A sleeve includes: a supply port communicated with a hydraulic oil supply source; a primary control port communicated with a retard chamber, a secondary control port communicated with an advance chamber; and a drain port communicated with an outside of a valve timing adjustment device. A spool includes: a pressure accumulation space formed at an inside of the spool; a supply passage configured to connect between the pressure accumulation space and the supply port; a primary control passage configured to connect between the pressure accumulation space and the primary control port; a secondary control passage configured to connect between the pressure accumulation space and the secondary control port; and a recycle passage configured to connect between the primary control port or the secondary control port and the pressure accumulation space. The recycle passage and the drain port are connected with each other at the inside of the sleeve.

The present disclosure relates to a variable valve drive, in particular with a sliding cam system, for an internal combustion engine. The variable valve drive has a shaft and a cam carrier which is arranged rotationally conjointly and axially displaceably on the shaft and which has a first cam and a second cam. The variable valve drive has an actuator device for axially displacing the cam carrier, and has a carrying device which at least partially engages around a lever axle of a force transmission device and carries the actuator device. The variable valve drive can offer the advantage that an arrangement of the actuator device which is expedient in terms of structural space is made possible in the region of the lever axle. At the same time, support of the actuator device by means of the carrying device on the lever axle can stiffen the flexible lever axle by means of the engaging-around configuration.

The application relates to an electromagnetic control device, in particular for adjusting camshafts or a camshaft section of an internal combustion engine, comprising: an energizable coil unit via which, in the energized state, an armature mounted for movement along a longitudinal axis of the control device can be moved relative to a pole core between a retracted position and an extended position; a tappet which interacts with the armature and is mounted for movement along the longitudinal axis, having a free end, via which the tappet interacts with the camshaft in the extended position in order to adjust the camshaft; and an adapter, via which the control device can be fastened to a component, in particular to cylinder head cover, wherein the armature and the tappet are connected to each other for conjoint rotation, and the control device has a first bearing section inside the adapter for rotatable mounting of the tappet and a second bearing section outside of the adapter for rotatable mounting of the tappet and/or the armature.

An actuation arrangement for actuating a plurality of latching arrangements of a respective plurality of dual body rocker arms of a valve train assembly of an internal combustion engine includes: a first shaft comprising one or more first selector cam for controlling the latching arrangements of a first group of one or more of the dual body rocker arms; and a second shaft comprising one or more second selector cams for controlling the latching arrangements of a second group of one or more of the dual body rocker arms. At least a portion of the first shaft is received in the second shaft, and the first shaft and the second shaft are controllable to rotate independently of one another, thereby to allow control of the latching arrangements of the dual body rocker arms on a per group basis.

The present disclosure relates to a sliding cam system for an internal combustion engine. The sliding cam system has a camshaft and a plurality of cam carriers with in each case at least two cams, the plurality of cam carriers being arranged fixedly on the camshaft so as to rotate with it and in an axially displaceable manner. The sliding cam system has a plurality of fluid-actuated actuator apparatuses which are configured in each case for axially displacing a cam carrier of the plurality of cam carriers. The sliding cam system has a fluid feed apparatus which is provided for feeding a fluid in a fluidic connection upstream of the plurality of actuator apparatuses for actuating the plurality of actuator apparatuses. At least two actuator apparatuses of the plurality of actuator apparatuses are coupled fluidically for simultaneous actuation.

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.

A system for actuating engine valves may include a valve bridge having a main event rocker interface portion, a first valve interface portion and a second valve interface portion extending in generally opposite directions from the main event rocker interface portion. The second valve interface portion may include an open end including a slot for receiving a bridge pin. The slot permits the valve bridge to be removed from the actuation system without removal of the main event rocker or other actuating components, such as an auxiliary rocker. The valve bridge can be removed from the valve train without requiring removal of other actuation system components, such as auxiliary rockers or main event rockers. A single valve bridge configuration can be used with different valve spans, which may occur among different cylinder sizes in a given engine family, or across different engine families.

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 module of a variable valve drive of an internal combustion engine is proposed that includes a push rod mounted longitudinally in a cylinder head of the internal combustion engine. The push rod is actuated by a linear actuator that includes an armature that makes contact, at least indirectly with the push rod, to displace it in a first longitudinal direction. A switchable rocker arm with a coupling slide arranged transversely to a longitudinal extent or side of the rocker arm corresponds to an actuating finger that extends from the push rod. The coupling slide includes a slide part that projects laterally from the rocker arm and can be acted upon by a free end of the actuating finger. Kinetic energy of the push rod is dissipated or converted at least partially via a separate damper in the first longitudinal direction before it reaches a final position.

A switchable lever arrangement is provided that includes at least one switchable lever and a rotary actuator. The at least one switchable lever includes an outer lever, an inner lever pivotably mounted to the outer lever, and a locking part that selectively locks the inner lever to the outer lever. The rotary actuator rotates about a rotational axis to actuate the locking part. The rotary actuator has a first locked position defined by a first effective actuation length, and a second unlocked position defined by a second effective actuation length, with the second actuation length different than the first actuation length.