| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to prevent falling of a cap from a fastener with a simple structure of a low cost having a good productivity.SOLUTION: A cap 9 is applied to a stationery structure part 1 in which structural materials 3, 3 are fixed to each other by a fastener 5, which is inserted into through holes 3a formed in the structural materials 3, 3 and a collar 7 fastened to a tip 5a of the fastener 5, and is mounted in the state such that the cap is not engaged with the tip 5a of the fastener 5 and the collar 7. An inner peripheral surface 9e of the cap 9 is provided with a filler engagement part 91 which has a female thread rotating about a center axis CL and engages with a cured filler 11. The filler engagement part 91 includes: a first spiral engagement part 91a which is formed in a region on the cap inner side of the inner peripheral surface 9e in the center axis CL direction; and a second spiral engagement part 91b which is formed in a region on a cap opening end 9a side in the center axis CL direction, has an inner diameter larger than that of the first spiral engagement part 91a, and of which a spiral direction is opposite to that of the first spiral engagement part 91a. |
