In automatic watch movements, the rotation of the oscillating weight is generally driven by a ball bearing.
The rotation of the balls on the rolling areas generates vibrations in the form of acoustic waves that are favourably propagated in hard materials such as metals. As the bearing is fixed on the bridge or plate by one or more screws, the vibrations move from the inner ring through the attachment to the other components of the movement, which in turn propagate sound vibrations inside the case.
The ActiVib bearing offers a ball bearing that effectively filters the propagation of sound vibrations generated by the bearing to the other components of the movement. To this end, the ActiVib bearing incorporates a vibrations damper made of elastomeric polymer especially developed for this purpose. Laboratory tests show a decrease in sound vibrations of around 10 dBA.
September 13, 2018