Patent ID: 7735766

Claim:
A seatbelt retractor comprising: a spool for withdrawably retracting a seatbelt; a motor that generates a torque for rotating the spool in a belt retracting direction and a belt withdrawing direction; a reduction mechanism that connects the spool and the motor with each other to transmit the rotation of the motor, the seatbelt retractor driving the rotation of the motor in the belt withdrawing direction as the seatbelt is withdrawn; and a spool and motor disconnecting mechanism that temporarily disconnects the connection between the spool and the motor when the seatbelt is withdrawn, wherein the spool and motor disconnecting mechanism includes an internal-gear-rotation enabling mechanism that allows an internal gear to temporarily rotate in the belt withdrawing direction by a predetermined amount and to stop the internal gear from rotating in the belt withdrawing direction by an amount exceeding the predetermined amount when the seatbelt is withdrawn, wherein the spool and the reduction mechanism are supported by a frame, wherein the internal-gear-rotation enabling mechanism includes an arc-shaped frame-side stopper provided on the frame and first and second arc-shaped internal-gear-side stoppers, at least one of the arc-shaped internal-gear-side stoppers comes into contact with the arc-shaped frame-side stopper when the internal gear rotates in the belt withdrawing direction by the predetermined amount to thereby stop the rotation of the internal gear in the belt withdrawing direction, and the arc-shaped frame-side stopper being separated from the first and second arc-shaped internal-gear-side stoppers by first and second springs, one spring on each side of the arc-shaped frame-side stopper.