Patent ID: 8632289

Claim:
A tapping screw comprising: a cylindrical portion; a head disposed on one end of the cylindrical portion; a conical portion disposed on an opposite end of the cylindrical portion, and an end of the conical portion forming a tip of the tapping screw; a thread of a parallel screw portion disposed on the cylindrical portion, and a thread of a tapered screw portion disposed on the conical portion, wherein the thread of the tapered screw portion extends to the tip of the tapping screw, and the thread of the parallel screw portion is connected to, and continuous with, the thread of the tapered screw portion; a second thread extending in parallel with the thread of the tapered screw portion, wherein the second thread extends to the tip of the tapping screw, the second thread and the thread of the tapered screw portion form a double-start thread along the tapered screw portion, and the double-start thread is disposed only on the conical portion.