ELECTRONIC FUEL INJECTION SYSTEM

摘要

An internal combustion engine includes a group of eight fuel injectors for applying fuel to the engine. A set of four first order timing signals are developed in synchronization with engine operation. The set of first order timing signals collectively contain eight magnitude permutations per engine cycle each defining the start of injection for a corresponding one of the fuel injectors. The set of four first order timing signals is mixed to form a first set of four second order timing signals, which is mixed to form a second set of two second order timing signals, which is mixed to form a third set of four second order timing signals, which is mixed to form a single third order timing signal containing all eight magnitude permutations per engine cycle. A single third order pulse train is developed in synchronization with the single third order timing signal. The single third order pulse train contains eight control pulses per engine cycle each initiated in response to one of the eight magnitude permutations per engine cycle in the single third order timing signal. The length of each control pulse defines the period of injection for a corresponding one of the fuel injectors in time compressed nonoverlapping relationship. The single third order pulse train is separated in response to the third set of second order timing signals to form a set of four second order pulse trains collectively containing all eight control pulses per engine cycle. The length of each control pulse in the set of second order pulse trains is extended to define the period of injection for a corresponding one of the fuel injectors in time expanded overlapping relationship. The set of second order pulse trains is separated in response to the set of first order timing signals to form a series of eight first order pulse trains each containing control pulses which are applied to energize a corresponding one of the group of eight fuel injectors.