IC engine ignition timing control circuit - uses signal of duration corresponding to passage of known sector of shaft past datum mark as timing indication

摘要

The system is for the periodic analogue control of one or more functions dependent on one or more parameters and particularly the speed of a shaft, regulating the passage of datum mark on the shaft past a fixed one, e.g. in an engine ignition timing system. A signal is generated, whose duration corresponds to the passage of a rotary sector of a known angle past a fixed datum mark. During the absence of this signal a complementary signal P1 is generated. After generation of signal P two voltages of specified formular are generated. A control signal is generated when a second voltage becomes equal to the corresponding first one. This control signal is used to control ignition timing.