Abstract: A piston for balancing combustion efficiency and smoke generation with NOx production includes a combustion face forming a combustion bowl having a compound curvature increased in sharpness in a radially outward direction. An outer bowl surface defines a large radius of curvature adjacent an inner bowl surface, and a medium radius of curvature adjacent a cylindrical wall surface. The inner bowl, outer bowl, and wall surfaces together contour the combustion bowl, such that a diameter of the combustion bowl is about 124 mm so as to establish a bowl to bore ratio of about 0.71 in a direct injection compression ignition engine with a compression ratio of about 15:1 to 17:1.

Abstract: A piston for balancing combustion efficiency and smoke generation with NOx production includes a combustion face forming a combustion bowl having a compound curvature increased in sharpness in a radially outward direction. An outer bowl surface defines a large radius of curvature adjacent an inner bowl surface, and a medium radius of curvature adjacent a cylindrical wall surface. The inner bowl, outer bowl, and wall surfaces together contour the combustion bowl, such that a diameter of the combustion bowl is about 124 mm so as to establish a bowl to bore ratio of about 0.71 in a direct injection compression ignition engine with a compression ratio of about 15:1 to 17:1.

Abstract: The invention relates to a direct-injection internal combustion engine that is operated in a first operating range associated with the low part load, with largely homogeneous combustion of the mixture and subsequent injection. Said internal combustion engine is operated in a second operating range associated with the middle part load, with low-temperature combustion of the mixture. In this way, minimum nitrogen oxide and soot emissions and a high degree of efficiency can be achieved both in the lower part load region and up to the full load region.

Abstract: The invention relates to a variable valve train (1) for a cam-actuated lifting valve (13) of an internal combustion engine, which valve (13) is loaded by a closing spring (13a) acting against the direction of opening, with an approximately cylindrical force application element (2) located between a cam (14) and the valve (13), whose length can be adjusted hydraulically and whose exterior cylindrical wall face (3) is slidable in a fixed guide cylinder (4), said element (2) being provided with a pressure piston (6) longitudinally slidable in a cylinder (5), which piston (6) is adjacent to a pressure chamber (7) into which opens a pressure channel (8) departing from a port (9) in the wall face (3) of the force application element (2), a fixed pressure line (11) opening into the guide cylinder (4) in the area of the port (9), which line (11) can be subjected to hydraulic high pressure (pH) permitting hydraulic activation of the valve (13).

Abstract: A variable valve drive for a cam-actuated lift valve of an internal combustion engine which is loaded by a closing pressure against the direction of opening, includes a hydraulic power generating device acting on the lift valve against the closing force with a control piston arranged longitudinally displaceable in a cylinder and adjacent to a hydraulic control chamber, a stroke of the lift valve produced by an actuating cam being at least reducible by removing hydraulic liquid from the control chamber by means of a control valve. In order to arrange the valve stroke and valve opening as free as possible in the simplest possible way the control chamber is connectable with a high pressure level preferably by means of the control valve.

Abstract: The invention relates to a variable valve train (1) for a cam-actuated lifting valve (13) of an internal combustion engine, which valve (13) is loaded by a closing spring (13a) acting against the direction of opening, with an approximately cylindrical force application element (2) located between a cam (14) and the valve (13), whose length can be adjusted hydraulically and whose exterior cylindrical wall face (3) is slidable in a fixed guide cylinder (4), said element (2) being provided with a pressure piston (6) longitudinally slidable in a cylinder (5), which piston (6) is adjacent to a pressure chamber (7) into which opens a pressure channel (8) departing from a port (9) in the wall face (3) of the force application element (2), a fixed pressure line (11) opening into the guide cylinder (4) in the area of the port (9), which line (11) can be subjected to hydraulic high pressure (pH) permitting hydraulic activation of the valve (13).

Abstract: The invention relates to a variable valve drive for a cam-actuated lift valve of an internal combustion engine which is loaded by a closing pressure against the direction of opening, with a hydraulic power generating device acting on the lift valve against the closing force with a control piston arranged longitudinally displaceable in a cylinder and adjacent to a hydraulic control chamber, with a stroke of the lift valve produced by an actuating cam being at least reducible by removing hydraulic liquid from the control chamber by means of a control valve. In order to arrange the valve stroke and valve opening as free as possible in the simplest possible way it is provided that the control chamber is connectable with a high pressure level preferably by means of the control valve.

Abstract: The invention relates to a variable valve train (1) for a cam-actuated lifting valve (13) of an internal combustion engine, which valve (13) is loaded by a closing spring (13a) acting against the direction of opening, with an approximately cylindrical force application element (2) located between a cam (14) and the valve (13), whose length can be adjusted hydraulically and whose exterior cylindrical wall face (3) is slidable in a fixed guide cylinder (4), said element (2) being provided with a pressure piston (6) longitudinally slidable in a cylinder (5), which piston (6) is adjacent to a pressure chamber (7) into which opens a pressure channel (8) departing from a port (9) in the wall face (3) of the force application element (2), a fixed pressure line (11) opening into the guide cylinder (4) in the area of the port (9), which line (11) can be subjected to hydraulic high pressure (pH) permitting hydraulic activation of the valve (13).