| 摘要 |
A drill chuck for a hammer drill with a plurality of clamp jaws fed in feed channels to engage a drill in a tool holder, the clamp jaws being adjustable by means of a support ring, the support ring bearing a restraining casing having teeth thereon which can engage gearing in the support ring so as to lock it against further rotation. The restraining casing is lockable in two axial positions, in one position in engagement with the support ring, in the other out of engagement with the support ring. The restraining casing is slid into engagement with the support ring in a covering jacket which holds the restraining casing axially tightly so that drilling waste can not impede engagement of the restraining casing with the support ring. Cleaning passages run through the chuck body from the tool holder to the surroundings so that drilling waste will be removed from the tool holder and the chuck interior during drilling operation. Similarly by opening the feed channels to the surroundings, as is done for the cleaning passages, drilling waste may also leave the chuck through the feed channels as well. |
