GB1371946A - Device for regulating the amount of fuel injected by injection systems of internal combustion engines - Google Patents

Abstract

1371946 I C engines - fuel control ALFA ROMEO SpA 24 Feb 1972 [24 Feb 1971] 8706/72 Heading F1B [Also in Division G1] The invention relates to an arrangement for regulating the amount of injected fuel for injection systems of I.C. engines. The system comprises a three-dimensional cam 1 and a follower 4, the cam being mounted on a shaft 2 which is movable axially in dependence on engine speed and rotationally in dependence on angular position of the throttles 61, 62, 63, 64, the axial position of the cam follower 4 being sensed by a mechanical/electrical transducer 7 the electric signal from which is passed through a processor 77 which transmits signals to the windings 38, 39, 40, 41 of the fuel injection devices 34, 35, 36, 37, The system comprises a mechanical/electrical transducer 82 connected to the engine shaft, the electrical output signal 84 being passed to a comparison means 85 from which an error signal 87 passes through distribution means 88 from which a signal passes either through line 89 or line 90 to an electrical/mechanical transducer 91, the mechanical output signal 92 from which is amplified at 93, the mechanical signal 72 being transmitted to the device 71 which is the three-dimensional cam and follower 1, 4, the speed signal 72 acting to produce axial movement of the shaft 2 and cam 1. The mechanical signal 73 is the signal representing angular position of the throttle members 61, 62, 63, 64 and is communicated through gearing 11, 10 to produce angular movement of the shaft 2 and cam 1. The resulting axial position of the cam follower 4 is sensed by the mechanical/electrical transducer 75 in the form of a potentiometer 7 and the signal 76 is transmitted through the processor 77 to the windings of the fuel injectors 34, 35, 36, 37. Axial movement of the shaft 2 and cam 1 is produced by means of a link 14 pivotally mounted at 15 and bearing at 13 against the end of the shaft 2. The diaphragm 19 of a pressure capsule 21 is connected through pin 17 to a point 17 on the link, and the diaphragm 18 of a pressure capsule 21 is connected through pin 16 to a point 16' on the rod. The pressure capsule 21 is open either through valve 42 or valve 47 to pressure in line 23 or to pressure in line 48 depending on whether current is flowing to coil 49 or coil 50, i.e. whether current is passing through line 89 or line 90, Fig. 1. The pressure capsule 20 is always connected through line 22 to pressure in line 24 and acts as a constant biasing force. The angular position of the shaft 2 and cam 1 may alter- natively be dependent on suction pressure in the intake manifold.