Hydraulic powered fuel injection with oil viscosity detector e.g. for diesel IC engine

摘要

The injectors (2) of the IC engine have pistons which are displaced by hydraulic pressure from a pressure manifold (20) to pressurise the fuel prior to injecting into the cylinders. Each injector has a solenoid valve to connect the hydraulic pressure to the piston and the whole system is controlled by an ECU (18). The system has the facility to measure the viscosity of the oil and the ECU makes appropriate correction for changes in viscosity. The injectors are linked by a hydraulic manifold (20) changed by a separate hydraulic pump (9) which draws oil from the engine sump. The viscosity is measured by measuring the output pressure (56) of the engine lubrication pump (54) which is driven off the engine, making due allowance for engine speed. The injector solenoids are activated for as long as required to inject the required amounts of fuel. The fuel pressure lifts the needle valve of each injector to spray fuel into the cylinder.