AIRBAG INFLATOR

• US 20110254255A1
• Filed: 10/30/2009
• Published: 10/20/2011
• Est. Priority Date: 10/30/2008
• Status: Active Grant

• Current Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Original Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Inventors: Chen, Jianlin, Tasaki, Yoji, Sakamoto, Akinori, Nash, Krista, Jenkins, Casey
• Granted Patent: US 8,328,234 B2
• Time in Patent Office: Days
• US Class Current: 280/741
• CPC Class Codes: B60R 2021/26011 using a filter through which the inflation gas passes
• CPC Class Codes: B60R 21/2644 using only solid reacting substances, e.g. pellets, powder

Abstract

To ensure that a wire wound filter can be incorporated into a base of a pressure vessel easily, the present invention provides an airbag inflator in which a pressure vessel 2 constituted by a base 2b and a diffuser 2a accommodates an igniter 3, a gas generating agent 4, a filter 21, and an inner cover 24 that covers the gas generating agent 4 and includes a bent portion 24a that contacts an inner wall of the filter 21. The filter 21 has a layered structure constituted by an inner filter 22 wound into a cylindrical shape, in which upper and lower end surfaces are formed in a tapered shape that decreases in height toward an outer peripheral side, and a wire mesh outer filter 23 that is fitted over an outer peripheral surface of the inner filter 22, excluding at least respective end portions formed in the tapered shape, and has a slightly larger outer diameter than an inner diameter of the base 2b. The filter 21 is press-fitted into the base 2b. Thus, the filter can be incorporated into the base easily. Further, close contact with the inner cover can be maintained when the diffuser and the base are integrated by welding.

Claims

1. An airbag inflator in which a pressure vessel formed by integrally welding a diffuser to abase accommodates an igniter and a gas generating agent, a filter disposed along an inner peripheral wall of said pressure vessel, and an inner cover that covers said gas generating agent and includes a bent portion that contacts an inner wall of said filter,

the airbag inflator being characterized in that

said filter has a layered structure constituted by an inner filter in which upper and lower end surfaces of a wire wound filter, wound into a cylindrical shape, are formed in a tapered shape that decreases in height toward an outer peripheral side, and a wire mesh outer filter that is fitted over an outer peripheral surface of said inner filter, excluding at least respective end portions formed in said tapered shape, and has a slightly larger outer diameter than an inner diameter of said base, and

said filter is press-fitted into said base.

2. The airbag inflator according to claim 1, characterized in that said tapered shape on a lower end side of said filter contacts an inner wall of said base in alignment with a shape thereof when said filter is press-fitted into said base.

3. The airbag inflator according to claim 1 or 2, characterized in that a height of said inner filter is set such that an outer peripheral end of said inner filter does not contact an inner wall of said diffuser integrated with said base.

4. The airbag inflator according to any of claims 1 to 3, characterized in that said bent portion of said inner cover is formed to be long enough to remain in contact with an inner wall of said inner filter following activation of said inflator.

5. The airbag inflator according to any of claims 1 to 4, characterized in that said inner filter is formed from a columnar filter constituted by expanded metal having various mesh openings, in place of said wire wound filter wound into said cylindrical shape.