Hybrid inflator with bore and burst disk

• US 5,918,900 A
• Filed: 11/20/1996
• Issued: 07/06/1999
• Est. Priority Date: 11/20/1996
• Status: Expired due to Fees

• Current Assignee: Key Safety Systems, Inc. (Ningbo Junsheng Investment Group Co., Ltd.)
• Original Assignee: Breed Automotive Technology, Inc. (Ningbo Junsheng Investment Group Co., Ltd.)
• Inventors: Ennis, Thomas A.
• Primary Examiner(s): Nelson, Peter A.
• Application Number:
  US08/752,098
• Time in Patent Office: 958 Days
• Field of Search: 280/736, 280/737, 280/740, 280/742, 102/289
• US Class Current: 280/736
• 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 cylindrically shaped hybrid inflator comprising: a pressure vessel filled with pressurized inflation gas, comprising a center body (22) having a first (24a) and a second (24b) end, a first exit orifice (29) located between the first and second end, a frangible disk (32) closing the orifice (29) and a pyrotechnic element for causing the disk to rupture and permit inflation gas to exit the orifice; a first cylindrical portion (50) sealingly attached to the first end and a second cylindrical portion sealing attached to the second end.

Claims

1. A hybrid inflator (20) comprising:

a pressure vessel (100) filled with pressurized inflation gas, comprising

a center body (22) having a first (24a) and a second (24b) end, an exit orifice (29) located between the first and second end, a first frangible disk (32) closing the orifice (29) and first means (80) for causing the disk to rupture and permit inflation gas to exit the orifice;

a first cylindrical portion (50) sealingly attached to the first end and a second cylindrical portion (50) sealing attached to the second end;

wherein the body (22) includes a generant bore (60) generally below the exit orifice and wherein the inflator includes a generant housing (86) within the generant bore (60), and quantity of propellant (84) which when activated causes the first frangible disk to open permitting inflation gas to exit the inflator into an air bag (102).

2. The device as defined in claim 1 wherein the center body (30) includes fill means (34,36) for introducing an inert gas at a predetermined pressure level into the inflator.

3. The device as defined in claim 1 wherein the exit orifice (29) is located midway between the ends of the first and second ends.

4. The device as defined in claim 1 wherein the center body includes a through passage (25) including a converging nozzle (94a,b) between each end and the exit orifice, each converging nozzle including a throat portion (96a,b) below the exit orifice.

5. The device as defined in claim 4 further including gas flow diverting means (160) for diverting a generally unidirectional gas flow exiting the exit orifice into a multi-directional gas flow.

6. The device as defined in claim 5 wherein the multi-directional gas flow is generally perpendicular to the gas flow exiting the exit orifice.

7. The device as defined in claim 1 further including gas flow diverting means (160) for diverting the generally unidirectional gas flow exiting the exit orifice into a multi-directional gas flow.

8. The device as defined in claim 7 wherein the multi-directional gas flow is generally perpendicular to the gas flow exiting the exit orifice.

9. The device as defined in claim 1 including a slidable piston with a central passage of the generant housing.

10. The device as defined in claim 1 wherein the generant housing (86) includes an arcuately shaped external wall (85) forming a part of each nozzle throat portion.

11. The device as defined in claim 1 wherein a sliding piston 110 is located in the central passage (90) within the generant housing and movable into the first burst disk (92) upon activation of the propellant.

12. The device as defined in claim 11 wherein an end of the central passage (90) is sealed by a second burst disk.

13. The device as defined in claim 1 wherein the body, proximate each end (24a,b) includes a groove or slot and wherein an edge of each respective cylindrical member (50) is secured therein.