Spark ignition device for an internal combustion engine and central electrode assembly therefore

A spark ignition device, comprising:

• a tubular ceramic insulator extending along a central axis;
• a metal shell surrounding at least a portion of said ceramic insulator;
• a ground electrode operatively attached to said shell, said ground electrode having a ground electrode sparking tip;
• a central sparking tip, said central sparking tip and said ground electrode sparking tip providing a spark gap;
• a first terminal extending coaxially along said central axis and arranged in electrical communication with said central sparking tip and configured for electrical connection with a power source;
• a second terminal spaced radially outwardly from said first terminal and arranged in electrical communication with said first terminal and configured for electrical connection with the power source;
• and
• a heater element spaced radially outwardly from said first terminal and bringing said first terminal in electrical communication with said second terminal and completing an electrical circuit between said first and second terminals, said heater element having a resistance greater than said first and second terminals;
• a central electrode separate from said first terminal and said second terminal, said central electrode having an elongate body extending along said central axis to a free end,
• said heater element being configured as an annular ring extending about said central axis and disposed between said free end of said central electrode and said central sparking tip;
• said first terminal extending substantially through said central electrode along said central axis and being adjacent said central sparking tip;
• and
• said heater element extending between opposite ends with said first terminal being attached to one of said ends.