Abstract: Provided is an engine which is provided with an EGR device, wherein: an actual intake/exhaust gas pressure ratio ?1 of an intake-gas pressure P1 to an exhaust-gas pressure P2 is calculated from the detected exhaust-gas pressure P2 and the detected intake-gas pressure P1; an estimated intake/exhaust gas pressure ratio ?2 of the intake-gas pressure P1 to the exhaust-gas pressure P2 is calculated from an engine rotational frequency N, and a fuel injection amount F; and, in cases when the actual intake/exhaust gas pressure ratio ?1 is less than a prescribed value ?0, an EGR gas weight Megr is calculated based on the actual intake/exhaust gas pressure ratio ?1, and in cases when the actual intake/exhaust gas pressure ratio ?1 is equal to or more than the prescribed value ?0, the EGR gas weight Megr is calculated based on the estimated intake/exhaust gas pressure ratio ?2.

Abstract: An exhaust gas purifying apparatus includes an oxidative catalyst and a filter that are disposed in an exhaust gas path of an engine; a fuel injecting device that injects fuel according to a fuel injection pattern; and a control device that estimates a deposition amount of a particulate matter and sets the fuel injection pattern. When the fuel injection pattern including post-injection is set to recover the filter, the fuel injection pattern is set such that a post-injection amount is reduced as the deposition amount increases.

Abstract: An exhaust gas purifying apparatus includes an oxidative catalyst and a filter that are disposed in an exhaust gas path of an engine; a fuel injecting device that injects fuel according to a fuel injection pattern; and a control device that estimates a deposition amount of a particulate matter and sets the fuel injection pattern. When the fuel injection pattern including post-injection is set to recover the filter, the fuel injection pattern is set such that a post-injection amount is reduced as the deposition amount increases.

Abstract: Provided is an engine which is provided with an EGR device, wherein: an actual intake/exhaust gas pressure ratio ?1 of an intake-gas pressure P1 to an exhaust-gas pressure P2 is calculated from the detected exhaust-gas pressure P2 and the detected intake-gas pressure P1; an estimated intake/exhaust gas pressure ratio ?2 of the intake-gas pressure P1 to the exhaust-gas pressure P2 is calculated from an engine rotational frequency N, and a fuel injection amount F; and, in cases when the actual intake/exhaust gas pressure ratio ?1 is less than a prescribed value ?0, an EGR gas weight Megr is calculated based on the actual intake/exhaust gas pressure ratio ?1, and in cases when the actual intake/exhaust gas pressure ratio ?1 is equal to or more than the prescribed value ?0, the EGR gas weight Megr is calculated based on the estimated intake/exhaust gas pressure ratio ?2.