| 摘要 |
<p>Chopper action folding apparatus for high speed printing or similar processing plant is shown diagrammatically in Figure 3. A conveyor (10) feeds signatures (12) towards a headstop (20). A vertical chopper blade (24) extending along the centre of the feed path is oscillated to initiate longitudinal folding of each signature as it is pressed downwards into a nip between longitudinal folding rolls (22) below the feed path which complete the folding process by drawing the signature downward. Brush or other braking means (26) slow or stop the approaching signatures before or as they reach the headstop so that they are folded without damage, the braking pressure being automatically regulated by control means (30) including infra-red or other position sensing means (32) which detects the relative positions of the headstock and approaching leading edge (14) of each signature for optimum operation. <IMAGE></p> |
