To provide an energy absorption apparatus, a seatbelt retractor, and a seatbelt apparatus that are capable of changing the energy absorption amount according to increases and decreases in the rotation speed between objects that rotate relative to each other and capable of improving endurance. The energy absorption apparatus includes a first plate connected to one of the objects and having a wave-shaped groove formed in an annular shape, a second plate connected to another one of the objects, disposed so as to be adjacent to the first plate, and having a plurality of radial grooves formed at locations that face the wave-shaped groove, a plurality of driving pins that are inserted, at one end, in the wave-shaped groove and inserted, at another end, in the radial grooves, and a plurality of follower bodies that are housed in the wave-shaped groove or the radial grooves and that slide along the wave-shaped groove as the driving pins move.

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.

In a webbing take-up device, a base cartridge receives pressure of gas generated by an MGG, load from a piston that is moved by the pressure of the gas, and reaction force acting on the MGG when gas has been ejected from the MGG. This enables strength retention with respect to the above-described pressure, load, and reaction force to be simplified.

[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.

A webbing take-up device includes a spool that is rotated in a pull-out direction by a webbing being pulled out and a lock base that limits pull-out direction rotation of the spool in a vehicle emergency. The webbing take-up device also includes a wire shaped energy absorbing wire that is deformed so as to permit pull-out direction rotation of the spool at or above a force limiter load after the lock base has limited pull-out direction rotation of the spool, a winder section to which one end of the energy absorbing wire is anchored and that is rotated so as to take up the energy absorbing wire, and a wire guide and a lever that press and deform the energy absorbing wire at position offset in the axial direction of the winder section with respect to a location where the energy absorbing wire is anchored to the winder section.

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 fluid damper for modulating a retaining force of a seat belt is provided. The fluid damper includes an outer cylinder and an inner cylinder. The inner cylinder encloses an inner space. The fluid damper includes a piston shiftable in the inner space. The fluid damper includes a duct. The duct conductively connects a front fluid chamber disposed in front of the piston to a rear fluid chamber disposed behind the piston and/or a reservoir for the damping fluid. The duct includes an outer duct portion and an inner duct portion. The inner cylinder is deflectable from a rest position by a force acting on the piston so that the deflection of the inner cylinder causes an adjustment of an overlap of the outer duct portion and the inner duct portion depending on the magnitude of the force.

A belt retractor for a vehicle seat belt comprises a rotatably supported belt reel from which webbing can be unwound, a force limiting means which in a force limiting phase permits controlled webbing extension in the webbing extension direction when the belt reel is blocked and a particular force threshold is exceeded, and a change-over device for performing a change-over operation during which it is changed between a low force limitation level and a high force limitation level. In accordance with the invention, the change-over device includes a control means which in response to the identification of an installed child safety seat suppresses a change-over operation from the low force limitation level to the high force limitation level and/or triggers a change-over operation from the high force limitation level to the low force limitation level.

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 force limiting device for a belt retractor is reversible from a higher restraining force level to a lower restraining force level by means of a reversing means during a force limiting phase, wherein the second restraining force level is largely determined by a performance of at least one force limiting element. The reversing means is arranged so that it accomplishes a significant work share upon reversing which is added to the performance of the force limiting element and thus temporarily increases the restraining force of the force limiting device. In this manner undershooting of the characteristic line of the force limiting device upon reversing to the lower restraining force level is compensated.