A webbing take-up device in which, when a pretensioner mechanism is activated and turning of a pinion relative to a spool is allowed, a lock pawl is turned by the pinion and a trigger wire is sheared by the lock pawl. Thereafter, the pinion turns more relative to the lock pawl and shears a lock pin of the lock pawl. Hence, the lock pawl turns and activates an activation mechanism. Therefore, the activation mechanism may be activated without a torsion shaft of a force limiter mechanism allowing turning of a lock base in the take-up direction relative to the spool.

The invention relates to an actuator (70) for releasing a load limiter (14) of a belt retractor for a vehicle seat belt, comprising a case (72) which is adapted to be attached to a frame (10) of the belt retractor and includes a seat (82) in which a pyrotechnical actor (80) is arranged, characterized in that a retaining clip (90) for locking the actor (80) within the seat (82) is attached to the case (72). The invention further relates to a belt retractor comprising a frame (10), a belt reel (12) rotatably supported in the frame, a load limiter (14) which is detachably connected to the belt reel (12) and an actuator (70) of the afore-mentioned type, characterized in that the retaining clip (90) bears on the frame (10).

Provided are a seat belt retractor and a seat belt device with which it is possible to improve an occupant-restraining property and energy absorption characteristics. A seat belt retractor 1 including a spool 2 that winds up a webbing W for restraining an occupant, a shaft 3 inserted through an axial center of the spool 2, and a locking base 4 connected to the shaft 3 and capable of switching between a rotating state and a non-rotating state, further includes an energy absorption device 5 capable of changing an energy absorption amount according to a relative rotation speed between the spool 2 and the shaft 3, and a load adjustment member 6 that blocks or reduces load transmission when a load equal to or greater than a threshold is applied to the shaft 3 or the spool 2. The spool 2, the shaft 3, the locking base 4, the energy absorption device 5, and the load adjustment member 6 are serially connected.

In a vehicle emergency, rotation of a lock base in a pull-out direction opposite to a take-up direction is restricted. A first pinion-configuring portion formed at an outer circumferential portion of the lock base configures one width direction side of a pinion section that is rotated in the take-up direction by a rack that moves due to fluid pressure in a vehicle emergency. A coupling member disposed between the lock base and the torsion shaft is fixed to the lock base and to a torsion shaft. A second pinion-configuring portion that configures a width direction other side of the pinion section is formed alongside the first pinion-configuring portion at an outer circumferential portion of the coupling member.

A safety belt retractor, a vehicle safety belt with the safety belt retractor and a vehicle with the vehicle safety belt are provided. The safety belt retractor is provided, on an end segment thereof, with a pre-tensioning, force-limiting and decoupling device that comprises a safety belt reel (1), a driving element (2), a sleeve (3) and an energy absorbing disc (4). The safety belt reel (1) is provided with a first recess (10) and a second recess. A first helical surface (9) is arranged in the first recess (10), and the driving element (2) is provided with a first projection (21) having a second helical surface acting together with the first helical surface (9). The sleeve (3) is provided with a second projection (31) mounted in the second recess. Under a predetermined load, the second projection (31) is cut off, such that the energy absorbing disc (4) is plastically deformed due to squeezing. The safety belt retractor achieves on the same end segment, the pre-tensioning, force-limiting and decoupling functions as well as a compact structure.

A switching mechanism (100) in a force limiter mechanism of a seat belt retractor including: a locking mechanism including a locking element (68) that locks a torque tube (64) with respect to a spindle (61) so that the torque tube (64) rotates together with the spindle (61) and a spindle ring (70); a switch ring (120) rotatable to unlock the locking mechanism; and a switch housing (101) that stores the switch ring (120), a switch piston (115) adapted to activate the switch ring (120). A switching gas generator (116) generates gas for pushing out the switch piston (115) upon activation of the switching mechanism. The switch housing (101) of the switching mechanism (100) has a protrusion (110) that protrudes in an incoming direction of an operated part (122) at an abutment part hit by the switch ring (120) rotated by the switch piston (115) to control movement of the switch ring.

Provided are a seat belt retractor and a seat belt device with which it is possible to improve energy absorption characteristics and a restraining property. The seat belt retractor includes a spool that performs winding of a webbing for restraining an occupant, a shaft inserted through an axial center of the spool, and a locking base connected to the shaft and capable of switching between a rotating state and a non-rotating state. The seat belt retractor further includes a load adjustment member disposed between the shaft and the locking base and that blocks or reduces load transmission in a case where a load equal to or greater than a threshold is applied to the shaft, and an energy absorption device disposed between the spool and the locking base and capable of changing an energy absorption amount according to a relative rotation speed between the spool and the locking base. The energy absorption device is connected in parallel with the load adjustment member.

A seatbelt retractor includes a base, a spool, a cylinder, a transfer plate, and a cylinder lock. The spool is rotatably coupled to the base and has a piston portion. The cylinder is engaged with the piston portion and therewith defines a chamber. The piston portion is movable from a first position to a second position. The transfer plate is translateably disposed in the first chamber. The cylinder lock in a first condition rotatably fixes the cylinder to the base. Damping fluid is in the chamber.

In a webbing take-up device, in a vehicle collision, pull-out of a webbing from a spool by an occupant is limited by a torsion shaft of a first force limiter mechanism, is limited by a wire of a second force limiter mechanism in correspondence with a build of an occupant, and is limited by a wire of a third force limiter mechanism in correspondence with a deceleration rate of the vehicle. This enables a load at which to limit the webbing from being pulled out from the spool in a vehicle collision to be a load suited to the build of the occupant and the deceleration rate of the vehicle.

A seatbelt retractor for a seat belt device in a vehicle. The retractor includes a frame and a spool configured to be fixed to one end of a seat belt webbing so that the webbing may be wound around the spool. The spool is rotatably mounted at both ends to the frame and configured to rotate in a webbing extraction direction and a webbing retraction direction. The retractor includes primary and secondary torsion bars positioned end to end in the spool along an axis of rotation of the spool. The primary and secondary torsion bars are configured to be locked at second ends of the torsion bars opposite to the first end. The first ends of the torsion bars are configured to rotate relative to the second ends so that the primary and secondary torsion bars deform to absorb force when a vehicle acceleration exceeds a predetermined value.