GB1338283A - Fuel supply system for ic engines - Google Patents

Abstract

1338283 Fluid logic switching circuits; regulating I.C. engine fuel injection BORGWARNER CORP 12 Nov 1971[28 Dec 1970] 52647/71 Heading F1B and F1P A pneumatic fluid logic switching circuit for providing periodic pulses for controlling the fuel valve 21 of an I.C . engine 10 thereby admitting timed injections of fuel through a nozzle 17 comprises a monostable switch 39 having its supply inlet 56 connected by lines 31, 35 to a compressed air source 30 a first control input 57 connected to the output 44 of an air pulse generator 38 mechanically connected at 47 to a camshaft 11 of the engine, a second control (inhibitor) port 58 connected through a capacitor 62 and resistriction 63 to the output 44 and subjected to a bias signal pressure in a line 67 responsive to both engine speed and of induce air flow into manifold 15, a preferred outlet 59 and an alternate outlet 61 which carries a train of intermittent pressure pulses to the valve 21 and having a time duration i.e. pulse width inversely proportional to the bias signal pressure at 58, 67 and a frequency proportional to engine speed. Fuel valve 21 is a monostable fluidic valve powered by a pump 19 drawing from a fuel tank 18 to which the preferred outlet 23 of the valve is connected whilst the alternate outlet 24 is connected to nozzle 17. The bias signal pressure line 67 includes two restrictors and a capacitor 76 and forms the alternate outlet of a monostable switch 41 having a power supply 77, a control input port 81 connected to the air pulse generator outlet 44 and a control input port 82 connected to said outlet 44 and by a bias pressure line 86 to one output 88 of a proportional amplifier 42. The latter has a power supply 87, a control input 91 connected through a restrictor 93 to the power supply line 31 and connected by a line 96, 97 to a Venturi 14 in the air inlet manifold 16, and an opposed control input 92 which may be connected through restrictor 98 to atmosphere by means of a restricted line 102 to line 97. A further output 89 is connected to atmosphere. In operation and with restrictors 98, 99 and lines 101, 102, 103 eliminated so that port 92 is open to atmosphere the relatively small pressure signal in line 86 varies with the rate of change of flow rate to the engine whereas with 98, 99, 101, 102, 103 in circuit a relatively large signal in line 86 varies with the flow rate change. The resulting pulses in line 67 have a frequency dependant on engine speed and a width inversely proportional to air flow.