Abstract: A spark plug having a particular firing end configuration that satisfies numerous dimensional ranges for improved performance. The spark plug generally includes a shell, an insulator, and center and ground electrodes, with the electrodes each having a copper core for improved thermal conductivity and a noble metal insert for improved erosion and corrosion resistance. The noble metal insert for the center electrode is preferably in the form of a cylindrical Ir-based tip, which is received within a complimentary recess formed in the center electrode. The noble metal insert for the ground electrode is in the form of a flat Pt-based pad attached to a surface of the ground electrode. Various dimensional ranges are provided for the various components of the spark plug assembly, both individually and in combination with other dimensions.

Abstract: A spark plug having a particular firing end configuration that satisfies numerous dimensional ranges for improved performance. The spark plug generally includes a shell, an insulator, and center and ground electrodes, with the electrodes each having a copper core for improved thermal conductivity and a noble metal insert for improved erosion and corrosion resistance. The noble metal insert for the center electrode is preferably in the form of a cylindrical Ir-based tip, which is received within a complimentary recess formed in the center electrode. The noble metal insert for the ground electrode is in the form of a flat Pt-based pad attached to a surface of the ground electrode. Various dimensional ranges are provided for the various components of the spark plug assembly, both individually and in combination with other dimensions.

Abstract: A spark plug having a particular firing end configuration that satisfies numerous dimensional ranges for improved performance. The spark plug generally includes a shell, an insulator, and center and ground electrodes, with the electrodes each having a copper core for improved thermal conductivity and a noble metal insert for improved erosion and corrosion resistance. The noble metal insert for the center electrode is preferably in the form of a cylindrical Ir-based tip, which is received within a complimentary recess formed in the center electrode. The noble metal insert for the ground electrode is in the form of a flat Pt-based pad attached to a surface of the ground electrode. Various dimensional ranges are provided for the various components of the spark plug assembly, both individually and in combination with other dimensions.

Abstract: An ignition device such as a spark plug having ground and center electrodes, at least one of which includes a firing tip formed from an alloy containing iridium, rhodium, tungsten, and zirconium. With the inclusion of tungsten and zirconium in the alloy, the percentage of rhodium can be kept relatively low without sacrificing the erosion resistance or reduced sparking voltage of the firing tip. In one embodiment, the firing tip contains 2% rhodium, 0.3% tungsten, 0.02% zirconium, and the balance iridium.

Abstract: A noble metal tip 20 for attachment to a spark plug center electrode 36 and/or a ground electrode. Noble metal tip 20 is a generally cylindrical component that includes a firing end 40, an attachment end 42, and one or more retention features 44, 46 and 60, 62. The retention features are generally conically shaped holes or recesses formed in the side of the noble metal tip, and are designed to receive molten material during a laser attachment process. Once the molten material has solidified in the retention features, a fusion layer is formed and acts as a mechanical bond or interlock between the noble metal tip and the electrode. Methods of manufacturing and attaching the noble metal tips are also provided.

Abstract: A spark plug having a particular firing end configuration that satisfies numerous dimensional ranges for improved performance. The spark plug generally includes a shell, an insulator, and center and ground electrodes, with the electrodes each having a copper core for improved thermal conductivity and a noble metal insert for improved erosion and corrosion resistance. The noble metal insert for the center electrode is preferably in the form of a cylindrical Ir-based tip, which is received within a complimentary recess formed in the center electrode. The noble metal insert for the ground electrode is in the form of a flat Pt-based pad attached to a surface of the ground electrode. Various dimensional ranges are provided for the various components of the spark plug assembly, both individually and in combination with other dimensions.

Abstract: A spark plug having a particular firing end configuration that satisfies numerous dimensional ranges for improved performance. The spark plug generally includes a shell, an insulator, and center and ground electrodes, with the electrodes each having a copper core for improved thermal conductivity and a noble metal insert for improved erosion and corrosion resistance. The noble metal insert for the center electrode is preferably in the form of a cylindrical Ir-based tip, which is received within a complimentary recess formed in the center electrode. The noble metal insert for the ground electrode is in the form of a flat Pt-based pad attached to a surface of the ground electrode. Various dimensional ranges are provided for the various components of the spark plug assembly, both individually and in combination with other dimensions.

Abstract: A fuel injector (10; 100) comprises an inlet (60) from which fuel can be transferred into a cavity (61) of the injector, at least one outlet orifice (86) communicating with said cavity (61), and ejecting means (44, 88) operable to apply force to fuel in said cavity to cause said fuel to be ejected through said orifice as discreet charges at pre-determined intervals. The operation of said ejecting means (44, 88) is also operable to transfer further fuel into said cavity (61).