| 摘要 |
A machine for drilling apertures in sheet metal work pieces of the type adapted for fabricating buses. The sheet metal is clamped against an inverted-U framework by straps. A movable, inverted-U, outer frame carries a plurality of inwardly extending drills for drilling holes in the sheet metal. The outer frame intermittently moves parallel to the stationary framework, by automatic indexing means, so that the drills may drill at selected, predetermined points along the length of the sheet metal work pieces. An inner frame member carries driving means for translating itself and, through drive pins, also drives the outer frame member along its path. The drive pins from the inner frame member leap-froggingly engage the outer frame member with respect to spaced uprights which support the sheet metal carrying framework. |
