A controller for controlling an internal combustion engine includes a valve timing adjuster, a variable valve lift mechanism and a processor. The processor controls a duty cycle of a drive signal in a selected one of control modes, thereby changing a relative rotational phase of a camshaft relative to an engine output shaft. The control modes include a specific control mode in which the duty cycle of the drive signal is adjusted to change a value of the current through a first motor. The processor performs, when changing the relative rotational phase through execution of the specific control mode, an abnormality diagnosis for the variable valve lift mechanism based on a comparison between the current value at the first motor and a reference current value. The processor sets the reference current value in accordance with a rotation angle of the output shaft of a second motor.

Methods and systems are provided for deactivating a valve actuation mechanism. In one example, a system may include a hydraulic gallery that may deliver a restricted flow of hydraulic fluid from a hydraulic flow restrictor to a pressure relief valve within a valve deactivation oil control valve, and during a second condition may deliver an unrestricted flow of hydraulic fluid from the valve deactivation oil control valve to the hydraulic flow restrictor. The hydraulic flow restrictor may comprise two vertical bores within the camshaft carrier that are fluidically coupled via a restrictive groove on the bottom surface of the camshaft carrier.

An internal combustion engine is provided with a plurality of cylinders, air intake valves provided to each of the cylinders, and a variable valve actuation mechanism for varying the valve actuation of the air intake valves. A motor drives the variable valve actuation mechanism. A motor controller controls the motor. The internal combustion engine is capable of operating in a cylinder deactivation mode, in which the air intake valves of some of the cylinders are kept shut. When the internal combustion engine is reactivated from the cylinder deactivation mode, the motor controller executes an air intake amount correction process, in which the opening duration of the air intake valves is temporarily increased, thereby increasing the amount of air taken in by operating cylinder for which the air intake valves have been opened or closed even during the cylinder deactivation mode.

A variable valve operating system assembled in an engine includes a first rocker arm contacting with a valve, a second rocker arm no contacting with any valve, a lost motion spring bringing the second rocker arm into contact with a cam, and switching device for switching the first/second rocker arms to a coupled or uncoupled state. An operation control apparatus for the engine includes element for determining whether or not an engine speed is higher than a first speed at which supply of fuel is allowed to be temporarily stopped, and element for setting a requested quantity of increase/decrease in internal resistance of the engine. When the engine speed is higher than the first speed and an accelerator opening degree is 0%, the switching device switches the first/second rocker arms to the coupled or uncoupled state based on the requested quantity.

A switching roller finger follower (SRFF) for valve actuation includes an outer arm (16), a first inner arm (12), a bearing axle (50) and a latch pin (26). The outer arm (16) is formed of a metal stamping, and is pivotally coupled to a main axle (40). The first inner arm (12) is coupled to the main axle (40) and is pivotably secure to the outer arm. The bearing axle (50) extends through the outer arm and the first inner arm. The bearing axle supports a roller (20) thereon. The latch pin (26) is slidably disposed in the outer arm (16) and is movable between at least a first position where the outer arm (16) and the first inner arm (12) are coupled for concurrent rotation and a second position wherein one of the outer arm and the first inner arm are configured to rotate relative to the other arm.

An actuation transmission apparatus for actuating a latching arrangement for latching and unlatching a first body and a second body of a switchable valve train component of an internal combustion engine, the latching arrangement being biased from an unlatched position where the first body and the second body are unlatched towards a latched position where the latching arrangement latches the first body and the second body together, the actuation transmission apparatus including: a shaft rotatable by an actuation source; a contacting element for contacting the latching arrangement; and a biasing device for biasing the contacting element rotationally with respect to the shaft. In use, the biasing device becomes biased by the shaft when the actuation source rotates the shaft when the actuation source attempts to actuate the latching arrangement to the unlatched position, via the contacting element, when the latching arrangement is in an un-actuatable state.

A switching finger may operate in two or three states or positions and cooperate with a single motion source to achieve methods of operating an engine in corresponding two or three modes. The modes may include cylinder deactivation, main event or auxiliary modes, including lost motion braking, LIVC and EEVO. A follower for an engine valve train utilizes an adjustable support assembly that eliminates potential for partial engagement during operation. A lever engagement member or latch is disposed for movement on the follower body and interacts with a lever to provide a constant contact geometry. The latch may support the lever in one or more precise positions, or permit the lever to pivot free of the latch for complete lost motion, as in cylinder deactivation applications.

A rocker arm assembly includes a rocker arm configured to rotate about a rocker shaft and having a valve side end configured to selectively engage an engine valve, and a cam side end configured to be selectively engaged by a camshaft. A cylinder deactivation (CDA) capsule is coupled to the cam side end and includes an outer body having at least one slot formed therein, the outer body configured to be coupled to the rocker arm, and an inner plunger at least partially received within the outer body and having at least one outwardly extending tab. The inner plunger is configured to translate within the outer body, and the at least one outwardly extending tab is received within the at least one slot and a groove formed in the rocker arm to facilitate preventing rotation of the inner plunger and outer body relative to the rocker arm.

A method of providing diagnostic information for an electromagnetic latch assembly (122) includes providing a pulse to a circuit (200) that include one or more electromagnetic latch assemblies. The circuit (200) includes coils (199) of the electromagnetic latch assemblies. Each coil is inductively coupled with an armature (131) that is mechanically coupled to a latch pin (118). The circuit (200) is pulsed and a DC current in the circuit (200) that results from the pulse is measured over a first interval to determine a primary response. The current in the circuit (200) over a second interval is measured to determine a reference response. A second pulse may be used to generate the current for the reference response. The primary response and the reference response are compared to provide diagnostic information relating to position or movement of one or more of the latch pins (118).

An internal combustion engine switches valve operation states, reduces or prevents wear of a cam and a rocker arm, and reduces the size of the cylinder head to ensure a sufficient valve lift amount. A valve spring retainer includes a cylindrical portion including a first through hole with an inner diameter decreases from the first end portion toward the second end portion, a cone-shaped portion including a second through hole with an inner diameter increases as it extends away from the second end portion of the cylindrical portion, and a flange portion extending radially outward from the cone-shaped portion. An outer diameter of the cylindrical portion is constant from the first end portion to the second end portion, and an outer diameter of the cone-shaped portion increases as it extends away from the second end portion.