SPARK PLUG FOR INTERNAL COMBUSTION ENGINE

• Main Authors: NAKAMURA SHINICHI, MATSUMURA SHUZO
• Format: Patent
• Language: English
• Published: 07.05.1993
• Subjects: BASIC ELECTRIC ELEMENTS; CORONA DEVICES; ELECTRICITY; GENERATING IONS TO BE INTRODUCED INTO NON-ENCLOSED GASES; OVERVOLTAGE ARRESTERS USING SPARK GAPS; SPARK GAPS; SPARKING PLUGS

PURPOSE:To improve sparking property by thinning a center electrode to correspond to the tip part of a ground electrode and at the same time installing a plate- or rod-like igniting electrode made of a noble metal or a noble metal alloy in the surroundings of the thin part. CONSTITUTION:Corresponding to the flat tip part 13 of one or a plurality of ground electrodes 10 to be joined with the tip of a screw 9 of a main metal fitting, the tip part of a center electrode 4 to be held by an insulator 2 is thinned. In the surroundings of the thin part 16 of the center electrode 4, a circular or square plate-or columnar or prismatic rod-like igniting electrode 15 made of a noble metal or a noble metal alloy is installed. Consequently, even if the igniting electrode 15 is consumed, the effective surface area of the igniting electrode 15 is its cross section surface area and always constant, so that sparking property is effectively improved even for the thinned center electrode 4.