Pre-ignition controller for turbo charged IC engines - uses pressure transducer to detect pre-ignition and open valve feeding exhaust gas back into the fuel and air mixture

摘要

The arrangement uses a pressure transducer (15) in the inlet manifold (3) to indicate pre-ignition in a supercharged (5,6) engine. If pre-ignition is detected a valve (14) opens to allow the exhaust gases (7) to mix with the incoming fuel/air mixture, diluting the mixture and reducing the cylinder temp. at combustion. The pressure transducer comprises a capsule with a membrane cooperating with a valve forming the exhaust gas injector. The injection of the exhaust gas is provided by the naturally occurring pressure difference between the exhaust and the engine intake. The detection of pre-ignition is provided by a circuit which produces a variable voltage which amplified and pass-band filtered. The voltage is then applied to a threshold detector which, under excess voltage, actuates a solenoid valve. The valve may be opened as a function the applied voltage.