A webbing take-up device includes a spool, a lock gear that restricts pull-out direction rotation of the spool, a force limiter mechanism that permits pull-out direction rotation of the spool at or above a force limiter load, and a pawl that switches the force limiter load. The webbing take-up device further includes a cylinder section that includes a first cylindrical portion and a second cylindrical portion, a gas generator that supplies gas into the second cylindrical portion, and a piston section that is moved along the first cylindrical portion by an increase in pressure inside the second cylindrical portion and the first cylindrical portion so as to press and displace the pawl. An axial center of the second cylindrical portion is disposed offset with respect to an axial center of the first cylindrical portion, and an abutted portion that is abutted by the piston section is provided at a boundary between the first cylindrical portion and the second cylindrical portion.

The occupant restraining device for a vehicle has a seatbelt, a collision predicting sensor, a braking device that enlarges a gap between a vehicle occupant and a seatback of a vehicle seat, an explosive-type pretensioner and electric motor that retract the seatbelt, and a control section that, in a case in which a front collision of the vehicle is sensed in advance by the collision predicting sensor, enlarges the gap between the vehicle occupant and the seatback by the braking device and starts retracting of the seatbelt by the explosive-type pretensioner and the electric motor, and at least until forward movement of the vehicle occupant starts after occurrence of the front collision, continues to input load to the vehicle occupant from the seatbelt and continues to move the vehicle occupant toward a vehicle rear side.

A seat belt retractor includes a housing including a pair of side walls facing each other, a winding drum configured to wind up a webbing, a locking base prevented from being rotated in the pull-out direction, in an emergency of a vehicle, an impact energy absorbing member including a first end side coupled to the winding drum and a second end side coupled to the locking base, the impact energy absorbing member connecting the winding drum and the locking base so as to be integrally rotatable, in a normal state, at least one impact energy absorbing wire housed in at least one slot that is provided in the winding drum, and a stopper member configured to define an allowable amount of relative rotation between the winding drum and the locking base in a case where the impact energy absorbing member absorbs the impact energy.

A gas generator includes a substantially cylindrical cup with bottom where a gas generating agent is accommodated, the cup including one axial end as an opening end, and a substantially columnar holder to which the cup is coaxially assembled to close the opening end, the holder holding an igniter such that an ignition portion faces the gas generating agent. An annular step portion is provided at a periphery of an axial end of the holder on a side facing the cup. The cup is fixed to the holder by fitting the opening end to the annular step portion and providing an annular welded portion at the opening end, the annular welded portion being joined to the annular step portion so as to extend along a circumferential direction of the cup.

A pretensioner includes a driving wheel and a power transmission unit. A spool is rotatably disposed in the driving wheel. The spool winds a webbing. The power transmission unit transmits power to the driving wheel. The power transmission unit includes a resin-made long body and a passage of the resin-made long body. The resin-made long body rotates the driving wheel. The passage is formed in an outer circumference of the driving wheel. The passage includes a wall surface, a cover member and a stopper. The wall surface is disposed on one side surface of the driving wheel. The cover member is fixed in the wall surface from the other side surface of the driving wheel. The stopper stops a tip portion of the resin-made long body which has rotated the driving wheel. The stopper is configured by a fastening member connecting the cover member and the wall surface.

In a belt retractor (10) having a belt tensioner (16) and a force-limiting device, the belt tensioner (16) includes a pivoted pinion gear (24) associated with a belt reel (14), a drive unit (18) and an oblong force-transmitting element (22) movable by the drive unit (18) supported at least partly in a tubular portion (21) and adapted to be engaged in the pinion gear (24) so as to rotate the pinion gear (24) in a tensioning direction (A). The force-transmitting element (22) includes a bending portion (30) which is provided at the rear end of the force-transmitting element (22) viewed in the tensioning direction and which is designed to be pressure-resistant in the longitudinal direction (L) of the force-transmitting element (22) but to be flexible in a direction perpendicular to the longitudinal direction (L).

A belt tensioner for a belt retractor having a load limiter includes a pivoted pinion (14) coupled to a belt reel, a drive unit and a load transmission element (20) moved by the drive unit. The load transmission element (20) engages in the pinion (14) so as to rotate the pinion in a tensioning direction A. The load transmission element (20) is designed so that in the rotational position adopted by the pinion (14) after being rotated by the load transmission element (20) a part (20b) of the load transmission element (20) engages in the pinion (14). A method of tensioning a seat belt by means of a belt tensioner and subsequent load limitation by means of a load limiter includes moving a load transmission element (20) by a drive unit in a first direction so that the load transmission element (20) engages in a pinion (14) coupled to a belt reel (12). The rotating the pinion (14) is rotated by the moved load transmission element (20) in a tensioning direction A. When the rotation of the pinion (14) is completed it is ensured that a part (20b) of the load transmission element (20) engages in the pinion (14).

A pretensioner includes a driving wheel and a power transmission unit. A spool is disposed to be rotatable in the driving wheel. The spool winds a webbing which restrains an occupant. The power transmission unit transmits power to the driving wheel during an emergency. The power transmission unit includes a resin-made long body, a pipe and a gas generator. The resin-made long body rotates the driving wheel. The pipe contains the resin-made long body. The gas generator supplies an operation gas into the pipe. The resin-made long body discharged from the pipe is configured to rotate the driving wheel while the resin-made long body is wound around the driving wheel.

A pretensioner for introducing a webbing wound in a spool by explosive power obtained by exploding gunpowder when an impact is applied from the outside, the pretensioner includes: a hollow cylinder having one side surface for inserting a portion of a pinion connected to the spool; a micro gas generator (MGG) mounted in an upper end portion of the cylinder and for transferring explosive power into the cylinder while gunpowder provided at the inside explodes when an impact is applied from the outside; a rack mounted in a length direction at the inside of the cylinder and having one end portion disposed toward the MGG and having the other end portion disposed opposite to the pinion and having gear teeth provided in one side surface separated not to engage with the pinion before receiving explosive power from the MGG; and a roller for receiving explosive power from the MGG and rotatably mounted at the other side surface opposite to one side surface of the cylinder in which a portion of the pinion is inserted so that the gear teeth of the rack engage with the pinion when the rack falls toward a lower end portion of the cylinder and for guiding the separated rack to move toward the pinion.

A seatbelt pretensioner system includes a pretensioner tube in fluid communication with a gas generator and a pretensioner rod having a proximal end portion disposed toward the gas generator and a distal end portion disposed at an exit of the pretensioner tube. The pretensioner rod is disposed inside the pretensioner tube in a pre-actuation state and adapted to travel within the pretensioner tube toward a pretensioner wheel upon an actuation of the gas generator in a post-actuation state. The pretensioner rod includes a protrusion formed in a radial direction of the rod to couple with the pretensioner tube to restrict the rod from moving out from the pretensioner tube in the pre-actuation state. The pretensioner rod is configured to avoid the stripping of the rod and reduce energy consumption when the polymer rod is deformed during pretensioning.