Gas Generator Fitted With Pressure Regulator Means, and a Safety Device Fitted Therewith

• US 20080111359A1
• Filed: 10/19/2005
• Published: 05/15/2008
• Est. Priority Date: 10/26/2004
• Status: Active Grant

• Current Assignee: Autoliv AB (Autoliv Incorporated)
• Original Assignee: Autoliv AB (Autoliv Incorporated)
• Inventors: Abaziou, Xavier
• Granted Patent: US 7,845,679 B2
• Time in Patent Office: Days
• US Class Current: 280/741
• CPC Class Codes: B60R 2021/26094 characterised by fluid flow controlling valves
• CPC Class Codes: B60R 21/2644 using only solid reacting substances, e.g. pellets, powder
• CPC Class Codes: B60R 22/4628 characterised by fluid actuators, e.g. pyrotechnic gas generators actuating a cable B60R22/4619

Abstract

The present invention relates to a gas generator for a motor vehicle safety device, the generator comprising: a first chamber (C) for combustion containing a pyrotechnic initiator (2) and a pyrotechnic charge (3) whose combustion is triggered by said initiator; and. a second chamber (D) for diffusion into which the gas that results from combustion of said charge (3) is transferred prior to being exhausted to the outside; these two chambers (C, D) being separated from each other by a “nozzle” partition (12) presenting at least one communication orifice (13). According to the invention, said diffusion chamber (D) is provided with a piston (5) suitable for closing or not closing said orifice (13) as a function of the gas pressure in the combustion chamber (C), said piston (5) being urged to its position for closing the orifice (13) by a mass (6) of elastically deformable material, said mass (6) presenting stiffness that varies as a function of temperature, said stiffness decreasing with increasing temperature.

Claims

1-6. -6. (canceled)

7. A gas generator for a motor vehicle safety device, the generator comprising:

a first chamber for combustion containing a pyrotechnic initiator and a pyrotechnic charge to be triggered by the initiator; and

a second chamber for diffusion into which a gas that results from combustion of the charge is transferred prior to being exhausted from the gas generator, the first and second chambers being separated from each other by a nozzle partition having at least one communication orifice, the second chamber having a piston for closing and opening the orifice as a function of the gas pressure in the combustion chamber, the piston being urged to a position for closing the orifice by a mass of elastically deformable material, the mass having a stiffness that varies as a function of temperature, the stiffness decreasing with increasing temperature.

8. The generator of claim 7, wherein the mass of elastically deformable material is made of elastomer.

9. The generator of claim 7, wherein the mass includes a cylindrical pad.

10. The generator of claim 7, wherein the generator has a substantially cylindrical shape along a longitudinal axis and wherein the orifice and the piston extend on the longitudinal axis.

11. The generator of claim 7, wherein a proximal end of the piston is frustoconical.

12. The gas generator of claim 7, in combination with the safety device.

13. The gas generator of claim 12, wherein the safety device in an airbag trigger.

14. The gas generator of claim 12, wherein the safety device is a safety belt retractor.