Medical or dental motorized instrument

摘要

The instrument has a straight or angled handpiece (1) with a drive shaft (6) fitted with an instrument tool, supported for rotation about its centre axis (8) at the front end of the instrument, via at least one roller bearing (11,12). The bearing has a blocking ring, acting between the inner and outer bearing rings, for preventing penetration of water or soiling particles, which is laser welded to either the inner bearing ring or the outer bearing ring.