Abstract: The invention relates to a soot-particle filter which is arranged in the exhaust-line system of an internal-combustion engine and which can be bypassed by means of a bypass line closable under full load. So that the vehicle can accelerate smoothly out of low speed ranges under full-load conditions, even when the filter is clogged, the bypass line is opened only when the speed of the internal-combustion engine is below a first speed limit value during its warm-up phase, when the speed of the internal-combustion engine is below a second speed limit value under hot-running conditions, and when, with the soot-particle filter clogged, the internal-combustion engine load is simultaneously below a predetermined load limit.

Abstract: A device for exhaust gas recirculation in diesel engines is described, in which an exhaust filter for the recirculated exhaust gas is arranged in an exhaust gas recirculation pipe branching off from the exhaust pipe. This exhaust filter insert is arranged in the branch of the exhaust gas recirculation pipe in such a way that its surface on the contamination side lies approximately parallel to the direction of flow of the main exhaust gas stream, to be precise in the region and course of a normal flow line close to the wall. In a preferred embodiment, the filter insert consists of a dimensionally stable porous pipe of sintered ceramic or sintered metal.

Abstract: A process for increasing the process temperature of an air compressing internal combustion engine includes mixing exhaust gas with the intake air. The amount of exhaust gas to be recirculated is set with reference to speed and load. To achieve an increased process temperature within a short period and with unrestricted internal combustion engine power, the intake air is preheated, taking into account a predetermined limit temperature of the coolant, when the engine is operating between a lower and upper speed range at 90% useful power. The intake air is also preheated in a subsequent speed range, extending up to 90% of the nominal engine speed, at 75% useful power of the engine. Exhaust gas is mixed in with the intake air between a medium to upper speed range and up to 75% of the useful power. The recirculated stream of exhaust gas is reduced, depending on the vehicle velocity and the percentage of useful power.