DEVICE FOR MOVING A CARRIAGE OR THE LIKE IN A DIRECTION WITH AN ESSENTIALLY CONSTANT SPEED AND ITS RETURN WITH A UNEQUAL SPEED

摘要

An apparatus is disclosed which serves to move a carriage in one direction over a predetermined distance at a substantially uniform velocity and to return the carriage at a varying velocity so that a film web delivered at a constant velocity is intermittently advanced relative to a welding device fixed to a frame. The apparatus comprises a lever, which is adapted to be pivotally oscillated by a drive and which by virtue of a first guide provided on the lever and a slider or roller cooperating with the guide imparts a motion to the carriage. The carriage is movable on track rods in a plane which is parallel to the plane in which the lever is pivotally movable. In order to provide an apparatus which is compact and space-saving, the lever is driven by a crank, which revolves in a plane parallel to the plane in which the lever is pivotally movable. The crank is carried by a driven crankshaft and carries a crankpin, which carries a slider or a roller, which is movable in a second guide provided on the lever, which second guide is provided on the lever, which second guide is disposed on a side of the lever opposite the side in which the first guide is provided.