摘要:
The pyrotechnic ignition device of this invention comprises a hollow tubular coiled charge of pyrotechnic sheet material defining an ignition initiation position, the internal diameter of the charge decreasing and the wall thickness increasing over at least a portion of the charge extending from the initiation position in the direction of burning. This configuration enhances the reliability of ignition and the rate of flame development. Preferably the adjacent plies of the coiled charge are spaced apart. The preferred coiled charge also has a portion downstream from the initiation position in the direction of burning which decreases in external diameter and wall thickness in a direction extending away from the initiation position, the configuration of this portion being effective to enhance the speed and violence of burning of a main gas-generating propellant charge ignited by the coiled charge. In the preferred device a pyrotechnic sheet comprising a substrate of oxidizing polymeric film coated with an oxidizable metal, for example magnesium, is coiled around a cruciate axial former so that the end edges define helices. Conveniently the coiled charge may be formed by winding the sheet into a right cylindrical tubular coil and pushing out the coil axially from the centre in the direction of burning.
摘要:
An apparatus (10) for inflating an inflatable vehicle occupant protection device (36) comprises a housing (12) and an inflation fluid source (34) in the housing for, when actuated, providing fluid for inflating the protection device. An electrically actuatable initiator (38) is connected with the housing (12) for actuating the inflation fluid source (34). The apparatus (10) also comprises vehicle electric circuitry (37) for actuating the initiator (38) to actuate the inflation fluid source (34) in response to sensing an occupant protection event for which inflation of the protection device (36) is desired. A microelectromechanical system device (MEMS device) (52) in the apparatus is electrically energizable to cause actuation of the inflation fluid source (34). An autoignition mechanism (40) responsive to an event other than an occupant protection event energizes the MEMS device to cause actuation of the inflation fluid source. The MEMS device (52), when energized, generates heat for autoigniting the inflation fluid source (34) or for deactivating a secondary inflation fluid source.
摘要:
The invention provides pyrotechnic sheet material comprising a substrate of porous, vapour-permeable oxidizing polymeric film, for example a halogenopolymeric film, having a layer of oxidizable material for example magnesium, on at least part of its surface, the substrate and the oxidizable material being conjointly capable of reacting together on ignition. Advantageously at least part of the oxidizing material is accommodated within the polymer pores.The pyrotechnic sheet material burns faster than material comprising solid polymeric film.
摘要:
A vehicle occupant safety restraint gas generator is provided in which the ignition system for the propellant comprises a pyrotechnic layer (22), e.g. a reactive film, preferably comprising a substrate of oxidizing polymeric film such as polytetrafluoro-ethylene (PTFE) having at least a portion of its surface covered with a layer of oxidizable material, for example magnesium, which may be vapour-deposited on the surface. The propellant is preferably a propellant train (12, 14, 16, 18) which comprises a plurality of adjacent propellant grains such as toroidal discs which surround the pyrotechnic layer or are completeley encased thereby. The gas generator is simpler and more economical to manufacture, and has improved safety during use.
摘要:
Because of the length of the airbag gas generator that is used on the passenger side of an automotive vehicle, it has been extremely difficult and expensive to provide an ignition system that would ignite solid gas generant pellets and wafers uniformly throughout the entire length thereof. In order to effect ignition of all pellets throughout the length of the gas generator combustion chamber substantially simultaneously, there is positioned in concentric relation therein an elongated BKNO.sub.3 dipped igniter tube having similarly dipped disks positioned thereon in spaced relation, transversely thereof, BKNO.sub.3 powder initiated by a squib directs fire down the igniter tube to produce a rapid flash of fire that ignites the BKNO.sub.3 dipped igniter tube and disks and surrounding gas generant pellets. The hot gas from the gas generant pellets is cooled and filtered by a screen pack assembly prior to exiting through holes in the cylindrical wall of the gas generator and directed to an airbag for inflation.
摘要:
Inflator device assemblies wherein an igniter composition used to ignite an associated gas generant material is provided on a selected surface, such as on a damper pad, within the inflator device. Suitable igniter compositions may include a silicone resin additive effective to adhere the igniter composition to a surface within the inflator device.
摘要:
Inflator device assemblies containing an expandable fluid effective to provide a gaseous inflation medium also advantageously employ or incorporate a pyrotechnic material such as to augment or enhance at least one fill characteristic of the gaseous inflation medium. The pyrotechnic material is provided on a selected non-gas generant surface within the inflator device. Suitable pyrotechnic compositions may include a binder additive effective to adhere the pyrotechnic composition to a surface within the inflator device.
摘要:
Inflator device assemblies containing an expandable fluid effective to provide a gaseous inflation medium also advantageously employ or incorporate a pyrotechnic material such as to augment or enhance at least one fill characteristic of the gaseous inflation medium. The pyrotechnic material is provided on a selected non-gas generant surface within the inflator device. Suitable pyrotechnic compositions may include a binder additive effective to adhere the pyrotechnic composition to a surface within the inflator device.
摘要:
An apparatus (10) for inflating an inflatable vehicle occupant protection device (36) comprises a housing (12) and an inflation fluid source (34) in the housing for, when actuated, providing fluid for inflating the protection device. An electrically actuatable initiator (38) is connected with the housing (12) for actuating the inflation fluid source (34). The apparatus (10) also comprises vehicle electric circuitry (37) for actuating the initiator (38) to actuate the inflation fluid source (34) in response to sensing an occupant protection event for which inflation of the protection device (36) is desired. A microelectromechanical system device (MEMS device) (52) in the apparatus is electrically energizable to cause actuation of the inflation fluid source (34). Means (40) responsive to an event other than an occupant protection event energizes the MEMS device to cause actuation of the inflation fluid source. The MEMS device (52), when energized, generates heat for autoigniting the inflation fluid source (34) or for deactivating a secondary inflation fluid source.
摘要:
The present invention provides a gas generator for expanding and inflating a driver's seat airbag. The gas generator comprises two ignitor device 8, 9 for burning gas generants 7 packed in combustion chambers 3, 4, and enhancer device 10, 11 for allowing the flames from the ignitor device 8, 9 to be propagated circumferentially and radially of a housing 1.