When an engine is started, an ECU determines whether an inside of a cylinder is in a wet concerned state in which there is a concern about fuel wet, or the inside of the cylinder is in a liquid particle float state in which a large volume of floating liquid particle of fuel arise. On determination that it is in the wet concerned state, the ECU performs a first control for reducing an intake air amount as a control of an opening timing and a closing timing by using the variable valve device. On determination that it is in the floating liquid particle state, the ECU performs a second control for increasing an in-cylinder temperature as a control of the opening timing and the closing timing by using the variable valve device.

A phase changing unit of the present invention changes the relative rotational phase of a first rotating body and a second rotating body, and includes: a rotating member to which an external drive shaft is connected and to which a rotational driving force is applied; and a relative rotation mechanism that generates a relative rotation between a first rotating body and a second rotating body by the rotation of the rotating member. The rotating member includes: an action part that is made of metal and acts on the relative rotation mechanism; a connection part which is made of resin and to which the drive shaft is connected; and a fragile part that is made of resin and functions to cut the transmission of a rotational force between the drive shaft and the rotating member when an excessive load has occurred.

When an operation state switches from a first operation region A to a second operation region B, the valve timing of an intake valve and an exhaust valve is switched upon switching of the operation state from the first operation region A to the second operation region B. When the operation state switches from the first operation region A to the second operation region B, the air-fuel ratio is switched after a first predetermined time T1 has elapsed since when the actual valve timing of the intake valve became a second intake valve timing and the actual valve timing of the exhaust valve became a second exhaust valve timing. In this way, it becomes possible to ensure ignition when the operation state switches.

A control device for an engine 1 including cylinders, and configured to perform a reduced-cylinder operation by idling some of cylinders. The control device includes a hydraulic valve-stopping mechanism 14b which closes the intake and exhaust valves 41, 51 of the cylinders in response to establishment of the reduced-cylinder operation execution condition, a hydraulic variable valve timing mechanism 19 capable of changing a phase of the exhaust valve 51 of the engine 1, and an ECU 110 which controls the valve-stopping mechanism 14b and the hydraulic variable valve timing mechanism 19. In response to establishment of the reduced-cylinder operation execution condition, the ECU 110 allows the hydraulic variable valve timing mechanism 19 to execute the phase change to the exhaust valve 51, and subsequently allows the valve-stopping mechanism 14b to bring the intake and exhaust valves 41, 51 of the cylinders into closed state.

A control device for an internal combustion engine includes an internal combustion engine and a valve opening-closing timing control device. The valve opening-closing timing control device has a phase adjustment mechanism for setting a relative rotation phase of a driving-side rotator and a driven-side rotator. The phase adjustment mechanism overlaps a timing of opening an intake valve with a timing of opening an exhaust valve, by setting, in a predetermined period, the relative rotation phase such that the exhaust valve closes after a top dead center position has been reached, and a bypass passage is provided that connects an exhaust passage of one cylinder that is in an exhaust process to the exhaust passage of another cylinder that is in an intake process at the same time as the exhaust process.

An internal combustion engine system includes an engine with a plurality of pistons housed in respective ones of a plurality of cylinders, an air intake system to provide air to the plurality of cylinders through respective ones of a plurality of intake valves, an exhaust system to release exhaust gas from the plurality of cylinders through respective one of a plurality of exhaust valves. The internal combustion engine uses vacuum braking and/or compression release braking in response to one or more braking conditions.

A valve timing adjustment device having a phase adjustment unit including an input rotator, a driving rotator that rotates in conjunction with a crankshaft, a driven rotator that rotates in conjunction with a camshaft that changes a relative rotation phase between the driving rotator and the driven rotator. A controller is configured to perform a startup phase control when operation of the internal combustion engine is started, the startup phase control including setting the relative rotation phase to a predetermined initial phase, and perform a startup preparation control during a period after the internal combustion engine is stopped and before the startup phase control is performed, the startup preparation control including changing the relative rotation phase.

Systems, apparatus and methods include control techniques for controlling operation of pre-mixed internal combustion engines in response to a load shedding event. The control techniques determine, in response to the load shedding event, a number of cycles in which to skip combustion of the fuel in the at least one cylinder based on an air-fuel ratio limit in the exhaust flow, prevent combustion of the fuel in the at least one cylinder during the number of skipped cycles, and combust the fuel in the at least one cylinder each time the number of skipped cycles are complete.

A system and method of controlling an angular position of a camshaft relative to an angular position of a crankshaft includes detecting rotational movement of an electric motor output shaft controlling a camshaft phaser; detecting rotational movement of the crankshaft; determining the relative difference between the rotational movement of the electric motor output shaft and the rotational movement of the crankshaft; and determining whether the angular position of the camshaft relative to the angular position of the crankshaft is advancing, retarding, or remaining constant.

Embodiments disclosed herein relate generally to systems and methods of operating internal combustion (IC) engines, and more specifically to systems and methods of starting compression ignition (CI) engines when the surrounding environment is significantly colder than the normal operating temperature of the engine (i.e., cold-starting). In some embodiments, the CI engine can include an ignition-assist device. In some embodiments, a method of operating a CI engine during cold-start can include opening an intake valve to draw a volume of air into the combustion chamber, moving a piston from a bottom-dead-center position to a top-dead-center position in a combustion chamber at a compression ratio of between about 15 and about 25, injecting a volume of fuel, the fuel having a cetane number of less than about 30, closing the intake valve, and combusting substantially all of the volume of fuel.