Abstract:
A shielded electrical wire construction, comprising an insulated wire, a conductive coating surrounding the insulated wire to provide a positive attenuation of and protection from electromagnetic and radio frequency interference. The conductive coating comprises a metallic powder dispersed in a PTFE solution. An outer insulation coating formed of PTFE surrounds the conductive coating.
Abstract:
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.
Abstract:
A cable comprising at least two spaced apart conductors. The cable further comprises dielectric material surrounding the at least two conductors so as to provide dielectric material between the conductors. The cable further comprises a flexible layer comprising a composite of a resin matrix and particles, in which the flexible layer substantially surrounds the dielectric material.
Abstract:
A shielded electrical wire construction, comprising an insulated wire, a conductive coating surrounding the insulated wire to provide a positive attenuation of and protection from electromagnetic and radio frequency interference. The conductive coating comprises a metallic powder dispersed in a PTFE solution. An outer insulation coating formed of PTFE surrounds the conductive coating.
Abstract:
RFI interference has for a long time posed problems to electronic engineers, for instance, and demands a serious approach to ensure the protection of apparatus against such interference and also to avoid interference radiation by such apparatus. In his patents of EUA 3.191.132 and 3.309.633, the applicant described the basic principles of such interference suppression by means of distributed structures represented by absorbing wires (in relation with open conductor structures) and of cables (in relation with closed conductor structures), essentially using magnetic and dielectric losses in the current transmission medium and magnetic fields associated with the current conduction in these wires and cables. The principle of losses spread over distributed lines has been published in detail in IEEE Transactions on Electromagnetic Compatibility, Vol. EMC-10, n DEG 2, June 1968, p. 181 ff. These losses stem from interference attenuation by absorption, i.e. suppression along the transmission structure and, simultaneously, reduction of coupling and interference radiation of the structure.