Abstract:
An airbag for protecting a vehicle occupant. The airbag includes an inner panel and an outer panel connected to form an inflatable chamber. The airbag includes a cloth sealing element connecting the periphery of the inner and outer panels; wherein the sealing element is located both inside and outside of the inflatable chamber; and wherein certain yarns from the sealing element are located entirely within the inflatable chamber. The airbag may include a cloth connecting element connected to the inner and outer panels at a position away from the periphery of the panels to thereby form a non-inflatable region located within the inflatable chamber.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims priority to and the benefit of U.S. Provisional Application No. 60/537,917, filed Jan. 22, 2004. 
     
    
     BACKGROUND  
       [0002]     The present invention relates to an airbag for protecting an occupant of a vehicle. In particular, the present invention relates to an airbag that is suitably used as a curtain type airbag configured to deploy along the side of the vehicle interiorAn exemplary curtain type airbag is disclosed in U.S. Pat. No. 6,318,753 (incorporated by reference herein in its entirety).  
       SUMMARY OF THE INVENTION  
       [0003]     According to an embodiment of the present invention, a curtain type airbag for protecting an occupant of the vehicle is provided. The airbag includes outer and inner panels. The inner panel is positioned on the occupant side of the airbag. The inner and outer panels may connected by a connecting element and/or a sealing element.  
         [0004]     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]     These and other features, aspects and advantages of the present invention will become apparent from the following description, appended claims, and the accompanying exemplary embodiments shown in the drawings, which are briefly described below.  
         [0006]      FIG. 1  is a side view of a curtain type airbag according to an embodiment of the present invention.  
         [0007]      FIG. 2  is a sectional view of an embodiment of the present invention taken along line a-a in  FIG. 1 .  
         [0008]      FIG. 3  is a sectional view of an alternative embodiment of the present invention taken along line a-a in  FIG. 1 .  
         [0009]      FIG. 4  is a sectional view of an exterior seam of a curtain airbag such as disclosed in Japanese Patent Publication JP4-356249.  
         [0010]      FIG. 5  is a sectional view of an embodiment of the present invention taken along line b-b in  FIG. 1 .  
         [0011]      FIG. 6  is a sectional view of yet another embodiment of the present invention taken along line b-b in  FIG. 1 .  
         [0012]      FIG. 7  is a sectional view of yet another embodiment of the present invention taken along line b-b in  FIG. 1 .  
         [0013]      FIG. 8  is a sectional view of yet another embodiment of the present invention taken along line b-b in  FIG. 1 .  
         [0014]      FIG. 9  is a sectional view of yet another embodiment of the present invention taken along line b-b in  FIG. 1 .  
         [0015]      FIG. 10  is a sectional view of yet another embodiment of the present invention taken along line b-b in  FIG. 1 .  
         [0016]      FIG. 11  is a perspective illustration of a fabric reinforcement tape according to an embodiment of the invention;  
         [0017]      FIGS. 12A and 12B  are cross-sectional views taken along II-II of embodiments of the fabric reinforcement tape of  FIG. 11 ;  
         [0018]      FIG. 13  is a perspective illustration of a fabric reinforcement tape according to another embodiment of the invention;  
         [0019]      FIGS. 14A and 14B  are cross-sectional views taken along IV-IV of embodiments of the fabric reinforcement tape of  FIG. 13 ; and 
     
    
     DETAILED DESCRIPTION  
       [0020]     Embodiments of the present invention will be described in detail below with reference to the drawings.  
         [0021]     As shown in  FIG. 1 , according to an embodiment of the present invention, a passenger-side air bag includes  100  an inner panel  110  and an outer fabric panel  120 . The panels may be connected along their peripheries. The upper edge of the air bag includes a sewn seam  140 . The air bag  100  may also include an internal seam or seams  130  to divide the inflatable portion of the air bag into separate sections or cells. A gas generator (not shown) may be provided to supply inflation gas to the air bag.  
         [0022]     Preferably, the present invention is directed to curtain type air bags. A curtain air bag is typically mounted along the side of vehicle and is configured to deploy downward from a vehicle roof rail between the occupants of the vehicle and the windows. The curtain type air bags protect a vehicle occupant during a side collision and vehicle rollover situation. Thus, the curtain must remain inflated for an extended period in order to protect the occupant. As a result, leakage of inflation gas from the air bag must be addressed. Leakage of inflation gas through the seams and connections between the panels of the airbag is of particular concern.  
         [0023]     An exemplary connection between the airbag panels is shown in  FIG. 4 .  FIG. 4  discloses an exterior seam  440  connecting an inner panel  410  and an outer panel  420  of a curtain airbag. The connection structure  440  includes a sewn seam  415  connecting the air bag panels. The exterior of the connection structure along the sewn seam  415  is coated with a sealant  450  in order to reduce gas leakage the seam  415 . The interior of the connection structure is covered by a tape  500 . Another typical connection structure for connecting the periphery of curtain air bag panels is disclosed in JP4-356249 (incorporated by reference herein it its entirety).  
         [0024]     As shown in  FIG. 2 , according to an embodiment of the present invention, the airbag includes a sealing element  200 . The sealing element  200  may comprise a cloth or tape material. The sealing element  200  preferably is forked so that each branch of the fork  205 ,  215  may be connected to one of the inner and outer panels. The stem  225  of the fork-shaped sealing element extends outwardly away from the interior of the airbag past the periphery of the inner and outer fabric panels.  
         [0025]     Preferably, the sealing element  200  is connected to the fabric panels by an adhesive  300  in order to eliminate the requirement for stitching. However, the scope of the present invention includes connecting the sealing element to the fabric panel by other suitable means such as, for example, sewing, weaving, and RF welding. The sealing element increases the gas permeability of the airbag by reducing the gas leakage through conventionally stitched periphery seams that are used to connect fabric panels. Furthermore, as shown in  FIG. 1 , the sealing element may include a positioning hole(s)  150 . The positioning holes  150  are used to properly align the airbag material during the production process.  
         [0026]      FIG. 3  discloses an alternative embodiment of the present invention. As shown in  FIG. 3 , the sealing connection may include both a fork-shaped cloth  200  and a further reinforcing tape  500 . The tape  500  provides a second barrier against escaping gas and further supports the fork shaped cloth to reduce the likelihood of a separation of the panels along the peripheries of the airbag  100 .  
         [0027]      FIG. 1  also discloses that the inner and outer panels may include connected portions  130  located a distance away from the peripheries of the panels. U.S. Pat. No. 6,489,006 (incorporated by reference herein) discloses one example of a structure for connecting airbag fabric panels together.  
         [0028]     The present invention also includes connecting interior portions of the airbag panels together to form inflatable cells or regions. As shown in  FIG. 5 , a connecting element  600  is provided. The connecting element  600  preferably comprises a gas tight cloth. Alternatively, the connecting element may comprise a coated fabric material such as a silicone coated fabric. In yet another alternative, the connecting element  600  may comprise a sealing tape.  
         [0029]     The connecting element is connected to both the inner fabric panel  110  and outer fabric panels  120 . The connecting element  600  restricts separation of the panels  110 ,  120  and prevents gas flow, to thereby form inflation regions or cells. The connecting element may take any suitable shape. For example, as shown in  FIG. 5 , the connecting element  600  may include fork-shaped ends  610 . Each of the four branches of the connecting element may be connected to one of the two fabric panels.  
         [0030]     Preferably, the connecting element is connected to the fabric panels by an adhesive  300  in order to eliminate the requirement for stitching. However, the scope of the present invention includes connecting the sealing element to the fabric panel by other suitable means such as, for example, sewing, weaving, and RF welding.  
         [0031]      FIG. 6  discloses yet another alternative of the present invention. As shown in  FIG. 6 , the connecting element  700  may have a generally rectangular in cross-section with protruding branches  705  for connecting to the fabric panels. The airbag according to the embodiment of the present invention shown in  FIG. 6  may also include a non-inflatable region  170  between the branches of the connecting element. The non-inflatable region  170  may include an opening  175  that passes through the connecting element and both fabric panels. The opening or positioning hole  175  may be used to properly align the airbag material during the production process.  
         [0032]     As shown in  FIG. 7 , an alternative embodiment of the present invention includes a connecting element  800  for connecting the inner fabric panel  110  with the outer fabric panel  120 . The connecting element  800  may include a first connecting cloth  810  and a second connecting cloth  820 . The connecting cloths  810 ,  820  intersect to form an X-shaped connecting element  800 . The connecting cloths  810 ,  820  may be coated on one of both sides with a sealing material such as, for example, silicone.  
         [0033]     Preferably, the connecting element  800  is connected to the fabric panels by an adhesive  300  in order to eliminate the requirement for stitching. However, the scope of the present invention includes connecting the sealing element to the fabric panel by other suitable means such as, for example, sewing, weaving, and RF welding.  
         [0034]     Each of the connecting cloths  810 ,  820  include warp and weft yarns. Depending on the orientation of the connecting cloths either the warp or the weft yarns extend through the connecting element. For example, according to one embodiment of the present invention, the warp yarns extend from one end  811  to another end  812  of the first connecting cloth  810 . Similarly, the warp yarns extend from one end  821  to another end  822  of the second connecting cloth  820 .  
         [0035]     According to an embodiment of the present invention, a portion of the warp yarns extend from one end  811  of the first connecting cloth  810  to the other end  822  of the second connecting cloth  820 . Similarly, a portion of the warp yarns extend from one end  821  of the second connecting cloth  820  to the other end  812  of the first connecting cloth  810 . Preferably, the number of yarns extend from one connecting cloth to the other connecting cloth (e.g., from a first end  811  of the first connecting cloth  810  to another end  822  of the second connecting cloth  820 ) is less than the number of yarns extending within the same connecting cloth. As mentioned above, the aforementioned description of the intertwining of the warp yarns is exemplary, the scope of the present invention could include a similar arrangement for the weft yams, depending on the orientation of the connecting cloths.  
         [0036]     As shown in  FIG. 8 , an alternative embodiment of the present invention includes a connecting element  900  for connecting the inner fabric panel  110  with the outer fabric panel  120 . The connecting element  900  may include a first connecting cloth  910  and a second connecting cloth  920 . The connecting cloths may be coated on one of both sides with a sealing material such as, for example, silicone.  
         [0037]     The yarns from the connecting cloths  910 ,  920  intersect to form a single layer planar region  923 . The yams extending from one end  911  of the first connecting cloth  910  pass through the planar region  923  and extend to a second end  912  of the first connecting cloth  910 . Similarly, the yarns from one end  921  of the second connecting cloth  920  extend through the planar region  923  and extend to a second end  922  of the second connecting cloth.  
         [0038]     Preferably, the connecting element  900  is connected to the fabric panels by an adhesive  300  in order to eliminate the requirement for stitching. However, the scope of the present invention includes connecting the sealing element to the fabric panel by other suitable means such as, for example, sewing, weaving, and RF welding.  
         [0039]     The non-inflatable region  170  of the airbag includes the planar region  923  and may include an opening  175  that passes through the planar region  923  and both fabric panels. The opening or positioning hole  175  may be used to properly align the airbag material during the production process.  
         [0040]     As shown in  FIG. 9 , an alternative embodiment of the present invention includes a connecting element  950  for connecting the inner fabric panel  110  with the outer fabric panel  120 . The connecting element  950  may include a first connecting cloth  960  and a second connecting cloth  970 . The connecting cloths may be coated on one of both sides with a sealing material such as, for example, silicone.  
         [0041]     The yarns from the connecting cloths  960 ,  970  intersect to form a single layer planar region  980 . Yarns extend from one end  961  of the first connecting cloth  960  pass through the planar region  980  and extend to a second end  972  of the first connecting cloth  910 . In addition, yarns from one end  961  of the first connecting cloth  960  extend to a second end  972  of the second connecting cloth  970 . Similarly, yarns extend from one end  971  of the second connecting cloth  970  pass through the planar region  980  and extend to a second end  972  of the second connecting cloth  970 . In addition, yarns from one end  971  of the second connecting cloth  970  extend to a second end  972  of the second connecting cloth  970 .  
         [0042]     Preferably, the connecting element  950  is connected to the fabric panels by an adhesive  300  in order to eliminate the requirement for stitching. However, the scope of the present invention includes connecting the sealing element to the fabric panel by other suitable means such as, for example, sewing, weaving, and RF welding.  
         [0043]     The non-inflatable region  170  of the airbag includes the planar region  980  and may include an opening  175  that passes through the planar region  980  and both fabric panels. The opening or positioning hole  175  may be used to properly align the airbag material during the production process.  
         [0044]     As shown in  FIG. 10 , according to an embodiment of the present invention, the airbag includes a sealing element  250 . The sealing element  250  is positioned to seal the periphery of the air bag. The sealing element may comprise a cloth material. The sealing element  250  discloses two intertwined sealing cloths  260 ,  270 . The sealing cloths  260 ,  270  intersect to form the X-shaped connecting element  250 .  
         [0045]     Preferably, the sealing element  250  is connected to the fabric panels by an adhesive  300  in order to eliminate the requirement for stitching. However, the scope of the present invention includes connecting the sealing element to the fabric panel by other suitable means such as, for example, sewing, weaving, and RF welding.  
         [0046]     Each of the sealing cloths  260 ,  270  include warp and weft yarns. Depending on the orientation of the sealing cloths either the warp or the weft yams extend through the sealing element. For example, according to one embodiment of the present invention, the warp yams extend from one end  261  to another end  262  of the first sealing cloth  260 . Similarly, the warp yarns extend from one end  271  to another end  272  of the second sealing cloth  270 .  
         [0047]     According to an embodiment of the present invention, a portion of the warp yarns extend from one end  261  of the first sealing cloth  260  to one end  271  of the second sealing cloth  820 . Similarly, a portion of the warp yarns extend from one end  271  of the second sealing cloth  270  to one end of the first sealing cloth  260 . Preferably, the number of yarns extend from one sealing cloth to the other sealing cloth (e.g., from a first end  261  of the first sealing cloth  260  to a first end  271  of the second sealing cloth  270 ) is greater than the number of yarns extending within the same sealing cloth. As a result the is more sealing cloth located in the inflatable portion of the airbag. As mentioned above, the aforementioned description of the intertwining of the warp yarns is exemplary, the scope of the present invention could include a similar arrangement for the weft yarns, depending on the orientation of the sealing cloths.  
         [0048]     The sealing element increases the gas permeability of the airbag by reducing the gas leakage through conventionally stitched periphery seams that are used to connect fabric panels. Furthermore, as shown in  FIG. 10 , the sealing element  250  may include a positioning hole(s)  150 . The positioning holes  150  are used to properly align the airbag material during the production process.  
         [0049]     According to an embodiment of the present invention, a curtain type airbag may include a peripheral sealing element and/or an internal connecting element. The scope of the present invention further includes providing a plurality of sealing elements in a curtain airbag. Similarly, the scope of the present invention includes providing multiple connecting elements so that multiple inflatable portions of cells may be provided in an airbag.  
         [0050]      FIGS. 11-15  disclose various embodiments of connecting and sealing element for use with airbags  100  having two panels  110 ,  120  such as described above. For example, although not shown in the drawings, adhesive  300  may also be provided to connect the below described connecting element to the airbag panels.  
         [0051]     Referring to  FIG. 11 , an alternative embodiment of the connecting element  10  is illustrated. The illustrated embodiment of the connecting element  10  includes four flaps, such as flap  11  extending from an intersection  12 . In a preferred embodiment, each flap extends at least 1 mm from the intersection. Most preferably, the flaps extend about 15 mm from the intersection.  
         [0052]     When the connecting element  10  is implemented for reinforcing a fabric seam, for example, each flap engages one surface of the pair of fabric segments forming the seam. Two such configurations are illustrated in  FIGS. 15A and 15B  and are described below in greater detail.  
         [0053]     Referring now to  FIGS. 12A and 12B , embodiments of the weaved structure of the connecting element.  FIG. 12A  is a cross-sectional view of one weaved configuration of a connecting element similar to that illustrated in  FIG. 11 . The weaved configuration of the connecting element  20  includes a vertical weft arrangement  21  and a horizontal weft arrangement  22  that form the four flaps of the connecting element. The vertical weft arrangement  21  extends through the intersection  26  to form the two opposing vertical flaps of the connecting element  20 . Similarly, the horizontal weft arrangement  22  extends through the intersection  26  to form the two opposing horizontal flaps.  
         [0054]     The vertical weft arrangement  21  is formed by a plurality of weft threads  23 . Similarly, the horizontal weft arrangement  22  is formed by a plurality of weft threads  24 . The weft threads  23 ,  24  are interlaced with warp threads  25  therebetween. The warp threads  25  extend in a longitudinal direction of the connecting element, the longitudinal direction being perpendicular to the plane of the weft arrangements  21 ,  22 .  
         [0055]     In the embodiment illustrated in  FIG. 12A , all weft threads  25  of a particular flap extend through the intersection  26  to the opposing flap. Thus, the weft thread  23  extends through the intersection  26  to each of the opposing vertical flaps. Similarly, the weft thread  24  extends through the intersection  26  to each of the opposing horizontal flaps.  
         [0056]     Preferably, the free ends  27  of each flap are resistant to unraveling. This may be achieved in any of a number of ways commonly known to those skilled in the art. For example, a separate stitching in the longitudinal direction of the tape  20  may be provided along the free end  27  of each flap to prevent unraveling.  
         [0057]     It will be understood by those skilled in the art that while the figures illustrate the weft arrangement of each flap having only a few cycles and few warp threads interlaced therebetween, any number and density of weft cycles and warp threads may be used. Preferably, each flap is at least 1 mm in length and includes at least 5 weft cycles and warp threads. Most preferably, each flap is about 15 mm in length and includes about 7 weft cycles and warp threads.  
         [0058]     Referring now to  FIG. 12B , a variation of the weave configuration illustrated in  FIG. 12A  will now be described. The weave configuration of the connecting element  30  is similar to that of the connecting element  20  in  FIG. 12A  and includes a vertical weft arrangement  31  and a horizontal weft arrangement  32 . The weft arrangements  31 ,  32  include weft threads with warp threads interlaced therebetween. In the embodiment illustrated in  FIG. 12B , the weft threads of a particular flap do not extend to the opposing flap. Rather, as illustrated in the detailed view in  FIG. 12B , the weft threads of each flap separate at the intersection and extend to each of the adjacent flaps. Thus, the weft arrangement of the left flap includes weft threads  33 ,  34 . One weft thread  33  extends through the intersection to the adjacent flap extending downward, while the other weft thread  34  extends through the intersection to the adjacent flap extending upward. Thus, the flap extending upward has a weft arrangement which includes the weft thread  34  from the left flap and another weft thread  35 . The weft thread  35  extends through the intersection to the adjacent flap extending rightward.  
         [0059]     Referring now to  FIG. 13 , a connecting element according to another embodiment of the present invention is illustrated. The illustrated connecting element  40  is similar to the connecting element  10  shown in  FIG. 11  in that the connecting element  40  is provided with four flaps, such as flap  41  extending outwardly. Unlike the embodiment of  FIG. 11 , the tape  40  of  FIG. 13  includes a central region  42  having a filler  43  configured as a cylinder with its axis aligned with the longitudinal axis of the connecting element  40 .  
         [0060]      FIGS. 14A and 14B  illustrate cross-sectional views of embodiments of weave configurations for the tape illustrated in  FIG. 13 . Referring now to  FIG. 14A , the weave configuration of the connecting element  50  includes a vertical weft arrangement  51  and a horizontal weft arrangement  52  that form the four flaps of the connecting element  50 . The vertical weft arrangement  51  extends around the central region  56  to form the two opposing vertical flaps of the connecting element  50 . Similarly, the horizontal weft arrangement  52  extends around the central region  56  to form the two opposing horizontal flaps.  
         [0061]     The vertical weft arrangement  51  is formed by a plurality of weft threads  53 . Similarly, the horizontal weft arrangement  52  is formed by a plurality of weft threads  54 . The weft threads  53 ,  54  are interlaced with warp threads  55  therebetween.  
         [0062]     In the embodiment illustrated in  FIG. 14A , all weft threads  53 ,  54  of a particular flap extend around the central region  56  to the opposing flap. In extending around the central region  56 , the weft threads of each flap may separate. For example, the two threads forming the weft arrangement  51  separate, with each thread extending around a different side of the central region  56 , and rejoin on the opposing flap side of the central region  56 . At the central region  56 , the weft threads may be interlaced with either the filler  57 , a central thread (not shown), or the other weft threads.  
         [0063]     The filler  57  may include any number of materials. For example, the filler  57  may be formed of a textile material such as wool, or it may be made of a solid rubber or soft plastic material.  
         [0064]     Referring now to  FIG. 14B , a variation of the weave configuration illustrated in  FIG. 14A  will now be described. The weave configuration of the connecting element  60  is similar to that of the connecting element  50  in  FIG. 14A  and includes a vertical weft arrangement  61  and a horizontal weft arrangement  62 . The weft arrangements  61 ,  62  include weft threads with warp threads interlaced therebetween. In the embodiment illustrated in  FIG. 14B , the weft threads of a particular flap do not extend to the opposing flap. Rather, similar to the embodiment of  FIG. 12B , the weft threads of each flap separate at the central region  66  and extend to each of the adjacent flaps. Thus, the weft arrangement of the left flap includes weft threads  63 ,  64 . One weft thread  63  extends around the central region  66  to the adjacent flap extending downward, while the other weft thread  64  extends around the central region  66  to the adjacent flap extending upward. Thus, the flap extending upward has a weft arrangement which includes the weft thread  64  from the left flap and another weft thread.  
         [0065]     Given the disclosure of the present invention, one versed in the art would appreciate that there may be other embodiments and modifications within the scope and spirit of the invention. Accordingly, all modifications attainable by one versed in the art from the present disclosure within the scope and spirit of the present invention are to be included as further embodiments of the present invention.