A method for controlling a multi-cylinder combustion engine, wherein the combustion engine has a first operating state in which all cylinders are active, and a second operating state in which one of the multiple cylinders is active and one of the multiple cylinders is deactivated. The method comprises switching the combustion engine from the first to the second operating state, wherein, in the cylinder to be deactivated, an exhaust valve is deactivated after a combustion stroke and an intake valve is deactivated before an intake stroke following the combustion stroke in the closed state, and changing an ignition angle of the cylinder to be deactivated to an earlier ignition time and an optional change of the air/fuel mixture leads to a reduction in a temperature of an exhaust gas arising during the combustion stroke.

The invention relates generally valve train systems for internal combustion engine. More particularly, valve train configurations enable operation of a cylinder with two distinct, non-zero lift profiles and cylinder deactivation.

A valve train device, in particular for an internal combustion engine, includes a support element secured to a housing, at least one axially moveable cam unit associated with a valve, and at least one switch unit for axially moving at least one part of the cam unit having at least one displacement body which is provided to be introduced for axial movement at least functionally between the support element and the cam unit. The cam unit has at least three cam paths.

A camshaft for an engine and a method of assembling such a camshaft, wherein the camshaft has a base shaft and an external toothing which extends at least in certain portions axially along the base shaft A hub has an internal toothing which correlates with the external toothing of the base shaft such that the hub is connected rotationally conjointly and axially non-displaceably to the base shaft. The external toothing has at least one form-fit subregion, which extends axially at least in certain portions along the base shaft, or one force-fit subregion in order for the hub to be arranged at least in a form-fitting or force-fitting manner, and wherein at least the form-fit subregion or the force-fit subregion is adjoined by at least one alignment region which extends at least in certain portions axially along the base shaft and which serves for the angular alignment of the hub.

A sensor mounting structure for an engine is provided. The sensor mounting structure offers a greater flexibility in mounting a sensor which detects an operation of an actuation member disposed at an inner wall spaced apart from an outer wall of a cylinder head of a valve gear. A sensor mounting structure for an engine includes a valve gear provided at a cylinder head and a sensor detecting an operation of the valve gear. The sensor is mounted on a sensor mounting hole formed at a head inner wall of the cylinder head covered with a cylinder head cover.

A valve control for an internal combustion engine may include a tilt lever, a cam shaft, two cam groups arranged on the cam shaft, a roller bolt arranged on the tilt lever, and an adjusting assembly including a switching pin that engages through the roller bolt. The roller bolt may include two rotatable rollers. The switching pin may be adjustable into a switching position and into a home position. The switching pin may cooperate with a slotted guide of the cam shaft when in the switching position and may have no contact with the slotted guide when in the home position. When the switching pin is in the switching position, the two rollers may be axially adjustable via the adjusting assembly. The switching pin may be axially movable in the roller bolt and the two rollers may be axially movable on the roller bolt into one of two roller positions.

A valve train of an internal combustion engine may include a camshaft, first and second cams, a rocker arm assembly having a displacement bolt, which may be adjustable between at least first and second positions in the axial direction and on which at least one cam roller, may be mounted in an axially fixed and rotatable manner, wherein the displacement bolt may be mounted in associated bearing lugs of the rocker arm assembly, a guide contour arranged on the camshaft and having first and second guide tracks, a switching pin, which may be arranged in the displacement bolt and which may optionally engage with the first or second guide track to adjust the displacement bolt between the first and second positions. In the first and second positions, the cam roller may cooperate with the first and second cams, respectively. First and second catch recesses may be provided on the displacement bolt. A catch device may engage with a catch element, which may be biased into the first or second catch recess and which may secure the displacement bolt in the first or second position. The first and second guide tracks may cross one another in a crossing region. A third catch recess may be provided between the first and second catch recesses, wherein a first catch protuberance may be arranged between the first and the third catch recesses, and a second catch protuberance may be arranged between the second and the third catch recesses, wherein the catch element may engage with the third catch recess in the crossing region.

A valve train may include a camshaft, a cam sleeve adjustable in an axial direction between first and second positions and non-rotatably arranged on the camshaft, a first cam and at least one second cam, a pin and at least one cam follower mounted thereon, a guide contour arranged on the cam sleeve and having first and second guide tracks, and a control pin optionally engaging in the first or second guide track to adjust the cam sleeve between the first and second positions. The at least one cam follower in the first and second positions may interact respectively with the first and second cams. On the camshaft or an internal surface of the cam sleeve, first and second snap-in recesses and a third snap-in recess therebetween may be arranged. A snap-in device having a snap-in element preloaded into the snap-in recesses may be provided, the snap-in recess fixing the cam sleeve in the first or second position. The first and second guide tracks may intersect in an intersection region. Between the first and third snap-in recesses and between the second and third snap-in recesses, first and second snap-in humps may respectively be arranged. The snap-in element may engage in the third snap-in recess when the control pin is in the intersection region.

A valve drive device has a camshaft which includes a shaft element and a cam piece which can be driven by the shaft element and a first cam effecting a first stroke of a valve and a second cam effecting a second stroke of the valve, and is displaceable in the axial direction of the camshaft relative to the shaft element between a first position, in which the valve can be actuated by the first cam, and a second position in which the valve can be actuated by the second cam, and has an electrically controllable actuator via which the cam piece is displaceable relative to the shaft element in the axial direction as a result of an electrical control of the actuator. The actuator pushes the cam piece alternately back and forth between the positions in the case of successive electrical controls occurring with the same polarity.

Disclosed is a method and system for intermittently operating poppet valves in an internal combustion engine when desired by the selective locking or unlocking of one or more cam lobes with the camshaft. One or more cam lobes, with a small radial clearance, ride on a camshaft such that an engagement mechanism may be activated as desired to lock the cam lobe to the camshaft, thereby activating the respective poppet valve. The cam lobe is prevented from moving axially to ensure correct alignment with a follower. A suitable holding device may be used to ensure the non-activated cam lobes are restrained at a suitable orientation relative to the cam follower.