GB1315974A - Combustion engine fuel injection apparatus having fluidic control means - Google Patents

Abstract

1315974 Fluid logic and switching circuits; spray carburetters BENDIX CORP 8 July 1970 [9 July 1969] 33212/70 Headings FIB and F1P Each of a plurality of cylinders of a conventional I. C. engine has its individual air inlet pipe 22 and exhaust pipe 32 connected to an individual fluidic apparatus 34 for controlling the supply of fuel to a nozzle 38 in air inlet 22 independently of the remaining cylinders and comprising a fuel powered proportional amplifier 136 having an outlet 142 connected to nozzle 38 for supplying fuel thereto in response to air pressure signals supplied to a control port 144 and generated by an amplifier set 88, 104, 120 and which vary with the temperature of the exhaust and inlet. An opposing control port 152 of amplifier 136 is supplied with a reference desired exhaust gas temperature air signal through a line 74 and a branch line 82 of a passage 182 subjected to atmospheric pressure and vacuum at opposite ends, and containing fixed restrictions 184,186 and a by-pass valve 192 mechanically linked to a throttle valve (28) Fig.1 (not shown) in the main air inlet manifold (26). The desired exhaust gas temperature giving rise to the control air pressure at 152 is obtained when valve 192 is closed in response to throttle valve (28) being in engine idle or maximum power position and when desired temperature equals the actual exhaust gas temperature the air pressures at 144, 152 are equal and the fuel input at 138 is divided equally between output 142 to nozzle 38 and to output 140 leading to a return reservoir. In the event of an excess actual exhaust temperature the air-pressure signal at 144 increases resulting in more fuel being directed to nozzle 38, and with a constant cylinder air flow a richer mixture and a corresponding reduction in cylinder exhaust gas temperature. Line 74 and hence control port 152 is also connected to the output 158 of a further manifold air-pressure sensitive fluidic device 66 whereby a sudden opening of throttle valve (28) giving rise to a sudden increase in manifold pressure biases the output of 66 away from 158 and so.reduces the pressure in 74 which results in increased fuel flow to nozzle 38. The air pressure pulses supplied to control port 144 of amplifier 136 and which are responsive to the actual exhaust gas temperature are derived from the output 126, 146 of a mono-stable amplifier 120 having opposed control inlets 128,130 connected respectively through a line 134 at ambient air temperature and a line 132 having a portion thereof subjected to exhaust gas temperature to outputs 110,108 of a bistable amplifier 104 slaved to an oscillator amplifier 88. The latter is exposed to ambient air and the outputs 92, 94 have feedback passages to control input ports 100,102 thus producing alternate pressurization in lines 116,118 leading to control inputs 112,114 of amplifier 104 which in turn produces alternate pressurization of output passages 108,110.