Electronic fuel injection system

Claim 1

In an interval combustion engine system including a group of eight fuel injection units for applying fuel to the engine when energized in a given injection order during each engine cycle, the combination comprising: means responsive to the operation of the engine for generating a set of four first order timing signals A1, A2, A3 and A4, each having alternate level transitions spaced at intervals of one-half engine cycle within each of the timing signals A1-A4 and displaced at intervals of one-eighth engine cycle between each of the timing signals A1-A4; means responsive to the set of first order timing signals A1-A4 for producing a first set of four second order timing signals B1, B2, B3 and B4 given by the following logical equations: B1 A1 . A3 B2 A2 . A4 B3 A1 . A3 B4 A2 . A4; means responsive to the first set of second order timing signals B1-B4 for producing a second set of two second order timing signals C1 and C2 given by the following logical equations: C1 B1 + B3 C2 B2 + B4; means responsive to the second set of second order timing signals C1 and C2 for producing a third set of four second order timing signals D1, D2, D3 and D4 given by the following logical equations: D1 C1 . C2 D2 C1 . C2 D3 C1 . C2 D4 C1 . C2; means responsive to the third set of second order timing signals D1-D4 for producing a single third order timing signal E given by one of the following logical equations: E D1 + D3 E D2 + D4; means responsive to the third order timing signal E for producing a single third order pulse train F containing control pulses initiated at intervals of one-eighth engine cycle in response to each level transition in the timing signal E, the means connected to the engine for defining the duration of the control pulses In the pulse train F as a function of at least one engine operating parameter up to a maximum of approximately oneeighth engine cycle; means responsive to the third order pulse train F and to the third set of second order timing signals D1-D4 for producing a set of four second order pulse trains G1, G2, G3 and G4 given by the following logical equations: G1 F . D1 G2 F . D2 G3 F . D3 G4 F . D4; means responsive to the set of second order pulse trains G1-G4 for extending the duration of the control pulses within the pulse trains G1-G4 by a maximum factor of four (4) to provide a set of four second order trains G1'', G2'', G3'' and G4'' containing control pulses having a maximum duration of approximately one-half engine cycle; means responsive to the set of second order pulse trains G1''-G4'' and the set of first order timing signals A1-A4 for producing a series of eight first order pulse trains H1, H2, H3, H4, H5, H6, H7 and H8 given by the following logical equations: H1 G1'' . A1 H2 G2'' . A2 H3 G3'' . A3 H4 G4'' . A4 H5 G1'' . A1 H6 G2'' . A2 H7 G3'' . A3 H8 G4'' . A4; and means for applying the series of first order pulse trains H1-H8 to corresponding ones of the group of fuel injection units to energize the fuel injection units for the duration of the control pulses in the pulse trains H1-H8.