| 摘要 |
PURPOSE:To prevent knocking by igniting an auxiliary ignition plug, located in a position where mixture tends to be left unburnt by a main ignition plug, after a specified period delayed from the ignition timing thereof for a normal flame propagation. CONSTITUTION:A main ignition plug 1 is provided in a position deviated toward one side of a combustion chamber 2 and an auxiliary ignition plug 3 in a position deviated to the opposite side to the main ignition plug 1 in the combustion chamber 2. The main ignition plug 1 is ignited and discharged in a usual ignition timing determined by an angle advancing unit attached to a contact breaker 6. Thereafter, the auxiliary ignition plug 3 is ignited and discharged in a period delayed by 20 deg.-60 deg. of crank angle. Thus, before unburnt mixture near the auxiliary ignition plug 3 reaches self-firing, it is burnt as a normal flame propagation so that knocking can be remarkably reduced. |
