Patent GB-1024774-A (GB)
Title: Improvements in and relating to fuel-injection control systems for engines
IPC: F02D41/30
Filed: 1963-06-19
Abstract: 1,024,774. Electric correspondence control systems. NOVI-P.B.S.A. June 19, 1963 [June 20, 1962], No. 24323/63. Heading G1N. [Also in Division F1]. In an I. C. engine fuel injection system having an electromagnetically controlled injector, the magnitude of energization is varied to control the stroke of an armature thereby determining the amount of fuel injected. In one embodiment an engine-driven twopole alternator 1, Fig. 3 (not shown) is connected in series with a diode 4 and an injector control electro-magnet 2, regulation being affected by a rheostat 3a controlled by the throttle position. In another embodiment the winding 1, Fig. 4 (not shown) of an engine-driven four pole magnetic flywheel supplies four pulses per cycle and if the circuit includes a diode as in Figs. 3 and 2 (not shown) two impulses per cycle are passed, one impulse being used for ignition through lead 5, the other energizing the electromagnet 2 through transistor 6. A pulse generator 7 connected to the base of transistor 6, is regulated by a throttle-linked rheostat 3 or by an altitude-connecting capsule 9 linked to rheostat 8. Speed regulation is effected by an engine driven voltage generator 10 which charges capacitor 13 through a regulating rheostat 11 and diode 12 to operate by changing the polarity of the base of transistor 6. The pulse generator may be replaced by a double control diode, tunnel diode or single junction transistor. In the embodiment of Fig. 5, a coil 14 applies approximately 300 volts across a rectifier bridge 15 to charge capacitor 16 through resistor 17, the capacitor 16 discharging through controlled diode 18 to injector electromagnet 2 when an impulse is emitted by pulse generator 7. A resistor 19 and capacitor 20 shunted across diode 18 enable the diode to be blocked when the impulse ceases. For speed regulation, when the voltage of coil 14 rises, Zener diode 22 is energized at a value controlled by resistor 23 and current is passed to energize an electrically controlled fuel feed valve 21 to cut off fuel feed. In another embodiment the effect of a vehicle lighting circuit is eliminated by means of a change over switch which places a resistor, having an equivalent impedance in the circuit. Regulation of the injector electromagnet in dependence on throttle position, air pressure or engine speed is effected by movement of plunger cones in inductance coils. In a modification speed limitation may be effected by a circuit including a Zener diode acting on a pulse generator. In a further embodiment a diode in the circuit of the injector electromagnet is separately blocked or operated by separate pulse generators. Alternatively the operating pulse generator is replaced by a tapping from the low-tension supply coil. Current regulation is by means of a saturable inductance coil in which variation of inductance is caused by passage of a direct current which is varied by capacitors linked respectively to an altitude capsule and to the throttle control and by a diode-rectified voltage generator which restricts the engine speed.