摘要 |
<p>A printing machine which has a printing cylinder (1) having automatically incremented numbering barrels (2) includes drive means (40-45) which normally maintain the printing cylinder in speed and phase synchronisation with a train of documents on a web (11). The drive means is operable to decelerate the printing cylinder and then to cause the printing cylinder to regain its normal operating speed so that the web overtakes the printing cylinder by a selected distance before the next printing nip is formed.</p> |