Sheet-feeding drum for rotary printing machine

摘要

Rotary printing presses with sheet guiding drums having gripper bridges arranged about the periphery, include gripper support bars of which are adjustable to the thickness of the material to be printed. A non-central individual such adjustment of all gripper bridges together in one printing press can be effected by mounting the gripper support bars (2) so they are supported spring loaded via pressure pieces (4) on a positioning device (3). On the free end of the positioning device (3) a roller lever (6) with a roller (7) is rotatably arranged. The lever (6) may adopt a number of latch positions (9) corresponding to the number of pressure pieces (4). A latch (8) engages in the latching positions (9) which is coupled with a compression spring (10) mounted on the drum body (1). Arranged on the side frame (11) is a control cam (12) which has an upper and a lower cam path. On rotation of the drum (1), the roller (7) of the roller lever (6) runs into the control cam (12) and can be swivelled by changing of the cam paths of the control cam (12) to engage the roller lever (6) and more the positioning device (3) from one latch position to another.