Patent ID: 8827196

Claim:
A seatbelt retractor for removing a slack in a webbing, the seatbelt retractor comprising: a take-up drum; a ratchet gear formed at a periphery of an edge portion of the take-up drum onto which the webbing is wound; a pawl configured to engage the ratchet gear in response to a predetermined acceleration of a vehicle speed or an acceleration of a webbing-pull-out speed; a pretensioner assembly configured to rotate the take-up drum in a retracting direction to retract the webbing if a vehicle collision occurs; and a housing which includes a first wall portion and a second wall portion facing the first wall portion and houses the take-up drum, wherein: the pretensioner assembly includes: a driving device mounted to an outside surface of the first wall portion of the housing and configured to cause the take-up drum to rotate in the retracting direction of the webbing if a vehicle collision occurs; and a locking device which is directly activated by the driving device upon activation of the driving device and locks the pawl in an engaged state with the ratchet gear, the ratchet gear is formed on the periphery of the edge portion of the take-up drum so as to face an inside of the second wall portion of the housing, the pawl is provided at a position where the pawl is disengaged from the ratchet gear while one end of the pawl is mounted directly on and in contact with the inside of the second wall portion of the housing in a rotatable mariner, the locking device comprises: an arm member of which one end is rotatably supported at the outside of the first wall portion of the housing; a rotating device which is provided at the outside of the first wall portion of the housing and is directly activated by the driving device so as to cause the arm member to rotate in a predetermined direction; a depressing member which is formed separately from the pawl and arranged in contact with a side face of the pawl at an opposite side with respect to the ratchet gear while one end of the depressing member is rotatably supported at the inside of the second wall portion of the housing; and a coupling shaft which couples the arm member and the depressing member, and wherein, if the driving device is activated, the arm member is rotated in the predetermined direction by the rotating device, thereby the depressing member is rotated towards the ratchet gear by the coupling shaft that is connected to the arm member and the pawl is rotated toward the ratchet gear by the depressing member and caused to engage the ratchet gear.