Programmed electronic advance for engines

摘要

The spark plug ignition advance control for a multiple cylinder internal combustion engine has a spark ignition circuit associated with each cylinder. The circuit includes an SCR trigger operative to cause the ignition spark. A pulse generator is associated with each cylinder and puts out a control pulse to a latch gate outputing to the ignition circuit. The gate responds to a control pulse to latch in an enabled state. A frequency multiplier receives control pulses from the pulse generator and provides 360 reference pulses for each revolution of the engine. A counter responds to the control pulse to count said reference pulses. A ROM storing ignition timing data corresponding to throttle position. A throttle position sensor provides a control voltage which is applied to an A/D converter which outputs an address in the ROM and the ROM puts out the number of degrees by which the base throttle advance is to be modified and sets the counter to count said reference pulses to said number. The counter subtracts the counts (degrees) from the basic (maximum) advance and outputs a control signal (firing pulse) when the correct advance is reached. The firing pulse is applied to the latch gate which causes the SCR trigger to operate. The firing pulse also resets the system to start again for the next cylinder.