Electronic fuel injection control system

Claim 1

An electronic fuel injection control system for an engine, the engine having a fuel injection valve and a synchronizing signal generator to generate an electric synchronizing signal, said control system comprising; a first sensor to sense a primary operating parameter of the engine and generate an electric primary analog signal analogous thereto; a second sensor to sense at least one secondary operating parameter of the engine and generate an electric secondary analog signal analogous thereto; a primary pulse generator responsive to said primary analog signal to generate an electric primary pulse signal having a pulse width analogous thereto; a secondary pulse generator responsive to said secondary analog signal to generate an electric secondary pulse signal having a pulse width analogous thereto; a pulse train generator responsive to said primary and secondary pulse signals being operative to alternately generate primary and secondary pulse train signals respectively, said primary pulse train signal having a first number of pulses which is a first predetermined function of the pulse width of said primary pulse signal, and said secondary pulse train signal having a second number of pulses which is a second predetermined function of the pulse width of said secondary pulse signal; a variable clock pulse generator responsive to said secondary pulse train signal to generate clock pulses at a frequency which is a third predetermined function of said second number of pulses; a counter responsive to the synchronizing signal, said primary pulse train signal, and said clock pulses, being operative to count said first number of pulses at the frequency of said clock pulses, the counting operation commencing when said synchronizing signal is received; and an injection pulse generator connected to said counter and operative to generate an injection pulse signal to open the fuel injection valve for the duration of the counting operation of said counter.