| 摘要 |
A spark plug comprising: an insulator having a shaft hole; a central electrode which is inserted into the distal end side of the shaft hole; a terminal electrode which is inserted into the rear end side of the shaft hole; and inter-electrode disposed bodies which contain glass and conductive carbon, and are disposed inside the shaft hole and between the central electrode and the terminal electrode. The resistance value of the inter-electrode disposed bodies is 1.0-3.0 k&OHgr; inclusive. At a distal end side site among the inter-electrode disposed bodies, said distal end side site being positioned further towards the distal end side than the centre point between the central electrode rear end and the terminal electrode distal end, the carbon content is 1.5-4.0 mass% inclusive. Moreover, the resistance value of the distal end side site is set so as to be less than the resistance value of a rear end side site among the inter-electrode disposed bodies, said rear end side site being positioned further towards the rear end side than the centre point. |
