Abstract: Motor control means of a motor poppet valve has initial motor torque setting means for setting the initial motor torque of an electric motor so that the initial motor torque equals a torque corresponding to a force biasing a valve element of a poppet-valve body toward a valve seat or a proximate value, and drives the electric motor so as to obtain the initial motor torque when driving the electric motor to detach the valve element from the valve seat.

Abstract: An auxiliary agent supply means (32, 58) is provided to supply, upstream of an exhaust gas purification means (24, 56, 78), an auxiliary agent for maintaining the exhaust gas purifying function of the exhaust gas purification means (24, 56, 78). A control means (38) for controlling the auxiliary agent supply means (32, 58), thereby regulating the amount of the auxiliary agent supplied includes a standard supply quantity determination section (40, 50, 68, 86) for determining standard supply quantity of the auxiliary agent required to maintain the exhaust gas purifying function, a target supply quantity determination section (42, 52, 70, 88) for determining target supply quantity of the auxiliary agent, by correcting the standard supply quantity on the basis of exhaust pressure, and a supply control section (44, 54, 72, 90) for controlling the auxiliary agent supply means to supply the auxiliary agent in the target supply quantity.

Abstract: An EGR control device includes an EGR control means (44) which, when a large-amount EGR is requested, continuously controls an EGR valve (26) toward a fully open condition, and then continuously controls an intake throttle valve (12) toward a fully closed condition, and in a dead region where a change in the opening of the intake throttle valve only causes a small change in EGR quantity, the control means restricts a feedback control of the EGR quantity using the intake throttle valve and performs a feedback control of the EGR quantity using the EGR valve to compensate for the restriction of the feedback control using the intake throttle valve.

Abstract: A fuel injection system that can be used in a diesel engine is provided. The system includes a first accumulator for storing high-pressure fuel and a second accumulator for storing low-pressure fuel sufficiently lower in pressure than the fuel stored in the first accumulator. There is a first two-way electromagnetic valve disposed in a first fuel passage connecting the first accumulator with a fuel injection nozzle. A flow control apparatus controls a flow rate of fuel passing through a second fuel passage connecting a downstream side of the first two-way electromagnetic valve in the first fuel passage with the second accumulator. The flow control apparatus is placed in the second fuel passage. A second two-way electromagnetic valve is placed in a third fuel return passage which connects the fuel injection nozzle with a fuel tank. The second two-way electromagnetic valve switches the fuel injection modes of the fuel from its injection mode to its uninjection mode or vice versa.