| 摘要 |
<p>An axially slidable chuck-actuating internal sleeve of a dental handpiece is biased to a chuck-closing position by a spring, but can be displaced to open the chuck by cooperation with radially-movable balls. These balls are biased outwardly by leaf springs to normally rest in contact with the inner surface of an axially slidable or rotatable external actuating sleeve, whereby the balls remain out of contact with the internal sleeve when it is rotated with the handpiece shaft.</p> |
