The present invention provides a variable valve mechanism of an internal combustion engine, which includes a rocker arm that includes a roller arm including a roller that rotatably abuts against a cam and a side arm provided at a side of the roller arm and that drives a valve, and a switching device that includes a switching pin and a hydraulic chamber provided inside the rocker arm and that switches a drive state of the valve by displacing the switching pin between a coupling position at which the switching pin extends between the roller arm and the side arm and a non-coupling position at which the switching pin does not extend between the roller arm and the side arm based on variations in hydraulic pressure in the hydraulic chamber. The switching pin is provided on an axis of the roller, and the hydraulic chamber is provided inside the roller arm.

An engine that can implement cylinder deactivation (CDA) includes: a plurality of cylinders; a variable valve duration apparatus that is mounted in at least one of the plurality of cylinders and that performs a long duration mode and a short duration mode of an intake valve of a corresponding cylinder; a CDA apparatus that is mounted in at least another one of the plurality of cylinders and that performs a general operation mode and a CDA mode of an intake valve and an exhaust valve of a corresponding cylinder; and a controller that controls operation of the variable valve duration apparatus and the CDA apparatus according to an operation state of an engine, wherein the controller controls the variable valve duration apparatus to operate in a short duration mode, when the CDA apparatus operates in the CDA mode.

A castellation device comprises a shaft surrounded by three castellation members. A first castellation member is rotatably mounted on the shaft and comprises a first end and a second end opposite to the first end. A second castellation member is slidably mounted along the shaft adjacent the first end of the first castellation member. A third castellation member is mounted to the shaft adjacent the second end of the first castellation member. A bias spring is disposed between the second castellation member and the third castellation member and is configured to bias the second castellation member away from the third castellation member. Optionally, an annular shroud can enclose the three castellation members. The first castellation member is rotatable relative to the second and third castellation members between a first position and a second position.

A method of providing a rocker arm set for a valvetrain includes providing a first intake rocker arm, a second intake rocker arm and a first exhaust rocker arm. The first intake rocker arm is configured as a switching rocker arm for a first intake valve on a first cylinder. The second intake rocker arm is for a second intake valve on a second cylinder. The second rocker arm is configured to operate in a normal Otto cycle mode. The first exhaust rocker arm is provided for a first exhaust valve on the second cylinder. The first intake rocker arm operates in one of an LIVC or EIVC mode where the first intake rocker arm is configured to open or close at a different time compared to the second intake valve. The first exhaust rocker arm operates in a cylinder deactivation mode.

A variable valve mechanism of an internal combustion engine includes a camshaft having a general shaft part and a cam part arranged next to each other in an axial direction, an input arm that swings when pressed by the cam part, an output arm that is swingably mounted and that drives a valve when swinging, and a switch device that switches the variable valve mechanism between a coupled state where the input arm and the output arm are coupled to swing together and an uncoupled state. The output arm has a great height so that clearance between the output arm and the general shaft part is 3 mm or less when the variable valve mechanism is in the coupled state and the valve is closed. If the output arm bounces in the uncoupled state, the output arm comes into contact with the general shaft part through the clearance.

Internal combustion engine having cam actuated valves that can be controlled to facilitate the use of different air charge levels in different cylinders or sets of cylinders are described. In one aspect a first set of cylinders is operated in a skip fire manner in which the corresponding cylinders are deactivated during skipped working cycles. Cam actuated intake valves associated with a second set of cylinders are operated differently so that the air charge in the cylinders in the second set is different than the air charge in fired cylinders subject to the skip fire control. According to another aspect, an engine having cam actuated intake valves is operated in a dynamic firing level modulation mode. During the dynamic firing level modulation operation, the cam actuated intake valves are controlled in at least two different manners to such that different cylinder working cycles have different air charges.

An actuation apparatus for actuating a component of a switchable valve train device of an internal combustion engine including: a shaft; an actuation lever mounted on the shaft for pivotal motion of the actuation lever between a first position for actuation of the component and a second position for de-actuation of the component; and a biasing means for urging the actuation lever from the second position towards the first position. In use, the biasing means is biased when an actuation source attempts to cause the actuation lever to be in the first position when the component is non-actuatable, such that the biasing means causes the actuation lever to pivot from the second position to the first position, thereby to actuate the component when the component becomes actuatable again.

An oil passage which supplies hydraulic oil to a cylinder deactivation apparatus (CDA) that operates by hydraulic pressure may include a high pressure passage, a low pressure passage, and an orifice, all of which may be integrally formed in either a cylinder head or a cam carrier. The high pressure passage may be connected to an oil supply apparatus and receive oil therefrom. The low pressure passage may be coupled to the high pressure passage and receive pressurized oil therefrom and form a low pressure relatively lower than a pressure in the high pressure passage. The low pressure passage may be connected to supply a hydraulic pressure to the CDA. The orifice may couple the high pressure passage to the low pressure passage, communicate the high pressure passage and the low pressure passage and may be formed to supply oil from the high pressure passage to the low pressure passage.

A dual body rocker arm for controlling a valve of a cylinder of an internal combustion engine includes: a first body; a second body; and a latching arrangement moveable to latch and unlatch the first body and the second body. The latching arrangement includes: a latch pin moveable between a first position in which the latch pin latches the first body and the second body together and a second position in which the first body and the second body are un-latched; and a lever mounted for pivotal motion relative to the first body, a first end of the lever contacting the latch pin, and a second end of the lever configured to contact an actuation arrangement. In use, when the actuation arrangement exerts a force on the second end of the lever, the lever pivots such that the first end of the lever exerts a force on the latch pin.

Systems and methods for operating an engine with deactivating and non-deactivating valves are presented. In one example, estimates of engine fuel consumption for operating the engine with a plurality of cylinder modes or patterns while a transmission is engaged in different gears are determined and are used as a basis for deactivating engine cylinders.