Air bag inflator with burst disk cutter and flow control means

• US 6,131,948 A
• Filed: 03/13/1998
• Issued: 10/17/2000
• Est. Priority Date: 03/13/1998
• Status: Expired due to Fees

• Current Assignee: TRW Limited (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: TRW Limited (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Cuevas, Jess A.
• Primary Examiner(s): Dickson, Paul N.
• Application Number:
  US09/039,145
• Time in Patent Office: 949 Days
• Field of Search: 280/741, 280/742, 280/737, 137/68.21, 137/68.3, 137/68.19
• US Class Current: 280/737
• CPC Class Codes: B60R 2021/26094 characterised by fluid flow controlling valves
• CPC Class Codes: B60R 21/268 using instantaneous release of stored pressurised gas B60R21/26005 takes precedence
• CPC Class Codes: B60R 21/272 with means for increasing the pressure of the gas just before or during liberation, e.g. hybrid inflators
• CPC Class Codes: Y10T 137/1692 Rupture disc

Abstract

An apparatus (10) for inflating an inflatable vehicle occupant protection device includes a container (18) defining a chamber (16) containing fluid (14) under pressure. The container (18) has a first opening (34). A frangible portion (40) of the container (18) covers the first opening (34) and blocks fluid flow from the chamber (16). The apparatus (10) includes a second opening (50), spaced apart from the first opening (34), through which fluid can flow from the first opening to the inflatable device to inflate the inflatable device. A cutter (90) is movable in a first direction for cutting the frangible portion (40) to release fluid to flow from the chamber (16) through the first opening (34) to the second opening (50). The cutter (90) is movable in a second direction opposite the first direction for allowing an increasing flow of fluid through the second opening (50) as the cutter moves in the second direction.

Claims

1. An apparatus for inflating an inflatable vehicle occupant protection device, said apparatus comprising:

a container defining a chamber containing fluid under pressure, said container having a first opening;

said container including a frangible portion covering said first opening and blocking fluid flow from said chamber;

means for defining a second opening in said apparatus, spaced apart from said first opening, through which fluid can flow from said first opening to the inflatable device to inflate the inflatable device;

a cutter movable in a first direction for cutting said frangible portion to release fluid to flow from said chamber through said first opening to said second opening, said cutter being movable in a second direction opposite the first direction for allowing an increasing flow of fluid through said second opening as said cutter moves in the second direction; and

means for controlling the rate of flow of fluid through said second opening by resisting movement of said cutter in the second direction,

means for controlling the rate of flow of fluid through said second opening comprises an elastomeric member engageable by said cutter to resist movement of said cutter in the second direction.

2. An apparatus for inflating an inflatable vehicle occupant protection device, said apparatus comprising:

a container defining a chamber containing fluid under pressure, said container having a first opening;

said container including a frangible portion covering said first opening and blocking fluid flow from said chamber;

means for defining a second opening, spaced apart from said first opening, through which fluid can flow from said first opening to the inflatable device to inflate the inflatable device;

a movable member supported in an initial position adjacent to said frangible portion for movement relative to said frangible portion and relative to said second opening, said movable member at least partially covering said second opening when in said initial position;

actuatable means for moving said movable member from said initial position in a first direction to open said frangible portion to release fluid to flow from said chamber through said first opening to said second opening;

said movable member being movable in a second direction opposite said first direction, under the pressure of fluid from said chamber, to allow an increasing flow of fluid through said second opening as said member moves in the second direction; and

means for controlling the rate of flow of fluid through said second opening by resisting movement of said movable member in the second direction;

said means for controlling the rate of flow of fluid through said second opening comprises an elastomeric member engageable by said movable member to resist movement of said movable member in the second direction.

3. An apparatus as set forth in claim 2 wherein said elastomeric member is made from a material which pulverizes upon the application of force to said solid body in excess of a predetermined amount.

4. An apparatus as set forth in claim 2 comprising at least one extrusion orifice and wherein said elastomeric member is extruded through said at least one extrusion orifice to resist movement of said movable member in the second direction.

5. An apparatus for inflating an inflatable vehicle occupant protection device, said apparatus comprising:

a container defining a chamber containing fluid under pressure, said container having a first opening;

said container including a frangible portion covering said first opening and blocking fluid flow from said chamber;

means for defining a second opening, spaced apart from said first opening, through which fluid can flow from said first opening to the inflatable device to inflate the inflatable device;

a movable member supported in an initial position adjacent to said frangible portion for movement relative to said frangible portion and relative to said second opening, said movable member at least partially covering said second opening when in said initial position;

actuatable means for moving said movable member from said initial position in a first direction to open said frangible portion to release fluid to flow from said chamber through said first opening to said second opening;

said movable member being movable in a second direction opposite said first direction, under the pressure of fluid from said chamber, to allow an increasing flow of fluid through said second opening as said member moves in the second direction; and

means for controlling the rate of flow of fluid through said second opening by resisting movement of said movable member in the second direction;

said movable member is a cutter movable in the first direction for cutting said frangible portion to release fluid to flow from said chamber through said first opening to said second opening;

said frangible portion of said container comprises a member having a first portion welded to said container and a second portion received in a recess in said cutter prior to movement of said cutter in said first direction, said first portion of said member remaining fixed to said container after cutting of said frangible portion, said second portion of said member remaining in said recess in said cutter after cutting of said frangible portion.