Fuel oil injection engine

摘要

The circulatory fuel oil injection supply system of a diesel engine is adapted so that the engine may be run selectively either in a single fuel mode on diesel oil alone or in a dual-fuel mode on both diesel oil and gas. The control system and fuel system of the engine are modified so that pressure conditions at a diesel oil injection metering device during the single-fuel mode are mimicked by a first flow restrictor during the dual-fuel mode. A pressure sensor measures the mimicked pressure and controls the amount of gas flow to the engine via an electronic programmable control. A shut-off first solenoid valve operative in the single-fuel mode circuit is by-passed in the dual-fuel mode while second and third solenoid valves are operative to open a by-pass line including a second flow-restrictor and to open a reference pressure supply line respectively. A governor control and a throttle control having a by-pass weep line remain operative in both the single-fuel mode and in the dual-fuel mode. In a further modification the first flow-restrictor and third solenoid valve and the second flow-restrictor and the second solenoid valve are replaced by respective pulsed solenoid valves providing variable flow-restrictors so as to allow a variable amount of pilot diesel fuel oil to be supplied in the dual-fuel mode via the electronic control.