GB1266803A - - Google Patents

Abstract

1,266,803. Fuel injection systems. SOC. INDUSTRIELLE DE BREVETS ET D'ETUDES. Feb.6, 1970 [Feb. 14, 1969; April 28, 1969], No.5701/70. Heading G1N. [Also in Division F1] In an I.C. engine fuel injection control system, the quantity of fuel injected is determined by the position of an auxilliarly throttle member 8 positioned in the air intake manifold 1 upstream of the main throttle member 2. A rotary member 5, which may be driven at a constant speed or by the engine, provides a release signal, e.g. by a magnet 24 and sensor 23, for a predetermined constant fraction of rotation, this release signal then causing a generator 6 to provide a signal for energizing the electromagnet(s) 4 of the injection valve(s) 3. As shown, during the release signal a capacitor 19 is charged through a switch 21 by a battery 22, and at the end of the release signal the capacitor is discharged through a resistor varied by the auxilliarly throttle position and a threshold circuit 46 thus energizing the electromagnet 4 as long as the discharge current exceeds the threshold. In another embodiment, Figs. 3-5 (not shown), the release signal energizes a flip-flop (57) to provide an output signal whose duration is determined by comparing the signal on the wiper of a potentiometer positioned by the auxilliary throttle member with the feedback signal of a modulating member (50) actuated by the flip-flop (57). The output signal is then compared in an AND gate (65) with a signal whose duration is representative of that required to provide fuel during idling, thus providing a fuel inhibition facility. In a further embodiment, Figs. 6 and 7 (not shown), the release signal is applied to one input of a flip-flop (103) whose other input is connected to the output of a read-out device (91) and decoding member (93). The read-out device is supplied with the number of counts stored in a read-in device (90) during a previous release signal this number of counts being determined by the position of the auxilliary throttle. The number of counts in (91) is then reduced to zero at a constant frequency, an output signal being provided by the flip-flop 103 during this time. The output pulse may again be compared with the idling value pulse. The energizing pulse duration may be increased during starting and the fuel pressure may be adapted to the pressure between the two throttle members 2, 8 to adapt the fuel-flow to conditions of acceleration.