Screw having workpiece drilling and thread cutting point

Claim 1

A SCREW OF THE TYPE DESCRIBED COMPRISING AN ELONGATED SHANK, AND MEANS INTEGRAL WITH A TRAILING END OF THE SHANK AND INTERENGAGEABLE WITH A TOOL FOR TURNING THE SCREW, SAID SHANK COMPRISING A FORGED ENTERING END PORTION INCLUDING A TRANSVERSELY DISPOSED END SURFACE, A PLURALITY OF SYMMETRICALLY DISPOSED THIN RIBS EXTRUDED AXIALLY FROM AND PROJECTING AXIALLY BEYOND SAID SURFACE AND RESPECTIVELY PRESENTING POINTS CLOSELY ADJACENT TO AND OFFSET OPPOSITELY FROM A LONGITUDINAL AXIS OF SAID SHANK AND FORGED CUTTING EDGES EXTENDING GENERALLY RADIALLY AND AXIALLY REARWARDLY FROM SAID POINTS, SAID RIBS AND SAID CUTTING EDGES RESPECTIVELY EXTENDING GENERALLY PARALLEL TO AND SUBSTANTIALLY ON OPPOSITE SIDES OF A FIRST PLANE CONTAINING SAID LONGITUDINAL AXIS OF THE SHANK AND TRAVERSING A SECOND PLANE PERPENDICULAR TO SAID FIRST PLANE AND CONTAINING SAID AXIS, SAID POINTS BEING DISPOSED AT OPPOSITE SIDES OF SAID SECOND PLANE, SAID ENTERING END PORTION BEING INTERRUPTED BETWEEN SAID POINTS FOR PROMOTING INDEPENDENT ENGAGEMENT OF THE POINTS WITH A WORK STRUCTURE AND THEREBY FACILITATE ENTRY OF THE SCREW INTO A WORKPIECE, SAID ENTERING END PORTION HAVING A PLURALITY OF FLUTE MEANS FORGED THEREIN AND RESPECTIVELY DEFINED BY FIRST SURFACES RESPECTIVELY FLUSH WITH SAID CUTTING EDGES AND EXTENDING REARWARDLY FROM SAID CUTTING EDGES, SAID SURFACES INTERSECTING THE PERIPHERY OF SAID ENTERING END PORTION AND PROVIDING SIDE EDGES AT SAID LAST MENTIONED INTERSECTIONS, AND SAID SHANK INCLUDING A PLURALITY OF HELICAL THREAD CONVOLUTIONS EXTENDING REARWARDLY FROM SAID ENTERING END PORTION.