Taper implant and a screw-fastening structure using a taper implant with female threads

The present invention relates to a taper implant, a screw-fastening structure using a taper implant with female threads, a forming drill for drilling an insertion hole for the taper implant, and a hammer for driving the taper implant. A method of fastening a first member and a second member using a taper implant having a threaded hole therein includes providing a taper implant having a frusto-conical outer surface, a projecting portion connected to a larger diameter end and a threaded hole passing therethrough and providing a first member having a wall portion with a tapered hole extending therethrough and having a counterbored portion adjacent a larger diameter end to receive the projection portion of the taper implant. The taper implant is inserted into the hole of the first member and held therein by frictional contact. A second member is provided having a wall portion with a hole therethrough. The second member is positioned in contact with the first member and the two members are fastened together by inserting a male screw through the hole of the second member and threading the male screw into engagement with the threaded hole of the taper implant.