Airbag for vehicle occupant restraint system

1. An airbag for a vehicle occupant restraint system, comprising:

an airbag panel ( 16 ) defining an inflatable airbag volume and including a front panel portion ( 18 ) and a rear panel portion ( 20 ),

a tether ( 22 ) extending in the interior of the airbag ( 14 ) across the inflatable airbag volume,

a discharge orifice ( 24 ) formed in the rear panel portion ( 20 ) of the airbag panel ( 16 ), as well as

a first closing tab ( 26 ) and a second closing tab ( 28 ) for closing the discharge orifice ( 24 ),

wherein the tether ( 22 ) extends from a first tether end ( 32 ) tightly connected to the front panel portion ( 18 ) in the direction of the discharge orifice ( 24 ) to an opposed second tether end ( 34 ),

wherein the first closing tab ( 26 ) extends from a first tab end ( 36 ) tightly connected to the rear panel portion ( 20 ) to a second tab end ( 38 ) tightly connected to the second tether end ( 34 ), and

wherein the second closing tab ( 28 ) is fastened adjacent to the discharge orifice ( 24 ) on the rear panel portion ( 20 ),

wherein the two closing tabs ( 26 , 28 ) are coupled by a connection that couples the closing tabs ( 26 , 28 ) together in a fluid-tight manner to close the discharge orifice prior to inflation of the airbag and which is configured to be released in response to a vehicle occupant ( 30 ) impacting on the inflated airbag ( 10 ) in order to open the discharge orifice and vent inflation fluid from the airbag volume.

2. The airbag according to claim 1 , wherein the releasable connection between the two closing tabs ( 26 , 28 ) is in the form of a tear seam ( 42 ).

3. The airbag according to claim 2 , wherein the tear seam ( 42 ) includes two linear seam portions ( 46 , 48 ) which extend away from each other at an angle (α) in arrow shape starting from a joint seam tip ( 50 ) to a respective free seam portion end.

4. The airbag according to claim 3 , wherein when the airbag ( 10 ) is completely inflated, the two closing tabs ( 26 , 28 ) extend in the interior of the airbag ( 14 ) transversely to the airbag panel ( 16 ) and outside the airbag ( 10 ) in parallel to the airbag panel ( 16 ) so that in the area of the discharge orifice ( 24 ) a fold ( 52 ) is formed, wherein the tear seam ( 42 ) is configured in a closing tab portion extending transversely to the airbag panel ( 16 ).

5. The airbag according to claim 4 , wherein the seam tip ( 50 ) abuts on the fold ( 52 ) and the linear seam portions ( 46 , 48 ) extend starting from the seam tip ( 50 ) in the direction of the front panel portion ( 18 ).

6. The airbag according to claim 1 , wherein the closing tabs ( 26 , 28 ) extend from the interior of the airbag ( 10 ) through the discharge orifice ( 24 ) to the outside of the airbag ( 10 ), the second closing tab ( 28 ) including a first tab end ( 40 ) with the first tab ends ( 36 , 40 ) of the two closing tabs ( 26 , 28 ) being fastened from outside on the rear panel portion ( 20 ) of the airbag panel ( 16 ).

7. The airbag according claim 1 , wherein the tether ( 22 ) and the first closing tab ( 26 ) are integrally formed.

8. A steering wheel assembly comprising a vehicle steering wheel ( 12 ) which is rotatable about a steering axis (A) and comprising an airbag module which includes an airbag ( 14 ) according to claim 1 .

9. An airbag for a vehicle occupant restraint system, comprising:

an airbag panel ( 16 ) defining an inflatable airbag volume and including a front panel portion ( 18 ) and a rear panel portion ( 20 ),

a tether ( 22 ) extending in the interior of the airbag ( 14 ) across the inflatable airbag volume,

a discharge orifice ( 24 ) formed in the rear panel portion ( 20 ) of the airbag panel ( 16 ), as well as

a first closing tab ( 26 ) and a second closing tab ( 28 ) for closing the discharge orifice ( 24 ) and extending from the interior of the airbag ( 10 ) in the direction of the discharge orifice ( 24 ),

wherein the tether ( 22 ) extends from a first tether end ( 32 ) tightly connected to the front panel portion ( 18 ) in the direction of the discharge orifice ( 24 ) to an opposed second tether end ( 34 ),

wherein the first closing tab ( 26 ) extends from a first tab end ( 36 ) tightly connected to the rear panel portion ( 20 ) to a second tab end ( 38 ) tightly connected to the second tether end ( 34 ), and

wherein the second closing tab ( 28 ) includes a first tab end ( 40 ) with the first tab ends ( 36 , 40 ) of the two closing tabs ( 26 , 28 ) being fastened on opposite sides of the discharge orifice ( 24 ) from inside on the rear panel portion ( 20 ) of the airbag panel ( 16 ) so that, when the airbag ( 10 ) is completely inflated, the two closing tabs ( 26 , 28 ) extend toward each other starting from the first tab ends ( 36 , 40 ) substantially in parallel to the airbag panel ( 16 ), contact each other in the area of the discharge orifice ( 24 ) and then extend transversely to the airbag panel ( 16 ) while forming a fold ( 52 ), wherein the tear seam ( 42 ) abuts on the fold ( 52 ) and is formed in a closing tab portion which extends transversely to the airbag panel ( 16 ),

wherein the two closing tabs ( 26 , 28 ) are coupled by a connection configured to be released in response to a vehicle occupant ( 30 ) impacting on the inflated airbag ( 10 ) in order to open the discharge orifice and vent inflation fluid from the airbag volume.

10. The airbag according to claim 9 , wherein the tear seam ( 42 ) includes two linear seam portions ( 46 , 48 ) which extend in arrow shape away from each other at an angle (α) starting from a joint seam tip ( 50 ) to a respective free seam portion end, wherein the seam tip ( 50 ) abuts on the fold ( 52 ) and the linear seam portions ( 46 , 48 ) extend starting from the seam tip ( 50 ) toward the front panel portion ( 18 ).