An increase in structural complexity is suppressed in a webbing take-up device provided with a force limiter load switching mechanism and a pre-tensioner mechanism. The webbing take-up device includes a spool that takes up a webbing, a pre-tensioner mechanism that takes up the webbing onto the spool by rotating the spool in the take-up direction in a vehicle emergency, and a lock mechanism that restricts pull-out direction rotation of the spool in a vehicle emergency. The webbing take-up device further includes a force limiter mechanism that permits pull-out direction rotation of the spool at a force limiter load or greater when the lock mechanism has restricted pull-out direction rotation of the spool, and a force limiter load switching mechanism that switches a force limiter load value by being input with a portion of an actuation force that actuates the pre-tensioner mechanism.

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.

A belt retractor having a belt reel, a safety belt which can be wound thereon to form a wound belt, a pyrotechnic belt tensioner having a drive device which is guided in a tube and can be driven to perform a drive movement, and at least one first further assembly arranged coaxially to the rotational axis of the belt reel and in series with the belt reel, a safety belt which can be wound thereon to form a wound belt, and at least one first assembly, wherein the tube has a straight linear section which extends parallel to the rotational axis of the belt reel and the longitudinal axis of the assembly and is arranged on the side of the belt reel.

In the method for mounting an inflator (12) within a tube (14), especially of a belt tensioner, wherein an end portion (28) of the tube (14) is formed radially inwardly so that a first contact surface (30) directed to the interior of the tube (14) occurs, prior to forming an annular stabilizing disk (34) is arranged between the first contact surface (30) and a second contact surface (32) configured at the inflator (12).

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.

A pretensioner apparatus of a seat belt may include a movement tube, a piston movably disposed inside the movement tube, a gas generator fluid-connected to the movement tube and generating a gas upon crash of the vehicle so as to inject the gas into the movement tube to move the piston in a predetermined direction, a linkage unit, a worm connected to the piston through the linkage unit, and a worm wheel engaged with the worm, wherein the worm rotates according to movement of the piston via the linkage unit when the piston moves in the predetermined direction by the gas generated by the gas generator, and wherein the worm wheel fixed to a spool rotates together with the worm to rotate the spool and a seat belt webbing connected to the spool is wound around the spool while the worm rotates according to the movement of the piston.

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 pretensioner having a fracture connection-type rack gear includes: a housing having a receiving space; a pinion gear provided in the receiving space, connected to a rotating shaft of a spool around which a webbing of a seat belt is wound, and rotated by rotation of the spool; a micro gas generator generating explosive power by impact from the outside; a conveying pipe having one side connected with the micro gas generator and the other side having an opening and connected to the receiving space; ball members provided in the conveying pipe, and conveyed toward the receiving space by the explosive power; and a rack gear provided to be fixed into the receiving space by a fixing unit, meshing with the pinion gear when the fixing unit is fractured, and rotating the pinion gear, by residual thrust of the ball members, in a direction in which the webbing is retracted.

In a pretensioner mechanism of a webbing take-up device, a sealing member seals a communicating hole of a piston. When a force limiter mechanism is operated and rotating of a spool in a pull-out direction is allowed, the piston is moved to an upper side in a state in which the sealing member is pressed and contacted against a cylinder. As a result, the sealing member is turned and the sealing of the communicating hole by the sealing member is released. In consequence, a number of components may be reduced and assembly characteristics of the pretensioner mechanism may be improved.

An end fitting tensioner (10) for a seat belt system includes a rotatable belt shaft (12) to which one end (14) of a webbing (16) is fixed, a belt shaft housing (18) in which the belt shaft (12) is supported, a rope reel (36) which is arranged at an axial end of the belt shaft (12) and is connected to the belt shaft (12) in a rotationally fixed manner, as well as a pull rope (41) which is secured by one rope end (45) on the rope reel (36) and can at least partly be wound onto the rope reel (36). The rope reel (36) includes a winding surface (62) for the pull rope (41) that is conically tapered in the axial direction.