| 摘要 |
<p>The invention relates to an injection mould against at least one of the walls of the form cavity an insert piece (5) is arranged, held in a preselected position by securing means connectable to a source for fluid under underpressure for holding, at least partially as a result of said underpressure, the or each insert piece against the wall concerned. In the case of specific objects use is made of punching means (31, 32) for punching a central hole out of a shaped object (30). Preferably the punching means (31, 32) comprise a cylindrical part which forms part of the one mould portion, said cylindrical part having a front circumferential edge (32) with a form adapted to the shape of the hole to be punched out of an object, said part being axially movable away from and towards the other mould portion, and that adjusting means are available to adjust the distance beween the frontcircumferential edge (32) and the forming surface of the other mould portion situated opposite it.</p> |
