PURPOSE: To obtain always the most appropriate ignition timing in spite of a condition of ground, on which a car is running, by detecting an absolute pressure in a VC hole of a carburetter for an engine and thereby controlling the ignition timing.
CONSTITUTION: An ignitor circuit portion 200 is constituted with a monolithic integrated circuit (MIC) and an ignition is effected at a time delayed by a poper angle from the first ignition timing determined by an output of a pickup coil 3 during a switch 5 is closed, while an operation of a circuit 201 constituted with a similar MIC is stopped and the ignition is effected at the first ignition timing during the switch 5 is opened. In this case, an ignition timing adjusting circuit is constituted with a triangular wave producing circuit consisting of resistors 34W36, NPN transistors 75W77, PNP transistor 86, 87, diodes 100W102 and a capacitor 53, and a charging current for the capacitor 53 is varied in accordance with an output of an absolute pressure sensor 606 detecting an absolute pressure in a VC hole of a carburetter.
SUGIURA NOBORU
YOSHINARI TAKASHI
| JPS5344613A | 1978-04-21 |
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