Abstract: The present invention relates to a process for manufacturing an ignition device or connector for an internal combustion engine and the ignition device or convection obtained by such process. The ignition convector, in use, creates a plasma for igniting lean mixtures. Said device an insulator 2 containing a central electrode 3 and a metal shell 4, in which the insulator is fixed. The ground electrode of conventional spark-plugs is replaced by a circular capsule 17 welded to the shell base, after having been subjected to a hard chromizing treatment. The shell comprises an annular recess 14 provided in the thickness of its wall, and is welded to the ceramic insulator 2 by brazing.

Abstract: A plier (35, 36) of which the jaws are provided with claws (38, 39) of electrically good conductor metal, threaded in a complementary way to that of the threaded portion (10) of the cap (4) of the device (1), grips the device (1) by that threaded portion (10) of the cap (4) while strongly pressing the capsule (17) on the threaded end (10) of the cap (4) and heating those parts by Joule effect. The plier rests on a portion (26) which rests itself on the frame (25) of the machine. Hence, the insulating portion of ceramic material (2) of the device is not subjected to any stress due to the pressure exerted during such welding operation.