Abstract: A combustion chamber structure for an internal combustion engine includes, in a piston top part, a concave portion formed eccentrically with respect to a cylinder center axis, and a tapered portion that connects an upper end face of the piston top part and a side face of the concave portion. The tapered portion is formed so that a tapered portion volume (volume of a space formed between the tapered portion and an upper wall surface of the combustion chamber) in a first portion of the piston top part is greater than a tapered portion volume in a second portion that is nearer than the first portion to an eccentric direction of the concave portion from the cylinder center axis.

Abstract: A supercharger control device for an internal combustion engine is preferably applied to a system having a first supercharger and a second supercharger. A switching supercharging pressure setting unit sets a switching supercharging pressure used in case of switching a mode for operating the first supercharger and the second supercharger, based on a difference between a target supercharging pressure and an actual supercharging pressure. When the actual supercharging pressure reaches the switching supercharging pressure, a switching control unit performs a control of switching the mode. Therefore, it becomes possible to appropriately prevent the overshoot of the supercharging pressure at the time of switching the mode.

Abstract: In a vehicle, which is provided with: a primary turbo and a secondary turbo, each of which is of an exhaust driven type; an exhaust changeover valve and an intake changeover valve, which are placed in a secondary exhaust passage and a secondary intake passage corresponding to the secondary turbo, respectively; and an intake bypass valve placed in an intake bypass passage, an ECU sets the opening/closing state of each changeover valve to an opening/closing state corresponding to a twin turbo mode at the time of engine stop, and it uses the drive control of each changeover valve which is necessitated in the transition to a single turbo mode at the engine start, thereby performing the sticking detection of the changeover valve at the same time.

Abstract: The subject is to efficiently detect the sticking of changeover valves for realizing a plurality of supercharging modes in a vehicle provided with a plurality of superchargers, and also to realize preferable fail-safe in cases where the sticking is detected. In a vehicle, which is provided with: a primary turbo and a secondary turbo, each of which is of an exhaust driven type; an exhaust changeover valve and an intake changeover valve, which are placed in a secondary exhaust passage and a secondary intake passage corresponding to the secondary turbo, respectively; and an intake bypass valve placed in an intake bypass passage, an ECU sets the opening/closing state of each changeover valve to an opening/closing state corresponding to a twin turbo mode at the time of engine stop, and it uses the drive control of each changeover valve which is necessitated in the transition to a single turbo mode at the engine start, thereby performing the sticking detection of the changeover valve at the same time.

Abstract: A supercharger control device for an internal combustion engine is preferably applied to a system having a first supercharger and a second supercharger. A switching supercharging pressure setting unit sets a switching supercharging pressure used in case of switching a mode for operating the first supercharger and the second supercharger, based on a difference between a target supercharging pressure and an actual supercharging pressure. When the actual supercharging pressure reaches the switching supercharging pressure, a switching control unit performs a control of switching the mode. Therefore, it becomes possible to appropriately prevent the overshoot of the supercharging pressure at the time of switching the mode.