A rollover curtain for a vehicle

Abstract: A vehicle occupant restraint system includes a restraint curtain 36 stowed adjacent a roof rail 32 of the vehicle 10 to deploy downwardly adjacent the side wall 12 of the vehicle. The curtain 36 is formed with a slit 42 dividing the curtain into first and second sections 36a and 36b that are tied together by a short, rod-like connecting member 44 which spans the slit 42. A ring 54 encircles the connecting member 44 and a flexible tether 52 is attached to the ring 54. The end of the tether 52 opposite the ring 54 is slidingly engaged with a guide track 46 disposed on a pillar 22 extending downwardly from the vehicle roof 30. The connecting member 44 is therefore free to rotate within the ring 54 so that the curtain 36 may roll and unroll freely without the tether 52 becoming wound up in or otherwise entangled with the curtain 36. When the curtain 36 is in the stowed condition, the tether 52 is slid to the upper end of the guide track 46. As the curtain 36 unrolls to the deployed condition the tether 52 travels downwardly along the guide track 46 holding the lower edge of the curtain 36 close to the pillar 22.

Description: This invention relates generally to occupant restraints for automotive vehicles, and more particularly to curtain-type restraints deployed adjacent the side windows of the vehicles to protect occupants during rollover and/or side impact events. It is known to use deployable side curtains in automotive vehicles to protect vehicle occupants during side impact and/or rollover events. Such side curtains, also commonly known as rollover curtains, may take the form of a flexible curtain (usually made of a mesh material) covering the side windows to protect against the occupants being ejected through the doors or windows, or an inflatable airbag which protects against ejection and also provides a degree of cushioning. Prior to deployment, a side curtain is typically folded or rolled into a compact, elongated shape that is secured to the vehicle adjacent the roof rail above a window opening or door opening. Interior trim panels cover the stowed curtain to hide it from view. In the deployed condition, the side curtain extends downwardly from the roof rail to at least partially cover the window/door openings and/or the pillars adjacent the openings. One or more curtains may be disposed along the length of the passenger compartment as necessary to provide protection to occupants in any or all of the rows of seats in the passenger compartment. U.S. Patent No. 6,000,715 teaches a non-inflatable side curtain. U.S. Patent No. 5,540,459 teaches an inflatable side curtain. U.S. Patent No. 5,788,270 teaches a side curtain comprising both inflatable and non-inflatable sections. During a vehicle rollover or other type of side impact event, the side curtain should move from its stowed condition to its deployed condition rapidly and the lower edge of the curtain should be held close to the side of the vehicle during deployment in order to ensure that the curtain passes between the occupant and the side wall of the vehicle before any part of the occupant's body moves outboard of the curtain. It is known to attempt to keep the curtain close to the vehicle side wall by means of tethers, cords, or similar members connecting the forward and/or the rear lower corners of the curtain to the vehicle structure when in the deployed condition. For some curtain configurations, however, it may be desirable to connect the curtain to the vehicle structure at some point on the lower edge of curtain lying between the forward and rear corners. For example, when a restraint curtain extends along two or more rows of occupant seating, connecting the midpoint of the curtain to the adjacent B-pillar or other structure may improve the deployment dynamics and post-deployment stability of the curtain. U.S. Patent No. 5,788,270 teaches a curtain having a tab at the midpoint of its lower edge, the tab engaging a channel extending generally vertically along the B-pillar of the vehicle. The tab is urged downward along the channel as the curtain deploys, with the engagement between the tab and the channel holding the lower edge of the curtain closely adjacent the B-pillar throughout its deployment. This configuration requires that the curtain be folded such that, when in the stowed condition, its lower edge is exposed on the outside of the folded curtain and immediately adjacent to the channel so that the tab may be connected with the channel. To ensure proper deployment, however, a curtain is often folded or rolled inwardly on itself so that the lower edge is buried in the interior of the stowed curtain. For example, in some circumstances optimum curtain deployment is achieved by placing the curtain in the stowed condition using a "roll fold" in which the curtain, starting at the lower edge, is rolled upwardly in a spiral fashion toward the upper edge. When a curtain is folded in this manner, the lower edge of the curtain cannot be connected directly to the vehicle structure as taught by US Patent 5,788,270. While it is possible to attach a tether to the curtain at a midpoint of the lower edge and simply roll the tether up into the curtain, this requires the tether to be longer than the vertical dimension of the curtain. A tether this long would have to be tightened by some mechanical actuator during deployment of the curtain, with resulting increases in the complexity, cost, and deployment time of the restraint system. It is an object of the present invention to provide a vehicle occupant restraint system in which a restraint curtain is stowed in a manner to provide superior stability and positioning of the curtain during and after deployment. A system and a method according to the preambles of claims 1 and 9 are for instance known from document EP-A-0 814 001. According to a first aspect of the invention there is provided an occupant restraint system for an automotive vehicle having a roof and a pillar extending downwardly from the roof to define a lateral edge of an opening, the system comprising an occupant restraint curtain having a first edge securable to the roof adjacent an upper edge of the opening and an opposite second edge, the curtain is movable between a stowed condition wherein the curtain is retained adjacent the roof and a deployed condition wherein the curtain is generally planar and extends downwardly from the roof to cover at least a portion of the opening, the curtain comprising first and second sections separated by a slit extending from the second edge toward the first edge, a connecting member attached to the curtain adjacent the second edge thereof to span the slit and connect the first and second sections, characterised in that the system further comprises a tether having a first end engageable with the pillar for movement therealong when the curtain moves between the stowed and deployed conditions, the tether having a second end rotatably engaged with the connecting member whereby the connecting member is free to rotate relative to the tether as the curtain moves between the stowed condition and the deployed condition. The first edge of the curtain may be securable to a roof rail extending generally parallel to the upper edge of the opening. The stowed condition may be achieved by rolling the second edge of the curtain towards the first edge of the curtain. The curtain may be an airbag that is inflated to deploy the airbag. The connecting member may be rigid. The system may further comprise a ring connected to the second end of the tether and encircling the connecting member. The system may further comprise a guide track extending along the pillar for engagement with the second end of the tether. The curtain may have a second slit extending generally parallel to the first slit, and further comprises a second connecting member attached to the curtain adjacent the second edge thereof to span the second slit; and a second tether having a first end engageable with the pillar for movement therealong when the curtain moves between the stowed and deployed conditions, the second tether having a second end rotatably engaged with the second connecting member whereby the second connecting member is free to rotate relative to the second tether as the curtain moves between the stowed condition and the deployed condition. According to a second aspect of the invention there is provided a method of securing an occupant restraint curtain in an automotive vehicle having a roof defining an upper edge of an opening and a pillar extending downwardly from the roof to define a lateral edge of the opening, the method comprising the steps of providing an occupant restraint curtain comprising first and second sections separated by a slit extending from a first edge of the curtain toward an opposite second edge of the curtain, and a connecting member attached to the curtain adjacent the first edge thereof to span the slit and connect the first and second sections, characterised in that the method further comprises the steps of rolling the first edge of the curtain toward the second edge such that the connecting member remains accessible through the slit, securing the second edge of the curtain to the vehicle adjacent the top edge of the opening, attaching a first end of a tether to the pillar for movement therealong, and rotatably engaging a second end of the tether with the connecting member whereby the connecting member is free to rotate with respect to the tether as the curtain moves between the stowed and the deployed positions. The step of attaching a first end of the tether to the pillar may comprise engaging the first end of the tether with a guide track extending along the pillar. Further, there may be provided a method of placing an occupant restraint curtain for an automotive vehicle in a stowed condition, the method comprising the steps of securing a first end of a tether to a first edge of the curtain, folding the curtain generally in half to place the first edge adjacent an opposite second edge and form a crease edge opposite the tether, rolling the curtain in spiral fashion, starting at the crease edge and rolling toward the first and second edges, whereby the tether is exposed on an outside of the roll when in the stowed condition. Moreover, there may be provided an occupant restraint curtain for use in an automotive vehicle having a roof defining an upper edge of an opening and a pillar extending downwardly from the roof to define a lateral edge of the opening, the curtain comprising a first edge securable to the roof adjacent the upper edge of the opening a second edge opposite the first edge, the curtain movable between a stowed condition wherein the curtain is compacted for storage adjacent the roof and a deployed condition wherein the curtain is generally planar to extend downwardly from the roof and cover at least a portion of the opening first and second sections separated by a slit extending from the first edge toward the second edge, a connecting member attached to the curtain adjacent the second edge thereof to span the slit and connect the first and second sections and a tether having a first end engageable with the pillar and a second end rotatably engaged with the connecting member whereby the connecting member is free to rotate with respect to the tether. In which case, the stowed condition of the curtain may be achieved by rolling the second edge toward the first edge. The opening may be a door opening. The curtain may have a second slit extending generally parallel to the first slit, and further comprising a second connecting member attached to the curtain adjacent the second edge thereof to span the second slit and a second tether having a first end engageable with the pillar and a second end rotatably engaged with the second connecting member whereby the second connecting member is free to rotate relative to the second. A motor vehicle including a restraint system according to said first aspect of the invention can also be provided. The invention will now be described by way of example with reference to the accompanying drawing of which: Figure 1 is an interior view of an automotive vehicle showing the restraint curtain of the present invention in a deployed condition; Figure 2 is a detailed view of the automotive vehicle interior with trim panels removed to show the restraint curtain in a stowed condition; Figure 3 is a detail view of the lower edge of the curtain in the deployed condition; Figure 4 is a cross-sectional view taken along lines 4-4 of Figure 1 with the curtain in the stowed condition; Figure 5 is a cross-sectional view similar to that of Figure 4 showing the restraint curtain in the deployed condition; Figure 6 is a cross-sectional view taken along lines 6-6 of Figure 1 with the curtain in the deployed condition; Figure 7 is a cross-sectional view similar to that of Figure 6 showing another embodiment of the invention in which two guide tracks restrain the curtain; Figures 8 and 9 are perspective views showing steps in a second method of folding a curtain; and Figure 10 is a cross-sectional view showing the curtain of Figures 8 and 9 in the stowed condition. As seen in Figure 1, an automotive vehicle 10 is illustrated as including a body having a side wall 12. A front door 14 and a rear door 16, each having respective windows, act as closure panels with respect to the side wall 12. An A-pillar 18 bounds the forward end of the front door 14 and a B-pillar 20 bounds the rearward end. The rearward end of the rear door 16 is bounded by a C-pillar 22. The passenger compartment of the vehicle is indicated generally and has a steering wheel 24 and front and rear seats 26,28. The passenger compartment is vertically bounded on its top by a roof 30, and a roof rail 32 is fixed securely to the roof and extends generally horizontally above the doors 14,16, as is well known in vehicle body construction. A rear side window 34 is located rearward of the C-pillar 22, such as may be the case in a light truck or a sport utility vehicle. It will be appreciated that the above-described vehicle configuration does not constitute a limitation on the scope of the invention, as the invention may be utilized in a vehicle with any number of doors, windows, or rows of seating. The roof rail 32 carries an inflatable restraint curtain 36. Figure 1 shows the restraint curtain 36 in a fully inflated or deployed condition wherein it extends downwardly from the roof rail 32 to substantially cover the window and/or door openings in the vehicle body adjacent the front and rear seat occupant positions. Although restraint curtain 36 is described and depicted herein as being an inflatable airbag, it is to be understood that the invention may also be practiced with a non-inflatable curtain of the type well known in the vehicle occupant restraint field. Figure 2 depicts the restraint curtain 36 in a deflated and stowed condition wherein it is rolled into a compact spiral configuration and secured in a position extending along the roof rail 32. For inflation purposes, a gas generator 38 is located adjacent the stowed restraint curtain 36 in the roof rail 32 and is connected thereto by a conduit 40. The stowed restraint curtain 36 and the gas generator 38 are both housed within a compartment located behind the headliner trim panel 41 (see Figs. 4 and 5), so as to be hidden from view. As best seen in Fig. 1, a slit 42 extends generally vertically upward from the lower edge of the restraint curtain 36 toward the upper edge thereof, dividing the restraint curtain into a first or forward section 36a and a second or rear section 36b. A connecting member 44 (see Figure 3) is attached to the restraint curtain 36 adjacent its lower edge and spans the slit 42 to connect the first and second sections. The connecting member 44 may be formed of a rigid material such as plastic or metal, or it may be a flexible material. A guide track 46 is mounted to the inner surface of the C-pillar 22 and extends generally vertically at a position generally coinciding with the location of the slit 42 when the curtain 36 is in the deployed condition (see Figure 3). As seen in Figure 6, the guide track is hidden behind a pillar trim panel 56 and has a slot 48 oriented toward the forward end of the vehicle. A slide member 50 is retained in the slot 48 for vertical sliding movement along the guide rail. A flexible tether 52 has a first end attached to the slide member 50 and a second end attached to a ring 54. The ring 54 encircles the connecting member 44 as best seen in Figure 3, so that the connecting member 44 is free to rotate relative to the ring and the tether 52. When in the stowed condition, the restraint curtain 36 is rolled into a spiral by rolling the lower edge upwardly toward the upper edge of the curtain 36. See Figure 4. The curtain 36 is rolled in a direction parallel with the slit 42 so that the connecting member 44 is exposed through the slit 42 and the ring 54 may remain attached to the connecting member 44 without the tether 52 becoming rolled up within the curtain 36. With the restraint curtain 36 in the stowed condition, the slide member 50 is positioned at the extreme upper end of the guide track 46 and the tether 52 extends to the connecting member 44 as seen in Figs. 2 and 4. Guide means, such as a ramp 57 (see Figure 4), may be provided directly below the stowed restraint curtain 36 to direct the restraint curtain 36 in the proper direction as it unrolls to the deployed condition. The headliner trim panel 41 and the pillar trim panel 56 are preferably formed of a flexible, resilient material such as plastic, and are secured to the roof 30 and pillar 22 respectively in a known manner, not shown. The lower end of the headliner trim panel 41 overlaps the upper end of the pillar trim panel 56 by a small amount as seen in Figure 4 to present a clean, finished appearance within the passenger compartment. As best seen in Fig. 6, the pillar trim panel 56 extends over the guide track 46 to conceal it from view by occupants of the passenger compartment. The slide member 50 and/or the tether 52 project out from behind the pillar trim panel 56 to allow connection of the ring 54 to the connecting member 44. When the restraint system is triggered during a rollover or side impact event, the restraint curtain 36 is inflated and begins to unroll to its deployed condition. The expanding curtain 36 forces the headliner trim panel 41 past the upper end of the pillar trim panel 56, thus opening a seam through which the restraint curtain 36 may deploy downwardly and over the surface of the pillar trim panel. As the restraint curtain 36 is inflated and unrolls to its deployed condition, the connecting member 44 moves downwardly and is held close to the pillar trim panel 56 by the tether 52. Downward movement of the connecting member 44 urges the tether 52 and slide member 50 downwardly along the guide track 46 until the restraint curtain 36 is fully deployed and the slide member 50 is adjacent the lower end of the guide track 46. During deployment of the curtain 36, the connecting member 44 rotates freely within the ring 54 and so does not interfere in any way with unrolling of the curtain 36. Although Figures 1-6 depict the restraint curtain 36 tethered to the C-pillar 22 of a vehicle, the present invention may just as readily be practiced by tethering the curtain 36 to the A-pillar 18, the B-pillar 20, or any other structure forming or adjacent to the side wall 12 of the vehicle as may be required depending upon the interior configuration of the vehicle and the desired nature of the occupant restraint system. Figure 7 depicts an alternative embodiment of an occupant restraint system wherein a curtain 36' has first and second slits 72a,72b. First and second guide tracks 60a,60b extend vertically along the pillar 22 at spaced locations. Slide members 62a,62b engage respective guide tracks 60a,60b and first and second tethers 64a,64b extend between the curtain 36' and the respective slide members. In the embodiment of the invention shown in Figure 7, the two guide tracks 60a,60b are disposed adjacent opposite edges of the pillar 22 and are covered by a pillar trim panel 56. Each tether 64a,64b is attached to the restraint curtain 36' by means of a ring 68a,68b surrounding a connecting member 70a,70b spanning slits 72a,72b in the curtain, in a manner generally similar to that described in connection with Figures 1-5 above. Alternatively, the tethers 64a,64b may be attached to the lower edge of the restraint curtain 36' in a more conventional fashion, thus eliminating the connecting members 70a,70b and the rings 68a,68b. The use of two guide tracks engaging the restraint curtain at two spaced-apart points provides a more positive and secure positioning of the restraint curtain during deployment and when in the fully deployed condition. Figures 8-10 illustrate a method of rolling a restraint curtain 80 so that a tether 82 attached directly to the lower edge 80a remains exposed on the outside of the roll when in the stowed condition. In the first step of the rolling process, the lower edge 80a of the curtain 80 is brought up to the upper edge 80b, folding the curtain generally in half to form a crease 84 at the new lower end of the curtain and place the tether 82 adjacent the upper edge 80b. The curtain 80 is then rolled in a spiral fashion, starting at the crease edge 84 and rolling upwardly toward the upper and lower edges 80b,80a. Additional tethers, cords, or similar members (not shown) may also be attached to the curtain 80 adjacent its forward and/or the rear lower corners as desired. The rolled curtain 80 is mounted adjacent the roof rail 32 with the curtain rolled inwardly, toward the pillar 22 and the tether 82 to the outboard side of the passenger compartment. The upper edge 80b is secured to the vehicle and the tether 82 is attached to a guide track 46, or to some other appropriate tether-tensioning device (not shown). The curtain 80 is then in a quick-deploying "roll fold" configuration with the tether 82 exposed on the outside of curtain when in the stowed condition. Accordingly, the tether 82 may be kept very short so that the tether holds the lower edge 80a of the curtain 80 close to the side wall of the vehicle during and after deployment and throughout the deployment sequence without the need for the slit curtain and connecting member disclosed in the first embodiment of the invention. Various other modifications and variations are possible and this disclosure should thus be considered illustrative and the scope of the invention is defined by the appended claims.

Claims: An occupant restraint system for an automotive vehicle (10) having a roof (30) and a pillar (22) extending downwardly from the roof (30) to define a lateral edge of an opening, the system comprising an occupant restraint curtain (36) having a first edge securable to the roof (30) adjacent an upper edge of the opening and an opposite second edge, the curtain (30) is movable between a stowed condition wherein the curtain is retained adjacent the roof and a deployed condition wherein the curtain is generally planar and extends downwardly from the roof (30) to cover at least a portion of the opening, the curtain (36) comprising first and second sections (36a, 36b) separated by a slit (42)extending from the second edge toward the first edge, a connecting member (44) attached to the curtain adjacent the second edge thereof to span the slit (42) and connect the first and second sections (36a and 36b), characterized in that the system further comprises a tether (52) having a first end engageable with the pillar (22) for movement therealong when the curtain (36) moves between the stowed and deployed conditions, the tether (52) having a second end rotatably engaged with the connecting member (44) whereby the connecting member (44) is free to rotate relative to the tether (52) as the curtain (36) moves between the stowed condition and the deployed condition. An occupant restraint system as claimed in claim 1 wherein the first edge of the curtain (36) is securable to a roof rail (32) extending generally parallel to the upper edge of the opening. An occupant restraint system as claimed in claim 1 or in claim 2 wherein the stowed condition is achieved by rolling the second edge of the curtain (36) towards the first edge of the curtain. An occupant restraint system as claimed in any of claims 1 to 3 wherein the curtain is an airbag (36) that is inflated to deploy the airbag (36). An occupant restraint system as claimed in any of claims 1 to 4 wherein the connecting member (44) is rigid. An occupant restraint system as claimed in any of claims 1 to 5 wherein the system further comprises a ring (54) connected to the second end of the tether (52) and encircling the connecting member (44). An occupant restraint system as claimed in any of claims 1 to 6 wherein the system further comprises a guide track (46) extending along the pillar (22) for engagement with the first end of the tether (52). An occupant restraint system as claimed in any of claims 1 to 7 wherein the curtain (36) has a second slit (72b) extending generally parallel to the first slit (72a), and further comprises a second connecting member (70b) attached to the curtain (36) adjacent the second edge thereof to span the second slit (72b) and a second tether (64b) having a first end engageable with the pillar (22) for movement therealong when the curtain (36) moves between the stowed and deployed conditions, the second tether (64b) having a second end rotatably engaged with the second connecting member (70b) whereby the second connecting member (70b) is free to rotate relative to the second tether (64b) as the curtain (36) moves between the stowed condition and the deployed condition. A method of securing an occupant restraint curtain in an automotive vehicle (10) having a roof (30) defining an upper edge of an opening and a pillar (22) extending downwardly from the roof (30) to define a lateral edge of the opening, the method comprising the steps of providing an occupant restraint curtain (36) comprising first and second sections (36a and 36b) separated by a slit (42) extending from a first edge of the curtain toward an opposite second edge of the curtain (36), and a connecting member (44) attached to the curtain (36) adjacent the first edge thereof to span the slit (42) and connect the first and second sections (36a and 36b), characterised in that the method further comprises the steps of rolling the first edge of the curtain toward the second edge such that the connecting member (44) remains accessible through the slit (42), securing the second edge of the curtain (36) to the vehicle (10) adjacent the top edge of the opening, attaching a first end of a tether (52) to the pillar (22) for movement therealong, and rotatably engaging a second end of the tether (52) with the connecting member (44) whereby the connecting member is free to rotate with respect to the tether (52) as the curtain (36) moves between the stowed and the deployed positions. A method as claimed in claim 9 wherein the step of attaching a first end of the tether (52) to the pillar (22) comprises engaging the first end of the tether (52) with a guide track (46) extending along the pillar(22).

Inventors: BALAVICH KAREN M, BROWN JOSEPH ROBERT, ZYCHOWICZ JULIE ANN, BALAVICH, KAREN M., BROWN, JOSEPH ROBERT, ZYCHOWICZ, JULIE ANN
Applicants: FORD GLOBAL TECH INC, FORD GLOBAL TECHNOLOGIES, INC.
Application year: 2001
Main classification: B60R21
IPC codes: B60R21