Self-filling staple fastener

Abstract

A staple fastener is provided with filler material disposed between its leg portions for filling a cavity in a substrate, which cavity is formed above a head of the staple when the staple is driven into the substrate. The filler material extrudes from the staple as it is driven into the substrate. In accordance with the preferred method, the staple fasteners are driven into the substrate with a power tool applicator to form the cavity and then a tampering plunger tamps the extruded filler material to conform to the surface of the substrate. In the preferred method, a first plunger is actuated first to drive the staple; and a second tamping plunger at an angle to the first plunger is actuated after the first plunger is retracted to tamp the material into cavity and then to smooth the exterior surface of the filler material to conform to the adjacent surface. Preferably, the first plunger causes the filler material to be driven into an opening for the second plunger; and, after the lower end of the plunger lifts from the head of the staple and exposes the cavity, the second plunger pushes the filler material into the cavity to fill the cavity and tamps the filler material in the cavity.

Dependencies are inferred from the claim text.