Gas bag for a car passenger-protecting system

1. A passenger protecting system, comprising:

a gas generator; and

a gas bag including an envelope portion and a filling channel with a narrow portion which extends along a predefined deployment direction, wherein the narrow portion has a length greater than a width, wherein the system is configured so that inflation gas from the gas generator directly enters the filling channel;

wherein at least part of the envelope portion is inserted into the narrow portion of the filling channel;

wherein the part of the envelope portion that is inserted into the narrow portion of the filling channel is folded into an envelope pack, wherein the envelope pack is formed so that a long axis of the envelope pack is arranged perpendicularly to a width of the gas bag;

wherein the envelope pack is folded together in a middle of the long axis of the envelope pack to form a U-shaped pack that is inserted into the narrow portion of the filling channel.

2. The system as claimed in claim 1 , wherein the filling channel is connected to the gas generator.

3. The system as claimed in claim 1 , wherein one end of the filling channel is adapted to be connected to the gas generator and the part of the envelope portion that is inserted into the narrow portion is located immediately in front of a connection point of the gas generator.

4. The system as claimed in claim 3 , wherein the filling channel forms a side pocket which is located laterally beside the connection point of the gas generator.

5. The system as claimed in claim 1 , wherein the part of the envelope portion that is inserted into the narrow portion is at least partly zigzag-folded, pleated and/or rolled together.

6. The system as claimed in claim 5 , wherein the part of the envelope portion that is inserted into the narrow portion is zigzag-folded, pleated and/or rolled together at an end of the envelope facing away from the filling channel to form a zigzag-folded, pleated and/or rolled together envelope pack, wherein the envelope pack is folded together at least once to form the U-shaped pack.

7. The system as claimed in claim 1 , wherein the gas bag has two or more gas bag chambers.

8. The system as claimed in claim 7 , wherein the gas bag has at least one inner gas bag chamber that is surrounded by an outer gas bag chamber.

9. The system as claimed in claim 1 , wherein the filling channel is formed laterally, at least partly, by a seam in the envelope of the gasbag.

10. The system as claimed in claim 7 , wherein the filling channel is formed, at least partly, by side walls of associated gas bag chambers.

11. The system as claimed in claim 1 , wherein the filling channel is formed, at least partly, by a diffuser layer fitted in the gas bag and/or by retaining straps.

12. The system as claimed in claim 1 , wherein the filling channel is at least partly tubular.

13. The system as claimed in claim 12 , wherein a cross section of the filling channel widens like a funnel at an open end of the filling channel.

14. The system as claimed in claim 1 , wherein the gas bag is a pelvis-thorax gas bag that includes a pelvis region and a thorax region.

15. The system as claimed in claim 14 , wherein the pelvis region of the gas bag is inserted into the filling channel.

16. The system as claimed in claim 14 , wherein the gas bag is accommodated in a backrest of a motor vehicle seat so that the predefined deployment direction extends parallel to the backrest of the motor vehicle seat, in a direction of the vehicle seat area.

17. The system as claimed in claim 1 , wherein the gas bag is a head-thorax gas bag that includes a head region and a thorax region.

18. The system as claimed in claim 17 , wherein the head region of the gas bag is inserted into the filling channel.

19. The system as claimed in claim 17 , wherein the gas bag is accommodated in a backrest of a motor vehicle seat so that the predefined deployment direction extends parallel to the backrest of the motor vehicle seat, in a direction of the vehicle roof.

20. The system as claimed in claim 1 , wherein the gas bag is a head-thorax-pelvis gas bag that includes a head region, a thorax region, and a pelvis region.

21. The system as claimed in claim 20 , wherein the head region and/or the pelvis region of the gas bag is in each case inserted into the filling channel.

22. The system as claimed in claim 21 , wherein the gas bag is fitted in a backrest of a motor vehicle seat so that the predefined deployment direction of the filling channel for the head region extends parallel to the backrest of the motor vehicle seat, in a direction of the vehicle roof, and/or the predefined deployment direction of the filling channel for the pelvis region extends parallel to the backrest of the motor vehicle seat, in a direction of the vehicle seat area.

23. A method for folding a gas bag, comprising:

inserting at least a part of a gas bag envelope of the gas bag into an envelope section of the gas bag envelope; and

inserting the part of the gas bag envelope into a narrow portion of a filling channel, wherein the narrow portion has a length greater than a width;

wherein the filling channel is party formed by the gas bag envelope;

wherein the filling channel extends along a predefined deployment direction;

wherein the part of the gas bag envelope that is inserted into the narrow portion of the filling channel is folded together into an envelope pack, wherein the envelope pack is formed so that a long axis of the envelope pack is arranged perpendicularly to a width of the bas bag;

wherein the envelope pack is folded in a middle of the long axis of the envelope pack to form a U-shaped pack that is inserted into the narrow portion of the filling channel.

24. The method as claimed in claim 23 , wherein the part of the gas bag envelope that is inserted into the narrow portion is at least partly zigzag-folded, pleated and/or rolled together.

25. The method as claimed in claim 24 , wherein the part that is inserted is firstly zigzag-folded, pleated and/or rolled together at an end of the envelope facing away from the filling channel to form a zigzag-folded, pleated and/or rolled together envelope pack, wherein the envelope pack is folded together at least once to form the U-shaped pack.

26. A system for protecting passengers of a vehicle, comprising:

a gas generator; and

an air bag, including a folded section and a filling channel with a narrow portion, wherein the narrow portion has a length greater than a width;

wherein the filling channel is adjacent to the gas generator;

wherein the folded section is inserted in the narrow portion of the filling channel so that when inflation gas from the gas generator enter the filling channel, gas pressure builds up, expelling the folded section in a predetermined direction;

wherein the folded section that is inserted into the narrow portion of the filling channel is formed by a part of the air bag that is folded into an envelope pack, wherein the envelope pack is formed so that a long axis of the envelope pack is arranged perpendicularly to a width of the air bag;

wherein the envelope pack is folded together in a middle of the long axis of the envelope pack to form a U-shaped pack that is inserted into the narrow portion of the filling channel.

27. The system as claimed in claim 1 , wherein the part of the envelope portion that forms the envelope pack is rolled to form the envelope pack.

28. The method as claimed in claim 23 , wherein the part of the gas bag envelope that forms the envelope pack is rolled to form the envelope pack.

29. The system as claimed in claim 26 , wherein the part of the air bag that forms the envelope pack is rolled to form the envelope pack.

30. The method as claimed in claim 23 , wherein the envelope pack is folded before the envelope pack is inserted into the narrow portion of the filling channel.