DISCHARGE VALVE FOR AN AIR BAG

• US 3,820,814 A
• Filed: 04/03/1972
• Issued: 06/28/1974
• Est. Priority Date: 04/03/1971
• Status: Expired due to Term

• Current Assignee: Allgaier R, Brambilla L, Scholz H
• Original Assignee: Allgaier R, Brambilla L, Scholz H
• Inventors: ALLGAIER R, BRAMBILLA L, SCHOLZ H
• Application Number:
  US05/240,372
• Time in Patent Office: 816 Days
• US Class Current: 280/742
• CPC Class Codes: B60R 21/239 characterised by their venting means
• CPC Class Codes: Y10T 137/7867 Sequential

Abstract

A discharge valve for an air bag serving as passenger protective device in vehicles, especially in motor vehicles, which is automatically inflated by means of a gas when exceeding a predetermined vehicle deceleration and which is also adapted to be emptied with a certain delay by way of the discharge valve; the latter is provided in the walls of the air bag and includes a cup-shaped housing with a discharge aperture arranged within its bottom area; a cover is associated with the discharge aperture which is retained by elastic elements, such as, elastic bands at a spacing upstream of the discharge aperture in relation to the direction of the discharge flow; the cover is adapted to be displaced in the direction toward the discharge aperture as a function of the gas pressure within the air bag against the return force of the elastic elements so as to control the effective area of the discharge aperture as a function of the gas pressure prevailing on the inside of the air bag.

Claims

1. A discharge valve for a gas bag of the type serving as a passenger protective device in vehicles, which bag is automatically inflatable by means of a gas upon exceeding a predetermined vehicle deceleration and is adapted to be empited with delay by way of the discharge valve;

said discharge valve comprising;

discharge aperture means, and discharge aperture control means for controlling the free discharge cross section of said discharge aperture means such that said free discharge cross section decreases with an increasing pressure in said gas bag.

2. A discharge valve according to claim 1, wherein said air bag is fixedly connectpd to said discharge valve, and wherein said air bag is for protecting passengers in a motor vehicle.

3. A discharge valve according to claim 1, wherein said control means includes means assuring a continuously varying decrease in said free discharge cross section with a continuously increasing pressure in said gas bag, whereby varying size free discharge cross sections are provided over a range of internal gas bag pressures.

4. A discharge valve according to claim 41, wherein said discharge aperture means is arranged in the bottom of a substantially cupshaped housing of said discharge valve, and wherein said control means includes cover means and elastic retaining means for elastically retaining said cover means in position with respect to said discharge aperture means, wherein movement of said cover means with respect to said discharge aperture means effects changes in said free discharge cross section, and wherein said cover means is movable against the force of said elastic retaining means in a direction of decreasing free discharge cross section in response to increased pressure on a side of said cover means communicable directly with the pressure in said air bag.

5. A discharge valve according to claim 4, wherein said cover means is constructed such that it is movable in a direction toward said discharge aperture means to decrease said free discharge cross section while said elastic retaining means are continuously increasingly tensioned.

6. A discharge valve according to claim 5, wherein said cover means and said discharge aperture means have dimensions in a direction transverse to the direction of movement of said cover means that are smaller than the corresponding adjacent dimensions of said housing means such that said free discharge cross section is formed between peripheral edges of said cover means and walls of said housing means.

7. A discharge valve according to claim 4, characterized in that the air bag includes wall means and the discharge valve is provided in the wall means of the air bag.

8. A discharge valve according to claim 7, characterized in that the housing means protrudes from the bag in the direction of the discharge flow of the gases.

9. A discharge valve according to claim 8, characterized in that the inside of said housing means is constructed of substantially truncated, conical shape and tapers in the discharge direction of the gases.

10. A discharge valve according to claim 9, characterized in that the housing means is constituted by a bulge of the wall means of the air bag.

11. A discharge valve according to claim 9, characterized in that the housing means consists of a separately made fabric part which is connected with the wall means of the air bag.

12. A discharge valve according to claim 11, characterized in that the fabric part of the housing means is connected with the wall means of the air bag by any one of bonding, welding or sewing.

13. A discharge valve according to claim 9, characterized in that the cover means extends in the inflated and non-loaded condition of the air bag approximately in the edge plane of the cup-shaped housing means.

14. A discharge valve according to claim 9, characterized in that the cover means extends in the inflated and non-loaded condition of the air bag approximately in the wall plane thereof.

15. A discharge valve according to claim 9, characterized in that the cover means is flexible.

16. A discharge valve according to claim 15, characterized in that the cover means is constituted by a fabric part.

17. A discharge valve according to claim 10, characterized in that elastic bands are provided as retaining means.

18. A discharge valve according to claim 12, characterized in that the cover means is constituted by a fabric part.

19. A discharge valve according to claim 12, characterized in that at least three elastic bands are provided distributed substantially uniformly over the circumference of the cover means.

20. A discharge valve according to claim 14, characterized in that the elastic bands of the retaining means are disposed in their normal position substantially in a plane containing the cover means.

21. A discharge valve according to claim 14, characterized in that the cover means and the discharge aperture means are constructed of circular shape.

22. A discharge valve according to claim 16, characterized in that an annular area is provided between the cover means and the housing means adapted to be bridged by the retaining means.

23. A discharge valve according to claim 17, characterized in that the annular area between the cover means and the housing means is covered in the normal position of the retaining means by a closure ring disposed upstream of the retaining means in relation to the discharge direction of the gas.

24. A discharge valve according to claim 23, charActerized in that the closure ring is essentially immovable in its position.

25. A discharge valve according to claim 24, characterized in that the closure ring consists of essentially inelastic material.

26. A discharge valve according to claim 25, characterized in that the closure ring is connected with the wall means of the air bag.

27. A discharge valve according to claim 26, characterized in that a gas outlet opening is provided in the air bag means in addition to the discharge valve.

28. A discharge valve according to claim 7, characterized in that the housing means is constituted by a bulge of the wall means of the air bag.

29. A discharge valve according to claim 42, characterized in that the housing means is constructed of substantially truncated, conical shape and tapers in the discharge direction of the gases.

30. A discharge valve according to claim 7, characterized in that the housing means consists of a separately made fabric part which is connected with the wall means of the air bag.

31. A discharge valve according to claim 30, characterized in that the fabric part of the housing means is connected with the wall means of the air bag by any one of bonding, welding or sewing.

32. A discharge valve according to claim 4, characterized in that the cover means extends in the inflated and non-loaded condition of the air bag approximately in the edge plane of the cup-shaped housing means.

33. A discharge valve according to claim 4, characterized in that the cover means extends in the inflated and non-loaded condition of the air bag approximately in the wall plane thereof.

34. A discharge valve according to claim 4, characterized in that the cover means is flexible.

35. A discharge valve according to claim 34, characterized in that the cover means is constituted by a fabric part.

36. A discharge valve according to claim 4, characterized in that elastic bands are provided as retaining means.

37. A discharge valve according to claim 36, characterized in that at least three elastic bands are provided distributed substantially uniformly over the circumference of the cover means.

38. A discharge valve according to claim 36, characterized in that the elastic bands of the retaining means are disposed in their normal position substantially in a plane containing the cover means.

39. A discharge valve according to claim 4, characterized in that the cover means and the discharge aperture means are constructed of circular shape.

40. A discharge valve according to claim 4, characterized in that an annular area is provided between the cover means and the housing means adapted to be bridged by the retaining means.

41. A discharge valve according to claim 40, characterized in that the annular area between the cover means and the housing means is covered in the normal position of the retaining means by a closure ring disposed upstream of the retaining means in relation to the discharge direction of the gas.

42. A discharge valve according to claim 41, characterized in that the closure ring is essentially immovable in its position.

43. A discharge valve according to claim 41, characterized in that the closure ring consists of essentially inelastic material.

44. A discharge valve according to claim 41, characterized in that the closure ring is connected with wall means of the air bag.

45. A discharge valve according to claim 4, characterized in that a gas outlet opening is provided in the air bag means in addition to the discharge valve.