VENDTRUMMA FOR OMSTELLBARA SKON- OCH VIDERTRYCKMASKINER

摘要

A sheet-turning drum assembly for printing machines convertible from printing on one side of a sheet to printing on both sides of a sheet and from printing on both sides of a sheet to printing on one side of a sheet includes a drum and tongs-type grippers pivotally mounted on the drum and including a pair of tongs-type gripper halves. Separate drive members are operatively connected to the respective tongs-type gripper halves for controllably pivoting each of the tongs-type gripper halves, and a torsion bar spring is disposed between the separate drive members for mutually bracing the latter resiliently against one another.