Spark plug

• Main Authors: KAZUKI ITO, SHIBATA TSUTOMU, SUMOYAMA DAISUKE
• Format: Patent
• Language: Chinese; English
• Published: 25.01.2019
• 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

The present invention provides a spark plug capable of improving the durability of a ground electrode. The spark plug includes: a main body metal case having a through hole extending in a direction ofthe axis; an insulator fixed to an inner peripheral side of the main body metal case; a center electrode including a portion disposed at a tip end portion of the insulator and forming the first discharge surface; and a rod-shaped ground electrode having a base end joined to an annular top end surface of the main body metal case, and forming a second discharge surface at the distal end portion, wherein a discharge gap is formed between the second discharge surface and the first discharge surface of a central electrode. A cross section in the vicinity of the base end of the ground electrode, that is, an outline of a cross section perpendicular to the axis, includes a first side indicating an outer surface on the inner circumference side, a second side connected to one end of the first side,and a third side connecte