Patent ID: 7650675

Claim:
A buckle having a plug and a socket connected to each other in a predetermined connecting direction, wherein the plug includes a plug body, a tongue-like portion extending from the plug body, and a first projected portion projecting from the tongue-like portion and having a first locked face formed thereon, the first locked face crossing the connecting direction; the socket includes a socket body, an insertion hole provided in the socket body and into which the tongue-like portion is inserted, and a first stepped portion provided at the insertion hole and having a first locking face formed thereon, the first locking face crossing the connecting direction and engaging with the first locked face; the buckle comprising: a second projected portion projecting from the tongue-like portion and having a second locked face formed thereon, the second locked face crossing the connecting direction; and a second stepped portion provided at the insertion hole and having a second locking face formed thereon, the second locking face crossing the connecting direction and engaging with the second locked face, wherein either of the first and second locked faces and the first and second locking faces are concave as extending from the plug toward the socket and are in a curved surface shape having the same center, the other of the first and second locked faces and the first and second locking faces are convex as extending from the plug toward the socket and are in a curved surface shape having the same center, and the first locked face and the first locking face have substantially the same curvature, and the second locked face and the second locking face have substantially the same curvature.