| 摘要 |
<p>The system prevents penetration of water into the right-angle head of a dental handpiece containing a rotary chuck for the tool. The wall at the tool end of the head contains an opening for the tool. A cylindrical sleeve (8), bored to the dia. of the tool, fits inside the head (1) coaxially to the chuck (3), and between the chuck and the end wall (5). The sleeve is a close fit where it passes through the opening (9) for the tool, and is held in place by a collar (10) which has a dia. larger than the opening. The clearance between sleeve and opening can be greater than that between the chuck and its bearing (4).</p> |
