Patent ID: 6599124
Filing Date: 2003-07-29
Classification: A61C,F16C

Abstract:
A dental handpiece comprising:a burr sleeve for detachably holding a dental treatment tool therein; upper and lower ball bearings for rotatably supporting said burr sleeve, wherein said upper and lower ball bearings are angular contact ball bearings each having a bearing cage, said bearing cage having apertures for supporting balls of said ball bearings therein, said apertures being located substantially in the middle of said bearing cage in a thrust direction; a rotor fixed to said burr sleeve between said upper and lower ball bearings and rotated by compressed air for rotatably driving said burr sleeve; and a dust controller including a rotary protruding member fixed on an outer surface of said burr sleeve and rotating integrally with said burr sleeve, and a stationary protruding member attached to a stationary part of said handpiece; wherein said stationary protruding member has a radially inner end portion extended radially inwardly beyond the inner ring of the lower ball bearing, said radially inner end portion having a surface facing to said rotary protruding member to define a gap there between, said gap being located outside of said lower ball bearing; and wherein said burr sleeve has an outer surface substantially flush with an outermost surface of said rotary protruding member.