| 摘要 |
<p>This invention relates to apparatus for positioning sheet material on a support table (40, 41), prior to making holes in the sheet material by punching. The apparatus comprises two positioning blocks (1, 2 means 7, 8, 9, 20, 21) linking the blocks for synchronous movement towards or away from a centre line between the blocks, a first block (2) being movable, independently of the second block (1), from an operative position in which the first block is engaged with a sheet to be positioned to an inoperative position in which the first block is not engaged with the sheet. One or more further blocks can be provided, each movable in synchronism with the block (2) and movable independently of the block (1) in the same way as the block (2), so that the apparatus can provide, depending on which block is placed in its operative position, two or more different working centre-lines.</p> |
