IMPROVED ELECTRICAL WIRING ASSEMBLY

摘要

A method of improving an electrical wiring assembly for a device such as vehicle airbag pyrotechnic actuator by replacing the usual twisted pair of wires by an untwisted pair of wires for greater ease of constructing the wiring harness, while the attenuation of parasitic signals is maintained or enhanced because at least one of the untwisted wires is at least partly enclosed (preferably substantially completely enclosed) in: a) an inner layer of a high-dielectric polymeric composition, preferably PVDF, which inner layer is at least partly enclosed (preferably substantially completely enclosed) in b) an overlying lossy layer at least partly composed or oganic polymeric material, preferably thermoplastic elastomer and/or ferrite, and which lossy layer is least partly enclosed (preferably substantially completely enclosed) in c) an overlying electrically-insulating polymeric jacket layer, preferably ETFE or polyester, wherein the layers are capable of acting as a parallel filter to attenuate (preferably by more than 20dB per metre, more preferably at least 25dB per metre) parasitic signals: i) at electrostatic discharge frequencies of less than 300 MHz, preferably also at frequencies less than 200 MHz, more preferably also at frequencies in the range below 100 MHz, especially 50-100 MHz or 1-10 MHz, or ii) at EMI frequencies greater than 300 MHz, preferably also at frequencies greater than 500 MHz, more preferably also at frequencies greater than 1000 MHz.