| 摘要 |
PURPOSE: To limit the rotation of a stud and to prevent the undesired withdrawal of a fastener by mounting a non-circular part between a head which can be inserted through a slot and prevents the withdrawal by the rotation, and a threaded part on a point of a shank. CONSTITUTION: A head 5 is formed by the long faces 8, 9 and the circular faces 10, 11 in the direction perpendicular to a shaft 7 of a stud 2, and inserted into a slot 20 to prevent the withdrawal after its rotation. A threaded part 12 is formed on a point of a shank 6 continued from the head 5, and a non- circular part 13 is formed between the head 5 and the threaded part 12. This non-circular part 13 comprises the flat faces 14-17 and the circular faces 18, 19 at the corners, and prevents the rotation of more than 90 deg. after the insertion of the head. Accordingly the fastener can be easily mounted, and the undesired withdrawal can be prevented after a nut 4 is fastened. |
