| 摘要 |
PURPOSE:To prevent the irregular combustion during idling, by providing a circuit wherein when the opening of the throttle is not greater than a predetermined opening and the rotational frequency is not greater than a predetermined rotational frequency, the ignition timing is delayed, on the other hand, when they are greater than the predetermined opening and rotational frequency, the ignition is not effected. CONSTITUTION:To a contact 9a of a change-over switch 8 will be connected a normal ignition timing trigger 10, and to a contact 9b will be connected a delay angle ignition trigger 11 so that when the throttle becomes in a predetermined opening state, the contact 9b of the change-over switch 8 correlated therewith can be closed. When the opening of the throttle is not greater than the predetermined opening and the rotational frequency is not greater than a predetermined rotational frequency, by the voltage of the trigger coil 11 a thyristor 6 for ignition becomes conductive to ignite at a delay angle point, on the other hand, if it becomes greater than the predetermined rotational frequency, a by-pass thyristor 16 becomes conductive, and the voltage generated in an electricity generating coil 1 is earthed not to ignite. Consequently, abnormal combustion such as knocking or the like can be prevented and therefore damage to the engine can be prevented. |
