System for controlling the ignition and injection of internal combustion engines

Claim 1

An ignition and injection control system for use in conjunction with an internal combustion engine comprising a crankshaft wiper having a series of identical alternating sectors and notches, each of said sectors and notches having an angle in the center having a common divisor with the successive angles made by the pistons between their respective dead centers during a complete engine operating cycle, said wiper being mounted for rotation with the crankshaft; first proximity detector means stationarily mounted near the crankshaft wiper and comprising at least one sensor for producing at least one series of signals each of which terminates at a dead center of a piston; a timing wiper carried by the engine camshaft and rotating at half the speed of the crankshaft, said timing wiper having alternating sectors and notches the number of which is equal to no more tHan the number of cylinders in the engine and the arrangement of which corresponds to the angular offset of the cycles specific to each cylinder of the engine; second proximity detector means having a sensor stationarily mounted near said timing wiper and forming, with the end of each sector corresponding to the dead center of a piston, a lead angle whose value is equal to at least half the absolute value of the error angle which can exist between the crankshaft and the camshaft for producing successive signals in advance with respect to the considered dead center of each piston but with unprecise leading and trailing edges; and logic circuit comparison means connected to said first and second proximity detector means for producing a resultant signal, in advance with respect to the said dead center of each piston, whenever a correspondence exists between signals produced by said first and second proximity detector means, so that the imprecision of the signal coming from the timing wiper is corrected by the signals coming from the crankshaft wiper.