THREADED BOLT AND MANUFACTURING METHOD OF THE SAME

PROBLEM TO BE SOLVED: To provide a usable threaded bolt which can be screwed without a risk of damaging a thread, which tends to cause no clogging on a lacquer painted surface, and which is inexpensively manufactured, in particular. SOLUTION: The threaded bolt 1 comprises a basically cylindrical shank having a root end 3 and a head end 4. Herein, a spiral male screw 11 is threaded which has at least one main screw section 12 and at least one introduction screw section 13 adjacent to the main screw section 12 near the root end 3. The introduction screw section 13 has an introduction face different from the main screw section 12, and it is formed to engage with the screw section of a female screw as a complementary element without crossing it. To form an empty space to store lacquer residuals, the introduction screw section 13 and the main screw section 12 are interrupted from each other with at least one groove 15 extending in the longitudinal direction of the shank 2. The screw sections 12, 13 and the groove 15 are first formed with rolling work. COPYRIGHT: (C)2009,JPO&INPIT