Seat belt retractor

A seat belt retractor comprising:

• a housing including a pair of side walls facing each other;
• a winding drum configured to wind up a webbing, the winding drum being housed between the pair of side walls so as to be rotatable in a winding direction and a pull-out direction of the webbing;
• a locking base configured to rotate together with the winding drum in a normal state and to be prevented from being rotated in the pull-out direction in an emergency of a vehicle;
• and
• a pretensioner configured to rotate the winding drum in the winding direction in the emergency, wherein
• the pretensioner includes
• a drive wheel provided on one end side of the winding drum, the drive wheel being configured to rotate in the winding direction together with the winding drum at least at an initial stage in the emergency,
• a tubular pressure container provided to the side wall on the pretensioner side, of the pair of side walls, the pressure container including a terminal end portion opened at a position adjacent to the drive wheel and a base end portion provided with a gas generator, and
• a moving member housed in the pressure container in a normal state, the moving member being configured to, in the emergency, be engaged with the drive wheel while being pushed out in an opening direction of the terminal end portion from the pressure container by gas generated from the gas generator, so as to rotate the drive wheel in the winding direction,
• the pressure container is provided such that the opening direction of the terminal end portion is tilted toward the winding drum or opposite to the winding drum, with respect to a plane orthogonal to an axial direction of the winding drum, and
• when the pretensioner is activated, the moving member moves the locking base, the drive wheel, and the winding drum to the opening direction side of the terminal end portion of the pressure container in the axial direction of the winding drum, and brings one of the locking base, the drive wheel, and the winding drum into contact with a restricting member that is a part of the housing or that is attached to the housing.