DEVELOPMENT OF BOLT-CLAMPED LANGEVIN-TYPE TRANSDUCER WITH HIGH MECHANICAL QUALITY FACTOR FOR EXCITATION OF LARGE TORSIONAL VIBRATION

We have identified a crucial point for realization of a high mechanica l quality factor (Q) of a bolt-clamped Langevin-type transducer used t o excite large torsional vibrations of a cylindrical system. A suffici ent margin of the static bearing stress over the vibratory shearing on e at the interface between the components has been found necessary for a high Q as a result of some numerical simulations and experiments fo r two models of the transducers. A hollow cylindrical shape of the tra nsducer is seen to have a great advantage in this respect.