Abstract: A gripper feed devices comprises a housing, first and second tension grippers, first and second toothed rods fixedly connected to the first and second tension grippers, and a rotatable pinion meshing with the toothed rods for converting the rotational movement of the pinion into linear, symmetrical movement of the tension grippers in opposite directions. The pinion is cyclically driven, via a main shaft and a crank disk mounted on the main shaft, by two piston/cylinder arrangements connected at different points on the crank disk. The two piston/cylinder arrangements are designed to operate alternately and in opposite directions, thus imparting a cyclical rotation to the pinion. An adjusting disk mounted on the main shaft and an adjusting sled to which the piston/cylinder arrangements are connected are also provided to vary the stroke length of the piston, and thereby the extent of linear movement of the tension grippers.