GB1319671A - Fuel injection systems - Google Patents

Abstract

1319671 Fuel injection systems JOSEPH LUCAS (INDUSTRIES) Ltd 2 Sept 1971 [7 Sept 1970] 42813/70 Addition to 1272595 Heading G1N In an I.C. engine fuel injection control system as claimed in Specification no 1272595, the further injection valve energizing pulses produced when acceleration of the engine is required are provided at a constant frequency. As shown, the further pulses are supplied by a constant frequency pulse generator 28 via an AND gate 32 which is enabled when the rate of change of a signal V(p) representing manifold pressure exceeds a threshold in comparator 38. The devices 40, 38 and 32 may be replaced by the switches shown in Figs.2 and 3 (not shown) of the parent Specification. A signal V(j) representing the throttle position may be utilized in place of V(p) The generator may be replaced by a constant frequency ramp generator and a comparator which receives its inputs from the ramp generator and the output of the differentiator 40, Fig. 2 (not shown). In an alternative signal representing manifold pressure or throttle position at successive time intervals are compared in a third successive time interval. A predetermined difference causes the AND gate 32 to be enabled, Fig.3 (not shown). The duration of the further pulses may be controlled by the engine and ambient temperatures, or the inlet manifold pressure, and the duration of the main opening pulses may be lengthened when acceleration is required.