Circuit assembly for exhaust emission monitoring

Abstract

A device for monitoring the composition of the exhaust emission of a combustion process includes a hollow elongated body open at one end thereof and an elongated substrate located in the body and defining adjacent the one end of the body an exhaust emission sensing element and a resistive heating element. The sensing element and the heating element are printed on opposite sides of one end of the substrate and are electrically connected to respective first conductive areas extending to the opposite end of the substrate. A carrier is mounted in the other end of the body and supports at least two terminal members which are electrically connected to respective second conductive areas provided on first and second elongated, flexible circuit elements which at their free ends project from the carrier and are folded inwardly so that said second conductive areas are presented to each other. The other end of the substrate is interposed between the folded portions of the first and second circuit elements so that said second conductive areas are aligned with said first conductive areas respectively, and a locating sleeve is engaged with said carrier so that said substrate and said folded portions of the first and second circuit elements extend through the sleeve. At least one clamping member is urged into a channel defined in the sleeve to trap the folded portions of said first and second circuit elements against the substrate. The first and second conductive areas are thereby urged into electrical contact with each other to electrically connect said terminal members to said sensing element and said resistive element respectively.