| 摘要 |
PURPOSE:To prevent positional shift of laminated printedboards, when a plural ity of laminated printedboards are bored, by pressing the printedboards continu ously through a pressure foot during lifting/lowering work of drill. CONSTITUTION:A cylinder 9 lowers to contact a pressure foot 5 with a protec tion plate 2 so as to press the vicinity of boring position. At the same time, a spindle 10 slides down in the pressure foot 5 and a drill 6 passes through an opening 5b to contact with the protection plate 2 and a printedboard 1 thus starting boring. Air flows in through a groove and the opening 5b into the pressure foot 5e to produce an air flow. The air flow carries chips to a dis charge port 7 and collects them in a dust collection hose 8. Then only the spindle 10 lifts and the drill 6 is separated from the printedboard 1. Thereafter, the spindle 10 lowers again to bore the second layer printedboard 1. The opera tion is repeated and boring work is finished when the drill 6 reaches a backup plate 3. |
