Bearing mechanism for a dental handpiece

摘要

A bearing for an air driven turbine operated dental handpiece of the type including a turbine rotor provided in a casing and having blade elements coupled to a shaft member. The bearing includes a first air bearing formed circumferentially about the shaft member, a second air bearing including a small gap formed between the end of the shaft and an inside surface of the casing and a means for introducing compressed air into the small gap and a pair of opposed magnets of the same polarity provided respectively in the end of the shaft member and the inside surface of the casing whereby the axial load on the turbine rotor is resisted not only by the second air bearing but also by the magnetic repulsive force of the magnets.