Inflator

• US 7,222,880 B2
• Filed: 02/26/2002
• Issued: 05/29/2007
• Est. Priority Date: 02/26/2001
• Status: Expired due to Term

• Current Assignee: Daicel Chemical Industries Limited (Daicel Corporation)
• Original Assignee: Daicel Chemical Industries Limited (Daicel Corporation)
• Inventors: Nakayasu, Masayuki, Iwai, Yasunori, Katsuda, Nobuyuki, Goto, Yuzo
• Primary Examiner(s): CULBRETH, ERIC D
• Application Number:
  US10/204,904
• Publication Number:
  US 20030168841A1
• Time in Patent Office: 1,918 Days
• Field of Search: 280/736, 280/737, 280/740, 280/741, 280/742
• US Class Current: 280/740
• CPC Class Codes: B60R 2021/2612 Gas guiding means, e.g. ducts
• CPC Class Codes: B60R 2021/2617 Curtain bag nozzles
• CPC Class Codes: B60R 21/261 with means other than bag structure to diffuse or guide inflation fluid
• CPC Class Codes: B60R 21/268 using instantaneous release of stored pressurised gas B60R21/26005 takes precedence
• 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

An opening portion 14 of an inflator housing 12 and a diffuser portion 20 are connected by welding, and an inflow portion 42 of a gas discharging port 40 is press-fitted in and connected to a first gas discharging hole 22 of the diffuser portion 20.

Claims

1. An inflator, comprising:

an inflator housing containing a pressurized medium and one end thereof provided with an opening portion;

a diffuser portion fixed to the opening portion of the inflator housing and provided with a gas discharging hole for discharging the pressurized medium flowing from the opening portion to an outside at a time of actuation of the inflator;

a rupturable plate closing an outflow path for the pressurized medium between the diffuser portion and the opening portion of the inflator housing;

an igniter provided in the diffuser portion for rupturing the rupturable plate;

a gas discharging port connected to the gas discharging hole of the diffuser portion for passing the pressurized medium therethrough, the gas discharging port having an inflow portion for receiving the pressurized medium discharged from the gas discharging hole, and the gas discharging port connected to the gas discharging hole by press-fitting the inflow portion into the gas discharging hole; and

fastening means for fastening a connecting portion between the gas discharging hole of the diffuser portion and the gas discharging port.

2. An air bag apparatus, comprising:

an inflator according to claim 1;

an activation signal-outputting means having an impact sensor and a control unit;

a module case accommodating the inflator; and

an air bag.

3. An inflator according to claim 1, wherein the fastening means is a metallic band wound around the connecting portion from an outside thereof.

4. An inflator, comprising:

an inflator housing containing a pressurized medium and one end thereof provided with an opening portion;

a diffuser portion fixed to the opening portion of the inflator housing and provided with a gas discharging hole for discharging the pressurized medium flowing from the opening portion to an outside at a time of actuation of the inflator;

a rupturable plate closing an outflow path for the pressurized medium between the diffuser portion and the opening portion of the inflator housing;

an igniter provided in the diffuser portion for rupturing the rupturable plate; and

a gas discharging port connected to the gas discharging hole of the diffuser portion for passing the pressurized medium therethrough, the gas discharging port having an inflow portion for receiving the pressurized medium discharged from the gas discharging hole, and the gas discharging port connected to the gas discharging hole by press-fitting the inflow portion into the gas discharging hole,

wherein a connecting portion between the gas discharging hole of the diffuser portion and the gas discharging port is fastened by a metallic band wound around the connecting portion from an outside thereof.

5. An inflator, comprising:

an inflator housing containing a pressurized medium and one end thereof provided with an opening portion;

a diffuser portion made of a single-piece element and fixed to the opening portion of the inflator housing and provided with a gas discharging hole for discharging the pressurized medium flowing from the opening portion to an outside at a time of actuation of the inflator;

a rupturable plate closing an outflow path for the pressurized medium between the diffuser portion and the opening portion of the inflator housing;

an igniter attached directly to the diffuser portion for rupturing the rupturable plate; and

a gas discharging port directly connected to the gas discharging hole of the diffuser portion by a resistance welding for passing the pressurized medium therethrough, the gas discharging port having an inflow portion for received the pressurized medium discharged from the gas discharging hole.

6. An inflator, comprising:

an inflator housing, storing pressurized medium therein, provided with an opening portion formed at one end thereof;

a diffuser portion substantially cylindrical in shape having a first end and a second end axially opposite to the first end and including a first opening provided in the first end for connecting to the opening portion such that a center axis of the diffuser portion coincides with a center axis of the inflator housing and a second opening formed in the second end provided co-axially opposite to the first opening, the diffuser portion being further provided with a reduced portion formed in an outer circumferential surface between the first end and the second end such that an outer diameter of the diffuser portion is reduced, the diffuser portion being provided with a single gas discharging hole formed in said reduced portion for discharging the pressurized medium therethrough at a time of actuation of the inflator;

a rupturable plate closing an outflow path for the pressurized medium between the diffuser portion and the opening portion of the inflator housing;

an igniter provided in the second opening of the diffuser portion for rupturing the rupturable plate; and

an L-shaped gas discharging port connected to the gas discharging hole of the diffuser portion for passing the pressurized medium therethrough, the L-shaped gas discharging port including an adapter portion connecting to the gas discharging hole and a main body portion extending in an axial direction of the inflator housing.

7. An inflator according to claim 6, further comprising:

a screen including a cylindrical member having an open end and a closed end, and having a plurality of outflow holes penetrating the cylindrical member.

8. An inflator according to claim 7, wherein the screen is arranged such that an axial direction of the screen is coincident with an axial direction of the main body portion.

9. An inflator according to claim 7, wherein the screen has a closed end and a relationship between a length L from the closed end to an outflow hole closest to the closed end and one of a diameter D of the rupturable plate and a diameter D of a portion of the rupturable plate shattered when ruptured satisfies L≧

D/2.

10. An inflator, comprising:

an inflator housing containing a pressurized medium and one end thereof provided with an opening portion;

a diffuser portion fixed to the opening portion of the inflator housing and provided with a gas discharging hole for discharging the pressurized medium flowing from the opening portion to the outside at a time of actuation of the inflator;

a rupturable plate closing an outflow path for the pressurized medium between the diffuser portion and the opening portion of the inflator housing;

an igniter provided in the diffuser portion for rupturing the rupturable plate;

a gas discharging port connected to the gas discharging hole of the diffuser portion for passing the pressurized medium therethrough; and

a screen having a plurality of outflow holes disposed in the portion port for passing the pressurized medium therethrough,

wherein the screen has a flange portion provided at a peripheral edge of an open end portion thereof, and the screen is mounted such that the flange portion makes contact with a step portion formed at an inner wall surface of the gas discharging port.

11. An inflator, comprising:

an inflator housing containing a pressurized medium and one end thereof provided with a first opening portion;

a diffuser portion made of a single-piece element and fixed to the first opening portion and provided with a gas discharging hole for discharging the pressurized medium flowing from the first opening portion to an outside at a time of actuation of the inflator;

a rupturable plate closing an outflow path for the pressurized medium between the diffuser portion and the first opening portion of the inflator housing;

an igniter attached directly to the diffuser portion for rupturing the rupturable plate; and

a gas discharging port directly connected to the gas discharging hole of the diffuser portion for passing the pressurized medium therethrough, the gas discharging port having a plurality of second opening portions formed only in a side surface thereof, at least two second opening portions being positioned symmetrically in a widthwise direction.

12. An inflator according to claim 11, further comprising:

a screen provided with a plurality of outflow holes disposed inside the gas discharging port at a position where the second opening portions are provided.

13. An inflator according to claim 12, wherein the pressurized medium is discharged from the gas discharging hole and flows out from the second opening portions of the gas discharging port via the screen upon actuation of the inflator, and an opening area (A1) of the gas discharging hole is smaller than a total opening area (A2) of holes of the screen facing the second opening portions.

14. An inflator according to claim 13, wherein A1/A2 is 0.1 to 0.95.

15. An inflator according to claim 12, wherein the screen is arranged such that an axial direction thereof is coincident with an axial direction of the gas discharging port.

16. An inflator according to claim 11, wherein the gas discharging port has a closed end and a relationship between a length L1 from the closed end to a second opening portion closest to the closed end and one of a diameter D of the rupturable plate and a diameter D of a portion of the rupturable plate shattered when ruptured satisfies L1≧

D/2.

17. An inflator, comprising:

an inflator housing containing a pressurized medium and one end thereof provided with a first opening portion;

a diffuser portion made of a single-piece element and fixed to the first opening portion and provided with a gas discharging hole for discharging the pressurized medium flowing from the first opening portion to an outside at a time of actuation of the initiator;

a rupturable plate closing an outflow path for the pressurized medium between the diffuser portion and the first opening portion of the inflator housing;

an igniter attached directly to the diffuser portion for rupturing the rupturable plate; and

a gas discharging port directly connected to the gas discharging hole of the diffuser portion for passing the pressurized medium therethrough, the gas discharging port having a plurality of second opening portions formed only in a side surface thereof, at least two second opening portions being positioned symmetrically in a widthwise direction, wherein the gas discharging port has a convex portion provided, continuously or at intervals along a longitudinal direction of the gas discharging port, on an outer surface thereof between the at least two second opening portions and a portion where the gas discharging port is connected to the diffuser portion and wherein the convex portion is provided adjacent the second opening portions.

18. An inflator, comprising:

an inflator housing containing a pressurized medium and one end thereof provided with an opening portion;

a diffuser portion fixed to the opening portion of the inflator housing and provided with a gas discharging hole for discharging the pressurized medium flowing from the opening portion to an outside at a time of actuation of the inflator;

a rupturable plate closing an outflow path for the pressurized medium between the diffuser portion and the opening portion of the inflator housing;

an igniter provided in the diffuser portion for rupturing the rupturable plate; and

a gas discharging port connected to the gas discharging hole of the diffuser portion for passing the pressurized medium therethrough, the gas discharging port having a plurality of second opening portions formed in a circumferential direction of a side surface thereof and in a first portion thereof having a first outer diameter, the gas discharging port having a connecting end attached to the gas discharging hole and a closed end opposite to the connecting end, the gas discharging port including a second portion having a larger outer diameter than the first outer diameter, and being provided between the connecting end and the first portion, the gas discharging port having a first screw portion provided on an outer surface of the second portion such that an annular clearance is provided between the first portion and a connecting member from an air bag when the connecting member is attached to the second portion.

19. An air bag apparatus, comprising:

an inflator according to claim 18; and

an air bag having, at an opening thereof, the connecting member provided with a second screw portion on an inner surface, such that the air bag is connected to the inflator by inserting the gas discharging port into the connecting member, and engaging the first screw portion with the second screw portion.

20. The air bag apparatus according to claim 19, wherein a length of the connecting member is such that the first screw portion can be screwed into the connecting member and that at least part of the second opening portions is covered with the connecting member in an axial direction of the gas discharging port.

21. An inflator, comprising:

an inflator housing charged with a pressurized medium, one end of said housing being provided with an opening portion;

a diffuser portion fixed to the opening portion of the inflator housing and provided with a gas discharging hole for discharging the pressurized medium flowing from the opening portion to the outside at a time of actuation of the inflator;

a rupturable plate closing an outflow path for the pressurized medium between the diffuser portion and the opening portion of the inflator housing;

an igniter for rupturing the rupturable plate, the igniter being attached to an opening formed in the diffuser portion such that the igniter opposes the rupturable plate; and

a gas discharging port connected to the gas discharging hole of the diffuser portion for passing the pressurized medium therethrough, the gas discharging port having a screw portion formed on an outer surface thereof.

22. An inflator according to claim 21, wherein the igniter is attached to the diffuser portion by crimping a peripheral edge of the opening.