Abstract: A spark plug having a center electrode and a ground electrode wherein the spark portion of at least one of the center electrode and ground electrode includes a base material and a protective material that substantially prevents corrosion of the base material.

Abstract: A spark plug having a center electrode with a spark portion formed from a sintered powdered metal and a method of manufacture thereof.

Abstract: An ignition and diagnostic system (10) for an internal combustion engine includes a sparking device (12) through which a low voltage diagnostic device (54) monitors a sensing feature, for example spark gap (30) conditions, during spark intervals and returns diagnostic feedback to an engine control module (56). A coil (44) is electrically operatively connected to the sparking device (12) through a lead wire (48). The lead wire (48) can be removed and reinstalled with respect to the sparking device (12) via a flexor joint (60) for installation and maintenance. The flexor joint (60) enables positive electrical contact during operation so that low voltage signals from the diagnostic device (54) are maintained even during severe vibration conditions. The flexor joint (60) includes in one embodiment a compression spring (62) which is fully compressed or over-compressed.

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.

Abstract: An engine cover with integrated ignition system components that provides a protective enclosure for ignition coils in a distributorless ignition system of an internal combustion engine. The cover serves as a cylinder head cover for sealing over the valve assembly of the engine and for that purpose includes a plastic housing having an upper wall and side walls that extend downwardly to a perimeter mounting surface of the housing. The housing includes a unitary compartment that is located above the upper wall. The ignition coils are mounted within the compartment and are electrically connected via terminals to high voltage leads that are embedded in the upper wall and that extend laterally to a corresponding second group of terminals located at the lower surface of the upper wall. These terminals are positioned so as to electrically connect to the engine spark plugs when the cover is installed on the engine.

Abstract: An engine cover with integrated ignition system components that provides a protective enclosure for ignition coils in a distributorless ignition system of an internal combustion engine. The cover serves as a cylinder head cover for sealing over the valve assembly of the engine and for that purpose includes a plastic housing having an upper wall and side walls that extend downwardly to a perimeter mounting surface of the housing. The housing includes a unitary compartment that is located above the upper wall. The ignition coils are mounted within the compartment and are electrically connected via terminals to high voltage leads that are embedded in the upper wall and that extend laterally to a corresponding second group of terminals located at the lower surface of the upper wall. These terminals are positioned so as to electrically connect to the engine spark plugs when the cover is installed on the engine.

Abstract: A spark plug having ground and center electrodes that include a firing tip formed from an alloy containing platinum, tungsten, and yttrium oxide. The firing tip can take the form of a pad, rivet, ball, wire, or other shape and can be welded in place on the electrode. The firing tip provides good erosion resistance, a reduced sparking voltage, good welding and forming characteristics, as well as a minimal occurrence of oxidation of the alloy at the weld area. Desirable ranges of the relative amounts of platinum, tungsten, and yttrium are also disclosed.

Abstract: A spark plug is installed in an internal combustion engine to monitor engine performance. The spark plug includes a core having a central longitudinal axis and defining a first bore extending along the central longitudinal axis. A layer of insulation surrounds the bore. A sensor is located within the bore. A first electrode is embedded in the core remote from the bore. The electrode includes a firing portion at a firing end of the spark plug. A ground electrode is arranged adjacent to the firing portion of the first electrode.

Abstract: A spark plug includes a ground electrode, a firing electrode, an insulator core, and an outer shell surrounding the insulator core. The outer shell has a threaded section for mounting the spark plug in a combustion engine and a splined section for installation of the spark plug. The splined section includes at least one spline having an outer surface and a corresponding castellation recessed from the outer surface.