Inflator with vent

• US 20080203707A1
• Filed: 02/26/2007
• Published: 08/28/2008
• Est. Priority Date: 02/26/2007
• Status: Active Grant

• Current Assignee: TRW Airbag Systems GmbH (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: TRW Airbag Systems GmbH (Zeppelin - Stiftung der Stadt Friedrichshafen), TRW Vehicle Safety Systems Incorporated (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Fischer, Kurt F., Last, Detlef, Englbrecht, Karl
• Granted Patent: US 7,735,860 B2
• Time in Patent Office: Days
• US Class Current: 280/728.2
• CPC Class Codes: B60R 2021/23382 Internal tether means
• CPC Class Codes: B60R 21/2338 Tethers
• CPC Class Codes: B60R 21/276 with means to vent the inflation fluid source, e.g. in case of overpressure B60R21/30 takes precedence; venting means on inflatable member walls B60R21/239

Abstract

An apparatus (10) includes an inflatable vehicle occupant protection device (14) and an inflator (16) for providing inflation fluid for inflating the protection device. The inflator (16) includes an inflation fluid control structure (100). The control structure (100) includes discharge openings (116) for directing inflation fluid into an inflatable volume (72) of the protection device (14) and vent openings (118) for venting inflation fluid outside the inflatable volume. The control structure (100) also includes a vent member (132) actuatable from an open condition permitting inflation flow through the vent openings (118) to a closed condition blocking inflation fluid flow through the vent openings.

Claims

1. An apparatus comprising:

an inflatable vehicle occupant protection device; and

an inflator for providing inflation fluid for inflating the protection device, the inflator comprising an inflation fluid control structure, the control structure comprising;

discharge openings for directing inflation fluid into an inflatable volume of the protection device;

vent openings for venting inflation fluid outside the inflatable volume; and

a vent member actuatable from an open condition permitting inflation flow through the vent openings to a closed condition blocking inflation fluid flow through the vent openings.

2. The apparatus recited in claim 1, wherein the vent member is actuatable in response to a position of the occupant when the protection device is inflated and deployed.

3. The apparatus recited in claim 2, wherein the vent member is actuatable to the closed condition in response to an occupant in a normally seated position, the vent member being maintained in the open condition in response to an occupant positioned away from the normally seated position.

4. The apparatus recited in claim 1, wherein the vent member is actuatable in response to deployment of the protection device.

5. The apparatus recited in claim 1, further comprising a tether that connects the vent member to the protection device, the vent member being actuatable in response to tension on the tether, tension on the tether being applied when the protection device reaches a predetermined deployment position.

6. The apparatus recited in claim 1, wherein the control structure comprises a housing defining the discharge openings and the vent openings, the housing comprising a passage providing fluid communication between the discharge openings and the vent openings, the vent member blocking the passage in the closed condition.

7. The apparatus recited in claim 6, wherein the vent member is supported for sliding movement in the housing, the apparatus further comprising a tether connecting the vent member to the protection device, the vent member pulling the vent member and causing the vent member to slide from the open condition to the closed condition when the protection device reaches a predetermined deployment position.

8. The apparatus recited in claim 6, wherein the control structure comprises an assist structure, the assist structure comprising an assist chamber, an assist port in fluid communication with the assist chamber, and an assist portion of the vent member disposed in the assist chamber, the assist port being configured to direct inflation fluid into the assist chamber, the inflation fluid directed into the assist chamber pressurizing the assist chamber and urging the vent member to move toward the closed condition.

9. The apparatus recited in claim 8, wherein the vent member when in the open condition blocks fluid communication between the assist port and the assist chamber, the vent member permitting fluid communication between the assist port and the assist chamber when the vent member moves a predetermined distance toward the closed condition.

10. The apparatus recited in claim 1, further comprising a housing for supporting the inflator and protection device, the discharge openings being positioned within the housing and directing inflation into the protection device through a mouth portion of the protection device, the vent openings being positioned outside the housing and directing inflation fluid outside the protection device when the vent member is in the open condition.

11. The apparatus recited in claim 1, wherein the control structure comprises an end cap of the inflator, the inflator comprising an inflation fluid chamber from which inflation fluid is discharged into the end cap upon actuation of the inflator, the end cap comprising a discharge chamber including the discharge openings and a vent chamber including the vent openings, the vent member being disposed between the discharge chamber and vent chamber, the vent member blocking inflation fluid flow from the discharge chamber to the vent chamber when in the closed condition, the vent member permitting inflation fluid flow from the discharge chamber to the vent chamber when in the open condition.

12. The apparatus recited in claim 11, wherein the discharge chamber is disposed between the inflation fluid chamber and the vent chamber, the vent chamber forming a terminal end portion of the inflator.

13. The apparatus recited in claim 12, further comprising a housing for supporting the inflator and protection device, the terminal end portion of the inflator being positioned outside the housing and directing inflation fluid outside the protection device when the vent member is in the open condition.

14. The apparatus recited in claim 1, wherein the control structure comprises an end cap of the inflator, the inflator comprising an inflation fluid chamber from which inflation fluid is discharged into the end cap upon actuation of the inflator, the end cap comprising an axially extending bore, the discharge openings and vent openings extending transverse to the bore, being in fluid communication with the bore, and being spaced apart axially along the bore, the vent member being disposed between the discharge openings and vent openings, the vent member blocking inflation fluid flow through the bore to the vent openings when in the closed condition, the vent member permitting inflation fluid flow through the bore to the vent openings when in the open condition.

15. The apparatus recited in claim 14, wherein the vent openings extend through a terminal end portion of the end cap that defines a terminal end portion of the inflator.

16. The apparatus recited in claim 15, further comprising a housing for supporting the inflator and protection device, the terminal end portion of the inflator being positioned outside the housing and directing inflation fluid outside the protection device when the vent member is in the open condition.

17. An inflator for providing inflation fluid to an inflatable vehicle occupant protection device, the inflator comprising:

a housing defining an inflation fluid chamber and a gas distribution portion, the gas distribution portion being adapted to receive inflation fluid from the inflation fluid chamber and including discharge openings and vent openings; and

a vent member supported in the gas distribution portion actuatable from an open condition permitting inflation flow through the vent openings to a closed condition blocking inflation fluid flow through the vent openings.

18. The inflator recited in claim 17, wherein the gas distribution portion comprises an end cap secured to the housing, the end cap helping to define the inflation fluid chamber.

19. An apparatus for helping to protect an occupant of a vehicle, the apparatus comprising:

an inflatable vehicle occupant protection device inflatable to help protect the vehicle occupant;

an inflator for providing inflation fluid for inflating the protection device; and

a housing for supporting the protection device and inflator in the vehicle, the inflator comprising discharge openings positioned within the housing for directing inflation fluid into an inflatable volume of the protection device to inflate the protection device, the inflator further comprising a portion that extends outside the housing and comprises vent openings for venting inflation fluid outside the inflatable volume of the protection device.

20. An apparatus for helping to protect an occupant of a vehicle, the apparatus comprising:

an inflatable vehicle occupant protection device;

an inflator for providing inflation fluid for inflating the protection device; and

a tether having a first end portion connected to the protection device and an opposite second end portion connected to the inflator, the tether being configured to actuate a vent for directing inflation fluid away from the protection device.