A seat belt retractor includes a belt shaft pivot-mounted in a retractor frame, wherein the belt shaft shows an at least two-part design with a first and a second part. A load limiting device includes at least two parts, which can be moved relative to each other and have teeth, with which they alternately engage and disengage. Each of the parts of the load limiting device is allocated to a different part of the belt shaft. A tensioning device is located on the second part of the belt shaft and, upon activation, abruptly drives the belt shaft in the winding direction. One of the parts of the load limiting device, via a transmission device, is connected in a rotationally-fixed manner to the second part of the belt shaft through the first part, which is a hollow shaft.

A 3-point seat belt system having a seat belt retractor (20) with a spool (32), the spool (32) having a locked mode of operation and a freewheeling mode of operation; a seat belt (411) characterized as having a known elongation rate under stress; a collapsible member (40) wrapped about a center portion of the spool (32) of the retractor (20), the member (40) having an initial diameter dl when unstressed and collapsible to a lesser diameter of d2 under stress. The method having the step of generating a retarding force on the occupant (404) in proportion to the degree by which the collapsible member (40) collapses.

A 3-point seat belt system having a seat belt retractor (20) with a spool (32), the spool (32) having a locked mode of operation and a freewheeling mode of operation; a seat belt (411) characterized as having a known elongation rate under stress; a collapsible member (40) wrapped about a center portion of the spool (32) of the retractor (20), the member (40) having an initial diameter dl when unstressed and collapsible to a lesser diameter of d2 under stress. The method having the step of generating a retarding force on the occupant (404) in proportion to the degree by which the collapsible member (40) collapses.

In a webbing retractor device, a compression coil spring is suspended between an engagement frame of a V-gear and an engagement surface of a locking base. As a result of the engagement frame being engaged with from an exposed portion side by the compression coil spring that is being held in a holding groove of the locking base so as to be exposed to the exposed portion side, the compression coil spring is suspended between the V-gear and the locking base. Because of this, the compression coil spring can be easily suspended between the V-gear and the locking base.

In a webbing retractor device, a compression coil spring is suspended between an engagement frame of a V-gear and an engagement surface of a locking base. As a result of the engagement frame being engaged with from an exposed portion side by the compression coil spring that is being held in a holding groove of the locking base so as to be exposed to the exposed portion side, the compression coil spring is suspended between the V-gear and the locking base. Because of this, the compression coil spring can be easily suspended between the V-gear and the locking base.

A serrated portion is formed on an outer peripheral portion of a lock base body of a lock base of a webbing take-up device. Furthermore, a flange portion is formed on the outer peripheral portion of the lock base body. The flange portion is disposed on a vehicle front side with respect to the serrated portion. Triangular grooves of the serrated portion are closed by the flange portion. When the lock base becomes displaced in a vehicle rearward direction and the flange portion comes into abutting contact with a leg plate of a frame, further displacement of the lock base in the vehicle rearward direction is blocked. Due to this, engagement between the serrated portion and ratchet teeth of a ratchet hole in the leg plate can be maintained.

A webbing take-up device includes a spool capable of taking-up webbing worn by an occupant, a V-gear capable of rotating accompanying rotation of the spool, a lock pawl that is operated to restrict rotation of the spool in a pull-out direction, and a W-pawl provided at the V-gear, that is displaced and causes the lock pawl to operate when the V-gear is rotated in the pull-out direction at a specific speed or greater. The webbing take-up device also includes a restricting body that is moved to a permitting position permitting displacement of the W-pawl when the V-gear is rotated in the pull-out direction, and that is moved to a restricting position enabling the W-pawl to abut when the V-gear is rotated in a take-up direction, restricting displacement of the W-pawl due to the W-pawl abutting, a contact angle with the W-pawl being set with 90 degrees or greater.

A webbing take-up device includes a spool capable of taking-up webbing worn by an occupant, a V-gear capable of rotating accompanying rotation of the spool, a lock pawl that is operated to restrict rotation of the spool in a pull-out direction, and a W-pawl provided at the V-gear, that is displaced and causes the lock pawl to operate when the V-gear is rotated in the pull-out direction at a specific speed or greater. The webbing take-up device also includes a restricting body that is moved to a permitting position permitting displacement of the W-pawl when the V-gear is rotated in the pull-out direction, and that is moved to a restricting position enabling the W-pawl to abut when the V-gear is rotated in a take-up direction, restricting displacement of the W-pawl due to the W-pawl abutting, a contact angle with the W-pawl being set with 90 degrees or greater.

A webbing winding device includes a spool, a sensor lever, and a solenoid. The sensor lever is displaceable between the first position and the second position. In a state where the sensor lever is disposed at the first position, the rotation in the drawing-out direction of the spool is enabled, and in a state where the sensor lever is disposed at the second position, the rotation in the drawing-out direction of the spool is locked. When the solenoid is actuated, a part of the sensor lever is attracted and the sensor lever is displaced from the first position to the second position. The center of gravity of the sensor lever is set so that the sensor lever is displaced toward the second position when negative acceleration with respect to the direction in which a part of the sensor lever is attracted to the solenoid is generated in the sensor lever.

A webbing winding device includes a spool, a sensor lever, and a solenoid. The sensor lever is displaceable between the first position and the second position. In a state where the sensor lever is disposed at the first position, the rotation in the drawing-out direction of the spool is enabled, and in a state where the sensor lever is disposed at the second position, the rotation in the drawing-out direction of the spool is locked. When the solenoid is actuated, a part of the sensor lever is attracted and the sensor lever is displaced from the first position to the second position. The center of gravity of the sensor lever is set so that the sensor lever is displaced toward the second position when negative acceleration with respect to the direction in which a part of the sensor lever is attracted to the solenoid is generated in the sensor lever.