| 摘要 |
Gripper control for a cyclically swingably driven pregripper for transporting single sheets in a sheet-fed printing press, the pregripper having at least one sheet gripper mounted on a free end of a swivel lever motorizingly pivotable about a frame-fixed swivel shaft, the gripper control including cams for forcibly moving the sheet gripper about an articulated shaft oriented parallel to the swivel shaft so as to close and open the sheet gripper upon sheet acceptance and sheet transfer, one of the cams being revolvable in a single revolution for cyclically shifting the other of the cams in the position thereof, the other of the cams being secured to a roller lever supported pivotally at a fixed location and having a cam roller resting on the one cam, relative positions of the cams being adjustable for determining the instants of closing and opening of the gripper, the other of the cams being a cam segment having two successive circular cam regions with radii of curvature of different length and a common center point, the cam segment being adjustable equidistantly to the circular cam regions with respect to the roller lever, the one cam revolving in a single revolution being effective for opening the gripper and the cam segment being effective for closing the gripper.
|
