Air bag inflation exit gas dispersion features

• US 6,394,491 B2
• Filed: 01/26/2001
• Issued: 05/28/2002
• Est. Priority Date: 05/08/1998
• Status: Expired due to Fees

• Current Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Original Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Inventors: Hock, Christopher, Jordan, Michael P., Soderquist, Quin
• Primary Examiner(s): CULBRETH, ERIC D
• Application Number:
  US09/770,920
• Publication Number:
  US 20010033075A1
• Time in Patent Office: 487 Days
• Field of Search: 280/736,740,741,742
• US Class Current: 280/736
• CPC Class Codes: B60R 21/217 Inflation fluid source retainers, e.g. reaction canisters; Connection of bags, covers, diffusers or inflation fluid sources therewith or together
• CPC Class Codes: B60R 21/26 characterised by the inflation fluid source or means to control inflation fluid flow arrangement or mounting thereof to the vehicle B60R21/20; blasting cartridges for producing gas under pressure in general F42B3/04; initiators or igniters therefor F42B3/10
• CPC Class Codes: B60R 21/261 with means other than bag structure to diffuse or guide inflation fluid
• CPC Class Codes: B60R 21/2644 using only solid reacting substances, e.g. pellets, powder

Abstract

An air bag device that includes an air bag cushion, a diffuser canister, and a gas generation inflator. The diffuser canister is attached to the air bag cushion and has walls configured to define an interior space therein. The walls of the diffuser canister have an interior surface, an exterior surface, and a wall thickness t. At least one of the walls has an aperture formed therethrough in communication with the interior of the air bag cushion. The gas generation inflator is configured to rapidly create a gas that exits the diffuser canister through the aperture so as to fill the air bag cushion. The aperture is defined by an edge extending between the interior and said exterior surfaces of the wall that is configured to diffuse the gas exiting the diffuser canister through the aperture. The edge of the aperture is configured such that the cross-sectional area of the aperture that is proximate to the exterior surface of the wall is larger than the cross-sectional area of the aperture proximate to the interior surface of wall. The edge includes an angled portion configured such that opposing sides of the aperture have an angle α therebetween in the range of about 20 degrees to about 145 degrees. The aperture has a diameter d₁ proximate to the interior surface of the wall and is configured so that the diameter d₁ and wall thickness t have a ratio d₁ to tin the range of about 0.5 to about 4. An alternate embodiment of the air bag device comprises an aperture defined by an edge that is configured so that the cross-section of aperture is non-smooth and causes turbulence in the gas stream.

Claims

1. An air bag device comprising:

(a) an air bag cushion having a gas inlet opening;

(b) a diffuser canister attached to said gas inlet opening of said air bag cushions, said diffuser canister having a plurality of walls configured to define an interior space therein, each of said plurality of walls having an interior surface, an exterior surface, and a wall thickness t, one of said plurality of walls having an aperture formed therethrough in communication with the interior of said air bag cushion, said aperture being defined by an edge extending between said interior surfaceand said exterior surface of said wall wherein diameter d₁ of said aperture and said wall thickness t having a ratio of diameter d₁ to wall thickness tin the range of about 0.5 to about 4.0;

(c) a gas generation inflator configured to rapidly create a gas within said diffuser canister, said gas exiting said diffuser canister through said aperture so as to fill said air bag cushion; and

(d) dispersing means for diffusing said gas exiting said diffuser canister through said aperture, said dispersing means comprising an edge defining the perimeter of said aperture, said edge being configured such that the diameter of said aperture proximate to said exterior surface of said wall is larger than the diameter d₁ of said aperture proximate to said interior surface of said wall.

2. An air bag device as recited in claim 1, wherein said ratio of diameter d₁ to wall thickness t is about 0.9 to about 2.3.

3. An air bag device comprising:

(a) an air bag cushion having a gas inlet opening;

(b) a diffuser canister, said diffuser canister having a plurality of walls configured to define an interior space therein, each of said plurality of walls having an interior surface, an exterior surface, and a wall thickness t;

(c) a gas generation inflator disposed in said interior space of said diffuser canister, said gas generation inflator being configured to rapidly create a gas within said diffuser canister, said gas exiting said diffuser canister through said aperture so as to fill said air bag cushion; and

(d) an aperture formed through one of said plurality of walls, said aperture being in communication with the interior of said air bag cushion, said aperture being defined by an edge extending between said interior surface and said exterior surface of said wall, said diameter d1 of said aperture compared to said wall thickness t having a ratio of about 0.5 to 4 and wherein said edge comprises an angled portion, said angled portion on opposing sides of said aperture having an angle α

therebetween in the range of about 20 degrees to about 145 degrees.

4. An air bag device as recited in claim 3, wherein said angle α

of said angled portions of said edge on opposing sides of said aperture having a range of about 110 degrees to about 130 degrees.

5. An air bag device comprising:

(a) an air bag cushion;

(b) a diffuser canister attached to said air bag cushion, said diffuser canister having a plurality of walls configured to define an interior space therein, each of said plurality of walls having an interior surface and an exterior surface, one of said plurality of walls having at least one aperture formed therethrough in communication with the interior of said air bag cushion;

(c) a gas generation inflator configured to rapidly create a gas within said diffuser canister, said gas existing said diffuser canister through said aperture so as to fill said air bag cushion; and

(d) an edge defining the periphery of said aperture for causing turbulence in said gas exiting said diffuser canister wherein said edge is configured such that the cross-section of said aperture is non-smooth.

6. An air bag device as recited in claim 5, wherein said non-smooth cross-section defined by said edge of said aperture is star-shaped.

7. An air bag device as recited in claim 5, wherein said edge of said aperture is configured such that the cross-sectional area said aperture increases as said gas exits said diffuser canister so as to diffuse said gas exiting said diffuser canister through said apertures in addition to causing turbulence.