US 5,763,814 A · Electrical initiator

Abstract

The invention relates to an electrical initiator which can be used with an automobile air bag or seat belt pretensioner. The initiator comprises a header, a cup, conducting pins, epoxy pin seals, a bridgewire, a primer, and an output charge. The header and the cup are composed of an insulating dielectric material capable of being ultrasonically welded together. The header secures the pins. Each pin is electrically conductive and each is formed with a buttress knurl to form a seal when each pin is inserted into the header. Additionally, the pins are further sealed to the header by an epoxy sealant. The bridgewire connects the pins together on one side of the header. An electrical signal through the bridgewire generates heat igniting the primer. Primer reacts with the output charge that in turn ignites a solid gas generant that produces gas that fills air bags or activates the gas generator that drives seat belt pretensioners. The primer contacts the bridgewire. The output charge contacts the primer. The output charge is in the cup, and the cup is ultrasonically welded to the header to provide, along with the pin seals, an environmentally secure seal.

Claims25

Dependent claims

An electrical initiator for initiating ordnance, comprising:

a plastic header;
at least two non-insulated pins each having a knurled section, traversing and engaging the plastic header;
means for connecting said at least two pins to the header wherein the means includes the plastic header establishing and maintaining a sealing force between the header and the pins to form a reliable environmental seal for surviving an automotive environment, said means including said knurled section on each of said pins;
a plastic output cup;
one of a thermal weld and an ultrasonic weld for attaching the plastic output cup to the plastic header to form a second seal such that the plastic header, the plastic output cup, the at least two pins, the seal and the second seal form a reliable environmentally sealed enclosure for surviving an automotive environment;
an electrically resistive device attached to said at least two pins;
and
a resilient primer in the enclosure and in contact with said electrically resistive device wherein the resilient primer withstands any mechanical shock caused when attaching the plastic output cup to the plastic header using the one of the thermal weld and the ultrasonic weld.

5 more elements

Dependencies are inferred from the claim text.

Electrical initiator

Life of this patent

Electrical initiator

Life of this patent

Abstract

Claims25