| 摘要 |
A machine to facilitate the mounting of flexographic printing plates and for obtaining proofs thereof. The machine includes an impression cylinder supported for rotation on a fixed axis, the impression cylinder making contact with printing plates on a plate cylinder and rotating concurrently therewith to print a proof on the impression cylinder. The plate cylinder is movable from a proofing state in which it makes contact with the impression cylinder to a mounting state in which it is separated therefrom. The flexographic printing plate to be mounted is provided with registration holes and lies on a support tray shiftable from a retracted position displaced from the plate cylinder in its mounting state to an operative position in which its leading edge is parallel to the axis of the plate cylinder and tangentially engages the surface thereof. Located on the tray are registration pins whose sites are adjustable so as to place the pins within the registration holes of the printing plate, the front margin of the plate then overhanging the leading edge of the tray and overlying the plate cylinder. The surface of the plate cylinder is sticky and the front margin of the plate is adhered thereto. The printing plate is then disengaged from the pins and the plate cylinder is rotated to transfer the remainder of the printing plate onto its surface, after which the tray is retracted to permit the plate cylinder on which the printing plate is now mounted, to be moved from its mounting state to its proofing state in which the printing plate engages a proof sheet on the impression cylinder.
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