To provide a fastener which is excellent in an aesthetic appearance and in operatability when engaging a first plate member and a second plate member or releasing the engagement and a wristwatch.
A middle fastener 5 has a middle plate 51, a lower plate 52 turnably supported by the middle plate 51, and a holding mechanism 6 for holding a folded state of the middle plate 51 and the lower plate 52; the holding mechanism 6 has a middle fastener body 7 arranged in the middle plate 51, a first engaging part 10 arranged in the middle fastener body 7 and having a detent 113, an engaging member 8 turnably supported to the lower plate 52 and having a detent 81, and a torsion spring 9 for anticlockwise biasing the engaging member 8. The middle fastener 5 can assume an engaging state in which the detent 113 of the first engaging part 10 and the detent 81 of the engaging member 8 engage with each other and a releasing state in which the engaging state is released by operating the middle fastener body 7.
| WO/2018/053533 | TENSION RELEASE FASTENER |
| JPH08336406 | BAND FOR WRIST WATCH |
Osamu Suzawa
Kazuhiko Miyasaka