Spark ignition device and ground electrode therefor and methods of construction thereof

A method of constructing a spark ignition device, comprising:

• providing a generally annular insulator;
• disposing a center electrode at least in part in the insulator;
• disposing a metal shell around at least a portion of the insulator, the metal shell including a distal end presenting a planar surface and a protrusion extending axially outwardly from the planar surface;
• before or after the step of disposing the metal shell around at least a portion of the insulator, capacitive pulse discharge welding an attachment end of a ground electrode to the metal shell, the capacitive pulse discharge welding step including sinking the ground electrode into the protrusion of the metal shell until the attachment end of the ground electrode is flush with the planar surface of the metal shell;
• and
• laser welding the attachment end of the ground electrode to the metal shell.

A method of constructing a metal shell for a spark ignition device, comprising:

• providing an annular metal shell extending between a proximal end and a distal end, the metal shell including a distal end presenting a planar surface and a protrusion extending axially outwardly from the planar surface;
• providing a ground electrode having an attachment end and a firing end;
• capacitive pulse discharge welding the attachment end of the ground electrode to the distal end of the shell, the capacitive pulse discharge welding step including sinking the ground electrode into the protrusion of the metal shell until the attachment end of the ground electrode is flush with the planar surface of the metal shell;
• and
• laser welding the attachment end of the ground electrode to the distal end of the shell.