Sealing device for watch crown

A sealing device (1) designed to be positioned on a watch crown (5), arranged on two shoulders (14,20) protecting said crown (5) of a watchcase (8), the device (1) comprising, on the one hand, a cover (2) possessing an annular part (3) that fits and rests on the periphery of a cabochon (4) of the crown (5) against a seal (6), said cover (2) including at its end a closure lug (9) and pivoting on a first axis (7) located on one of the shoulders (20) protecting the crown (5), the sealing device (1) including, on the other hand, a buckle (10) for the closure of the cover (2), characterized in that said buckle (10) pivots on a second axis (11) located on a fastening arm (12), said fastening arm (12) pivoting on a third axis (13) and located on the other shoulder (14) protecting the crown (5) of the watchcase (8) such that the device (1) is in the closed position when, on the one hand, said buckle (10) and the cover (2) are, respectively, positioned on the lug (9) and the periphery of said cabochon (4), and, on the other hand, the fastening arm (12) is arranged against the watchcase (8), the device (1) being in the open position when the end of the fastening arm (12) and the buckle (10) are, respectively, detached from the watchcase (8) and the closure lug (9), enabling the cover (2) to be disengaged from the crown (5) of the watchcase (8).