Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.

Patents

  1. Advanced Patent Search
Publication numberUS3810655 A
Publication typeGrant
Publication dateMay 14, 1974
Filing dateAug 21, 1972
Priority dateAug 21, 1972
Publication numberUS 3810655 A, US 3810655A, US-A-3810655, US3810655 A, US3810655A
InventorsPrachar O
Original AssigneeGen Motors Corp
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Gas generator with liquid phase cooling
US 3810655 A
Abstract
A cylindrical housing has one closed end wall and an opposite end wall provided with an atomizing nozzle and a pair of concentric rows of nozzles encircling the atomizing nozzle. A flexible container within the housing contains a mixture of water and ethyl alcohol. A conduit connects the atomizing nozzle and the container. A charge of propellant material is located within the housing. When the charge is ignited, the hot gases compress the container to force the liquid therein through the conduit and the atomizing nozzle to atomize the liquid. The droplets mix with the hot gases flowing through the concentric rows of nozzles to cool the gases as the gases flow to an inflatable occupant restraint cushion.
Images(1)
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

United States Patent 1191 1111 3,810,655 Pracher May 14, 1974 [54] GAS GENERATOR WITH LIQUID PHASE 3,483,695 12/1969 Olsen ZZZ/386.5

COOLING Primary Examiner--David Schonberg l [75] mentor (Lake: P PgghglLOYMlgh Assistant Exammer.lohn P. S1lverstr1m [73] Assignee: General Motors Corporation, Attorney, Agent, or Firm-Herbert Furman Detroit, Mich.

[22] Filed: Aug. 21, 1972 [57] ABSTRACT {21] Appl. No.: 282,069 A cylindrical housing has one closed end wall and an opposite end wall provided with an atomizing nozzle and a pair of concentric rows of nozzles encircling the [52] 280/150 35 5 42 2 atomizing nozzle. A flexible container within the hous- 51 I t Cl l ing contains a mixture of water and ethyl alcohol. A i conduit connects the atomizing nozzle and the con- 1 o earc 23 l 4 tainer. A charge of propellant material is located within the housing. When the charge is ignited, the hot gases compress the container to force the liquid [56] References Cned therein through the conduit and the atomizing nozzle UNITED STATES PATENTS to atomize the liquid. The droplets mix with the hot 3,692,495 9/1972 Schneiter et al 141/4 gases flowing through the concentric rows of nozzles 3,091,923 6/1963 Barnes 222/3865 to cool the gases as the gases flow to an inflatable oc- 3,283.962 11/1966 Whitmore.... 222/3 cupam restraint Cushion 3,731,843 5/1973 Anderson 280/150 AB 3,308,818 3/1967 Rutkowski 222/3865 2 Claims, 1 Drawing Figure RESTRAINT RESTRAINT F CUSH ION SENSOR This invention relates to gas generators with liquid phase cooling and particularly to such gas generators intended primarily for use with inflatable occupant restraint cushions.

It is well known to use gas generators for inflation of inflatable occupant restraint cushions. Such gas generators contain a charge of propellant material which is ignitable to generate gases for inflating the cushion. Generally the charge of propellant material consists primarily of black powder although it may be admixed with other materials. The ignition of the gas generator is controlled by either inertia type or acceleration type sensors. The sensors are mounted on the vehicle and are actuated when impact of the vehicle with an obstacle generates an acceleration pulse of predetermined amplitude and time or the vehicle experiences a predetermined change of velocity.

The generated gases are of high pressure and high temperature. Since the gases inflate the occupant restraint cushion, it is well known to mix the propellant gases within the gas generator with either liquid materials or endothermic compounds in order to decrease the temperature of the gases so that the temperature of the cushion remains below a certain limit.

The gas generator of this invention uses liquid phase cooling to cool the high pressure, high temperature gases before the gases flow to the occupant restraint cushion. The mixing occurs exteriorly of the gas generator by the intermixing of the generated gas with atomized liquid. Since the droplets of liquid have a large surface-to-volume ratio, the evaporation rate is greatly increased when the droplets are mixed with the generated gases.

The evaporation rate is important since a high rate of heat transfer must occur between the generated gases and the liquid within a very short time period, such as 30 to 40 milliseconds.

One of the features of this invention is that it provides an improved gas generator with liquid phase cooling wherein high temperature, high pressure gases generated by the ignition of a charge of propellant material compress a flexible container containing liquid to force the liquid through an atomizing nozzle and mix the resultant droplets with the gases flowing from the genera tor to an inflatable occupant restraint cushion to thereby cool the gases. Another feature of this invention is that it provides such a gas generator wherein the atomizing nozzle is encircled by other nozzles through which the hot gases flow to the cushion to ensure a high degree of mixing between the droplets and the hot gases. A further feature of this invention is that the flexible container is axially remote from the atomizing nozzle and communicates with the nozzle through a conduit passing through the charge.

These and other features of the invention will be readily apparent from the following specification and drawing wherein:

The FIGURE is a sectional view of a gas generator according to this invention.

Referring now to the drawing, a gas generator designated generally includes a cylindrical vessel or housing 12 having a closed dome type end wall 14. The axial wall of housing 12 is externally threaded at 16, and an 2 internally threaded cap or housing closure 18 is threaded thereto to close the housing.

The closure 18 includes first and second concentric rows of circumferentially spaced nozzles 20 and 22 which are shown as openings through the closure wall. The nozzles 20 and 22 may be arranged in any pattern, such as in radial alignment with each other or staggered with respect to each other. Any type of removable seal 24, such as tape, normally covers the rows of nozzles. The closure 18 further includes a convergent type opening 26. A suitable pressure rupturable seal 28, such as one of rubber, as shown, or thin metal, closes the opening 26. The seal is staked at 3.0 to the closure.

A flexible container 32 fits within the housing 12 and conforms to the axial wall thereof and the end wall 14 thereof. The container 32 may be made of any suitable material, such as neoprene type rubber, and is filled with liquid 34, such as a mixture of ethyl alcohol and water. I

A cylindrical tube or conduit 36 has the upper end thereof received within a cylindrical axial flange 38 of the closure 18. A swirl nozzle 40 is received within the upper end of the conduit and cooperates with the convergent opening 26 to provide an atomizing nozzle. The neck or outlet 42 of the container 32 receives the conduit and isconventionally clamped thereto at 44 to provide a pressure seal between the container and the conduit. The conduit further includes a number of radial openings 46 which communicate the interior of the conduit with the container 32. The lower end of the conduit opens to the container.

A charge 48 of propellant material, such as conventional black powder with other ingredients, is contained within the housing 12 between the flexible container 32 and the closure 18. As shown, the charge annularly surrounds the neck 42 of the container and the tube 36. A conventional igniter 50 is provided for igniting the charge. The igniter is conventionally connected across a sensor 52 and a source of power.

As is well known in the art of vehicleoccupant'restraint systems, the vehicle includes redundant inertial type sensors or acceleration sensors, or combinations of these, which sense impacts of the vehicle with an obstacle of a magnitude sufficient to generate acceleration pulses of predetermined amplitude and time or predetermined changes in vehicle velocity. When such pulses or changes occur, the sensors actuate the restraint system.

Assuming now that the sensor 52 is actuated due to impact of the vehicle with an obstacle, the charge 48 will be ignited by the igniter 50 to generate volume of high temperature, high pressure gas. The generated gas will flow through the nozzles 20 and 22 and into the schematically indicated manifold 54 which is threaded to closure 18. The manifold conventionally communicates with the inflatable occupant restraint cushion 56. The manifold and cushion are conventional and it is believed that the details thereof are known to those skilled in the art.

The generated gas will additionally act upon the flexible container 32 to compress or squeeze this container so that the liquid 34 will be forced through'theopenings 46' and the lower open end of the tube and upwardly of the tube. As the liquid is forced upwardly of the tube, it will flow through the swirl nozzle 40 an but through the opening and be atomized. The droplets will mix with the hot gases passing through the nozzles 20 and 22 and be evaporated so as to cool the hot gases so that the temperature of the gases flowing to the cushion 56 through the manifold 54 will be below a preset maximum. The container 32 will be collapsed against the tube when all of the generated gas has flowed to the cushion.

Conventionally, the inflator has a time budget of approximately 30 to 40 milliseconds in which to generate the volume of gas. Thus, heat transfer must take place at an extremely high rate in order for the generated gas to be cooled below a certain temperature before the gas inflates the cushion 56. By forcing the liquid 34 through an atomizing nozzle to disperse the liquid into fine droplets, a large surface-tovolume ratio is obtained and this, of course, enhances the evaporation rate and likewise increases the temperature drop in the gases flowing through the nozzles and 22. By dispersing the liquid into fine droplets and by mixing the droplets with the hot gases exteriorly of the gas generator, the gas generator of this invention reduces the temperature of the gas to that desired prior to the time that the gas flows to the cushion 56.

Thus, this invention provides an improved gas generator with liquid phase cooling.

1 claim:

1. A gas generator comprising, in combination, a generally cylindrical housing having end walls, one being provided with an axially located first atomizing nozzle means and an encircling series of radially spaced second nozzle means, a flexible container containing atomizable liquid and located within the housing adjacent the other end wall, conduit means extending axially of the housing from within the container to the first nozzle means, an ignitable charge surrounding the conduit means and located adjacent the one end wall in communication with the second nozzle means, ignition of the charge generating high pressure, high temperature gas within the housing, the gas providing an axial compressing force on the flexible container to force the liquid therein through the conduit means and the first nozzle means and atomize the liquid in droplets, the droplets mixing with the generated gas flowing through the second nozzle means to cool the gas, and means communicating the first and second nozzle means with an inflatable occupant restraint cushion.

2. A gas generator comprising, in combination, a generally cylindrical housing having end walls, one being provided with an axially located atomizing nozzle and an encircling series of radially spaced second nozzles, a flexible container containing atomizable liquid and located within the housing adjacent the other end wall, a conduit extending axially of the housing from within the container to the atomizing nozzle, means sealing the container to the conduit, an annular ignitable charge surrounding the conduit and sealing means and located adjacent the one end wall in communication with the second nozzles, ignition of the charge generating high pressure, high temperature gas within the housing, the gas providing an axial compressing force on the flexible container -to force the liquid therein through the conduit and the atomizing the nozzle and atomize the liquid in droplets, the droplets mixing with the generated gas flowing through the second nozzles to cool the gas, and means communicating the atomizing nozzle and second nozzles with an inflatable occupant restraint cushion.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3091923 *Dec 20, 1960Jun 4, 1963Barnes Paul TLiquid propellant tankage
US3283962 *Sep 9, 1964Nov 8, 1966Whitmore Max EThree-position valve for aerosol container having a chamber with spaced inlets from container interior
US3308818 *Jul 24, 1964Mar 14, 1967Rutkowski Eugene VInjection cartridge
US3483695 *Apr 25, 1967Dec 16, 1969Charles R OlsenActuator
US3692495 *Jun 19, 1970Sep 19, 1972Thiokol Chemical CorpGas generator
US3731843 *Jun 10, 1971May 8, 1973Susquehanna CorpGas source
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4050483 *Oct 14, 1975Sep 27, 1977Allied Chemical CorporationInflation surge delay
US4358998 *Feb 4, 1980Nov 16, 1982Thiokol CorporationIgniter for a pyrotechnic gas bag inflator
US4531607 *May 31, 1984Jul 30, 1985General Motors CorporationVehicle windshield lubrication system
US5330730 *Oct 28, 1992Jul 19, 1994Dynamit Nobel AgGas generator for an inflatable impact cushion for protecting an occupant of a motor vehicle from injury
US5351527 *Dec 4, 1992Oct 4, 1994Trw Vehicle Safety Systems Inc.Method and apparatus for testing fluid pressure in a sealed vessel
US5401340 *Jan 10, 1994Mar 28, 1995Thiokol CorporationBorohydride fuels in gas generant compositions
US5429691 *Jan 5, 1994Jul 4, 1995Thiokol CorporationThermite compositions for use as gas generants comprising basic metal carbonates and/or basic metal nitrates
US5439537 *Aug 10, 1993Aug 8, 1995Thiokol CorporationThermite compositions for use as gas generants
US5460406 *Dec 13, 1993Oct 24, 1995Trw Vehicle Safety Systems Inc.Inflator assembly
US5492364 *Aug 15, 1994Feb 20, 1996Automotive Systems Laboratory, Inc.Rupturable plastic housing for an air bag inflator
US5584505 *Apr 29, 1996Dec 17, 1996Trw Inc.Inflator assembly
US5591900 *Sep 23, 1994Jan 7, 1997Trw Vehicle Safety Systems Inc.Method and apparatus for testing fluid pressure in a sealed vessel
US5592812 *Feb 9, 1996Jan 14, 1997Thiokol CorporationMetal complexes for use as gas generants
US5656779 *Jan 26, 1995Aug 12, 1997Trw Inc.Apparatus and method for producing structural and acoustic vibrations
US5662352 *Sep 27, 1995Sep 2, 1997Trw Inc.Swaged annular support for air bag inflator closure and method
US5673935 *Jun 7, 1995Oct 7, 1997Thiokol CorporationMetal complexes for use as gas generants
US5725699 *Jul 26, 1995Mar 10, 1998Thiokol CorporationMetal complexes for use as gas generants
US5735118 *Aug 16, 1996Apr 7, 1998Thiokol CorporationUsing metal complex compositions as gas generants
US5762369 *Apr 26, 1995Jun 9, 1998Hi-Shear Technology CorporationAir bag inflator using liquid monopropellant and adaptable to produce ouputs with various parameters
US5779269 *Dec 6, 1996Jul 14, 1998Olin CorporationPropellant module assembly
US5907120 *Dec 2, 1996May 25, 1999Hi Shear Technology CorporationInflator for vehicle air bags
US5951043 *Nov 24, 1997Sep 14, 1999Hi-Shear Technology CorporationAir bag inflator using liquid monopropellant and adaptable to produce outputs with various parameters
US6076468 *Mar 26, 1998Jun 20, 2000Atlantic Research CorporationSolid propellant/water type hybrid gas generator
US6196583Jun 19, 1998Mar 6, 2001Trw Airbag Systems Gmbh & Co. KgGas generator with cooling device
US6279948Oct 19, 1999Aug 28, 2001Bayerische Motoren Werke AktiengesellschaftMethod and system for triggering an airbag
US6390499 *Aug 28, 1998May 21, 2002Autoliv Development AbGas bag arrangement with a gas guide housing comprising partial discharge areas
US6412814Aug 4, 1999Jul 2, 2002Trw Airbag Systems Gmbh & Co. KgGas generator with controllable fluid injection
US6439604 *Jan 26, 2000Aug 27, 2002Trw Inc.Side curtain assembly including fill tube
US6481357 *Nov 26, 1999Nov 19, 2002Trw Airbag Systems Gmbh & Co. KgGas generator for a safety system
US6481746Nov 7, 1996Nov 19, 2002Alliant Techsystems Inc.Metal hydrazine complexes for use as gas generants
US6626115 *Feb 9, 2001Sep 30, 2003Trw Airbag Systems Gmbh & Co. KgGas generator
US6969435Feb 18, 1998Nov 29, 2005Alliant Techsystems Inc.Metal complexes for use as gas generants
US7686329 *Apr 11, 2008Mar 30, 2010Takata-Petri AgAirbag module for a motor vehicle
US7690680Aug 29, 2008Apr 6, 2010Takata-Petri AgAirbag module
US7770924Jul 17, 2008Aug 10, 2010Autoliv Asp, Inc.Liquid cooled hybrid
US7857345Jul 7, 2008Dec 28, 2010Tk Holdings, Inc.Valve assembly for gas generating system
US7887091Mar 12, 2010Feb 15, 2011Autoliv Asp, Inc.Additives for liquid-cooled inflators
US7896393Feb 18, 2010Mar 1, 2011Takata-Petri AgAirbag module
US7914040Apr 28, 2008Mar 29, 2011Tk Holdings, Inc.Cold gas generating system
US7946617 *Feb 18, 2010May 24, 2011Takata-Petri AgAirbag module
US7963555Feb 5, 2010Jun 21, 2011Takata-Petri AgAirbag module for motor vehicle
US8025310Feb 18, 2010Sep 27, 2011Takata-Petri AgAirbag module
US8029018Feb 18, 2010Oct 4, 2011Takata-Petri AgAirbag module
US8047568Feb 18, 2010Nov 1, 2011Takata-Petri AgAirbag module
US8113542Jan 22, 2009Feb 14, 2012Tk Holdings, Inc.Pressurized gas release mechanism
US8123878Jun 2, 2008Feb 28, 2012Tk Holdings, Inc.Gas generating system
US8162350 *Oct 7, 2010Apr 24, 2012Autoliv Asp, Inc.Gas generator
US8297652 *Jan 13, 2010Oct 30, 2012Tk Holdings, Inc.Gas generating system
US8764054Feb 4, 2010Jul 1, 2014Tk Holdings Inc.Gas generating system
US8794665 *Sep 14, 2012Aug 5, 2014Trw Airbag Systems GmbhInflator, module including an inflator, vehicle safety system and method of operating a vehicle occupant protection system
US20100176580 *Jan 13, 2010Jul 15, 2010Tauchen Dale EGas Generating System
US20130087065 *Sep 14, 2012Apr 11, 2013Trw Airbag Systems GmbhInflator, module including an inflator, vehicle safety system and method of operating a vehicle occupant protection system
CN101341049BMar 5, 2007Mar 2, 2011高田-彼得里公开股份有限公司Airbag module for a motor vehicle
DE19726276A1 *Jun 20, 1997Dec 24, 1998Temic Bayern Chem Airbag GmbhGas generator with device for producing fluid film
DE19726296A1 *Jun 20, 1997Dec 24, 1998Temic Bayern Chem Airbag GmbhGasgenerator mit Kühlvorrichtung
DE19753074C1 *Nov 29, 1997Jun 10, 1999Tieu Anh DungGas generator for a vehicle safety system
DE19849027A1 *Oct 23, 1998Apr 27, 2000Bayerische Motoren Werke AgVerfahren zum Zünden eines Airbags
EP0468724A1 *Jul 22, 1991Jan 29, 1992General Electric CompanyLiquid propellant inflator for vehicle occupant restraint apparatus
EP0685367A2 *Mar 10, 1995Dec 6, 1995HS Technik und Design Technische Entwicklungen GmbHGas generator
EP0715996A1 *Nov 30, 1995Jun 12, 1996Martin Marietta CorporationRestraint apparatus
EP0788942A2 *Aug 1, 1996Aug 13, 1997Morton International, Inc.Liquid-fueled, porous-piston-actuated, inflator for an airbag inflatable restraint system
EP0978424A2 *Aug 3, 1999Feb 9, 2000TRW Airbag Systems GmbH & Co. KGGas generator with controlable liquid injection
EP0995643A2 *Sep 17, 1999Apr 26, 2000Bayerische Motoren Werke AktiengesellschaftMethod for inflating an airbag
EP1004484A2 *Nov 25, 1999May 31, 2000TRW Airbag Systems GmbH & Co. KGGas generator for a safety system
EP2019003A1 *Mar 5, 2007Jan 28, 2009Takata-Petri AGAirbag module for a motor vehicle
EP2019004A1 *Mar 5, 2007Jan 28, 2009Takata-Petri AGAirbag module for a motor vehicle
EP2036785A1 *Mar 5, 2007Mar 18, 2009Takata-Petri AGAirbag module for a motor vehicle
EP2048042A1 *Mar 5, 2007Apr 15, 2009Takata-Petri AGAirbag module for a motor vehicle
WO1996005083A1 *Oct 25, 1994Feb 22, 1996Automotive Systems LabRupturable plastic air bag inflator housing
WO1997048581A1 *Jun 16, 1997Dec 24, 1997Hi Shear Technology CorpInflator for vehicle air bags
WO1998026954A2 *Nov 17, 1997Jun 25, 1998Olin CorpPropellant module assembly
WO1998058824A1 *Jun 19, 1998Dec 30, 1998Trw Airbag Sys Gmbh & Co KgGas generator with cooling device
WO2007101644A1 *Mar 5, 2007Sep 13, 2007Takata Petri AgAirbag module for a motor vehicle
WO2009103380A1 *Dec 18, 2008Aug 27, 2009Takata-Petri AgAirbag module for a motor vehicle
Classifications
U.S. Classification280/736, 102/346, 422/165, 422/167, 102/531, 222/386.5, 222/3
International ClassificationB60R21/264, B60R21/26
Cooperative ClassificationB60R21/264
European ClassificationB60R21/264