Abstract: A coolant jacket is provided for a liquid-cooled cylinder head for an internal combustion engine having a crankcase. The cylinder head has a gas exchange intake side having two gas exchange intake valves and a gas exchange exhaust side having two gas exchange exhaust valves. A fuel injection valve is provided on the intake side and an ignition device is provided on the exhaust side between the gas exchange valves. The coolant jacket extends as a first partial coolant jacket on the exhaust side, coming from the crankcase, between the gas exchange exhaust valves and then radially outside around the ignition device and the fuel injection valve and further in the direction of the intake side and the crankcase. Optimal cooling of the ignition device and the fuel injection valve is achieved which enables high specific powers and pressures leading to fuel consumption and cost advantages.

Abstract: A rocker assembly includes a central arm and two outer arms supported on a rocker shaft portion, and a plurality of supporting brackets. The arms, which are actuated by respective cams, actuate at least two lifting valves of a cylinder of an internal combustion engine. Both outer arms may be independently hydraulically coupled by bolt elements to the central arm. Hydraulic ducts extend through the supporting brackets, the rocker shaft portion and the outer arms to communicate with the coupling bolts. The rocker arms, the rocker shaft portion, and the supporting brackets form a pre-assembly unit. The central arm may have a roller on which an associated cam rolls, with the bolt elements of the central arm being arranged coaxially to the roller inside the roller.

Abstract: Disclosed is a method for the axial building up, in a vertical arrangement, of a hollow cylindrical soot body having no internal support and consisting substantially of silicon dioxide by means of at least one flame hydrolysis build-up burner serving for the soot production. In this method the soot is deposited at the beginning of the build-up onto an auxiliary body, and during the build-up the build-up burner and the growing soot body are rotated relative to one another, and the burner is at the same time held at an unvarying distance from the growing end of the hollow cylinder and centrally above the predetermined cross section of the upwardly growing end of the cylinder wall. The penetration of soot into the interior of the cylinder is prevented by means of a directed gas stream.