Restraint device for a vehicle

Patent metadata

Field	Value
Publication number	US-11084457-B2
Application number	US-201916712307-A
Country	US
Kind code	B2
Filing date	Dec 12, 2019
Priority date	Jun 12, 2017
Publication date	Aug 10, 2021
Grant date	Aug 10, 2021

Abstract

A restraint system for a vehicle, with which in a pre-crash phase prior to a predicted front crash time a vehicle occupant resting on a vehicle seat can be raised from a comfort position to an upright operative position by a forward displacer, in which in a crash phase a seat belt fastened on the vehicle occupant exerts a restraining effect on the vehicle occupant, in which an electromotive reversible belt pretensioner is activated to limit the restraining force exerted on the vehicle occupant to a predefined force level, namely by means of forward displacement of the vehicle occupant along a belt force limiting travel. In accordance with the invention, when raising the vehicle occupant to the operative position in the pre-crash phase, the electromotively reversible belt pretensioner generates a pre-crash belt slack so as to provide the pre-crash belt pullout travel required for raising the vehicle occupant in a restraining-force-free manner.

First claim

What is claimed is:

1. A restraint system for a vehicle, the restraint system comprising:
a forward displacer, with which in a pre-crash phase prior to a predicted front crash phase, a vehicle occupant resting on a vehicle seat is raised from a comfort position, in which a back rest of the vehicle seat is folded back, to an upright operative position, wherein, in the crash phase, a seat belt fastened on the vehicle occupant exerts a restraining effect on the vehicle occupant; and
an electromotively reversible belt pretensioner that is activated in order to limit the restraining force exerted on the vehicle occupant to a predefined force level during forward displacement of the vehicle occupant along a belt force limiting travel,
wherein, when raising the vehicle occupant to the upright operative position in the pre-crash phase, the electromotively reversible belt pretensioner generates a pre-crash belt slack in a shoulder belt portion of the seat belt to provide a pre-crash belt pullout travel necessary for raising the vehicle occupant in a restraining-force-free manner,
wherein the forward displacer is an inflatable cushion integrated in the back rest of the vehicle seat that is inflated in the pre-crash phase and acts as a pulse generator for raising the vehicle occupant to the upright operative position, and
wherein for supporting the forward displacer, the back rest of the vehicle seat is controlled to accelerate the raising of the vehicle occupant to the upright operative position by adjusting an incline of the back rest.

2. The restraint system according to claim 1 , wherein the seat belt is a three-point seat belt with a lap belt portion and the shoulder belt portion, wherein the lap belt portion in a fastened state extends between lateral attachment points transversely across a pelvis of the vehicle occupant, of which a first attachment point is a releasable buckle-belt tongue connection having a seat belt tongue and a buckle, wherein the shoulder belt portion extends in the fastened state diagonally across the upper body of the vehicle occupant up to an upper attachment point and onward to the electromotively reversible belt pretensioner, and wherein a second attachment point of the lap belt portion is a pyrotechnically activatable end fitting pretensioner which pulls a belt slack out of the lap belt portion in the event of a crash and thus reduces forward displacement of the pelvis.

3. The restraint system according to claim 2 , wherein the pyrotechnically activatable end fitting pretensioner is activated already in the pre-crash phase when raising the vehicle occupant to the upright operative position so as to ensure proper raising of the vehicle occupant to the upright operative position.

4. The restraint system according to claim 2 , wherein the seat belt tongue is a clamping tongue, which comprises a clamping element adjustable between a release position in which the seat belt is freely movable through the clamping tongue and a clamping position in which the seat belt is clamped in the event of a crash, so that in the pre-crash phase, the pre-crash belt slack generated in the shoulder belt portion does not transfer to the lap belt portion.

5. A restraint system for a vehicle, the restraint system comprising:
a forward displacer, with which in a pre-crash phase prior to a predicted front crash phase, a vehicle occupant resting on a vehicle seat is raised from a comfort position, in which a back rest of the vehicle seat is folded back, to an upright operative position, wherein, in the crash phase, a seat belt fastened on the vehicle occupant exerts a restraining effect on the vehicle occupant; and
an electromotively reversible belt pretensioner that is activated in order to limit the restraining force exerted on the vehicle occupant to a predefined force level during forward displacement of the vehicle occupant along a belt force limiting travel,
wherein, when raising the vehicle occupant to the upright operative position in the pre-crash phase, the electromotively reversible belt pretensioner generates a pre-crash belt slack in a shoulder belt portion of the seat belt to provide a pre-crash belt pullout travel necessary for raising the vehicle occupant in a restraining-force-free manner, and
wherein the restraint system further comprises a head impact airbag module having a head impact airbag that protects the head of the occupant, in the event of a crash, against an impact with an interior component, and wherein, if the restraint system detects a sufficiently large distance between the vehicle occupant and the interior component, the head impact air bag stays disabled thereby increasing a maximum belt force limiting travel available in the crash phase.

6. A method for restraining a vehicle occupant resting on a vehicle seat via a restraint system, the method comprising:
raising, in a pre-crash phase prior to a predicted front crash phase, a vehicle occupant resting on a vehicle seat from a comfort position, in which a back rest of the vehicle seat is folded back, to an upright operative position by a forward displacer, wherein in the crash phase, a seat belt fastened on the vehicle occupant exerts a restraining effect on the vehicle occupant;
activating an electromotively reversible belt pretensioner so as to limit the restraining force exerted on the vehicle occupant to a predefined force level during forward displacement of the vehicle occupant along a belt force limiting travel; and
generating a pre-crash belt slack in a shoulder belt portion of the seat belt when raising the vehicle occupant to the upright operative position in the pre-crash phase via the electromotively reversible belt pretensioner so as to provide a pre-crash belt pullout travel necessary for raising the vehicle occupant in a restraining-force-free manner,
wherein the forward displacer is an inflatable cushion integrated in the back rest of the vehicle seat that is inflated in the pre-crash phase and acts as a pulse generator for raising the vehicle occupant to the upright operative position, and
wherein for supporting the forward displacer, the back rest of the vehicle seat is controlled to accelerate the raising of the vehicle occupant to the upright operative position by adjusting an incline of the back rest.

Assignees

• Volkswagen Ag

Inventors

• Ryl Axel

Classifications

• B60R22/48

  Control systems, alarms, or interlock systems, for the correct application of the belt or harness · CPC title

• B60R2021/01265

  Seat belts · CPC title

• B60R22/26

  secured to the seat · CPC title

• B60R22/46 Primary

  {Reels} with means to tension the belt in an emergency {by forced winding up}(electrical circuits for triggering safety arrangements B60R21/01 {; tensioners using reels only guiding the belt during normal use, e.g. splitted reels B60R22/195}) · CPC title

• B60R21/207

  in vehicle seats · CPC title