| 主权项 |
1. A seatbelt retractor comprising:
a take-up drum onto which a webbing is wound; a lock mechanism having a lock member that is arranged near one end of the take-up drum and connected to the take-up drum with relative rotation between the take-up drum and the lock member being prohibited, the lock member being prohibited from rotating in a webbing-pull-out direction in case of emergency, and the take-up drum being allowed a relative rotation with respect to the lock member when force to pull out the webbing exceeds a predetermined value in a state that the lock member is prohibited from rotating in the webbing-pull-out direction; an energy absorption mechanism arranged between the take-up drum and the lock member and configured to absorb energy by allowing the relative rotation between the take-up drum and the lock member; and a stopper mechanism configured to stop the relative rotation between the take-up drum and the lock member when the take-up drum is rotated at a predetermined number of times relative to the locking member, wherein the lock member includes:
a closed cylindrical portion having lock teeth; anda fixation boss provided inside of the closed cylindrical portion and inserted in a fitting hole formed at the one end of the take-up drum and facing to the take-up drum along an axial direction of the closed cylindrical portion, wherein the stopper mechanism includes a ring member of which inner peripheral surface is mounted on the fixation boss and of which outer peripheral surface is fitted in the fitting hole so as to prohibit relative rotation with respect to the fitting hole, the ring member being movable relative to the fixation boss in the axial direction of the take-up drum by the relative rotation with respect to the fixation boss, and wherein movable area allowed for the ring member to move on the fixation boss axially outward with respect to the take-up drum has an movable end located inside of the closed cylindrical portion. |
