US Patent 7090452 Tapping screw

A tapping screw includes a head, a shank and a cutting member, Said the shank has male threads, and the cutting member extends down from the shank and has a plurality of cutting grooves lengthwise formed and/or a plurality of wings also lengthwise formed; an annular groove is further provided between the shank and the cutting groove for wood waste cut out of a drilled hole of an object to move out smoothly and quickly, so the sharpness of the cutting member and the pointed end may be kept usual, and resistance against drilling and fixing of the screw may be reduced.