Abstract: An internal combustion engine for being mounted laterally on a saddle-type vehicle includes an AC generator disposed on an end portion of a crankshaft which is supported in a crankcase. An ACG cover covers the AC generator from outside widthwise across the vehicle. The ACG cover includes an electric power transmission line cover bulging portion covering electric power transmission lines extending to the ACG cover and bulging sideways outwardly widthwise across the vehicle. A crank angle sensor is disposed behind the electric power transmission line cover bulging portion in a vehicle front-back direction. The crank angle sensor is thus protected from flying stones, etc. without an increase in the number of parts used and an increase in the weight of the internal combustion engine.

Abstract: In an internal combustion engine in which a plurality of cylinders are arranged in series in a cylinder section, pressures of the cylinders can be detected by a smaller number of pressure sensors. An engine in which a plurality of cylinders are arranged in series in a cylinder section includes a communication path through which combustion chambers of the cylinders adjacent to each other communicate with each other, and a pressure sensor is disposed in the communication path.

Abstract: An internal combustion engine for being mounted laterally on a saddle-type vehicle includes an AC generator disposed on an end portion of a crankshaft which is supported in a crankcase. An ACG cover covers the AC generator from outside widthwise across the vehicle. The ACG cover includes an electric power transmission line cover bulging portion covering electric power transmission lines extending to the ACG cover and bulging sideways outwardly widthwise across the vehicle. A crank angle sensor is disposed behind the electric power transmission line cover bulging portion in a vehicle front-back direction. The crank angle sensor is thus protected from flying stones, etc. without an increase in the number of parts used and an increase in the weight of the internal combustion engine.

Abstract: In an internal combustion engine in which a plurality of cylinders are arranged in series in a cylinder section, pressures of the cylinders can be detected by a smaller number of pressure sensors. An engine in which a plurality of cylinders are arranged in series in a cylinder section includes a communication path through which combustion chambers of the cylinders adjacent to each other communicate with each other, and a pressure sensor is disposed in the communication path.

Abstract: An internal combustion engine is configured to satisfy the relation expressed by 0<Rv<0.000438×?2?0.0407×?+1.55 in a range of an intake valve overlap amount ?(°) from 20° to 45°, where Rv denotes an intake port volume ratio obtained by dividing an intake port internal volume Vp by a cylinder stroke volume Vc, and the intake valve overlap amount ?(°) is a crank angle from an intake valve opening timing when the intake valve starts opening to an intake top dead center of the piston. The engine improves output performance as well as both combustion performance and emission performance by suppressing reverse flow of the combustion gas into the intake system.

Abstract: An internal combustion engine is configured to satisfy the relation expressed by 0<Rv<0.000438×?2?0.0407×0+1.55 in a range of an intake valve overlap amount ?(°) from 20° to 45°, where Rv denotes an intake port volume ratio obtained by dividing an intake port internal volume Vp by a cylinder stroke volume Vc, and the intake valve overlap amount ?(°) is a crank angle from an intake valve opening timing when the intake valve starts opening to an intake top dead center of the piston. The engine improves output performance as well as both combustion performance and emission performance by suppressing reverse flow of the combustion gas into the intake system.

Abstract: An internal combustion engine is equipped with a variable valve control system which is operable to selectively actuate an engine valve using one of two cams of a camshaft, by sliding a rocker arm in the axial direction of a rocker-arm shaft. The system is capable of restricting the axial-direction movement of the rocker arm within a predetermined range, using a simple structure without unduly increasing the number of component parts. Position-restriction portions are formed in a rocker arm, and abut on a trigger arm to restrict sliding movement of the rocker arm within a predetermined amount, when the trigger arm is disengaged from the rocker arm.

Abstract: A control apparatus for a cylinder injection type internal combustion engine wherein the variable lift mechanism lessens the lift of the intake valve so as to set the time of opening the intake valve in a retarded angle position, in cold starting of the engine. The time of closing the exhaust valve is accordingly set in a retarded angle position.

Abstract: An object of the invention is to reduce an HC generated in a so-called fast idle period in which an engine and a catalyst are warmed up, stabilize a combustion and achieve an early activation of the catalyst, at a cold starting time of a cylinder injection type engine. In a control apparatus controlling a cylinder injection type internal combustion engine directly feeding a fuel into a combustion chamber by a fuel injection apparatus attached to a portion near an intake valve, the control apparatus controls the fuel injection apparatus so as to carry out an intake stroke injection, makes a lift amount of an intake valve smaller than a lift amount at a time of a high load, and controls such that an opening timing of the intake valve comes closer to an intake stroke side near an intake top dead center, in a fast idle period of the cylinder injection type internal combustion engine.

Abstract: An internal combustion engine is equipped with a variable valve control system which is operable to selectively actuate an engine valve using one of two cams of a camshaft, by sliding a rocker arm in the axial direction of a rocker-arm shaft. The system is capable of restricting the axial-direction movement of the rocker arm within a predetermined range, using a simple structure without unduly increasing the number of component parts. Position-restriction portions are formed in a rocker arm, and abut on a trigger arm to restrict sliding movement of the rocker arm within a predetermined amount, when the trigger arm is disengaged from the rocker arm.

Abstract: A control apparatus for a cylinder injection type internal combustion engine wherein the variable lift mechanism lessens the lift of the intake valve so as to set the time of opening the intake valve in a retarded angle position, in cold starting of the engine. The time of closing the exhaust valve is accordingly set in a retarded angle position.

Abstract: An object of the invention is to reduce an HC generated in a so-called fast idle period in which an engine and a catalyst are warmed up, stabilize a combustion and achieve an early activation of the catalyst, at a cold starting time of a cylinder injection type engine. In a control apparatus controlling a cylinder injection type internal combustion engine directly feeding a fuel into a combustion chamber by a fuel injection apparatus attached to a portion near an intake valve, the control apparatus controls the fuel injection apparatus so as to carry out an intake stroke injection, makes a lift amount of an intake valve smaller than a lift amount at a time of a high load, and controls such that an opening timing of the intake valve comes closer to an intake stroke side near an intake top dead center, in a fast idle period of the cylinder injection type internal combustion engine.

Abstract: There was a problem that various fuel spray shapes cannot be obtained according to operating conditions of a direct injection engine. There is provided a giant magnetostrictive element type injector which controls the change rate (rising slope) or peak value of a supply current applied to a solenoid for magnetic field generation which displaces a giant magnetostrictive element according to requests of an engine. The steeper the rising slope of the supply current to the solenoid, the higher becomes a lifting speed of a plunger, the higher becomes the initial speed of a fuel spray, and the longer the penetration can be. The gentler the rising slope thereof, the lower becomes the lifting speed of the plunger, the lower becomes the initial speed of the fuel spray, and the shorter the penetration can be.

Abstract: It is necessary to attain the combustion stability when performing ignition retarding in order to reduce exhaust gas and raise the exhaust gas temperature under a cold start condition, as well as soot reduction under a fully open throttle valve condition. An injector according to the present invention comprises: a plurality of fuel passages having an axis line inclined with respect to a valve operation axis line at a nozzle end; wherein inclined axis lines of at least three of the fuel passages have a spreading angle, none of them intersecting with each other, and three injection points are formed in a plane perpendicular to a valve operation axis line to form a triangle; and wherein at least one center-oriented fuel passage having an injection point around the center of the triangle is provided.