Abstract: An internal combustion engine is provided with a valve lift varying mechanism for intake valves and a valve phase varying mechanism for exhaust valves. A controller performs a control operation in response to a request to pause at least one cylinder while the engine is in operation. The control operation includes: a first operation of setting an intake valve lift to a zero-lift setpoint by the valve lift varying mechanism; and a second operation of setting an exhaust valve phase by the valve phase varying mechanism so as to set an exhaust valve opening timing to a first timing setpoint on an advance side of bottom dead center and set an exhaust valve closing timing to a second timing setpoint on a retard side of bottom dead center. The first and second timing setpoints are closer to top dead center than to bottom dead center.

Abstract: In a variable valve actuation system of an internal combustion engine employing a variable valve actuator capable of variably adjusting at least intake valve closure timing depending on engine operating conditions, a processor of a control unit is programmed to phase-advance the intake valve closure timing to a predetermined timing value after a piston top dead center position and before a piston bottom dead center position on intake stroke during at least one of an engine starting period and an engine stopping period. The variable valve actuator includes a biasing device by which the intake valve closure timing is permanently biased toward the predetermined timing value.

Abstract: A variable valve actuating apparatus for an internal combustion engine includes: a control shaft rotatably supported through a bearing to a body of the engine, and arranged to rotate about a center axis to control an operating state of an engine valve, the control shaft including; a control cam having a center which is off the center axis of the control shaft in a first direction; and a journal portion rotatably supported by the bearing, the journal portion having a center axis which is off the center axis of the control shaft in a second direction different from the first direction of the control cam.

Abstract: A variable valve actuation apparatus of an internal combustion engine has a multinodular-link motion converter, to vary at least a working angle. A position of rotation of a control shaft, variably adjusting the attitude of the motion converter, is set, so that, at a peak lift during a valve opening period, an angle ?2 between an extension line of a line segment connecting a first fulcrum corresponding to a drive-eccentric-cam center and a second fulcrum provided on a rocker arm and a line segment connecting the second fulcrum and a third fulcrum provided on the rocker arm at a position different from the second fulcrum at a middle working-angle control mode is less than both an angle ?1 between the two line segments at a minimum working-angle control mode and an angle ?3 between the two line segments at a maximum working-angle control mode.

Abstract: An internal combustion engine is provided with a valve lift varying mechanism for intake valves and a valve phase varying mechanism for exhaust valves. A controller performs a control operation in response to a request to pause at least one cylinder while the engine is in operation. The control operation includes: a first operation of setting an intake valve lift to a zero-lift setpoint by the valve lift varying mechanism; and a second operation of setting an exhaust valve phase by the valve phase varying mechanism so as to set an exhaust valve opening timing to a first timing setpoint on an advance side of bottom dead center and set an exhaust valve closing timing to a second timing setpoint on a retard side of bottom dead center. The first and second timing setpoints are closer to top dead center than to bottom dead center.

Abstract: A variable valve system has a drive shaft having a drive cam, a rockable cam opening/closing an engine valve, a transmission mechanism converting torque of the drive cam into a rocking motion and transmitting it to the rockable cam, a control shaft, and a control cam. When the variable valve system varies a valve lift amount of the engine valve by changing the rocking fulcrum of the transmission mechanism, the rocking fulcrum during a small valve lift control is set in an area outside an arc locus drawn with the drive shaft being a center of the arc and passing through a rocking fulcrum position positioned at a maximum valve lift and also inside an arc locus drawn with a pivot of the one end side of the transmission mechanism being a center of the arc and passing through the rocking fulcrum position positioned at the maximum valve lift.

Abstract: A variable valve actuating apparatus for an internal combustion engine includes a first valve actuating mechanism to vary a first valve operating condition, and a second valve actuating mechanism to vary a second valve operating condition. A controller controls the first valve actuating mechanism to satisfy a predetermined engine starting condition before a start of a cranking operation or during the cranking operation, with respect to an engine operating condition including the second valve operating condition controlled by the second valve actuating mechanism.

Abstract: A variable valve actuating apparatus for an internal combustion engine includes an intake valve operating angle varying mechanism, and an intake valve timing varying mechanism. The intake valve timing varying mechanism includes a housing rotating in synchronization with a crankshaft, and a vane member coupled to a drive shaft for intake valve operation, and movably mounted in the housing. The vane member includes a vane defining first and second fluid pressure chambers on first and second opposite sides of the vane. A hydraulic circuit is arranged to rotate the vane member relative to the housing by supply and return of a brake fluid to and from the first and second fluid pressure chambers so as to change the intake valve maximum lift phase. Coil springs are arranged to bias the vane member relative to the housing in a direction to retard the intake valve maximum lift phase.

Abstract: A variable valve system for an internal combustion engine includes a drive shaft rotated by an engine crankshaft, a drive cam integrally mounted on the drive shaft, first and second swing cams mounted on first and second engine valves in each engine cylinder, a valve lift mechanism for converting a rotational movement of the drive cam into swing movements of the first and second swing cams to open and close the first and second engine valves, and a control mechanism for controlling the operating position of the valve lift mechanism to vary the valve lifts of the first and second engine valves according to engine operating conditions. The valve lifts of the first and second engine valves are different from each other when the control mechanism performs minimum lift control on the valve lift mechanism to control the valve lifts of the first and second engine valves to minimum lifts.

Abstract: In a variable valve actuation system of an internal combustion engine employing a variable valve actuator capable of variably adjusting at least intake valve closure timing depending on engine operating conditions, a processor of a control unit is programmed to phase-advance the intake valve closure timing to a predetermined timing value after a piston top dead center position and before a piston bottom dead center position on intake stroke during at least one of an engine starting period and an engine stopping period. The variable valve actuator includes a biasing device by which the intake valve closure timing is permanently biased toward the predetermined timing value.

Abstract: In a variable valve actuation system of an internal combustion engine employing a variable valve actuator capable of variably adjusting at least intake valve closure timing depending on engine operating conditions, a processor of a control unit is programmed to phase-advance the intake valve closure timing to a predetermined timing value after a piston top dead center position and before a piston bottom dead center position on intake stroke during at least one of an engine starting period and an engine stopping period. The variable valve actuator includes a biasing device by which the intake valve closure timing is permanently biased toward the predetermined timing value.

Abstract: A valve operating apparatus for an internal combustion engine including a drive cam, first and second swing cams, first and second motion transmission mechanisms and first and second valve actuating members. The first and second swing cams are provided with identical swing motion characteristic with respect to a rotation angle of the drive cam through the first and second motion transmission mechanisms. The first swing cam and the first valve actuating member cooperate with each other to provide a valve lift amount of the engine valve for the first group of cylinders with respect to a swing angle of the first swing cam which is identical to a valve lift amount of the engine valve for the second group of cylinders with respect to a swing angle of the second swing cam.

Abstract: A variable valve actuating apparatus for an internal combustion engine includes a drive cam, a control shaft, a control cam, a rocker arm, and a swing cam. The drive cam is rotated by the internal combustion engine. The control shaft is supported for rotation about a rotation axis. The control cam is coupled to the control shaft, and is eccentric with respect to the rotation axis of the control shaft. The rocker arm is linked with the drive cam, and arranged to swing about the control cam in response to rotary motion of the drive cam. The rocker arm includes a recess slidably engaged with an outer radial periphery of the control cam. The swing cam is linked with the rocker arm, and arranged to swing in response to swinging motion of the rocker arm for opening and closing an engine valve of the internal combustion engine.

Abstract: A variable valve actuating apparatus for an internal combustion engine includes: a control shaft rotatably supported through a bearing to a body of the engine, and arranged to rotate about a center axis to control an operating state of an engine valve, the control shaft including; a control cam having a center which is off the center axis of the control shaft in a first direction; and a journal portion rotatably supported by the bearing, the journal portion having a center axis which is off the center axis of the control shaft in a second direction different from the first direction of the control cam.

Abstract: A variable valve actuation apparatus of an internal combustion engine has a multinodular-link motion converter, to vary at least a working angle. A position of rotation of a control shaft, variably adjusting the attitude of the motion converter, is set, so that, at a peak lift during a valve opening period, an angle ?2 between an extension line of a line segment connecting a first fulcrum corresponding to a drive-eccentric-cam center and a second fulcrum provided on a rocker arm and a line segment connecting the second fulcrum and a third fulcrum provided on the rocker arm at a position different from the second fulcrum at a middle working-angle control mode is less than both an angle ?1 between the two line segments at a minimum working-angle control mode and an angle ?3 between the two line segments at a maximum working-angle control mode.

Abstract: A variable valve system has a drive shaft having a drive cam, a rockable cam opening/closing an engine valve, a transmission mechanism converting torque of the drive cam into a rocking motion and transmitting it to the rockable cam, a control shaft, and a control cam. When the variable valve system varies a valve lift amount of the engine valve by changing the rocking fulcrum of the transmission mechanism, the rocking fulcrum during a small valve lift control is set in an area outside an arc locus drawn with the drive shaft being a center of the arc and passing through a rocking fulcrum position positioned at a maximum valve lift and also inside an arc locus drawn with a pivot of the one end side of the transmission mechanism being a center of the arc and passing through the rocking fulcrum position positioned at the maximum valve lift.

Abstract: In a multi-stage fuel-injection internal combustion engine employing a fuel injection system and a variable valve actuation system, engine valve timings are variably controlled depending on engine operating conditions. An electronic engine control unit is configured to execute cooperative control of the timing of sub-injection, injected before main injection, responsively to intake valve closure timing, and also to execute cooperative control of the timing of sub-injection, injected after the-main injection, responsively to exhaust valve open timing.

Abstract: In a control apparatus for controlling a variable valve actuation system employed in an internal combustion engine, engine/vehicle sensors are provided to detect at least a cylinder pressure in an engine cylinder for monitoring a change of state in combustion, arising from fluctuations in states/characteristics of air-fuel mixture such as a change in fuel property. Also provided is a control system that controls the variable valve actuation system responsively to a manipulated variable modified based on the cylinder pressure reflecting the change of state in combustion by a model of combustion.

Abstract: In a variably operated valve system for a compression ignition engine, an adjustment mechanism is controlled by means of a control section to detach an intake valve closure timing from a bottom dead center in accordance with an engine driving condition, and an engine start securing section guarantees an engine start even at least one of cases during a failure in the control section, during a stop of the engine, and during a start of the engine.

Abstract: A variable valve actuating apparatus for an internal combustion engine includes an intake valve operating angle varying mechanism, and an intake valve timing varying mechanism. The intake valve timing varying mechanism includes a housing rotating in synchronization with a crankshaft, and a vane member coupled to a drive shaft for intake valve operation, and movably mounted in the housing. The vane member includes a vane defining first and second fluid pressure chambers on first and second opposite sides of the vane. A hydraulic circuit is arranged to rotate the vane member relative to the housing by supply and return of a brake fluid to and from the first and second fluid pressure chambers so as to change the intake valve maximum lift phase. Coil springs are arranged to bias the vane member relative to the housing in a direction to retard the intake valve maximum lift phase.