| 摘要 |
PROBLEM TO BE SOLVED: To provide a self-tapping screw capable of carrying out positive tapping even with respect to a hard base such as concrete. SOLUTION: The self-tapping screw 11 made of anticorrosion metal material is provided with a thread 14 formed throughout at least one part of an outer circumference of a shaft 12. A cutting means 16 is arranged in a recess 15 of the thread 14. The cutting means is harder than the thread 14. The cutting means 16 is composed of a welding material fixed in the recess 15 by laser welding. COPYRIGHT: (C)2006,JPO&NCIPI
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