A webbing take-up device is obtained in which the number of rotations of a spool from the start of deformation of a first energy absorption member until the start of deformation of a second energy absorption member can exceed one rotation. In a webbing take-up device, a restricting tab is provided at an open side of the engagement recess portion. Although the leading end of the stopper pawl and the engagement recess portion face each other in the first rotation of the lock ring, a leading end of a stopper pawl is thereby unable to enter inside the engagement recess portion. The restricting tab is restricted from rotating when the leading end of the stopper pawl abuts an abutting portion of the restricting tab. When the lock ring accordingly rotates in a pull-out direction, the restricting tab moves relative to the open side of the engagement recess portion. When the leading end of the stopper pawl and the engagement recess portion face each other in this state, the leading end of the stopper pawl is thereby able to enter the engagement recess portion.

A seat belt retractor comprises a rotatable spool on which seat belt webbing is wound. The spool is rotatable in a webbing withdrawal direction and an opposite webbing retraction direction. The seat belt retractor also comprises a pretensioner actuatable to rotate the spool in the webbing retraction direction and a load-limiting system to limit a load applied to a vehicle occupant by the seat belt webbing. The load-limiting system includes a torsion bar mounted such that the torsion bar is twisted when a load in excess of a predetermined load is applied to the spool in the webbing withdrawal direction by the seat belt webbing. The bad-limiting system also includes a stop assembly actuatable to limit rotation of the spool in the webbing withdrawal direction to a predetermined number of rotations while the torsion bar is being twisted. The stop assembly is actuated upon actuation of the pretensioner.

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.

The present disclosure presents a webbing take-up device, which comprises: a spool; a lock section that is restricted from rotating at a time of a vehicle emergency so as to limit rotation of the spool in the pull-out direction; a force limiter mechanism that permits rotation of the spool in the pull-out direction at a force limiter load or greater when rotation of the spool in the pull-out direction with respect to the lock section is being limited; a switching member that switches a load value of the force limiter load by switching between a rotation-restricted state and a rotation-enabled state; and a mounting member that includes a switching member mounting section at which the switching member is disposed, and a restriction section that is engaged with the switching member so as to restrict displacement of the switching member disposed at the switching member mounting section.

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.

A safety belt retractor, comprising a frame (8) and a belt retracting cylinder (1), the retracting cylinder (1) being rotatably supported in the frame (8) and being composed to be used for winding a woven belt (2). The frame (8) comprises: a back plate (8h), which has a first side and a second side which are opposite to each other, and a first opening (20); a plurality of first supporting legs (8a,8b), extending from the first side of the back plate (8h); a first support plate (11), which is provided with a second opening (21) and is connected to free end regions of the first supporting legs (8a, 8b); a plurality of second supporting legs (8c, 8d, 8e, 8f), extending from the second side of the back plate (8h); and a second supporting plate (9), connected to the free end regions of the second supporting legs (8c, 8d, 8e, 8f). The first opening (20) and the second opening (21) receive the belt retracting cylinder (1). The safety belt retractor is simple in structure and easy to assembly. Also provided is a safety belt device comprising the safety belt retractor.

A seat belt assembly for a vehicle includes a pretensioner, and a cable connected to the pretensioner. The seat belt assembly includes a torsion bar having a plurality of teeth. The cable has slots interlocking with the teeth. During a sensed impact of the vehicle, the pretensioner is activated to retract the cable to pretension the seat belt assembly relative to an occupant of the vehicle. The interlocking of the slots with the teeth exerts torsional forces on the torsion bar, which yields to reduce forces on a chest of the occupant.

A restraint system includes a retractor housing; a spool rotatably coupled to the retractor housing and defining an axis of rotation; an inner torsion bar elongated along the axis of rotation and positioned coaxially in the spool; an outer torsion bar elongated along the axis of rotation, extending coaxially around the inner torsion bar, and positioned coaxially in the spool; an engagement member selectively engageable with the outer torsion bar; and a solenoid operable to move the engagement member into engagement with the outer torsion bar and out of engagement with the outer torsion bar.

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.

The invention relates to a belt retractor for a seat belt having a belt reel for winding up and unwinding the seat belt and a torsion bar which is arranged outside the belt reel and is connected at one bar end to a switchable fixing device. The switchable fixing device keeps the bar end rotationally fixed in one state and permits rotation of the bar end in another state. The switchable fixing device has a displaceable piston which, with a piston portion, in a locking position, can secure the bar end against rotation and, in a release position displaced in relation to the locking position, releases the bar end.