Variable output using piezo valve technology

• US 20090283995A1
• Filed: 05/13/2008
• Published: 11/19/2009
• Est. Priority Date: 05/13/2008
• Status: Active Grant

• Current Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Original Assignee: Autoliv ASP Incorporated (Autoliv Incorporated)
• Inventors: Smith, Bradley W., Parks, Brent A.
• Granted Patent: US 7,784,827 B2
• Time in Patent Office: Days
• US Class Current: 280/735
• CPC Class Codes: B60R 2021/26094 characterised by fluid flow controlling valves
• CPC Class Codes: B60R 2021/2725 using a fluid fuel gas generator
• CPC Class Codes: B60R 21/268 using instantaneous release of stored pressurised gas B60R21/26005 takes precedence
• CPC Class Codes: B60R 21/274 characterised by means to rupture or open the fluid source
• CPC Class Codes: Y10T 137/1707 Disc burst after destruction of additional element

Abstract

An airbag inflator that contains a first quantity of inflation gas. This gas may be housed in a chamber. A quantity of liquid fuel may also be added. This fuel may be housed within a liquid fuel chamber. The quantity of inflation gas may operate to pressurize the liquid fuel chamber. A piezo-valve is also added. The piezo-valve seals the liquid fuel chamber. The piezo-valve is capable of variably releasing liquid fuel from the chamber such that when this secondary liquid is ignited, the airbag inflation gas can be augmented as desired.

Claims

1. An airbag inflator comprising:

a first quantity of gas;

a quantity of liquid fuel being housed within a liquid fuel chamber, the quantity of inflation gas for pressurizing the liquid fuel chamber;

a valve that seals the liquid fuel chamber, the valve for variably releasing liquid fuel from the chamber.

2. An inflator as in claim 1 wherein the valve is a piezo-valve.

3. An airbag inflator as in claim 1 further comprising an igniter that combusts the liquid fuel into a second quantity of gas that mixes with the first quantity of gas.

4. An airbag inflator as in claim 1 wherein the first quantity of gas being housed within a compressed gas chamber that is sealed by a rupture disk.

5. An airbag inflator as in claim 4 further comprising a frangible support that supports the rupture disk, frangible support being rupturable, wherein the rupture disk fails when the frangible support fails.

6. An airbag inflator as in claim 5 further comprising a piston in the liquid fuel chamber, wherein when the frangible support fails, the first quantity of gas moves the piston and applies pressure to the liquid fuel.

7. An airbag inflator as in claim 6 further comprising an initiator that operates to fail the frangible support.

8. A method for variably inflating an airbag comprising:

obtaining an airbag and an inflator, the inflator comprising;

a first quantity of gas;

a quantity of liquid fuel being housed within a liquid fuel chamber, the quantity of inflation gas being capable of pressurizing the liquid fuel chamber;

a piezo-valve that seals the liquid fuel chamber, the piezo-valve capable of variably opening the liquid fuel chamber; and

obtaining a sensor for determining the severity of a crash and communicating the severity of the crash to the piezo-valve, wherein the piezo-valve releases liquid fuel corresponding to the severity of the crash.

10. A method as in claim 9 wherein the first quantity of gas being housed within a compressed gas chamber that is sealed by a rupture disk, the inflator further comprising a frangible support that supports the rupture disk, frangible support being rupturable, wherein the rupture disk fails when the frangible support fails.

11. A method as in claim 10 further comprising a piston in the liquid fuel chamber, wherein when the frangible support fails, the first quantity of gas moves the piston and applies pressure to the liquid fuel.

12. An airbag system comprising:

a sensor that determines the severity of the crash

an inflator comprising a quantity of liquid fuel being housed within a liquid fuel chamber and an igniter that combusts the liquid fuel into a quantity of gas; and

a piezo-valve that seals the liquid fuel chamber, the piezo-valve for variably releasing liquid fuel from the chamber, wherein the piezo-valve releases an amount of liquid fuel corresponding to the severity of the crash.

13. An airbag system as in claim 12 wherein the inflator further comprises a first quantity of gas housed within a compressed gas chamber, wherein during deployment, the first quantity of gas mixes with the gas produced by combustion of the liquid fuel.

14. An airbag system as in claim 13 wherein the compressed gas chamber is sealed by a rupture disk, the inflator further comprising a frangible support that supports the rupture disk, frangible support being rupturable, wherein the rupture disk fails when the frangible support fails.

15. An airbag system as in claim 14, the inflator further comprising a piston in the liquid fuel chamber, wherein when the frangible support fails, the first quantity of gas moves the piston and applies pressure to the liquid fuel.

16. An airbag system as in claim 15, the inflator further comprising an initiator that operates to fail the frangible support.

17. An airbag system as in claim 12 further comprising an airbag, wherein the airbag may be variably inflated based upon the amount of liquid fuel released by the piezo-valve.