Abstract: A piston for an internal combustion engine includes a piston body. The piston body includes a head, two side walls, two skirts, and a reinforcement member. The head includes a recessed crown. Each side wall includes a pin boss configured to support a piston pin. The two skirts are respectively located at a thrust side with respect to an axis of the piston pin and an anti-thrust side with respect to the axis of the piston pin. The reinforcement member includes two legs and a connecting portion connecting upper ends of the two legs. The two legs are respectively insert-casted in the two skirts. The connecting portion is insert-casted in the head.

Abstract: A piston for an internal combustion engine includes a piston body. The piston body includes a head, two side walls, two skirts, and a reinforcement member. The head includes a recessed crown. Each side wall includes a pin boss configured to support a piston pin. The two skirts are respectively located at a thrust side with respect to an axis of the piston pin and an anti-thrust side with respect to the axis of the piston pin. The reinforcement member includes two legs and a connecting portion connecting upper ends of the two legs. The two legs are respectively insert-casted in the two skirts. The connecting portion is insert-casted in the head.

Abstract: A first supercharger and a second supercharger are disposed in series in intake and exhaust passages. In a B region in which both the supercharging effects of the first and second superchargers are utilized, the opening of an exhaust control valve disposed in a passage for bypassing the turbine of the first supercharger is set to an intermediate degree, and the opening of an intake control valve disposed in a passage for bypassing the compressor of the first supercharger is set to the minimum. In a C region in which the supercharging effect of only the second supercharger is utilized, both the openings of the exhaust control valve and the intake control valve are set to the maximum. When the control region shifts from B region to C region as result of acceleration of the vehicle, the fuel injection amount is reduced over a predetermined period immediately after the shift.

Abstract: An apparatus for determining an abnormality of a control valve is applied to an internal combustion engine having a first supercharger, a second supercharger, a first control valve, and a second control valve. The apparatus includes an electronic control unit to obtain two supercharging-pressure-corresponding-values before and after an opening degree of the first control valve is changed during a period in which the engine is operated in a specific operating state under which the first supercharger supercharges the engine more efficiently than the second supercharger, and to determine whether or not the second control valve is abnormal based on the two values with respect to the change of the opening degree of the first control valve.

Abstract: A first supercharger and a second supercharger are disposed in series in intake and exhaust passages. In a B region in which both the supercharging effects of the first and second superchargers are utilized, the opening of an exhaust control valve disposed in a passage for bypassing the turbine of the first supercharger is set to an intermediate degree, and the opening of an intake control valve disposed in a passage for bypassing the compressor of the first supercharger is set to the minimum. In a C region in which the supercharging effect of only the second supercharger is utilized, both the openings of the exhaust control valve and the intake control valve are set to the maximum. When the control region shifts from B region to C region as result of acceleration of the vehicle, the fuel injection amount is reduced over a predetermined period immediately after the shift.

Abstract: An apparatus for determining an abnormality of a control valve, the apparatus being applied to an internal combustion engine having: a plurality of superchargers and a plurality of control valves, and carries out an abnormality determination of at least one control valve. The apparatus determines, based on each opening degree of control valves belonging to a first control valve group including only a part of the plurality of control valves and at least one of: a pressure of the air in at least one location in the intake air passage; and a pressure of the exhaust gas in at least one location in the exhaust gas passage, whether or not a control valve belonging to a second control valve group that includes control valves except for control valves belonging to the first control valve group among the plurality of control valves is abnormal.

Abstract: The present invention is applied to an internal combustion engine comprising a first supercharger 61, a second supercharger 62, a first control valve 66 for controlling a supply of an exhaust gas to the first supercharger, and a second control valve 64 for controlling a supply of an air to the first supercharger, and provides to an apparatus for determining an abnormality of a control valve which can determine abnormality of the first control valve and the second control valve. The apparatus for determining an abnormality of a control valve determines abnormality of a control valve when a supercharging pressure is smaller than a predetermined referential supercharging pressure by a predetermined value or more.

Abstract: The present invention is applied to an internal combustion engine comprising a first supercharger 61, a second supercharger 62, a first control valve 66 for varying an amount of an exhaust gas supplied to the first supercharger, a second control valve 64 for varying an amount of an air supplied to the first supercharger, and provides an apparatus for determining an abnormality of a control valve which can determine at least whether or not the second control valve is abnormal. The apparatus for determining an abnormality of a control valve provides, to the first control valve, an instruction to change an opening degree of the first control valve in a predetermined operating state.

Abstract: The present invention is applied to an internal combustion engine comprising a first supercharger 61, a second supercharger 62, a first control valve 66 for controlling a supply of an exhaust gas to the first supercharger, and a second control valve 64 for controlling a supply of an air to the first supercharger, and provides to an apparatus for determining an abnormality of a control valve which can determine abnormality of the first control valve and the second control valve. The apparatus for determining an abnormality of a control valve determines abnormality of a control valve when a supercharging pressure is smaller than a predetermined referential supercharging pressure by a predetermined value or more.