LOOSENESS PREVENTING SCREW AND FASTENING METHOD BY THIS SCREW

摘要

PURPOSE: To provide a looseness preventing screw extremely effective on the generation of a loosening phenomenon and a slipping phenomenon. CONSTITUTION: A looseness preventing screw has a head 2 provided with a screw rotating groove or a rotating shape part so as to fasten parts 20, 22 to each other by the screwing action of a screw part 9 formed continuously from the head 2. Plural protruding parts 5 forming a tilt angleθ1 to the proceeding direction face of a thread fastening direction T specified by the bearing surface 4 of the head 2, forming a tilt angleθ2 on the opposite side in a proceeding direction L reverse to the thread fastening direction T and having the relation ofθ1<θ2 are integrally formed on the bearing surface 4.