Abstract: In a gas exchange valve operating apparatus with at least one overhead camshaft for actuating the gas exchange valves, with a hydraulic medium supply passage extending through the camshaft and with at least one hydraulic switchable support unit cooperating with a lever-like cam follower which is disposed on a switchable support unit and on a gas exchange valve and is furthermore in contact with the overhead camshaft, the support unit is disposed in communication with at least one pressure medium supplied via the hydraulic medium supply passage of the camshaft.

Abstract: In a gas exchange valve operating apparatus with at least one overhead camshaft for actuating the gas exchange valves, with a hydraulic medium supply passage extending through the camshaft and with at least one hydraulic switchable support unit cooperating with a lever-like cam follower which is disposed on a switchable support unit and on a gas exchange valve and is furthermore in contact with the overhead camshaft, the support unit is disposed in communication with at least one pressure medium supplied via the hydraulic medium supply passage of the camshaft.

Abstract: In a bearing for a crankshaft of an internal combustion engine having a crankcase including a bearing base portion with a bearing cover mounted thereon and both the bearing base portion and the bearing cover consisting of a light metal alloy, the bearing cover has removably mounted therein, adjacent the crankshaft, an insert consisting of a bearing material which has a lower coefficient of thermal expansion than the light metal alloy of which the base bearing portion and the bearing cover consist.

Abstract: The invention relates to a device for angularly adjusting an internal combustion engine camshaft in relation to a crankshaft and comprises an adjusting bushing connected to the camshaft, with an input sleeve surrounding said bushing, and with an actuator displaceably arranged there between. An input sleeve, the actuator, and the adjusting bushing are each provided with helical gear teeth to translate axial shifting of the actuator into relative rotation between the camshaft and crankshaft. In order to prevent rattling noises in the gear teeth that are caused by changing moments in the drive of the camshaft, the actuator is guided in stop-free fashion. A stop, which is effective between the input sleeve and camshaft, limits the angular adjustment so that the actuator is stressed between the input sleeve and camshaft to avoid backlash during rattling.