Occupant safety system

An occupant restraint system comprising a seat belt webbing having a first end and a second end, the webbing configured to restrain the occupant; a member for anchoring the second end of the webbing; and an inflatable pretensioner having an inflator and an inflatable cushion that includes a first inflatable chamber and a second inflatable chamber, wherein the inflator is configured to inflate the first and second chambers of the cushion; wherein the first inflatable chamber is configured to deploy upon inflation to provide pretensioning of the webbing to restrain the secured occupant; wherein the second inflatable chamber is configured to deploy upon inflation to restrain the occupant.

BACKGROUND

The present application relates generally to the field of occupant restraint or safety systems. More specifically, this application relates to an active occupant restraint system configured to include an inflatable pretensioner to provide pretensioning to a webbing of the active occupant restraint system.

SUMMARY

According to a disclosed embodiment, an occupant restraint system is configured to provide restraint to an occupant of a vehicle. The occupant restraint system includes a seat belt webbing having a first end and a second end, the webbing configured to restrain the occupant; a member for anchoring the second end of the webbing; and an inflatable pretensioner having an inflator and an inflatable cushion that includes a first inflatable chamber and a second inflatable chamber. The inflator is configured to inflate the first and second chambers of the cushion, wherein the first inflatable chamber is configured to deploy upon inflation to provide pretensioning of the webbing to restrain the secured occupant and wherein the second inflatable chamber is configured to deploy upon inflation to restrain the occupant.

According to another disclosed embodiment, an inflatable pretensioner is configured to pretension a seat belt webbing of an occupant restraint system to thereby improve restraint of an occupant secured thereto. The inflatable pretensioner includes an inflatable cushion that includes at least one inflatable chamber and at least one non-inflatable portion, and an inflator for inflating the at least one chamber of the cushion. The at least one non-inflatable portion includes a first aperture and a second aperture, wherein the webbing passes through the first and second apertures to slideably couple the cushion to the webbing, such that the orientation of the webbing in a direction transverse to the length of the webbing is maintained relative to the at least one chamber, and wherein inflation of the at least one inflatable chamber provides pretensioning of the webbing to restrain the secured occupant.

DETAILED DESCRIPTION

Active occupant restraint systems provide restraint to secured occupants generally seated in seat systems of vehicles. As shown inFIG. 2, a conventional active occupant restraint system10may include a seat belt webbing11, a retractor mechanism12, a D-ring13, a buckle mechanism14, a tongue member15to selectively engage the buckle mechanism14, and an anchor assembly16having a conventional pretensioner16a. The seat belt webbing11may be made from a flexible woven nylon mesh to include a first end11ato couple to the retractor mechanism12and a second end11bto couple to the anchor and pretensioner assembly16. Between the first and second ends11a,11b, the webbing11may route through the D-ring13configured to couple to the vehicle (e.g., B-pillar) and the tongue member15, such that the webbing11is slideably coupled to the tongue member15and D-ring13. The portion of the webbing11between the D-ring13and the tongue member15forms a torso (e.g., shoulder) portion S, which routes over the torso of the occupant19to provide active restraint to the occupant19by restraining the chest or torso of the occupant during a vehicle dynamic event (e.g., a frontal impact). The portion of the webbing11between the tongue member15and the anchor and pretensioner assembly16forms a lap portion L, which routes over the lap of the occupant19to provide restraint to the occupant19by restraining the pelvis of the occupant during a vehicle dynamic event. Typically, during normal operation of the occupant restraint system10, there is some slack between the occupant19and the lap portion L and the shoulder portion S to allow for a higher degree of comfort for the restrained occupant19.

During a vehicle dynamic event, the conventional retractor mechanism12may limit or prohibit the webbing11of the active occupant restraint system10from extending or extracting (or “paying out”), and may further include a device, such as a pyrotechnic device, to wind or retract the webbing11to remove any such slack between the occupant19and the shoulder portion S of the webbing11. Further, during the vehicle dynamic event, the anchor assembly16having a conventional pretensioner16amay include an activating device, such as a pyrotechnic device, that when activated removes the slack between the occupant19and the lap portion L of the webbing11. The conventional pretensioner of the anchor assembly16may include a chamber having a piston, whereupon activation of the pyrotechnic, inflation gas is produced and fills the chamber creating pressure that drives the piston in a direction to impart a tension force into the lap portion L of the webbing11, since the second end11bof the webbing11is anchored to the piston. Thus, the motion of the piston removes the slack between the occupant19and the lap portion L of the webbing11. Reduced slack between the occupant restraint system10and the occupant19improves occupant safety by allowing for a reduced deflection of the occupant prior to actual restraint, which reduces the momentum of the occupant when restraint occurs, thus reducing the reaction forces into the occupant19.

With general reference toFIGS. 3-22, disclosed are occupant safety systems configured to provide improved occupant safety by providing pretensioning of the seat belt webbing during a vehicle dynamic event through an inflatable cushion positioned adjacent to the lap portion of the webbing. The occupant safety systems may further integrate an inflatable airbag cushion (e.g., pelvis airbag cushion) to protect the occupant or a portion of the occupant, whereby the occupant safety system provides pretensioning of the seat belt webbing of the active occupant restraint system and also provides passive restraint of the occupant through an inflatable cushion.

FIG. 1illustrates an exemplary embodiment of a vehicle9(e.g., a motor vehicle) that includes a passenger compartment having at least one seat system18configured to provide seating to an occupant19. The vehicle9may further include an active occupant restraint system20, which may be integrated into the seat system (which is to say the occupant restraint system may couple directly to the seat assembly), may operate independent of the seat system (which is to say the occupant restraint system may couple directly to vehicle components other than the seat system), or may be partially integrated and partially independent of the seat system (which is to say the occupant restraint system may couple directly to both the seat system and vehicle components other than the seat system). The occupant safety systems disclosed herein may be configured for use in any vehicle configured to include at least one occupant and the vehicles disclosed herein are not meant as limitations.

FIG. 3illustrates an exemplary embodiment of an active occupant restraint system20that is partially integrated and partially independent to a seat system having a seat back and seat cushion. The active occupant restraint system20may include a conventional retractor mechanism12coupled to the vehicle, a D-ring13coupled to the vehicle, a buckle mechanism14coupled to the seat cushion, a tongue member15to selectively engage the buckle mechanism14, a member40(e.g., an anchor member) coupled to the seat cushion, a seat belt webbing11, and an inflatable pretensioner21(shown stored or undeployed inFIG. 3).

A first end11aof the webbing11may be coupled to the retractor mechanism12and a second end11b′ of the webbing11may be coupled to the anchor member40. The webbing11may be routed to form a shoulder portion S and a lap portion L. The shoulder portion S may be routed over the shoulder of the occupant19to provide restraint to the occupant19, such as by restraining the chest of the occupant during a vehicle dynamic event (e.g., a frontal impact). The lap portion L may be routed over the lap of the occupant19to provide restraint to the occupant, such as by restraining the abdomen of the occupant during a vehicle dynamic event.

A section of the lap portion L of the webbing, such as the section adjacent to the second end11b′, which couples to the anchor member40, may route through the inflatable pretensioner21to maintain proper orientation between the seat belt webbing11and the inflatable pretensioner21, as well as proper orientation relative to the occupant19, such as proximate to the pelvic region of the occupant19. The inflatable pretensioner21may couple directly to the anchor member40thereby fixing the location of the coupled portion of the inflatable pretensioner21. Alternatively, the inflatable pretensioner21may couple directly to the seat system, such as the seat cushion, or to a vehicle component, such as the floor panel thereby fixing the location of the coupled portion of the inflatable pretensioner21.

FIGS. 4 and 5illustrate exemplary embodiments of active occupant restraint systems120,220shown partially integrated and partially independent to a seat system. The active occupant restraint systems120,220may be configured as disclosed above in reference to the occupant restraint system20shown inFIG. 3, except having the differences described below. As shown inFIG. 4, the inflatable pretensioner121may include an inflatable cushion123configured to provide pretensioning of the seat belt webbing11during a vehicle dynamic event. As shown inFIG. 5, the inflatable pretensioner221may include an at least one inflatable cushion223configured to provide pretensioning of the seat belt webbing as well as provide restraint to at least a portion of the occupant19, during a vehicle dynamic event. For example, the inflatable cushion223of the inflatable pretensioner221may include a first inflatable chamber225(e.g., inflatable portion) configured to inflate to provide the pretensioning of the seat belt webbing11and may include a second inflatable chamber227(e.g., inflatable portion) configured to inflate to provide restraint to the occupant19, such as the pelvic region of the occupant19.

FIGS. 6-10Aillustrate exemplary embodiments of integrated airbag (e.g., pelvis) and inflatable pretensioner assemblies221,321that include an inflatable airbag cushion223,323and an inflator222,322for inflating the cushion223,323. The airbag (e.g., pelvis) and pretensioner assembly221may also include a member, such as the member240shown inFIG. 8, to couple to the webbing and/or for anchoring the airbag assembly. The seat belt webbing11of the occupant restraint system20may route through the airbag cushion223,323, such as, for example, to couple to the member (e.g., the member240) to retain the coupled end of the webbing thereto.

The airbag cushion223,323may be made from one or a plurality of panels made from a flexible woven material (e.g., nylon mesh). The woven panels may be coupled together through conventional methods, such as stitching, to form at least one inflatable portion or chamber225,325. As shown inFIG. 6, the airbag cushion323may include a first inflatable chamber325and a second inflatable chamber327that is configured in direct fluid communication with the first chamber325to receive inflation gas therethrough. In other words, the inflatable chambers325,327may be positioned in series, where the inflator322may couple to the airbag cushion323to direct inflation gas (upon activation) into the first inflatable chamber325and the inflation gas enters the second inflatable chamber327upon exiting the first inflatable chamber325.

As shown inFIG. 7, the airbag cushion223may include a first inflatable chamber225and a second inflatable chamber227, wherein the second chamber227is configured having indirect fluid communication with the first chamber225. In other words, the two chambers225,227may be configured in parallel, where the inflator may couple to the airbag cushion223to direct inflation gas into the first chamber225and/or second chamber227without having to previously pass through the other inflatable chamber. This allows for both inflatable chambers225,227to be inflated substantially simultaneously. The airbag223,323configuration may tailor the sequence or function of the integrated airbag (e.g., pelvis) and inflatable pretensioner assemblies221,321of the occupant restraint system20. For example, the configuration ofFIG. 6drives inflation of the first inflatable chamber225prior to inflation of the second inflatable chamber227, thus, providing pretensioning, such as through inflation of the first chamber225, earlier in the deployment sequence relative to the protection of the occupant, such as through inflation of the second chamber227to restrain and protect the pelvic region of the occupant.

The airbag cushion223,323of the integrated airbag (e.g., pelvis) and inflatable pretensioner assemblies221,321may further include one or a plurality of non-inflatable portions229,329. The non-inflatable portions229,329may be configured to divide the airbag cushion223,323into one or more inflatable chambers. For example, the non-inflatable portion229may divide the airbag cushion223into first and second chambers225,227that are in indirect fluid communication. As another example, the non-inflatable portion329may divide the airbag cushion323into first and second chambers325,327, where the second chamber327is in direct fluid communication with the first chamber325.

The airbag cushion may include one or more apertures or slits that may be located on a non-inflatable portion, an inflatable portion, or a combination thereof. The apertures or slits may be configured to receive the webbing of the occupant restraint system to slideably couple the webbing and the inflatable pretensioner. As shown inFIGS. 17 and 19, the airbag cushion623may include one aperture631that may be provided between a first inflatable chamber625and a second inflatable chamber627, wherein the webbing11may pass through the aperture631(as well as through the openings of the member640) to slideably couple the webbing and the inflatable pretensioner621. As shown inFIGS. 6 and 7, the airbag cushions223,323(e.g., the non-inflatable portions229,329) may include a plurality of apertures231,331(e.g., slits), wherein each aperture231,331may allow for the seat-belt webbing to pass therethrough to couple (e.g., slideably couple) the cushion and webbing. The size, shape, and location of the apertures231,331,631may vary and preferably are tailored to the width and thickness of the seat belt webbing to maintain a proper orientation of the inflatable pretensioner. As shown inFIGS. 6 and 7, the airbag cushion223,323may include two apertures231,331provided in non-inflatable portions229,329, where the two apertures231,331are located on opposing sides of the first inflatable portion225,325. This configuration slideably couples the airbag cushion223,323to the webbing11. Thus, the section of the webbing11that passes through one or both apertures231,331may change, such as during pretensioning of the webbing11by the assemblies221,321, while maintaining an orientation of the webbing in a direction that is transverse to the length of the webbing11relative to the cushion223,323. This helps maintain the proper location of the cushion223,323relative to the webbing11and/or secured occupant.

As shown inFIG. 22B, the airbag cushion623may include an inner panel and an outer panel that are coupled together, such as through stitching, to define the first inflatable chamber625and the second inflatable chamber627. This configuration forms one layer of cushion623that the aperture631may be provided therethrough. Accordingly, the webbing11may pass through the one aperture631in the single layer of the cushion623to slideably couple the cushion to the webbing. Alternatively, as shown inFIG. 22C, the airbag cushion623may include a plurality of panels, such as an inner panel, an outer panel, and one or more intermediate panels. The intermediate panels may be provided between and coupled to the inner and outer panels to form an airbag cushion623that defines the first and second inflatable chambers625′,627′ and forms more than one layer of the cushion623in the region where the apertures631′ are located. The cushion623, shown inFIG. 22C, having two layers of cushion between the inflatable chambers625′,627′ includes an aperture631′ in each layer. Accordingly, the webbing11may pass through both apertures631′ in the cushion to slideably couple the cushion to the webbing. This configuration may provide additional support to better maintain the relative orientation between the inflatable pretensioner and the webbing11and/or may provide additional pretensioning of the webbing, such as during deployment of the first inflatable chamber625′.

The airbag cushion or any inflatable chamber, such as the first inflatable chamber225, of the cushion223may be packaged for storage through a series of rolls and/or folds, such as shown inFIG. 8A. The airbag cushion323may include one or a plurality of fastening devices, such as tack-stitches, to maintain the stored (e.g., folded and/or rolled) configuration of the inflatable chamber225of the airbag cushion223, during assembly and prior to deployment. The fastening device may be configured to break loose or tear when subjected to a relatively low tension force. Thus, the fastening device may maintain the stored configuration of the airbag cushion223, but may tear during deployment when subjected to a relative low tension force, so as not to impede or alter deployment of the airbag cushion223.

Further, as shown inFIGS. 8 and 8A, the seat belt webbing11may route from the side of the airbag cushion223that is opposite the side having the stored first inflatable chamber225through a first opening241(e.g., aperture) in the member240and a first aperture231in the cushion223to the side of the airbag cushion223having the stored first inflatable chamber225, where the webbing11may pass over the stored first inflatable chamber225, then the webbing may pass through a second aperture231in the cushion223and a second opening242(e.g., aperture) in the member240, then may route adjacent to the member240on the side of the cushion223that is opposite to the stored first inflatable chamber225. The end11b′ of the webbing11may be fixed. For example, the end11b′ of the webbing11may form a loop around the member240by passing through third and fourth openings243,244(e.g., apertures) in the member240, whereby the end11b′ of the webbing11may be coupled (e.g., by stitching) to a portion of the webbing11, which fixes the webbing11to the member240. The webbing11may also be coupled directly to the member240without the webbing11forming a loop, such as, for example, by having a fastener (e.g., rivet, screw, bolt, etc.) couple the webbing11to the member240. The airbag cushion223may be coupled directly to the member240and/or the webbing11(which may pass through apertures/openings in both the cushion and the member) to help maintain proximity and orientation of the cushion223relative to the member240, the webbing11, and/or the secured occupant.

The member (e.g., the member240) may be made from steel or any suitable material strong enough to withstand the forces generated during a dynamic vehicle event where the occupant imparts loading forces into the seat belt webbing by restraining the occupant. As shown inFIGS. 9 and 9A, the member240may be substantially flat or may be formed to improve the structural rigidity of the member240. The member240may include a plurality of slot-shaped openings or apertures (e.g., openings241,242,243,244) configured to allow the seat belt webbing11to pass therethrough. The member240may further include a round aperture or hole245to allow the anchoring fastener250to pass through to thereby couple and retain the member240to a vehicle component, such as the seat cushion frame or the floor panel. The anchoring fastener250may be any suitable fastener (e.g., bolt, screw, or rivet). Furthermore, the member240may include a flange and/or apertures to allow for coupling of the inflator222to the member240. Alternatively, the inflator222may couple directly to any other vehicle component, such as the seat cushion frame or the floor panel.

As shown inFIGS. 14-15, the member540may include a base540a(e.g., a flat portion) having a plurality of openings, which may be configured to receive the webbing11, a fastener to couple the member540to another device or component, or any suitable element (e.g., the inflator, the cushion, etc.). The member540may also include a pair of opposing flanges563that extend substantially perpendicular from the base540a, where the flanges563may be configured to receive a portion of a locking mechanism560. For example, each flange563may include an opening (e.g., a slot)564that receives a portion of the locking mechanism560.

As shown inFIGS. 20-22A, the member640may include a base640aportion and a U-shaped portion670that extends from the base640a. The U-shaped portion670of the member640may define a cavity671that has an opening672at the top of the cavity671. The cavity671formed by the member640may be configured to house all or a portion of the stored airbag cushion623, such as a first inflatable chamber of the cushion. The cavity671may also house the inflator622and have a feature (e.g., hole) to provide for attachment of the inflator622to the member640. The airbag cushion623(or portion thereof) may deploy through the opening672, such as, for example, to pretension the webbing11passing adjacent to the opening672. It should be noted that the member may have any suitable shape and size and the embodiments disclosed herein are not meant as limitations.

FIGS. 11-13Aillustrate another embodiment of an integrated airbag (e.g., pelvis) and inflatable pretensioner assembly421that includes an airbag cushion423, an inflator422for inflating the cushion, a guide member445for routing the webbing and for providing structural support, and an anchor member440to couple to the webbing11and/or for anchoring the inflatable pretensioner assembly421. The airbag cushion423may be configured as disclosed herein to include a first inflatable chamber425to provide pretensioning to the seat belt webbing11. The airbag cushion may further include a second inflatable chamber427to provide protection or direct restraint to an occupant or a portion of the occupant, such as to the pelvic region of the occupant.

The guide member445may be substantially flat and may include a first slot-shaped opening447(e.g., aperture) and second slot-shaped opening448(e.g., aperture) configured to allow the seat belt webbing11to pass therethrough. The size and shape of the guide member445and openings447,448therein may be varied in size and shape. The guide member445may include forms, flanges, or other features to improve strength or to improve function, such as to couple other components thereto. The first and second openings447,448may relatively align with the first and second apertures431,432, respectively, in the airbag cushion423, such as after manipulating the first inflatable chamber425of the cushion423into the stored configuration, to allow the webbing11to pass through and maintain a relative orientation between the cushion423and the guide member445. The webbing11may route from the side of the airbag cushion423that is opposite the side having the stored (e.g., folded and/or rolled) first inflatable chamber425through the first opening447in the guide member445and the first aperture431in the cushion423to the side of the airbag cushion423having the first inflatable chamber425, where the webbing11passes over and adjacent to the stored first inflatable chamber425, then the webbing11passes through the second aperture432in the cushion423and the second opening448in the guide member445, then may route adjacent to the guide member445on the side of the cushion that is opposite to the first inflatable chamber425. As shown inFIG. 11, the second aperture432may be located in a non-inflatable region429of the airbag adjacent the perimeter of the airbag.

As shown inFIGS. 12 and 12A, the anchor member440may be substantially flat and may include a first slot-shaped opening441(e.g., aperture) that is configured to allow the end of the seat belt webbing11to pass therethrough, and a second round opening442(e.g., aperture) to allow an anchoring fastener450to pass therethrough. The anchor member440may include forms, flanges, or other features to improve strength or to improve function, such as to couple other components (e.g., an inflator) thereto. The round opening442may receive a fastener450to couple and retain the anchor member440to a vehicle component, such as the seat cushion frame or the floor panel. The anchoring fastener450may be any suitable fastener (e.g., bolt, screw, or rivet). The end11b′ of the webbing11may be fixed to the anchor member440. For example, the webbing11may form a loop by passing through the slot shaped opening441in the anchor member440, whereby the end11b′ of the webbing11may be coupled (e.g., by stitching) to a portion of the webbing11. The webbing11may also be coupled directly to the anchor member440without the webbing11forming a loop, such as by having a fastener couple the webbing11to the member440.

During a dynamic vehicle event triggering pretensioning of the seat belt webbing11, the inflator (e.g., the inflator222) is activated, which begins producing inflation gas to expand the airbag cushion (e.g., the airbag cushion223). According to an exemplary embodiment, the inflation gas fills the first inflatable chamber (e.g., the first inflatable chamber225), increasing the internal pressure of the first inflatable chamber, which expands and unfolds the stored first inflatable chamber. Because the webbing routes over the top of the first inflatable chamber (e.g., the first inflatable chamber225) of the airbag cushion (e.g., the airbag cushion223), the expansion (i.e., the increase in cross-sectional profile, such as the circumference shown inFIGS. 10A,13A, and22) of the first inflatable chamber forces the length of webbing circumscribing the expanding first inflatable chamber of the airbag cushion to increase correspondingly. The fixed end11b′ of the webbing11is unable to give up any substantial length (only a minor length of webbing due to clearances and slack can be removed) of webbing11to circumscribe the expanding first inflatable chamber (e.g., the first inflatable chamber225), therefore, the webbing pretensioning portion (i.e., the portion that extends away from the first inflatable chamber and forms the lap portion L of the webbing11) is forced to displace toward the first inflatable chamber (e.g., the first inflatable chamber225) to provide the length of webbing necessary to circumscribe the expanding airbag cushion. This displacement of the lap portion L of the webbing11toward the first inflatable chamber (e.g., the first inflatable chamber225) acts to retract the webbing toward the fixed end11b′ of the webbing11, which removes the clearances and slack in the webbing, such as the slack between the webbing and the restrained occupant. Thus, by having an internal pressure greater than the tension force in the webbing, the expanding first inflatable chamber (e.g., the first inflatable chamber225) pretensions the webbing11by forcing the webbing11to circumscribe the increasing profile (e.g., circumference) of the expanding first inflatable chamber (e.g., the first inflatable chamber225), which displaces the webbing11in a direction that removes the clearance between the webbing and the occupant.

The length of the webbing11extracted (i.e., moved, taken up) during the pretensioning may be controlled by the dimensions (e.g., circumference) of the outer profile of the first inflatable chamber (e.g., the first inflatable chamber225) of the airbag cushion (e.g., the airbag cushion223). Thus, the length of the webbing11extracted during the pretensioning may be tailored by varying the dimensions of the outer profile of the first inflatable chamber (e.g., the first inflatable chamber225). The dimensions of the outer profile may be varied by changing the profile of the inflated chamber (e.g., the first inflatable chamber225) when fully inflated, or may be varied by changing the amount of inflation gas used to inflate the first inflatable chamber (i.e., less inflation gas would inflate the inflatable chamber to a smaller circumference or profile length).

The airbag cushion of the inflatable pretensioner may be configured such that inflation gas may fill both the first inflatable chamber and the second inflatable chamber, where the gas may fill both chambers substantially simultaneously, in series, or in any suitable progression. The airbag cushion may also be configured to include any number of chambers, which may have any suitable progression of inflation or deployment.

The occupant restraint (or protection) system20and/or the inflatable pretensioner, such as the inflatable pretensioner521shown inFIGS. 14-15, may further include a locking member or locking mechanism560to prohibit the webbing11from extracting (i.e., moving in a direction to increase slack or clearance between the webbing and the occupant, which would be opposite to the pretensioning direction) during a vehicle dynamic event. According to an exemplary embodiment, the locking mechanism560may allow the webbing to be extracted or retracted during normal vehicle use (i.e., not a dynamic-impact or rollover event), such as for the occupant19to adjust the webbing11for comfort. However, during a vehicle dynamic impact event, the webbing11may only be allowed to be retracted for pretensioning and is prohibited from being extracted. Thus, during a dynamic impact event, the slack (i.e., clearance between occupant and webbing) may be removed, such as by the pretensioning by the first inflatable chamber525of the airbag cushion523, yet the slack removed during such pretensioning may not be given up (or extracted), since the locking mechanism560prohibits the webbing11from being extracted. The locking mechanism560may be configured to allow for the webbing to be extracted during normal vehicle usage (i.e., not during a sudden dynamic change to the vehicle), to allow for comfort adjustment for the restrained occupant.

As shown inFIGS. 14-16, the locking mechanism560may be integrated with the member540of the inflatable pretensioner521, where the member540may be configured to anchor the inflatable pretensioner521, as disclosed herein. The locking mechanism560may include a sliding bar561and a biasing member562(e.g., spring). The locking mechanism560may also include two opposing flanges563with each flange563having a slot564configured to receive a portion of the sliding bar561. The slot564may be configured to allow the sliding bar561to displace along the length of the slot564in the non-locking (or open) direction, which is shown by the arrow labeled D1inFIG. 15, and in the locking (or closed) direction D2, which is opposite the direction D1, as shown inFIG. 16. The locking mechanism560is configured to have two positions, a first locking (or closed) position and a second non-locking (or open) position. When the locking mechanism560is configured in the first locking position, the webbing11of the occupant restraint system20is prohibited from sliding in a direction D4, as shown inFIG. 16, yet may slide in a direction D3. Thus, the webbing11may be pretensioned (e.g., moved in the direction D3) by the expanding cushion523(e.g., first inflatable chamber525) to remove slack between the webbing11and the secured occupant being restrained by the webbing11, but the webbing11is prohibited from sliding in the direction D4that would release the pretensioning and add slack between the webbing11and the secured occupant. When the locking mechanism560is configured in the second non-locking position, the webbing11of the occupant restraint system20is allowed to freely slide in either the direction D3or D4.

As shown inFIGS. 14 and 14A, the sliding bar561may include a body565that may be provided between the two opposing flanges563of the member540and an extension566extending from each end of the body565. The extension566is configured for engaging the slot564in the flange563of the member540, such that the extension566may displace along the length of the slot564as the body565moves in the direction D1or the direction D2. Thus, the sliding bar561may displace along the length of the slot564as the two extensions566slide within the two slots564. The sliding bar561may further include an engaging portion567that is configured to engage the webbing11to lock the webbing11in place. For example, the engaging portion567may include a plurality of teeth configured to engage the webbing11, such that the portion of the webbing11engaged is prohibited from sliding (e.g., extracting, retracting) relative to the sliding bar561. In other words, the engaging portion567may pinch the webbing11between the sliding bar561and the member540to prohibit movement of the webbing11relative to the locking mechanism560.

As shown inFIGS. 20-22, the locking mechanism660may include a rotating bar661that is configured to selectively rotate about a pivot axis in order to lock (e.g., clamp) a section of the webbing11. The rotating bar661may be configured with a body665and with ends666that are smaller in diameter relative to the body665, where the ends666engage holes in the member640, such as holes in the flanges of the member640, that define the pivot axis of the rotating bar661. The rotating bar661may further include an engaging portion667that is configured to engage a section of the webbing11to retain the section and prevent movement of the webbing11relative to the locking mechanism660.

The biasing member (e.g., biasing member562) may be a spring (e.g., a coil spring, extension spring) that imparts a biasing force onto the sliding bar561of the locking mechanism560, such that the biasing member562biases the sliding bar561into the locking position (i.e., into contact with the webbing11). The biasing member562may be configured to be any suitable spring or device that provides a biasing force. The biasing member562may also be configured to bias the sliding bar561in any suitable direction (e.g., in a non-locking direction, in a locking direction).

During deployment of the inflatable pretensioner (e.g., inflatable pretensioner521), such as inflatable pretensioner521, the first chamber525of the airbag cushion523expands in a direction away from the member540, as shown inFIG. 15, and accordingly pulls the section of webbing11that is adjacent to the expanding first chamber525with the cushion, imparting a tension into the webbing11. In effect, as the inflating cushion523(e.g., the first chamber525) expands, the outer profile or periphery (e.g., diameter) of the cushion523increases in length (e.g., circumference), thereby forcing the length of the webbing11that is adjacent to the cushion523(e.g., first inflatable chamber525) to increase in length a similarly corresponding amount. However, because the webbing11has the end11b′ fixed (e.g., coupled to the member540), the additional length of the webbing11required to at least partially circumscribe the expanding periphery of the cushion523is primarily taken from the lap portion L and/or the shoulder portion S of the webbing11, thereby removing the clearance (or slack) between the webbing11and the secured occupant that was present prior to deployment. In other words, the expanding cushion523operates to retract or move the webbing11in the pretensioning direction D3relative to the locking mechanism560to pull the webbing11tight to reduce the slack between the webbing11and occupant to improve restraint of the secured occupant.

The forces from the expanding cushion523and the retracting of the webbing11overcome the biasing force from the biasing member562, which causes the sliding bar561to move (e.g., displace, slide) in the direction D1to the open (or non-locking or unlocked) position, which permits the webbing11to continue to retract (i.e., move in the pretensioning direction D3) during inflation and expansion of the airbag cushion523. The retracting of the webbing11provides pretensioning to the seated occupant by removing the slack or clearance between the restrained occupant and the webbing11of the active restraint system.

After the occupant contacts the webbing11, the loads induced by the accelerating occupant are transferred into the webbing11as forces opposing the pretensioning forces on the webbing, which act in the direction to extract (or unwind) the webbing11. The opposing forces may overcome the pretensioning forces that act to position the sliding bar561of the locking mechanism560in the open position, such that the biasing member562and/or the loading on the webbing from the occupant cause the sliding bar561to move (e.g., displace, slide) in the direction D2to the locking position, thereby prohibiting extraction (e.g., movement in the direction D4) of the webbing11relative to the locking mechanism560.

The locking mechanism560(e.g., locking member) may be driven into the locking position (e.g., during a vehicle impact event) to prevent extraction of the seat belt webbing11through a force from the biasing member562(e.g., spring), by inertia of the vehicle (e.g., sudden deceleration of the vehicle), or by any suitable method. When configured in the locking position, the locking mechanism560may allow for further retraction or pretensioning (i.e., movement of in the pretensioning direction D3) of the webbing11, such as by a pretensioning device, yet may prohibit extraction or unwinding (i.e., movement in the direction D4) of the webbing11, so that slack or clearance removed by the pretensioning device between the occupant and the seat belt webbing11may not be reclaimed by forces imparted by the occupant onto the webbing11. It should be noted that other suitable locking mechanisms may provide for selective clamping (or locking) of the webbing11during operation and that the locking mechanisms illustrated herein are not meant as limitations.

The inflatable pretensioners of the occupant restraint (or protection) systems, as disclosed herein, that have more than one inflatable chambers may utilize a single inflator (e.g., the inflator222, the inflator322, etc.) to inflate the more than one inflatable chamber, or may include more than one inflator to inflate the different chambers. As shown inFIG. 7, for example, the inflatable pretensioner221may include a single inflator222that is configured to inflate both the first inflatable chamber225to pretension the seat belt webbing11and the second inflatable chamber227to further restrain or protect the secured occupant or a portion (e.g., the pelvis) of the occupant. Thus, during a dynamic vehicle event triggering activation of the inflator, the inflation gas generated may expand and inflate one or more inflatable chambers of the airbag cushion. As shown inFIG. 6, the airbag cushion323may be configured so that inflation gas must pass through the first inflatable chamber325to enter the second inflatable chamber327. Alternatively, as shown inFIGS. 7,8,10,11and13, the airbag cushions of the inflatable pretensioners may be configured so that inflation gas may pass into more than one chamber substantially simultaneously. It should be noted that the inflatable pretensioners, as disclosed herein, may include any number of inflatable chambers, which may be inflated by the same or a separate inflator and may be inflated in series or in parallel to the other inflatable chambers of the airbag cushion.

As shown inFIG. 17, the inflatable pretensioner621may include an inflator622that is positioned transverse to the direction of the webbing11, or, as shown inFIG. 6, may include an inflator322that is positioned parallel to the direction of the webbing11. It should be noted that the inflator may be positioned at any suitable orientation or may be located anywhere on the inflatable pretensioner, and the embodiments disclosed herein are not meant as limitations.

It should also be noted that the active occupant restraint systems, as disclosed herein, may be configured to include both an integrated airbag cushion (e.g., pelvis cushion) and an inflatable pretensioner, as shown inFIG. 5, or may be configured to include solely an inflatable pretensioner, such as shown inFIG. 4. The latter embodiment shown inFIG. 4may include an airbag cushion having an inflatable portion configured similar to the first inflatable portions ofFIGS. 6 and 7, but without any additional inflatable chambers (or portions). The inflator of this embodiment may be smaller in size and may be configured to produce less inflation gas relative to the inflator used in the embodiment ofFIGS. 6 and 7, which may allow for a reduced mass and cost. The airbag cushion of the occupant safety system having only an inflatable pretensioner may further include apertures or slits to allow the webbing to pass through and may include a member to anchor and provide structural rigidity to the airbag assembly.