Gas-generating devices with grain-retention structures and related methods and systems

• US 8,672,348 B2
• Filed: 06/04/2009
• Issued: 03/18/2014
• Est. Priority Date: 06/04/2009
• Status: Active Grant

• Current Assignee: Northrop Grumman Innovation Systems, Inc. (Northrop Grumman Corporation)
• Original Assignee: Alliant Techsystems Incorporated (Northrop Grumman Corporation)
• Inventors: Robbins, Steven M., Sampson, William P.
• Primary Examiner(s): FELTON, AILEEN BAKER
• Application Number:
  US12/478,019
• Publication Number:
  US 20100307775A1
• Time in Patent Office: 1,748 Days
• Field of Search: 280/736, 280/741, 149/2
• US Class Current: 280/736
• CPC Class Codes: B60R 2021/2648 comprising a plurality of combustion chambers or sub-chambers
• CPC Class Codes: F42B 3/04 for producing gas under pressure generators of inflation fluid especially adapted for vehicle air bags B60R21/26
• CPC Class Codes: F42B 5/16 characterised by composition or physical dimensions or form of propellant charge, with or without projectile, or powder chemical composition C06B; F42B5/24 takes precedence
• CPC Class Codes: Y10T 29/494 Fluidic or fluid actuated device making

Abstract

Gas-generating devices with grain-retention structures and related methods and systems are described. In particular, gas-generating devices having at least one retention structure fixed to a frame and positioned between adjacent gas-generant grains arranged in a longitudinal stack. Fire suppression systems comprising such gas-generating devices are also described. Additionally, methods of manufacturing gas-generating devices, as well as methods of generating a gas and methods of suppressing a fire utilizing such gas-generating devices are described.

Claims

1. A gas-generating device comprising:

a plurality of gas-generant grains arranged in a longitudinally extending stack and constrained to a longitudinally stacked configuration by a frame; and

a plurality of retention plates coupled to the frame and fixed relative to the frame, each retention plate of the plurality positioned between one adjacent gas-generant grain of the plurality of gas generant grains and another adjacent gas-generant grain of the plurality of gas-generant grains in the longitudinally extending stack.

2. The gas-generating device of claim 1, wherein the retention plates each comprise a generally disc-shaped perforated metal sheet.

3. The gas-generating device of claim 2, wherein the frame comprises a sleeve having a bore sized and shaped to substantially conform to an outer surface of each gas-generant grain of the plurality of longitudinally stacked gas-generant grains and wherein each of the plurality of gas-generant grains and the plurality of retention plates are positioned within the bore of the sleeve.

4. The gas-generating device of claim 3, wherein the sleeve comprises a perforated metal pipe or tube.

5. The gas-generating device of claim 4, wherein an outer diameter of each of the plurality of retention plates is larger than an inner diameter of the bore of the sleeve and wherein each retention plate of the plurality of retention plates is positioned within the bore such that each retention plate of the plurality of retention plates is compressed by a bore wall of the sleeve forming an interference fit between each retention plate of the plurality of retention plates and the sleeve.

6. The gas-generating device of claim 5, wherein each retention plate of the plurality of retention plates comprises a plurality of cantilevered members and wherein an outer diameter of the plurality of cantilevered members prior to positioning thereof in the bore of the sleeve is larger than the inner diameter of the bore of the sleeve.

7. The gas-generating device of claim 1, wherein the frame comprises at least one rod and wherein each retention plate of the plurality of retention plates is coupled to the at least one rod and fixed to the at least one rod.

8. The gas-generating device of claim 7, wherein each retention plate of the plurality of retention plates comprises a perforated metal sheet including at least one guide aperture having a dimension smaller than a dimension of an outer surface of the at least one rod and wherein the at least one rod is positioned within the at least one guide aperture such that a region of the perforated metal sheet surrounding the at least one guide aperture is compressed by the outer surface of the at least one rod and forms an interference fit between each retention plate of the plurality of retention plates and the at least one rod.

9. The gas-generating device of claim 1, wherein each retention plate of the plurality of retention plates has a shape similar to a shape of a cross-section of each gas-generant grain of the plurality of gas-generant grains.

10. A gas-generating device comprising:

longitudinally stacked gas-generant grains;

a frame constraining the gas-generant grains to a longitudinally stacked configuration; and

retention structures coupled to the frame, each retention structure positioned between adjacent gas-generant grains, the retention structures sized and configured to remain fixed to the frame and constrain the longitudinal position of the adjacent gas-generant grains relative to the frame as the adjacent gas-generant grains in the longitudinal stack generate gas.

11. The gas-generating device of claim 10, wherein the retention structures are positioned between two gas-generant grains of the longitudinally stacked gas-generant grains.

12. The gas-generating device of claim 10, further comprising an interference fit coupling the retention structures to the frame.

13. A fire suppression system comprising:

at least one combustion chamber;

at least one effluent train coupled to the at least one combustion chamber; and

at least one gas-generating device located within the at least one combustion chamber, the at least one gas-generating device comprising;

a plurality of gas-generant grains arranged in a longitudinal stack and constrained to a longitudinally stacked configuration by a frame; and

a plurality of retention plates coupled to the frame and fixed relative to the frame, each retention plate of the plurality positioned between one adjacent gas-generant grain and another adjacent gas-generant grain of the plurality of gas-generant grains in the longitudinal stack.

14. A method of manufacturing a gas generator, the method comprising:

arranging a plurality of gas-generant grains in a longitudinal stack;

positioning retaining members between an adjacent gas-generant grain and another adjacent gas-generant grain of the plurality of gas-generant grains in the longitudinal stack;

constraining the plurality of gas-generant grains to a longitudinally stacked configuration using a frame; and

fixing the retaining members to the frame.

15. The method of claim 14, further comprising aligning a feature of each gas-generant grain with a retaining feature of the frame.

16. The method of claim 15, wherein aligning a feature of each gas-generant grain with a retaining feature of the frame comprises aligning an arcuate outer surface of each gas-generant grain with a bore of a sleeve.

17. The method of claim 15, wherein aligning a feature of each gas-generant grain with a retaining feature of the frame comprises aligning at least one aperture of each gas-generant grain with at least one rod.

18. The method of claim 15, further comprising:

sliding a feature of a first gas-generant grain along the retaining feature of the frame to position the first gas-generant grain at a first longitudinal position relative to the frame;

sliding a first retaining member to a second longitudinal position relative to the frame adjacent a surface of the first gas-generant grain;

fixing the first retaining member to the frame at the second longitudinal position by compressing at least a portion of the first retaining member with the frame to form an interference fit between the first retaining member and the frame; and

sliding an alignment feature of a second gas-generant grain along the retaining feature of the frame to position the second gas-generant grain adjacent to the first gas-generant grain and position the first retaining member between the adjacent first gas-generant grain and second gas-generant grain.

19. A method of generating a gas, the method comprising:

combusting a plurality of longitudinally stacked gas-generant grains to generate a gas;

restricting lateral movement of the plurality of longitudinally stacked gas-generant grains during combustion with a frame structure; and

restricting longitudinal movement of at least some of the plurality of longitudinally stacked gas-generant grains during combustion by maintaining retaining members between adjacent gas-generant grains of the plurality of longitudinally stacked gas-generant grains and maintaining the retaining members fixed relative to the frame structure during combustion.

20. The method of claim 19, wherein combusting a plurality of longitudinally stacked gas-generant grains to generate a gas comprises combusting a plurality of longitudinally stacked gas-generant grains to generate a fire-suppressing gas.