Abstract: In order to adjust desired web lengths between perforations, a perforating cutter (6) is used which consists of two mutually rotatable cutter discs (10 and 11) which can be fixed in the adjusted positions relative to each other. One cutter disc (11) has thereby a flat radial cutting surface (12) which constitutes the base of a flat truncated cone, the lateral face (16) of which corresponds to the inner lateral face (15) of a pot-shaped cutter disc (10), of which the outer lateral face (14) forms, together with the cutting face (12), a cutting edge (19) at which also terminate the lateral face (16) of one cutter disc (11) and the inner lateral face (15) of the other cutter disc (10). Provided in the cutting edge (15) and around the periphery are regularly equidistant cut-outs (24), of which the length and thus the length of the webs between the perforations can be adjusted by rotation of the cutter discs (10 and 11 ) in relation to each other.

Abstract: The invention contemplates mechanism for perforating signatures for ultimate use in glued binding of the signatures into a book. The perforating mechanism cuts chips in the course of continuous transport of the signatures, and the arrangement is such that the chips are transiently supported and transported out of the chip-cutting zone prior to forced ejection from the mechanism, thereby avoiding any fouling accumulation of retained chips at the cutting zone.