초록 ▼

A gas-diesel dual fuel engine operative with both a gaseous fuel and a diesel fuel oil. The engine has an electronic governor circuit adapted to receive both a speed signal representing actual speed of engine and a set speed signal representing a predetermined command speed of the engine, electric a

A gas-diesel dual fuel engine operative with both a gaseous fuel and a diesel fuel oil. The engine has an electronic governor circuit adapted to receive both a speed signal representing actual speed of engine and a set speed signal representing a predetermined command speed of the engine, electric actuators adapted to actuate a diesel fuel injection pump and a gaseous fuel regulating valve, respectively, in response to the signal from the electronic governor circuit, and a mode switching control circuit connected to the electronic governor circuit and adapted to switch the operation of the electric actuators between a diesel fuel operation mode and a gaseous fuel operation mode.

대표청구항 ▼

In a gas-diesel dual fuel engine apparatus having a diesel engine, a diesel fuel supply system including a diesel fuel injection pump, a gaseous fuel supply system including a gaseous fuel regulating valve, and a governing and controlling device for governing the speed of said engine through the con

In a gas-diesel dual fuel engine apparatus having a diesel engine, a diesel fuel supply system including a diesel fuel injection pump, a gaseous fuel supply system including a gaseous fuel regulating valve, and a governing and controlling device for governing the speed of said engine through the control of fuel supplied to said engine and controlling the switchover of the operation of said engine between a diesel fuel mode and a gaseous fuel mode; the improvement that said governing and controlling device comprises: (a) at least one electronic governor means adapted to compare a speed signal representing the actual operating speed of said diesel engine with a set speed signal representing the set speed thereof and to perform a proportional plus integral plus differential operation on the basis of the difference therebetween for outputting a control signal according to the difference between said two speed signals; (b) a pair of electric actuator means having respective power amplifier circuits and mechanically connected to said diesel fuel injection pump and said gaseous fuel regulating valve, respectively, for the actuation thereof; (c) mode switching control means for controlling the switchover of said governing and controlling device between the engine\s diesel fuel operation mode and gaseous fuel operation mode, said mode switching control means being adapted to generate command signals for fully closing said gaseous fuel regulating valve when the engine is in the diesel fuel operation mode and for operating said diesel fuel injection pump to feed said diesel engine with a predetermined amount of a diesel fuel as pilot injection fuel when the engine is in the gaseous fuel operation mode; and (d) signal selecting means connecting said electronic governor means and said mode switching control means to said pair of electric actuator means for selectively delivering said control signal and said command signals, said signal selecting means being controlled by said mode switching control means so that when the engine is in the diesel fuel operation mode, said control signal is delivered to said electric actuator means connected with said diesel fuel injection pump to operate said pump and a command signal is delivered to said electric actuator means connected with said gaseous fuel regulating valve to close said valve, while when the engine is in the gaseous fuel operation mode, said control signal is delivered to said electric actuator means connected with said gaseous fuel regulating valve and a command signal is delivered to said electric actuator means connected with said diesel fuel injection pump to operate said pump for the pilot injection; (e) said mode switching control means comprising a main control circuit, a voltage generating circuit adapted to receive an instructional signal from said main control circuit to generate any desired voltage for said command signals, and a mode switching circuit connected to said voltage generating circuit and said main control circuit and serving as said signal selecting means, said electronic governor means including a PID control circuit adapted to generate said control signal according to the difference between said speed signal and said set speed signal, said pair of power amplifier circuits being connected to receive the control signal from said PID control circuit through said mode switching circuit, one of said power amplifier circuits being operable in response to an input from said mode switching circuit to produce an output for driving said electric actuator means for said fuel injection pump, and the other power amplifier circuit being operable in response to a different input from said mode switching circuit to produce an output for driving said electric actuator means for said gaseous fuel regulating valve, said mode switching control means being adapted, when the engine is in the diesel fuel operation mode, to deliver the control signal from said PID control circuit to said power amplifier circuit associated with said diesel fuel injection pump while leading the output of said voltage generating circuit, after converting said output of said voltage generating circuit into zero volt, to said power amplifier circuit associated with said gaseous fuel regulating valve, and said mode switching control means being further adapted, when the engine is in the gaseous fuel operation mode, to deliver the control signal from said PID control circuit to said power amplifier circuit associated with said gaseous fuel regulating valve while delivering the output from said voltage generating circuit, after converting said output of said voltage generating circuit into a voltage proportional to the rate of pilot injection of diesel fuel, to said power amplifier circuit associated with said diesel fuel injection pump.