| 摘要 |
<p>A drill has a housing formed with an outlet hole, a fan expelling an air stream from the outlet hole, a drive spindle projecting from the housing adjacent the outlet and centered on and rotatable about an axis, and a chuck body carried on the housing. A tightening sleeve rotatable about the axis on the chuck body carries a plurality of radially shiftable jaws, and interengaging screw formations operatively engaged between the body and the sleeve can shift the jaws radially in the guides on rotation of the sleeve relative to the body. A shield sleeve angularly fixed to the housing and surrounding the tightening sleeve has a rear end juxtaposed with the housing radially outside the outlet hole such that the air stream enters the shield sleeve. Inside the shield sleeve forward of its rear end a passage and a particle-expelling hole collect drilling particles and blow them out the particle-expelling hole.</p> |
