| 摘要 |
As a means of providing for a register-true chucking of printing plates to a plate cylinder for an offset printing press, the plate cylinder is provided with a seating surface for receiving thereon a forward edge of the printing plate and a series of chuck levers for clamping the plate against the seating surface. The chuck levers pivot about a common shaft extending axially with the cylinder and are driven by means of articulated link arrangements extending from a rotatable shaft parallel with the pivot shaft. The levers are divided into first and second types, the first type having a coupler linkage designed as a pressure spring and the second type having non-resilient linkage means such that the first group of levers engage the plate ahead of the second group. The levers are each formed with a clamp surface. The clamp surface of the levers and pressure surface on the cylinder are formed with grip means for locking the forward edge of the plate onto the pressure surface. The gripping means for the second type of levers comprises a stamping device for cutting and fitting sections of the printing plate into corresponding recesses formed in the pressure surface of the plate cylinder. The grip means for the first type of levers comprises corresponding pin and perforation devices.
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