Abstract: For the conveying of work pieces from one treatment step to the next and for release after the treatment, gripping devices are arranged at gripper rails that can be lifted and lowered wherein the lowest and the highest position of the gripper rails can be adjusted via a pulley that can be placed against cam parts carried along by the slide of the press, via a step-up gear and a lever system. The change of the gripping devices is to be carried out together with the tool change. For this purpose, the gripper rails are led into the lowest position, which position can be adjusted via a regulating means independently from the position of the slide.

Abstract: A press unit having gripper rails to be exchanged at the same time as the tools, wherein in hollow spaces of the ends of the gripper rails, means are inserted for the locking of the form-fitting or toothed connection of gripper rails on the side of the press and gripper rails on the side of the tool that are to be connected with one another for the transfer of workpieces. The device comprises a control element, a pressing rod that can be acted upon by the control element, and a locking member connected to said pressing rod, with said locking member being slidable in a preferably press side end of the gripper rails and a mating piece for receiving the locking member during the form-locking or toothed connection of the ends of the gripper rails and being slidable in an end at the side of the tool.

Abstract: An apparatus for driving a pair of gripper bars of a multi-stage press in a longitudinal direction of the press which includes a pair of driven levers disposed symmetrically to a longitudinal center plane of the press, which levers are engageable with a slide guide extending at right angles to the longitudinal direction of the press. At least one feed cross member is operatively connected to the pair of gripper bars and also to the slide guide associated with the pair of driven levers. Two toothings are provided which are disposed symmetrically to the longitudinal center plane and are conjointly reciprocatingly driven between two end positions. Each toothing meshes with a pinion mounted for rotation and fastened to the frame with the pinions having a rotational path between the two end positions of the toothing which amounts to 180.degree.. Each pinion is also rotationally fixed to one of the pair of driven levers.