Hybrid-type device for inflating vehicle safety equipment

• US 6,557,890 B1
• Filed: 07/14/2000
• Issued: 05/06/2003
• Est. Priority Date: 07/16/1999
• Status: Expired due to Fees

• Current Assignee: Autoliv AB (Autoliv Incorporated)
• Original Assignee: Autoliv AB (Autoliv Incorporated)
• Inventors: Karlin, Mats, Skanberg, Torbjörn
• Primary Examiner(s): Morris, Lesley D.
• Assistant Examiner(s): ROYAL, PAUL
• Application Number:
  US09/616,716
• Time in Patent Office: 1,026 Days
• Field of Search: 280/737, 280/741, 137/68.3, 137/68.13, 225/5, 102/530, 102/531
• US Class Current: 280/741
• CPC Class Codes: B60R 2021/2633 with a plurality of inflation levels
• CPC Class Codes: B60R 21/272 with means for increasing the pressure of the gas just before or during liberation, e.g. hybrid inflators

Abstract

The present invention relates to a hybrid-type device for inflating vehicle safety equipment with gas chamber for acceptance of compressed gases and at least two charges for the production of gas. The inflation devices is distinguished in that the two charges each have a mass of at least 5% of the mass of the compressed gas so that each charge can substantially increase the temperature of the gas and in that they are each arranged outside the gas chamber, on different sides thereof They can thus be ignited simply and precisely at predetermined without reciprocal impact.

Claims

1. Device for inflating vehicle safety equipment with a chamber (1) filled with compressed gas and at lit two pyotechnic charges structured and arranged for producing gas upon ignition, wherein

each of said charges (10, 22) has a mass of at least 5% of mass of the compressed gas in said chamber (1),

said two charges (10, 22) are situated outside said gas chamber (1) on different sides thereof,

said gas chamber (1) is essentially cylindrical and said charges (10,22) are situated on opposite ends thereof, and

on a first side end wall (3) of said gas chamber (1), on which a first (10) of said charges (10, 22) is situated, a gas chamber opening (8), connectable with the safety equipment, and a seal (19), for Initial sealing of said gas chamber opening (8), are provided.

2. Inflation device according to claim 1, wherein at least one of said charges (10,22) is structured and arranged to generate a combustible gas upon ignition, and said compressed gas stored in said gas chamber (1) is oxidizable by said combustible gas thus generated.

3. Inflation device according to claim 2, wherein said combustible gas is carbon monoxide and said oxidizable gas is oxygen.

4. Inflation device according to claim 3, wherein said compressed gas stored in said gas chamber (1) comprises approximately 10%-20% by volume of oxygen.

5. Inflation device according to claim 1, wherein said compressed gas stored in said gas chamber (1) comprises at least 80% by volume of an inert gas.

6. Inflation device according to claim 5, wherein said inert gas is argon or helium.

7. Inflation device according to claim 1, additionally comprising a discharge chamber (5) provided with a discharge opening (7) structured and arranged for connection with the safety equipment and to be brought into flow connection with said compressed gas chamber (1) and said charges (10, 22).

8. Inflation device according to claim 7, wherein said discharge chamber (5) is situated between said gas chamber (1) and one (10) of said charges (10, 22) and structured and arranged to be brought into flow connection directly therewith, and

with said other charge (22) structured and arranged to be brought into flow connection with said discharge chamber (5) through said gas chamber (1).

9. Inflation device according to claim 1, additionally comprising a control device for control of said pyrotechnic charges (10, 22) and structured and arranged to control said pyrotechnic charges (10, 22) independently of one another such that different inflation modes can be set up.

10. Inflation device according to claim 9, comprising three inflation modes (i)-(iii):

(i) in a first inflation mode, only a first one (10) of said pyrotechnic charges (10, 22) being ignited;

(ii) in a second inflation mode, only a second (22) of said pyrotechnic charges (10, 22) being ignited; and

(iii) in a third inflation mode, both said pyrotechnic charges (10, 22) being ignited.

11. Inflation device according to claim 10, wherein in said third inflation mode (iii), said charges (10, 22) are structured and arranged to be ignited in succession with a delay.

12. Inflation device according to claim 10, wherein said second (22) of said charges (10,22) is situated in a charge chamber (23) having a charge chamber opening (29) and a seal (30) provided for initial sealing of said charge chamber opening (29) prior to ignition, and upon ignition of said second charge (22), gas pressure builds up in said second charge chamber (23) and presses said seal which is a washer (30) such that said second charge chamber opening (29) is opened and gas resulting from said second charge (22) expands into said gas chamber (1) increasing gas pressure therein and subsequently opening said gas chamber opening (8).

13. Inflation device according to claim 12, wherein, upon ignition, compressed gas contained in said gas chamber (1) expands through said opening (8) into a discharge chamber (5) and flows through a second discharge opening (7) to the safety equipment.

14. Inflation device according to claim 1, additionally comprising two distinct charge chambers (9, 23) in which a respective one of each said two pyrotechnic charges (10,22) is situated,

each said charge chamber (9, 23) being provided with a respective charge chamber opening (14, 29), and respective seals (17, 30) arranged for initial sealing of said respective charge chamber opening (14, 29) prior to ignition of said respective charge (10, 22).

15. Inflation device according to claim 14, additionally comprising a cylindrical support (16) mounted in one (14) of said respective charge chamber openings (14, 29) and upon which said respective seal (17) which is a piston is mounted, such that said respective piston (17) can be impinged by gas expanding from a respective one (10) of said charges (10, 20) after ignition thereof and driven through said gas chamber opening (8).

16. Inflation device according to claim 15, wherein said piston (17) comprised a plug situated in said respective charge chamber opening (14) and sealing the same fluid-tight, and structured and arranged to be released by gas expanding in said respective charge chamber (9) and drive through said gas chamber opening (8).

17. Inflation device according to claim 15, wherein said piston is situated adjacent said gas chamber opening (8).

18. Inflation device according to claim 15, wherein said piston (17) is structured and arranged such that in an initial position prior to ignition of said respective charge (10), said piston (17) at least partially blocks said gas chamber opening (8), and said piston (17) comprises a head section (18) having a diameter (d₁₈) larger than diameter (d₁₆) of said cylindrical section (16) and smaller diameter (d₁₈) than diameter of said gas chamber opening (8).

19. Inflation device according to claim 15, additionally comprising a sealing washer (19) supported upon said piston (17) and arranged to seal said gas chamber opening (8) prior to ignition of said respective charge (10).

20. Inflation device according to claim 14, wherein said seals (17, 30) arranged for the initial sealing of said respective charge chamber openings (14, 29) are each structured and arranged to be opened by expanding gas after igniting of said respective pyrotechnic charge (10, 22).

21. Inflation device according to claim 14, wherein each of said pyrotechnic charges (10, 22) is structured and arranged to be brought into flow connection with said gas chamber (1).

22. Inflation device according to claim 1, wherein the mass of said two charges (10, 22) lies approximately in a range of 5%-20% of the mass of the compressed gas stored in said gas chamber (1).

23. Inflation device according to claim 1, wherein the mass of one of said two charges (10,22) falls approximately in the range of 5%-10% of the mass of the compressed gas stored in said gas chamber (1) and the mass of the other of said two charges (10, 22) falls approximately in the range of 10%-20% of the mass of the compressed gas stored in said gas chamber (1).

24. Inflation device according to claim 1, wherein said seal (19) for the initial sealing of the gas chamber opening (8) is structured and arranged such that said seal (19) is opened by expanding gas from at least one of said two pyrotechnic charges (10,22) after ignition of the same.

25. Inflation device according to claim 1, wherein said charges (10, 22) are structured and arranged to be different from one another in at least one of size, chemical composition, ignition speed and expansion speed.

26. Vehicle safety equipment provided with an inflation device according to claim 1.

27. Inflation device according to claim 1, wherein said pyrotechnic charges (10, 22) and chambers (9, 23) housing the same are asymmetrically arranged about said gas chamber (1).

32. Inflation device according to claim 1, being built into vehicle safety equipment which is an air bag arrangement.

28. Device for inflating vehicle safety equipment with a chamber (1) filled with compressed gas and at least two pyrotechnic charges structured and arranged for producing gas upon ignition, wherein

each of said charges (10, 22) has a mass of at least 5% of mass of the compressed gas in said chamber (1).

said two charges (10, 22) are situated outside said gas chamber (1) on different sides thereof,

said gas chamber (1) is essentially cylindrical and said charges (10,22) are situated on opposite ends thereof, and

on a first side of said gas chamber (1), on which a first (10) of said charges (10, 22) is situated, a gas chamber opening (8), connectable with the safety equipment, and a seal (19), for initial sealing of said gas chamber opening (8), are provided,

comprising charge chambers (9, 23) in which said pyrotechnic charges (10, 22) are respectively situated,

each said charge chamber (9, 23) provided with a respective charge chamber opening (14, 29) and a seal (17,30) structured and arranged for initial sealing of said charge chamber openings (14, 29) prior to ignition,

a first (9) of said charge chambers (9, 23) comprising a detonator (11) for said respective charge (10) situated on a side thereof opposite said compressed chamber (1),

a discharge chamber (5) situated between said first charge (9) and compressed gas chamber (1),

a separating wall (13) provided between said first pyrotechnic charge chamber (9) and discharge chamber (5) and through which said charge chamber opening (14) is provided,

a substantially cylindrical mount (16) situated over said charge chamber opening (14) and structured and arranged to receive said seal (17) which is a piston plug to seal said charge chamber opening (14) prior to ignition of said pyrotechnic charge (10),

a guide (20) situated in said charge chamber (5) and structured and arranged to support the separating wall (13) at a first end wall (3) separating said discharge chamber (5) and said compressed gas chamber (1) and through which said gas chamber opening (8) is situated, pierced openings being provided through said guide (20) to permit flow of gas therethrough,

said discharge chamber (5) being provided with a circumferential wall (6) connected fluid-tightly at an exterior circumference with said separating wall (13) and weaker than connection of an exterior wall (12) of said charge chamber (9) with said circumferential wall (6) on a side of said pyrotechnic charge (10) opposite said separating wall (13),

said first charge chamber (14) being formed as a cylinder,

said piston (17) in an initial position prior to ignition, being arranged to at least partially block said gas chamber opening (8), having a head section (18) with a diameter (d₁₈) larger than diameter (d₁₆) of said cylindrical mount (16) and smaller than diameter (d₈) of said gas chamber opening (8),

said second pyrotechnic charge chamber (20) being provided with a detonator (26) on an opposite side thereof from said compressed gas chamber (1), said seal (30) for said second charge chamber opening being a sealing washer, and

comprising a filler opening (27) for filling said gas chamber (1) with gas being sealed by a filler seal (28).

29. Inflation device according to claim 28, wherein said pyrotechnic charges (10, 22) and chambers (9, 23) housing the same are asymmetrically arranged about said gas chamber (1).

30. Inflation device according to claim 28, wherein, in a first inflation mode, gas pressure builds up in said first charge chamber (9), expands into said discharge chamber (5) and impinges upon said piston plug (17) which is pressed in a direction of said compressed gas chamber (1) until said cylindrical section (16) reaches a radially inwardly projecting stop (31) positioned upon said guide (20) mounted between said separating wall (13) and said first end wall (3) of said compressed gas chamber (1), resulting in said plug (17) being pressed out of said cylindrical section (16) such that said charge chamber opening (14) communicates said charge chamber (9) with said discharge chamber (5) and said gas chamber opening (8) is opened such that compressed gas can expand from said gas chamber (1) through said gas chamber opening (8) into said discharge chamber (5) and through a second discharge opening (7) provided in said discharge chamber (5) to the safety equipment.

31. Device for inflating vehicle safety equipment with a chamber (1) filled with compressed gas and at least two pyrotechnic charges structured and arranged for producing gas upon ignition, wherein

each of said charges (10, 22) has a mass of at least 5% of mass of the compressed gas in said chamber (1),

said two charges (10, 22) are situated outside said gas chamber (1) on different sides thereof,

said gas chamber (1) is essentially cylindrical and said charges (10,22) are situated on opposite ends thereof, and

on a first side of said gas chamber (1), on which a first (10) of said charges (10, 22) is situated, a gas chamber opening (8), connectable with the safety equipment, and a seal (19), for initial sealing of said gas chamber opening (8), are provided,

a control device for said pyrotechnic charges (10, 22) structured and arranged for control of said pyrotechnic charges (10, 22) and structured and arranged to control said pyrotechnic charges (10, 22) independently of one another such that different inflation modes can be set up,

comprising three Inflation modes (i)-(iii):

(i) in a first inflation mode, only a first one (10) of said pyrotechnic charges (10, 22) being ignited;

(ii) in a second inflation mode, only a second (22) of said pyrotechnic charges (10, 22) being ignited; and

(iii) in a third inflation mode, both said pyrotechnic charges (10, 22) being ignited,

comprising charge chambers (9, 23) in which said pyrotechnic charges (10, 22) are respectively situated,

each said charge chamber (9, 23) provided with a respective charge chamber opening (14, 29) and seal (17, 30) structured and arranged for initial sealing of said charge chamber openings (14, 29) prior to ignition,

a first (9) of said charge chambers (9,23) comprising a detonator (11) for said respective charge (10) situated on a side hereof opposite said compressed gas chamber (1),

a discharge chamber (5) situated between said first charge chamber (9) and compressed gas chamber (1),

a separating wall (13) provided between said first pyrotechnic charge chamber (9) and discharge chamber (5) and through which said charge chamber (14) is provided,

a substantially cylindrical mount (16) situated over said charge chamber opening (14) and structured and arranged to receive said seal (17) which is a piston plug to seal said charge chamber opening (14) prior to ignition of said pyrotechnic charge (10),

a guide (20) situated in said discharge chamber(5) and structured and arranged to support the separating wall (13) at a first end wall (3) separating said discharging chamber (5) and said compressed gas chamber (1) and through which said gas chamber opening (8) Is situated, pierced openings being provided through said guide (20) to permit flow of gas therethrough,

said discharge chamber (5) being probed with a circumferential wall (6) connected fluid-tightly at an exterior circumference with said separating wall (13) and weaker than connection of an exterior wall (12) of said charge chamber (9) with said circumferential wall (6) on a side of said pyrotechnic charge (10) opposite said separating wall (13),

said first charge chamber opening (14) being formed as a cylinder, and

said piston (17) In an initial position prior to ignition, being arranged to at least partially block said gas chamber opening (8), having a head section (18) with a diameter (d₁₈) larger than diameter (d₁₈) of said cylindrical mount (16) and smaller than diameter (d₈) of said gas chamber opening (8),

said second pyrotechnic charge chamber (23) being provided with a detonator (26) on an opposite side thereof from said compressed gas chamber (1), said seal (30) for said second charge chamber opening (29) being a sealing washer, and

comprising a filler opening (27) for filling said gas chamber (1) with gas and being sealed by a filler seal (28).