Ammunition and explosives – Igniting devices and systems – Electrical primer or ignitor
Reexamination Certificate
1998-10-26
2001-10-23
Miller, Edward A. (Department: 3641)
Ammunition and explosives
Igniting devices and systems
Electrical primer or ignitor
C102S202700, C149S019920
Reexamination Certificate
active
06305286
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to an igniter and method of making an igniter, and particularly relates to an igniter for use with an inflator for inflating an inflatable vehicle occupant protection device.
BACKGROUND OF THE INVENTION
An inflatable vehicle occupant protection device, such as an air bag, is inflated by inflation gas provided by an inflator. The inflator contains a body of ignitable gas generating material. The inflator further includes an igniter to ignite the gas generating material.
The igniter contains a charge of ignition material. The igniter also contains a bridgewire which is supported in a heat transferring relationship with the ignition material. When the igniter is actuated, an actuating level of electric current is directed through the bridgewire in the igniter. This causes the bridgewire to become resistively heated sufficiently to ignite the ignition material. The ignition material then produces combustion products which, in turn, ignite the gas generating material.
SUMMARY OF THE INVENTION
The present invention is an electrically actuatable igniter which comprises a body, a pair of electrodes in the body, a heating element electrically connected between the electrodes, and a dome shaped ignition droplet covering and adhering to the heating element. The ignition droplet comprises an intimate mixture of a cured free-radical resin binder, which is at least substantially cured in situ by ultraviolet radiation, and a particulate pyrotechnic material in a substantial proportion effective for sustained combustion in the mixture. The resin binder prior to curing is a liquid and has a surface tension, viscosity, and wetability with the heating element effective to achieve the dome configuration.
Further, in accordance with the present invention, the electrically actuatable igniter is made by a method which comprises providing a body, locating a pair of electrodes in the body, electrically connecting a heating element between the electrodes, and adhering a dome shaped ignition droplet to the heating element. The ignition droplet comprises an intimate mixture of a cured free-radical resin binder, which is at least substantially cured in situ by ultraviolet radiation, and a particulate pyrotechnic material in a substantial proportion effective for sustained combustion in the mixture. The resin binder prior to curing is a liquid and has a surface tension, viscosity, and wetability with the heating element effective to achieve the dome configuration.
The pyrotechnic material has a reddish-orange color and absorbs ultraviolet radiation. It was found, in accordance with the present invention, that by providing the ignition droplet with the dome configuration prior to curing, the penetration distances necessary for at least substantial curing of the free-radical resin binder in the ignition droplet by ultraviolet radiation were reduced enough to achieve the substantial curing despite absorption of the radiation by the pyrotechnic material.
REFERENCES:
patent: 1890112 (1932-12-01), Fisher
patent: 2821139 (1958-01-01), Apstein et al.
patent: 2900242 (1959-08-01), Williams et al.
patent: 3017300 (1962-01-01), Herring
patent: 3462952 (1969-08-01), D'Alelio
patent: 3572247 (1971-03-01), Warshall
patent: 3999484 (1976-12-01), Evans
patent: 4025591 (1977-05-01), Pendergast
patent: 4767577 (1988-08-01), Muller et al.
patent: 5348344 (1994-09-01), Blumenthal et al.
patent: 5353707 (1994-10-01), Duguet
patent: 5369955 (1994-12-01), VanName et al.
patent: 5403036 (1995-04-01), Zakula et al.
patent: 5470104 (1995-11-01), Smith et al.
patent: 5648634 (1997-07-01), Avory et al.
patent: 5665276 (1997-09-01), Kirby et al.
patent: 5750922 (1998-05-01), Seeger
patent: 5939660 (1999-08-01), Fogle
Chatley, Jr. Glenn Raymond
Fogle, Jr. Homer William
Miller Edward A.
Tarolli, Sundheim, Covell Tummino & Szabo L.L.P.
TRW Inc.
LandOfFree
Preparation of an igniter with an ultraviolet cured ignition... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Preparation of an igniter with an ultraviolet cured ignition..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Preparation of an igniter with an ultraviolet cured ignition... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2563366