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Publication numberUS3515518 A
Publication typeGrant
Publication dateJun 2, 1970
Filing dateAug 23, 1967
Priority dateAug 23, 1967
Publication numberUS 3515518 A, US 3515518A, US-A-3515518, US3515518 A, US3515518A
InventorsArthur M Halstead
Original AssigneeAlberta M Halstead, Osyp Nimylowicz, Us Army
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Coolant for propellant actuated gas generator
US 3515518 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

June 2, 1970 A. M. HALSTEAD ETAL 3,515,518

I COOLANT FOR PROPELLANT ACTUATED GAS GENERATOR Filed Aug. 23, 1967 INVENTORS. ARTHUR M. HALSTEAD, DECEASED BY ALBERTA MHALSTEAQADMINISTRATRIX OSYP NIMYLOW CZ BY 7n a Q '1 f g 'z I ATORNYS United States Patent Office US. Cl. 23-281 4 Claims ABSTRACT OF THE DISCLOSURE A propellant actuated gas generator having a metallic carbonyl coolant such as molybdenum-hexacarbonyl in a forward chamber and surrounding a dispersing tube for developing substantially permanent or sustaining gas pressure for inflating purposes. A first filter bed is positioned in the rearward chamber forward of the propellant and a second filter bed is located in the forward chamber forwardly of the metallic carbonyl coolant.

This invention relates to gas generators and, more particularly is a gas generator capable of developing pressure for inflating purposes.

In propellant actuated gas generators for inflating tanks, life rafts, etc., coolants heretofore employed such as salts of ammonium often contain water of crystallization. Upon heating they partially sublime and partially decompose endothermically to ammonia gas, carbon dioxide gas and water vapor, both gases being soluble in water. During initial inflation, the gases fill the tank, but only establish a temporary pressure prior to being cooled to ambient temperature whereupon the sublimed coolant solidifies, and along with the gases dissolve in the existing water condensation, all of which adversely results in a considerably reduced tank or vessel pressure.

Accordingly, one of the objects of the invention is to provide an eflicient gas generator capable of developing substantially permanent or sustaining gas pressure for inflating purposes.

Another object is to use in a gas generator a coolant which upon endothermic decomposition provides a permanent gas which is not soluble in water.

These and other objects, features and advantages will become more apparent from the following description and accompanying drawing which is a longitudinal sectional view of a preferred gas generating arrangement embodying the principles of the invention.

In the drawing the propellant actuated gas generator has a substantially hollow, cylindrical main body 11 with a laterally extending partitioning wall 12 positioned substantially mid-length thereof and defining a rearward chamber 13 containing a predetermined form of low temperature, slow burning propellant 14 and a charcoal filter bed 15 positioned forwardly of the propellant and adjacent the wall 12, as well as a forward chamber 16 that contains a preferred form of coolant 17 and a second filter bed 18 of aluminum oxide stones adjacent the forward end wall 19. Wall 19 has an appropriately apertured central protrusion 20 defining an exit port that suitably connects with a tank or other inflatable vessel 21 such as a life raft. The generator rearward end wall 22 has a central threaded opening 23 to receive a suitable attachment portion of an ignition element 24 that when appropriately actuated will ignite the propellant 14.

Partitioning wall 12 has a central fluid communicating aperture 25 the forward end of which is suitably threaded 3,515,518 Patented June 2, 1970 to mount a hollow dispersing tube 26 which is substantially closed except for a rear inlet port and a plurality of exit ports 27 distributed in predetermined spaced relationship throughout its side and forward walls.

Hot pressure gas (at approximately 2000 F.) developed upon propellant ignition passes through filter bed 15 prior to being blown into the surrounding coolant material 17 by dispersing tube 26. The coolant material, to be more fully described, is heated to a decomposition temperature of approximately 300 F. and gas products of the propellant 14 and coolant 17 are filtered through filter bed 18 prior to being delivered to the inflatable device 21 via the generator outlet port.

A preferred coolant in the form of a metallic carbonyl, such as molybdenum-hexacarbonyl Mo(CO) composition, decomposes endothermically at about 300 F. into a metallic solid and carbon monoxide gas, the latter being a permanent gas not soluble in water. The gas products of the decomposed metallic carbonyl coolant substantia ly eliminate any harmful water contribution the generator gas output, and as a result, when the gas generator delivers a predetermined pressure gas to the inflatable device, the delivered will substantially maintain the desired pressure even after cooling to ambient temperature.

It is contemplated that other metallic carbonyls, such as cobalt tetra carbonyl Co (CO) and iron nona carbonyl Fe (CO) can be satisfactorily employed to produce the desired coolant effect and sustaining gas pressure for inflating purposes.

For substantially similar test conditions for coolants in propellant actuated gas generating arrangements, the following comparative average test data was obtained for molybdenum hexacarbonyl coolant relative to a previoulsy known ammonium carbonate coolant.

Molybdenum carbonyl Max. raft pressure (at inflation)- 8.8 (23.5)

p.s. .a. Raft pressure at inflation plus 3.5 p.s.Lg. (18.2

30 min. p.s.i.a.).

Ammonium carbonate 8.9 p.s.Lg. (23.6


1.7 p.s.i.g. (16.4


77.5% retained 69.5% retained It should be noted that the 18.2 p.s.i.a. of the molybdenum carbonyl pressure will satisfactorily maintain the desired inflation, whereas the 16.4 p.s.i.a. of the ammonium carbonate developed pressure will barely satisfy the desired requirements.

Various modifications, changes or alterations may be resorted to without departing from the scope of the invention as defined in the appended claims.

We claim:

1. In a propellant gas generator having a substantially hollow main body with a laterally extending partitioning wall positioned substantially mid-length of said main body and defining forward and rearward chambers therein said wall having a central aperture therethrough,

a slow burning propellant in said rearward chamber,

a dispersing tube in said forward chamber in fluid communication with said rearward chamber and having a plurlaity of apertures, and

a metallic carbonyl composition in said forward chamber and surrounding said dispersing tube.

2. The gas generator of claim 1 wherein a filter bed is positioned in said rearward chamber forwardly of said propellant, and a second filter bed in said forward chamber forwardly of said metallic carbonyl composition.

3. The gas generator of claim 2 in which said metallic carbonyl is molybdenum-hexacarbonyl.


4. The gas generator in accordance with claim 1 wherein said metallic carbonyl is molybdenum-hexa- References Cited UNITED STATES PATENTS Millns 10239 Maurice et a1. 10239 White et a1. 23-281 Hebenstreit et a1. 23-281 XR Kowalick et a1. 23 2s1 1 4 OTHER REFERENCES 5 MORRIS O. WOLK, Primary Examiner D. G. MILLMAN, Assistant Examiner US Cl. X.R.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US2740356 *Jul 27, 1951Apr 3, 1956Rotax LtdCartridge with coolant
US2779281 *Aug 1, 1950Jan 29, 1957Maurice PierreGas generator
US3066014 *Apr 18, 1958Nov 27, 1962Hycon Mfg CompanyCool gas generator
US3122181 *Nov 3, 1961Feb 25, 1964Specialties Dev CorpGeneration of gaseous mixtures for inflatable devices
US3305319 *Apr 2, 1965Feb 21, 1967James F KowalickPropellant gas generator
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3647393 *May 11, 1970Mar 7, 1972Chrysler CorpGas-generating apparatus
US3678857 *Feb 26, 1971Jul 25, 1972Susquehanna CorpAerosol disseminator
US3785674 *Jun 14, 1971Jan 15, 1974Rocket Research CorpCrash restraint nitrogen generating inflation system
US3880595 *Aug 22, 1973Apr 29, 1975Timmerman Hubert GGas generating compositions and apparatus
US3988888 *Jun 14, 1974Nov 2, 1976The United States Of America As Represented By The Secretary Of The NavyCooler
US4013010 *Nov 4, 1974Mar 22, 1977Thiokol CorporationGas generator with expandable cartridge
US4066415 *Feb 2, 1976Jan 3, 1978Nippon Oil And Fats Co., Ltd.Gas generator for inflatable life raft
US4094028 *Mar 25, 1977Jun 13, 1978Nippon Oil And Fats Co., Ltd.Automatic inflating lifesaving buoy
US4627822 *May 20, 1985Dec 9, 1986The United States Of America As Represented By The Secretary Of The NavyLow temperature inflator apparatus
US5230216 *Jul 27, 1992Jul 27, 1993Israel SiegelMagnetic sorption self cooling and self heating containers
US5233836 *Aug 10, 1992Aug 10, 1993Israel SiegelSorption temperature changing inserts
US6051158 *Jul 30, 1998Apr 18, 2000Autoliv Asp, Inc.Coolant formulation for treating hot gas formed by an airbag inflator includes first and second ingredients which, when contacted by the hot gas, endothermically decompose to form a cooling gas and a solid and a liquid slag, binder
US6095559 *Jul 23, 1998Aug 1, 2000Autoliv Asp, Inc.Chemical cooling of airbag inflation gases
US6871873 *Feb 26, 2003Mar 29, 2005Automotive Systems Laboratory, Inc.Airbelt inflator
DE102012217718A1Sep 28, 2012Apr 4, 2013Diehl Bgt Defence Gmbh & Co. KgCold-gas pyrotechnic generator useful e.g. in fire-fighting-, driving-, or underwater rescue systems, comprises first chamber, which contains hot combustive gas generator propellant, and a second chamber containing a coolant
EP1098790A1 *Jul 19, 1999May 16, 2001Autoliv ASP, Inc.Chemical cooling of airbag inflating gases
U.S. Classification422/164, 422/167, 102/531, 102/704, 441/98, 62/4
International ClassificationC06D5/06, F42B3/04, C09K5/00
Cooperative ClassificationC06D5/06, F42B3/04, Y10S102/704, C09K5/00
European ClassificationF42B3/04, C09K5/00, C06D5/06