Abstract: A method of making an ignition device and center wire assembly that includes first, second and third electrode members, a conductive seal, and a noise suppressing seal. The method locates the first electrode member at an axial end of the center wire assembly near a spark gap and the third electrode member at an axial end of the center wire assembly such that it receives an electrical ignition pulse and a second electrode member between the first and third electrode members. Furthermore, the method locates the conductive seal between the first and second electrode members and the noise suppressing seal between the second and third electrode members.

Abstract: A spark plug includes an electrode which during assembly is inserted into a vertical bore of a ceramic insulator from beneath. The electrode has an expanded firing end protruding from the insulator bottom. Tabs at an upper end of the electrode are expanded inside the bore to engage the insulator, and this is done using a removable expanding tool inserted into the insulator. A conductive glass in granular form is poured into the bore and envelops the expanded upper end of the electrode. A sacrificial conductive push pin inserts into the upper bore over the glass granules. The sub-assembly is heated to melt the glass and the push pin is pressed down into the melted glass. Upon cooling, the glass within the insulator fuses forming a seal which further strengthens the flared engagement of the electrode to the insulator.

Abstract: A spark plug center wire assembly that includes a noise suppressing conductive seal with improved isolation of the seal from the heat generated at the firing end of the spark plug. The center wire assembly includes a firing electrode, a conductive glass seal, an intermediate electrode, the noise suppressing glass seal, and a terminal electrode. By locating the firing electrode, conductive seal and intermediate electrode between the noise suppressing seal and the spark gap, the center wire assembly is able to utilize the noise suppression attributes of the suppressive seal, while distancing the seal from the high temperatures created during the combustion process. A method of manufacturing the same is also disclosed in which the two glass seals are formed by sequential firing operations.