| 摘要 |
PURPOSE: To provide a motorized hand piece for medical treatment, desirably for a medical or dental treatment room, by assuring a compact structure, and improving the seal performance. CONSTITUTION: Between the inner ring 114a and the outer ring 114b of a forward bearing supporting a driving shaft for tools in a revolvable manner, a seal disk 146a is installed, and moreover one or two seal disks 146b and 146c are installed in front of the seal disk 146a. The seal disk 146b adjoining the seal disk 146a co-operates with both the inner ring 114a and outer ring 114b. |
