Rock fastener machine

Abstract

In an apparatus for forming loop fasteners on wirebound container blanks wherein wire manipulations are performed on a wire section secured to a container blank to form a loop in the wire and drive the end of the wire into the container blank to perpetuate the loop, first and second crossbars are provided which are respectively vertically reciprocally mounted above and transversely of the path of travel of the container blank with wire manipulating means mounted on the first crossbar including means for bending the wire section into a loop when the first crossbar is in its lowered position and means positioned to be engaged and driven by the second crossbar, during downward movement thereof, for forming a prong in the wire section, after the loop is formed, and driving the prong into the container blank material. The bending means bends the wire over a hook-like extension on a loop bar of the prong forming and driving means, and the latter includes a former bar that engages the end of the wire overlying the hook-like projection and bends it downwardly, in response to downward movement of the second crossbar, to form a prong which is supported on its inside by the hook-like extension and on its other three sides by the walls of a groove in the former bar. A driver bar then drives the formed prong through the face material of the container blank while camming the hook-like extension progressively out of the way.