Printing cylinder

Claim 1

A plate clamping arrangement for a reversible printing cylinder comprising, in combination, a flexible printing plate having flanged and slotted leading and trailing edges formed essentially at right angles to the plate principal surface, a longitudinal trough formed in the surface of said cylinder and defined in part by leading and trailing trough edges, a substantially U-shaped spring member mounted in said trough and extending longitudinally of said cylinder, said spring member having spaced apart, upstanding leg elements each having plate engaging finger elements at the free ends thereof, rotatable elongated cam means mounted in said trough intermediate said leg elements and operable to position the respective leg elements selectively in a printing plate leading edge clamping position wherein the said flangeD and slotted leading edge of the plate is clamped between the finger elements and the said trough leading edge or in a printing plate trailing edge tensioning position wherein said finger elements engage the flanged and slotted trailing edge of said plate and bias it circumferentially away from said trough trailing edge, first means on each of said leg elements for engaging the slots in the flanged leading edge of said plate to radially restrain the said leading edge of said plate when said leg element is positioned in the said plate leading edge clamping position, and second means on each of said leg elements for engaging the slots in the flanged trailing edge of said plate to radially restrain the said trailing edge of said plate when said leg element is positioned in said plate trailing edge tensioning position.