Airbag with enhanced gas diffuser

1. An improved airbag assembly ( 20 ) comprising:

an inflator ( 40 ) for providing a source of inflation gas;

an airbag, the airbag ( 20 ) having a first end, a second end and a first side and a second side extending between said ends defining the airbag ( 20 ) configured with one or more inflatable chambers ( 61 );

a diffuser ( 70 ) having an inlet for receiving the inflator ( 40 ) and one or more discharge openings ( 82 a , 82 b ) to fill the one or more inflatable chambers ( 61 ), the diffuser ( 70 ) being affixed internal of the airbag ( 20 ), the diffuser ( 70 ) being formed from at least two separate layers of fabric, at least one folded inner and at least one folded outer pocket layers ( 71 , 73 ) of fabric, and sewn or otherwise affixed to the airbag ( 20 ); wherein at least one layer ( 71 ) of the diffuser ( 70 ) has a seamless fold ( 75 ) at the attachment to the airbag ( 20 ) where the diffuser ( 70 ) is sewn to the airbag ( 20 ) or otherwise affixed; and

wherein the folded inner pocket layer ( 71 ) is configured to fit inside the outer pocket layer ( 73 ) forming a two-layer structure and the fold ( 75 ) in the inner layer ( 71 ) is oriented in a first direction relative to the fabric and a fold ( 77 ) of the outer layer ( 73 ) is oriented in a second direction relative to the fabric wherein the second direction of the outer layer ( 73 ) is different from the first direction of the inner layer ( 71 ) wherein the fold ( 75 ) of the inner pocket layer ( 71 ) and the fold ( 77 ) of the outer pocket layer ( 73 ) each align with a stitched seam of the other pocket layer, respectively to form one seamless layer and one stitched seam where the diffuser ( 70 ) is sewn to the airbag ( 20 ) wherein the fold ( 75 or 77 ) forming the seamless layer of one pocket layer ( 71 or 73 ) underlies or overlies the other pocket layer to form two layers, a layer of seamless fabric and a layer of seamed fabric along an entire length of the diffuser ( 70 ) at an attachment to the airbag ( 20 ) at a top seam, and the first direction and second direction of folds being inclined relative to the other so upon assembly the inner pocket layer fold ( 75 ) is directionally inclined on a bias relative to the outer pocket layer fold ( 77 ).

2. The improved airbag assembly ( 20 ) of claim 1 wherein the pocket layers ( 71 , 73 ) of the diffuser ( 70 ) have a seamless fold at the attachment of the airbag ( 20 ) where sewn to the airbag ( 20 ) or otherwise affixed.

3. The improved airbag assembly ( 20 ) of claim 1 wherein the diffuser ( 70 ) has the two inner and outer pocket layers ( 71 , 73 ) sewn together in one or more locations spaced from the fold ( 75 ) and has unsewn panel portions forming an inlet neck ( 72 ) and the one or more discharge openings ( 82 a , 82 b ).

4. The improved airbag assembly ( 20 ) of claim 3 wherein adjacent the fold ( 75 ) at the inlet neck ( 72 ) for receiving the inflator ( 40 ) has the inner pocket layer ( 71 ) sewn to the outer pocket layer ( 73 ) in a path at least partially parallel to the attachment to the airbag ( 20 ) to form a pocket into which the inflator ( 40 ) is inserted.

5. The improved airbag assembly ( 20 ) of claim 4 wherein the path extends to a turn and forms a “U” shape sewn seam below the inlet neck ( 72 ) and above one of the discharge openings ( 82 a , 82 b ).

6. A diffuser ( 70 ) for an airbag ( 20 ) comprises:

an inner pocket layer ( 71 ), the inner pocket layer ( 71 ) being a piece of fabric having a fold ( 75 ) along an edge, the edge has a stitched seam ( 78 ) adjacent the fold ( 75 );

an outer pocket layer ( 73 ), the outer pocket layer ( 73 ) being a separate piece of fabric having a fold ( 77 ) along an edge, the edge has a stitched seam ( 78 ) adjacent the fold ( 77 ); and

wherein the inner pocket layer ( 71 ) is positioned inside the outer pocket layer ( 73 ) to form the diffuser ( 70 ), respective folds ( 75 , 77 ) are located under or over the respective stitched seam ( 78 ) of the other pocket layer ( 71 or 73 ) to create a continuous length of seamless layer across the diffuser ( 70 ) at a location where the diffuser ( 70 ) will be attached to the airbag ( 20 ), wherein the fold ( 75 ) of the inner pocket layer ( 71 ) is oriented in a first direction relative to the fabric of inner pocket layer ( 71 ) and the fold ( 77 ) of the outer pocket layer ( 73 ) is oriented in a second direction relative to the fabric of outer pocket layer ( 73 ) wherein the second direction is different from the first direction, each fold ( 75 , 77 ) aligns with a stitched seam ( 78 ) of the other pocket layer ( 71 or 73 ) to form one seamless layer and one stitched seam at a location where the diffuser ( 70 ) is to be sewn to a curtain airbag ( 20 ).

7. The diffuser ( 70 ) for an airbag ( 20 ) of claim 6 wherein the diffuser ( 70 ) has the two inner and outer pocket layers ( 71 , 73 ) sewn together in one or more locations below or spaced from the folds ( 75 , 77 ) and has unsewn panel portions forming an inlet ( 72 ) and one or more discharge openings ( 82 a , 82 b ).

8. The diffuser ( 70 ) for an airbag ( 20 ) of claim 6 wherein below or adjacent the folds ( 75 , 77 ), the diffuser ( 70 ) has the inlet ( 72 ) for receiving an inflator ( 40 ) and has the inner pocket layer ( 71 ) sewn to the outer pocket layer ( 73 ) in a path at least partially parallel to the attachment to the airbag ( 20 ) to form the inlet ( 72 ) a into which the inflator ( 40 ) is inserted.

9. The diffuser ( 70 ) for an airbag ( 20 ) of claim 8 wherein the path extends to a turn and forms a “U” shape sewn seam below the inlet ( 72 ) and above one of the discharge openings ( 82 a , 82 b ).

10. A method of manufacturing a two-layer fabric diffuser ( 70 ) comprises the steps of:

cutting an inner pocket fabric layer ( 71 ) from a first piece of fabric;

folding the inner fabric layer ( 71 ) to form an edge or fold ( 75 ) with a seamless portion and sewing a portion of the inner pocket fabric layer together up to the fold ( 75 ) which forms the seamless portion;

cutting an outer pocket fabric layer ( 73 ) from a second separate piece of fabric;

folding the outer fabric layer ( 73 ) to form an edge or fold ( 77 ) with a seamless portion and sewing a portion of the outer pocket fabric layer ( 73 ) together up to the fold ( 77 ) which forms the seamless portion;

inserting the folded inner pocket layer ( 71 ) into the folded outer pocket layer ( 73 ) to form an assembly;

sewing a bottom seam ( 78 ) on the assembly forming one or more discharge openings ( 82 a , 82 b ), discharge opening ( 82 b ) between the edge or fold ( 75 ) and the bottom seam ( 78 );

sewing a “U” shaped inlet seam ( 78 ) below the edge or fold ( 77 ) to form an inlet ( 72 , 90 ) for receiving an inflator ( 40 ), the “U” shaped inlet seam ( 78 ) being spaced from the edge or fold ( 75 ), discharge opening ( 82 a ) being between the “U” shaped inlet seam ( 78 ) and the bottom seam ( 78 ); and

wherein the step of folding includes folding the inner layer ( 71 ) in a first direction relative to the fabric of the inner layer ( 71 ) and folding the outer layer ( 73 ) in a second direction relative to the fabric of the outer layer ( 73 ) wherein the second direction of the fold ( 77 ) is different from the first direction of the fold ( 75 ) and the step of inserting has the first direction and second direction of the folds ( 75 , 77 ) being inclined relative to the other so upon assembly the inner pocket fabric layer ( 71 ) fold ( 75 ) is directionally inclined on a bias relative to the outer pocket fabric layer ( 73 ) fold ( 77 ).