Multi-stage expansion tire hybrid inflator

• US 6,793,244 B1
• Filed: 11/07/2001
• Issued: 09/21/2004
• Est. Priority Date: 06/18/1999
• Status: Expired due to Term

• Current Assignee: Daicel Chemical Industries Limited (Daicel Corporation)
• Original Assignee: Daicel Chemical Industries Limited (Daicel Corporation)
• Inventors: Yamazaki, Masayuki, Katsuda, Nobuyuki, Nakashima, Yoshihiro
• Primary Examiner(s): Ilan, Ruth
• Application Number:
  US09/959,766
• Time in Patent Office: 1,049 Days
• Field of Search: 280/737, 280/741, 280/742, 280/736, 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

A hybrid inflator having improved inflating performance of an air bag is provided. A gas generator provided in a housing 102, in which a pressurized medium is charged under a high pressure, includes a first gas generating chamber 120 and a second gas generating chamber 130. By allowing the two gas generating chambers to generate high-temperature combustion gas, respectively, the inflating speed and the like of the air bag are further improved.

Claims

1. A multistage-inflating hybrid inflator for a safety system of a vehicle provided with an air bag, comprising:

an inflator housing, an interior thereof being filled with a pressurized medium containing inert gas;

an ignition means chamber connected to a gas generator; and

said gas generator provided in said inflator housing and having a first gas generating chamber and a second gas generating chamber for storing gas generating means, and a single common transferring tube penetrating through the first gas generating chamber and the second gas generating chamber, the transferring tube providing heat to ignite the gas generating means provided inside the first gas generating chamber.

5. A multistage-inflating hybrid inflator as claimed in any one of claims 1 and 2 to 4, wherein said first gas generating chamber communicates with said inflator housing and said second gas generating chamber also communicates with said inflator housing.

8. A multistage-inflating hybrid inflator as claimed in any one of claims 1 and 2 to 4, wherein flowpaths which directs gases generated in said first and second gas generating chambers to said inflator housing are independent of each other.

9. The multistage-inflating hybrid inflator as claimed in claim 8, wherein a gas generated in the first gas generating chamber flows independently in one direction within the inflator housing and a passage through which gas generated in the second gas generating chamber flows is located in an opposite direction with respect to a direction to which the gas generated in the first gas generating chamber flows.

10. A multistage-inflating hybrid inflator as claimed in any one of claims 1 and 2 to 4, wherein said ignition means chamber has a first ignition chamber and a second ignition chamber, each of the first ignition chamber and the second ignition chamber including ignition means, said first ignition chamber and said first gas generating chamber communicating with each other through a first communication hole which is closed with a first closing means before said first ignition means is activated, said second ignition chamber and said second gas generating chamber communicating with each other through a second communication hole which is closed with a second closing means before said second ignition means is activated.

11. The multistage-inflating hybrid inflator as claimed in claim 10, wherein the first ignition chamber and the second ignition chamber are aligned in parallel to each other in the lateral direction of the housing and adjacent to each other.

12. An air bag system provided with an activation signal-outputting means, comprising:

an impact sensor;

a control unit; and

a module case in which the multistage-inflating hybrid inflator as claimed in any one of claims 1 and 2 to 4 and an air bag are accommodated, wherein an inflating speed of said air bag is adjustably set.

30. A multistage-inflating hybrid inflator as claimed in claim 1, wherein said transferring tube has a hole for communicating the first gas generating chamber and an interior of the transferring tube.

2. A multistage-inflating hybrid inflator for a safety system of a vehicle provided with an air bag, comprising:

an inflator housing, an interior thereof being filled with a pressurized medium containing inert gas, the inflator further having principal closing means to close, before actuation, transition of the pressurized medium outward to discharging ports and a projectile for rupturing the principal closing means on actuation;

a gas generator accommodated in the inflator housing and having a first gas generating chamber and a second gas generating chamber, each containing gas generating means therein;

an ignition means chamber connected to the gas generator; and

a transfer charge provided independently from the gas generating means, said transfer charge being ignited by said ignition means to drive the projectile to rupture the principal closing means.

3. A multistage-inflating hybrid inflator as claimed in claim 2, wherein a tip of the projectile is disposed in a space where the pressurized medium is charged.

4. A multistage-inflating hybrid inflator as claimed in claim 2, wherein a tip of the projectile is disposed in a space defined by an element other than said inflator housing.

6. A multistage-inflating hybrid inflator as claimed in any one of claims 2 to 4, wherein said first and second gas generating chambers are arranged in series and adjacently to each other in a longitudinal direction of said inflator housing.

7. The multistage-inflating hybrid inflator as claimed in any one of claims 2 to 4, wherein the first and second gas generating chambers are aligned in parallel to each other in a lateral direction of the housing and are adjacent to or separated from each other.

13. A multistage-inflating hybrid inflator for a safety system of a vehicle provided with an air bag, comprising:

an inflator housing, an interior thereof being filled with a pressurized medium containing inert gas;

a gas generator provided in said inflator housing and having at least one gas generating chamber for storing gas generating means; and

a retainer disposed inside the gas generator, said retainer including a larger-diameter cylinder having one end closed and another end open, and a smaller-diameter cylinder having both ends open, the smaller-diameter cylinder being integrated with the larger-diameter cylinder to project toward the inside as well as the open end of the larger-diameter cylinder.

14. A multistage-inflating hybrid inflator as claimed in claim 13, wherein a side-wall length of the larger diameter cylinder and a side-wall length of the smaller-diameter cylinder are the same as or different from each other.

15. A multistage-inflating hybrid inflator as claimed in claim 13, wherein a side-wall length of the larger-diameter cylinder is longer or shorter than a side-wall length of the smaller-diameter cylinder.

16. A multistage-inflating hybrid inflator as claimed in claim 13, further comprising:

a charge transferring chamber surrounded by said at least one gas generating chamber,

wherein, the retainer is fitted into the charge-transferring chamber at the open end of the smaller-diameter cylinder, an outer side wall of the larger-diameter cylinder is in contact with an inner wall of the gas generating chamber, an inner wall of the smaller-diameter cylinder is in contact with an outer side wall of the charge-transferring chamber, and the at least one gas generating chamber is divided into at least two sections by the closed end in the longitudinal direction.

18. A multistage-inflating hybrid inflator as claimed in claim 16, wherein at least two retainers are disposed such that the open end of each of retainer may be arranged in the same direction.

17. A gas generator having at least one gas generating chamber around a charge-transferring chamber, comprising:

an inflator housing, an interior thereof being filled with a pressurized medium containing inert gas;

a gas generator provided in said inflator housing and having at least one gas generating chamber for storing gas generating means; and

a retainer disposed inside the gas generator, said retainer including a larger-diameter cylinder having one end closed and another end open, and a smaller-diameter cylinder having both ends open, the smaller-diameter cylinder being integrated with the larger-diameter cylinder to project toward the inside as well as the open end of the larger-diameter cylinder, the retainer being disposed in order to one of retain a gas generating agent and adjust an amount of the gas generating agents, the retainer being fitted into the charge-transferring chamber at an open end of the smaller-diameter cylinder, an outer side wall of the larger-diameter cylinder being in contact with an inner wall of the gas generating chamber, and the volume of the gas generating chamber being controlled by the closed end.

19. A multistage-inflating hybrid inflator for a safety system of a vehicle provided with an air bag, comprising:

an inflator housing having an interior thereof filled with a pressure medium containing an inert gas;

a gas generator provided in said inflator housing and having a first gas generating chamber and a second gas generating chamber, each including gas generating means therein, and a single common charge transferring tube penetrating through the first gas generating chamber and the second gas generating chamber, the transferring tube providing heat to ignite the gas generating means provided inside the first gas generating chamber; and

an ignition means chamber provided with ignition means connected to said gas generator, said ignition means including two initiators attached to one initiator collar and provided in said ignition means chamber such that at least one of two initiators is eccentrically placed with respect to at least one of the first gas generating chamber and the second combustion chamber.

20. A multistage-inflating hybrid inflator as claimed in claim 19, wherein the two initiators are attached to said one initiator collar by resin.

21. The multistage-inflating hybrid inflator as claimed in claim 19 or 20, wherein the first gas generating chamber and the second gas generating chamber are aligned in series in the longitudinal direction of the housing and adjacent to each other.

22. The multistage-inflating hybrid inflator as claimed in any of claims 19 to 20, wherein the ignition means chamber includes a first ignition chamber and a second ignition chamber, each of the first ignition chamber and the second ignition chamber including ignition means, the first ignition chamber communicating with the first gas generating chamber through a first communicating hole, the first communicating hole being closed by first closing means prior to activation of the first ignition means, the second igniting chamber communicating with the second gas generating chamber through a second communicating hole, the second communicating hole being closed by second closing means prior to activation of the ignition means.

23. An air bag system comprising:

actuation signal-outputting means including an impact sensor and a control unit; and

a module case containing therein the hybrid inflator as defined in any of claims 19 to 20.

31. A multistage-inflating hybrid inflator as claimed in claim 19, wherein said transferring tube has a hole for communicating the first gas generating chamber and an interior of the transferring tube.

24. A multistage-inflating hybrid inflator for a safety system of a vehicle provided with an air bag, comprising:

an inflator housing, an interior thereof being filled with a pressurized medium containing inert gas, the inflator further having principal closing means to close, before actuation, transition of the pressurized medium outward to discharging ports and a projectile to rupture the principal closing means on actuation;

a gas generator accommodated in the inflator housing and having at least one gas generating chamber, each containing gas generating means therein; and

a retainer disposed inside the gas generator, said retainer including a larger-diameter cylinder having one end closed and another end open, and a smaller-diameter cylinder having both ends open, the smaller-diameter cylinder being integrated with the larger-diameter cylinder to project toward the inside as well as the open end of the larger-diameter cylinder.

25. A multistage-inflating hybrid inflator as claimed in claim 24, wherein a side-wall length of the larger diameter cylinder and a side-wall length of the smaller-diameter cylinder are the same as or different from each other.

26. A multistage-inflating hybrid inflator as claimed in claim 24, wherein a side-wall length of the larger-diameter cylinder is longer or shorter than a side-wall length of the smaller-diameter cylinder.

27. A multistage-inflating hybrid inflator as claimed in claim 24, wherein a tip of the projectile is disposed in a space defined by an element other than said inflator housing.

28. A multistage-inflating hybrid inflator as claimed in claim 24, further comprising:

a charge transferring chamber surrounded by said at least one gas generating chamber,

wherein, the retainer is fitted into the charge-transferring chamber at the open end of the smaller-diameter cylinder, an outer side wall of the larger-diameter cylinder is in contact with an inner wall of the gas generating chamber, an inner wall of the smaller-diameter cylinder is in contact with an outer side wall of the charge-transferring chamber, and the at least one gas generating chamber is divided into at least two sections by the closed end in the longitudinal direction.

29. A multistage-inflating hybrid inflator as claimed in claim 28, wherein at least two retainers are disposed such that the open end of each of retainer may be arranged in the same direction.