Tensioner drive for a safety belt device that includes a gas generator, a driving wheel, and a feed tube. The tube connects the gas generator and the driving wheel. There is at least one thrust body in the feed tube. The thrust body is accelerated after triggering of the gas generator and drives the driving wheel. There is a fixing element between the thrust body and the gas generator that is supported on the inner wall of the feed tube.

A seatbelt retractor includes a base, a spool, a cylinder, a sleeve and a cylinder lock. The spool is rotatably coupled to the base and has a piston portion. A smaller initialization piston extends from the piston portion. The cylinder is engaged with the piston portion and therewith defines a first chamber. The sleeve is within the cylinder and receives the initialization piston. The sleeve and the initialization piston define an initialization chamber. The cylinder lock in a first condition rotatably fixes the cylinder to the base. Damping fluid is disposed in the chamber.

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.

A seat belt retractor includes a housing including a first side wall and a second side wall facing each other, a winding drum configured to wind up a webbing, a locking base, a torsion bar including one end side, which is opposite to the locking base, coupled to the winding drum without being rotatable relative to the winding drum, and the other end side coupled to the locking base without being rotatable relative to the locking base, a pretensioner including: a pretensioner casing attached to the first side wall; and a drive wheel attached to the locking base, a lock member located in the locking base, and a stopper member being screwed onto a male screw of the locking base.

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 tensioner for a seat belt system comprises a pinion (10) pivoted about an axis of rotation A which is adapted to be coupled to a best reel of a belt retractor, a drive unit, a force transmission element (12) and a guide means. By activating the drive unit the force transmission element (12) is moved along the guide means so that it engages in the pinion (10). The guide means includes a portion (16) which is deformable in a direction x perpendicular to the axis of rotation A of the pinion (10) and to the direction of movement y of the force transmission element (12).

A pretensioner includes a drive wheel provided with a plurality of engaging teeth for rotating a spool, the spool for winding up a webbing for fastening a passenger; and an elongated resin component that transmits power to the drive wheel during an emergency, wherein the plurality of teeth is positioned such that, when one engaging tooth is caused to contact a tip of the elongated resin component in an approximately planer manner, another engaging tooth adjacent to the one engaging tooth in a direction opposite to a rotation direction can contact a side surface of the elongated resin component.

A pretensioner and safety belt assembly may include includes a base member fixed to a vehicle, a torsion shaft having a first side and a second side rotatably supported on the base member, a torsion tube having a first end portion fixed on an external surface of the torsion shaft and a second end portion rotatably supported on the external surface of the torsion shaft wherein a belt configured to restrain an occupant is wound around an external surface of the torsion tube, a traction wire wound around an end portion of the torsion shaft on an opposite side to where the torsion tube is fixed to the torsion shaft in an opposite direction to a direction in which the belt is wound, and a pulling device configured to pull the traction wire to rotate the torsion shaft.

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.