" on the surface of the second disc and since they are placed under an angle make the second disc to rotate; the second disc makes vibrations in a forward direction. The backwards and forward vibration is thus converted into a rotary motion and this delivers a constant power tension to the little spring of the balance.
Patent by Johan Dirk Carley (Netherlands)