Ignition timing control system for internal combustion engine

摘要

An acceleration sensor senses mechanical noise components and a knock signal originating from an internal combination engine. The knock signal is separated from the attenuated noise components and compared with a DC voltage due to the latter to form pulses. The pulses integrated by an integrator are applied to a phase shifter to retard an ignition time. During the acceleration of the engine, a switch is opened in response to a pressure in an intake manifold in excess of a predetermined magnitude to cause an acceleration compensation circuit to decrease the charging time constant of the integrator resulting in an increase in retard of the ignition time point.