Abstract:
An ignitor assembly constructed in accordance with one aspect of the invention has an upper inductor subassembly coupled to a lower firing end subassembly for relative pivot movement between the subassemblies. The upper inductor subassembly includes a tubular housing with inductor windings received therein with an upper electrical connector adjacent an upper end of the housing and a lower electrical connector adjacent a lower end of the housing. The lower firing end subassembly includes a ceramic insulator and a metal housing surrounding at least a portion of the ceramic insulator. The ceramic insulator has an electrical terminal extending from a terminal end and an electrode extending from a firing end. A flexible tube couples the upper inductor subassembly to the lower firing end subassembly and maintains the electrical terminal of the lower firing end subassembly in electrical contact with the lower electrical connector of the upper at a pivot joint.
Abstract:
An ignitor assembly constructed in accordance with one aspect of the invention has an upper inductor subassembly coupled to a lower firing end subassembly for relative pivot movement between the subassemblies. The upper inductor subassembly includes a tubular housing with inductor windings received therein with an upper electrical connector adjacent an upper end of the housing and a lower electrical connector adjacent a lower end of the housing. The lower firing end subassembly includes a ceramic insulator and a metal housing surrounding at least a portion of the ceramic insulator. The ceramic insulator has an electrical terminal extending from a terminal end and an electrode extending from a firing end. A flexible tube couples the upper inductor subassembly to the lower firing end subassembly and maintains the electrical terminal of the lower firing end subassembly in electrical contact with the lower electrical connector of the upper at a pivot joint.
Abstract:
A spark plug having a center electrode assembly that includes a center electrode and precious metal insert that is both mechanically interlocked and welded to the center electrode in a manner that permits trapped gases to escape from between the two components. Also disclosed is a method for manufacturing the same. During assembly, the precious metal insert is placed into a blind hole that extends axially into a lower end of the center electrode. Once in place, the center electrode is deformed around an enlarged head section of the insert to mechanically interlock the two components together. To further strengthen this attachment, the two components are welded together about their circumference. In one embodiment, the weld includes several interruptions that function as vapor vents for any gases that may be trapped. In other embodiments, a radially or an axially-extending vent hole is used in lieu of the weld interruptions.