Abstract: A braking device for a valve controlled internal combustion engine for motor vehicles. Each cylinder has at least one exhaust valve, which is controllable for opening thereof by a camshaft having a main cam for moving operation and a supplementary cam which additionally becomes effective during braking operation. The supplementary cam is arranged in the plane of the main cam, and is capable of being lowered in the camshaft. The cam peak of the supplemental cam is arranged from 160.degree. to 200.degree. ahead of the main cam peak in the direction of rotation of the camshaft. The sides of the supplementary cam are embodied in such a way that upon reaching the upper dead center point, the exhaust valve associated therewith closes. The supplementary cam is capable of being actuated by a control shaft arranged in the rotational axis of the camshaft.

Abstract: A braking device for a valve controlled internal combustion engine for motor vehicles. Each cylinder has at least one exhaust valve, which is controllable for opening thereof by a camshaft having a main cam for moving operation and a supplementary cam which additionally becomes effective during braking operation. The supplementary cam is arranged in the plane of the main cam, and is capable of being lowered in the camshaft. The cam peak of the supplemental cam is arranged from 160.degree. to 200.degree. ahead of the main cam peak in the direction of rotation of the camshaft. The sides of the supplementary cam are embodied in such a way that upon reaching the upper dead center point, the exhaust valve associated therewith closes. The supplementary cam is capable of being actuated by a control shaft arranged in the rotational axis of the camshaft.

Abstract: A crank shaft for a multi-cylinder, short stroke internal combustion engine in which the diameters of the crank pin and of the shaft journal overlap each other, and in which the crank web decreases in thickness approximately from the center of the crank pin with increasing distance from the shaft center. In the crank webs within the region of the crank pin, relief bores are provided the axes of which are inclined with regard to the axis of said shaft journals. The relief bores are designed as blind bores with a flat bottom surface and with a circumferential surface merging with the flat bottom surface along a rounded surface section. The merging portion nearest to the area of the respective pertaining shaft journal is located approximately in the plane perpendicular to the longitudinal axis of the crank shaft and approximately in the middle between the crank pin and the shaft journal. With a diameter ratio of the crank pin to the shaft journal of about 0.