| 摘要 |
An air-turbine type dental handpiece in which the handle has separate passages for air and water under pressure respectively to drive the turbine to rotate a bur and furnish cooling water to the bur which has an axial passage entirely therethrough to direct the cooling water where the cutting end of the bur contacts tooth material for producing a dental preparation to receive filling material and the like. The head of the handpiece has a chamber within which the turbine and bearings are mounted and also includes a rotary coupling to direct cooling water to the inner end of the axial passage of said bur and prevents escape of the cooling water to the interior of the chamber for the turbine and bearings. The coupling is bipartite and one of the parts comprises the innermost end of the bur when mounted within the shaft of the turbine. Control mechanism to furnish and regulate the pressure of air and water to the handpiece also comprises part of the invention and an anti-clogging device is included in the passage in the bur. |
