Methods and systems are provided for monitoring and controlling a cylinder valve deactivation mechanism. In one example, a method may include sending a lower command signal to a cylinder deactivation valve control (CDVC) system without actuating a cylinder valve transition, determining an impedance of a solenoid of the CDVC system while sending the lower command signal, and actuating the cylinder valve transition responsive to the determined impedance by sending a higher command signal to the CDVC system. In this way, the cylinder valve transition is performed when the impedance is high enough to prevent over-current.

An adjusting unit of an internal combustion engine is provided, comprising an electric motor and a transmission interacting therewith, an adjusting shaft of the transmission being coupled to the rotor of the electric motor. A drive shafts of the transmission coupled to the shaft which is to be adjusted. For controlling the electric motor, a sensorless control unit is provided outside of a housing of the electric motor which encloses the stator of the electric motor.

A variable camshaft timing (VCT) assembly for changing the angular position of concentric camshafts relative to a crankshaft includes a coupling plate having a first plurality of Oldham features configured to engage a first plurality of Oldham receiving features carried by a first VCT device and a second plurality of Oldham features configured to engage a second plurality of Oldham receiving features carried by a second VCT device; the coupling plate is positioned axially between the first VCT device and the second VCT device permitting the first VCT device and the second VCT device to move radially outwardly and inwardly relative to an axis of camshaft rotation.

A variable valve lift (VVL) system for an internal combustion engine is provided that utilizes hydraulic fluid supply pressure feedback to provide noise free operation. The VVL system includes a high pressure pump, a solenoid valve, a pressure translating device, a one-way valve, and a hydraulic fluid pressure sensor. The high pressure pump is fluidly connected to the solenoid valve and pressure translating device by at least one fluid gallery that forms a high pressure chamber. The solenoid valve selectively fluidly connects the high pressure chamber to a middle pressure chamber formed by at least one fluid gallery that fluidly connects the one-way valve to the solenoid valve. The hydraulic fluid pressure sensor is arranged to detect a hydraulic fluid supply pressure of the one-way valve and provides feedback to an electronic controller that determines a proper fluid intake opening timing of the solenoid valve.

An electrically-actuated VCT device cascaded controller, comprises: a system processing device configured to receive inputs from one or more sensors and generate an output signal that is communicated to an electric phaser motor; the system processing device: receives data indicating an angular position of a camshaft relative to an angular position of a crankshaft at a primary control loop; receives data indicating an angular velocity of the crankshaft at a secondary control loop; and generates the output signal that controls the electric phaser motor using the primary control loop and the secondary control loop.

A method of operating an internal combustion engine of a type that has a combustion chamber, a moveable valve having a seat formed in the combustion chamber, a camshaft on which a cam is mounted, and a rocker arm assembly having a rocker arm and a cam follower configured to engage the cam as the camshaft rotates. The method includes obtaining rocker arm position data, using the rocker arm position data to obtain camshaft position information, and using the camshaft position information in an engine management operation.

A variable valve timing control device includes a phase detecting portion; a phase control portion driving an electromagnetic solenoid while obtaining a detection signal detected by the phase detecting portion to set a spool to one of a phase control region and a lock region; and a boundary memory portion memorizing a boundary electric current value for referring a boundary between the phase control region and the lock region when the phase control portion operates a phase control; and a characteristic calculation portion obtaining the boundary electric current value by calculation, the boundary electric current value supporting the boundary between the phase control region and the lock region based on solenoid characteristic information of the electromagnetic solenoid and valve characteristic information of an electromagnetic control valve, the characteristic calculation portion memorizing the boundary electric current value to the boundary memory portion.

A variable valve lift (VVL) system for an internal combustion engine is provided that utilizes hydraulic fluid supply pressure feedback to provide noise free operation. The VVL system includes a high pressure pump, a solenoid valve, a pressure translating device, a one-way valve, and a hydraulic fluid pressure sensor. The high pressure pump is fluidly connected to the solenoid valve and pressure translating device by at least one fluid gallery that forms a high pressure chamber. The solenoid valve selectively fluidly connects the high pressure chamber to a middle pressure chamber formed by at least one fluid gallery that fluidly connects the one-way valve to the solenoid valve. The hydraulic fluid pressure sensor is arranged to detect a hydraulic fluid supply pressure of the one-way valve and provides feedback to an electronic controller that determines a proper fluid intake opening timing of the solenoid valve.

A rocker arm assembly includes an outer arm having first and second low lift lobe contacting surfaces, an inner arm, and a latch assembly. The inner arm includes first and second opposed sidewalls extending between a first end and a second end, and a high lift lobe contacting surface disposed between the first and second opposed sidewalls. The first end is pivotably secured to the outer arm and operably associated with an engine valve, and the second end is operably associated with a lash adjuster and defining a latch bore. The latch assembly is movable between a first configuration and a second configuration. In the first configuration, the latch assembly engages the outer arm such that the outer arm rotates with the inner arm, and in the second configuration, the latch assembly disengages the outer arm such that the outer arm rotates independently from the inner arm.

A camshaft adjusting system (1) is provided for a first camshaft (2) and a second camshaft (3) which are arranged concentrically with respect to one another, the second camshaft (3) being arranged within the first camshaft (2). A vane-cell type hydraulic camshaft adjuster (4) is configured for adjusting the first camshaft (2) and an electric camshaft adjuster (5) is configured for adjusting the second camshaft (3). A front cover (7) which is fastened to a stator (6) of the hydraulic camshaft adjuster (4) and which closes off the camshaft adjuster (4) at a side facing away from the camshaft has an internal toothing (8) for supporting a flex pot (9) which is attached to the second camshaft (3) and which is designed for receiving torque from the electric camshaft adjuster (5). A camshaft adjusting unit having the camshaft adjusting system (1) and two camshafts (2, 3) is also provided.