US Patent 7063491 Reverse barb system for screws and nails

The reverse barb system for screws and nails includes fasteners that are barbed to prevent backing out once driven into a workpiece or construction material, such as wood. A screw with barbed threads has several barbed thread sections. Each barbed thread section is a section of thread having a leading edge and a trailing edge, the trailing edge defining a barb to increase the screw's resistance to backing out once driven into place. A nail with a barbed point is a nail having one or more barbs formed in the nail's point. Each barb is defined by a leading edge and a trailing edge. The barb's trailing edge forms an acute angle with the longitudinal axis of the nail. The barbs extend from the nail shank to prevent the nail from backing out.