A seatbelt pretensioning retractor assembly for use in a passenger vehicle is provided. The pretensioning assembly includes a tube in fluid communication with a gas generator and a driving element disposed therein that travels in a first direction in response to actuation of the gas generator. The driving element includes a polymer rod. A stopper is coupled to an end portion of the polymer rod. In one example, a seal member is disposed between the gas generator and the stopper. In another example, the tube has an opening that is adjacent to an exit to facilitate venting gas from the gas generator.

In a belt tensioner (10) for a seat belt comprising an elongate pressure reservoir (12), a piston (18) movably supported in the pressure reservoir (12) in the longitudinal direction to which piston pressurized fluid can be applied and which in this way can be moved in a tensioning direction (S), a mechanical thrust means (20) interacting with the piston, the thrust means interacting with a gearwheel (22) and driving the same in the case of restraint, and comprising a stop (24) on which the piston (18) abuts in the tensioning direction in a final position, it is provided that between the piston (18) and the thrust means (20) a spacer (30) in the form of a separate member is provided which is dimensioned such that in the final position of the piston (18) the thrust means (20) is urged past the stop (24) by said spacer. Furthermore there is provided a method of mounting a belt tensioner of this type.

The invention provides in a best tensioner (10), especially a rotary tensioner, for a seat belt comprising an elongate and preferably cylindrical pressure cylinder (129, a piston (18) movably supported in the pressure cylinder (12) in the longitudinal direction which is adapted to be pressurized with fluid under pressure and thus to be moved into a tensioning direction (S), a thrust means (20) interacting with the piston (18) and a stop (24) provided on the inside (38) of the pressure cylinder (12) to which the piston (18) can be adjacent in the tensioning direction (S) at an end position at which the piston (18) seals the pressure cylinder (12), that the stop (24) is made of a plastically deformable material and is plastically deformed by the piston (18) at the end position so that the piston is in sealing contact with the inside of the pressure cylinder (12).

A belt retractor for a safety belt, having a belt reel for winding or unwinding the safety belt, and a belt force limiting installation which comprises a first and second torsion bar for limiting belt force. The belt retractor has a free-wheeling transmission which operates depending on the rotation angle and which after activation of the belt force limiting installation initially leaves the second torsion bar so as to be inactive, while the first torsion bar for limiting belt force is already being twisted, and the free-wheeling transmission activates the second torsion bar as soon as the free-wheeling transmission has been rotated about a predefined maximum free-wheeling rotation angle.

[Object] To provide a seat belt retractor that is capable of generating a more stable load when restricting a load acting on the seat belt and when absorbing energy, and a seat belt apparatus including the same. [Solution] A seat belt retractor 3 includes a frame 11, a seat belt 4, a spool 12 that is rotatably supported by the frame 11 and that retracts the seat belt 4, a lock mechanism 60 that allows rotation of the spool 12 while not in operation and that prevents rotation of the spool 12 in a seat belt withdrawing direction while in operation, and an energy absorption mechanism 20 that restricts a load acting on the seat belt 4 and that absorbs energy of an occupant. In the seat belt retractor 3, the energy absorption mechanism 20 includes a first energy absorption member 21 that absorbs energy through a rotational difference between the spool 12 and the lock mechanism 60, a first energy transmission member 22 that is attached on one end side of the first energy absorption member 21, a second energy transmission member 23 that meshes with the first energy transmission member 22, and a second energy absorption member 24 that absorbs energy through a rotational difference between the second energy transmission member 23 and the spool 12.

The invention relates to a pressure unit (64) for pressurizing a belt shaft (12) in a seat belt system comprising a screw (66) for fastening the pressure unit (64) to a frame (18) of the seat belt system, the screw (66) including a screw head (68) and a screw shank (70), wherein the pressure unit (64) comprises a fastening portion (72) having a screw hole (74) for inserting the screw shank (70), wherein radial play is provided between the screw hole (74) and the screw shank (70) and the fastening portion (72) on the screw head side includes mounting arms (76) for axially fixing the screw (66) in a pre-assembly position. Moreover, the invention also comprises an end fitting (11) of a seat belt system comprising such pressure unit (64).

A webbing take-up device includes a spool, a lock base that restricts pull-out direction rotation of the spool in a vehicle emergency, and a linear energy absorbing wire that deforms so as to permit pull-out direction rotation of the spool at or above a force limiter load when the lock base has restricted pull-out direction rotation of the spool. The webbing take-up device further includes a housing with which the energy absorbing wire engages along a radial direction inside face of the housing, and a winder section provided at a radial direction inside of the housing. The winder section is capable of rotating together as a unit with the spool, and takes up the energy absorbing wire by being rotated. Moreover, a wire guide and a lever are provided between the winder section and the housing. The wire guide and the lever pinch and deform the energy absorbing wire.

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.

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.