Abstract: An electrical heating unit H for introduction into the exhaust gas system of an internal combustion engine, in particular upstream with respect to an exhaust gas purification unit, for instance a catalytic converter, which for its operation requires a temperature higher than the ambient temperature, comprises a casing (13) and at least one resistance heating element (14) which is designed as a band and is retained inside the casing (13), wherein the at least one heating band (14) is arranged so that it runs in a meandering pattern and with its flat face parallel or substantially parallel to the longitudinal axis of the casing (13). The heating unit H also comprises at least one support structure (19, 19.

Abstract: An electrical heating unit H for introduction into the exhaust gas system of an internal combustion engine, in particular upstream with respect to an exhaust gas purification unit, for instance a catalytic converter, which for its operation requires a temperature higher than the ambient temperature, comprises a casing (13) and at least one resistance heating element (14) which is designed as a band and is retained inside the casing (13), wherein the at least one heating band (14) is arranged so that it runs in a meandering pattern and with its flat face parallel or substantially parallel to the longitudinal axis of the casing (13). The heating unit H also comprises at least one support structure (19, 19.

Abstract: The invention relates to a particulate filter (1) designed as a partial filter, particularly as a soot particulate filter for removing soot particles from the exhaust gas flow of an internal combustion engine, said filter comprising a filter block unit (3) that is held in a filter housing (2), is designed as a channel filter and comprises a plurality of parallel channels (6, 6.1) which are separated from one another by filter walls (7). The filter block unit (3) comprises at least two filter blocks (5, 5.1) connected one behind the other in the direction of the exhaust gas flow. Each filter block (5, 5.1) is designed as a partial filter, with a first plurality of the channels of each filter block (5, 5.1) being open on the outflow side, and a further plurality thereof being closed on said outflow side.

Abstract: A method for lowering the ignition temperature of soot accumulated on a particulate filter 2 installed in exhaust tract 1 of an internal combustion engine is described. In this method, a precursor of a catalyst which lowers the oxidation temperature of soot is introduced into exhaust tract 1 downstream from the internal combustion engine and upstream from particulate filter 2. The precursor introduced into exhaust tract 1 is converted to its gaseous phase within exhaust tract 1 prior to contacting the soot accumulated on particulate filter 2. The gaseous catalyst precursor is adsorbed by the soot accumulated on particulate filter 2. Subsequently the catalyst responsible for lowering the ignition temperature is formed from the gaseous precursor in a reaction with at least one other component contained in the exhaust gas flow.

Abstract: The aim of the invention is to provide filtering candles (1) comprising a sintered filtering tube (2) and a collar (3) which is connected thereto, and having an increased shelf life and improved resistance values. To this end, the collar (3) comprises an annular collar wall (4) which oriented towards the filtering tube (2) from the neck. Said wall comprises at least one recess (8) which is arranged in a perpendicular manner and at an angle in relation to a plane which is perpendicular to the axis of the filtering tube.

Abstract: The aim of the invention is to provide filters with a graduated structure, which are simple to produce and exhibit excellent properties in terms of their permeability to liquids and/or gases. To achieve this, the filters are produced from sinterable material consisting of at least two layers of differing pore size, a first layer having a minimum pore size of 0.005 &mgr;m and consisting of metal oxide or mixtures of metal oxide and the additional layer that is connected to the first layer consisting of a material other than metal oxide. The invention also relates to a method for producing the inventive filters and to the use thereof.

Abstract: The aim of the invention is to provide filtering candles (1) comprising a sintered filtering tube (2) and a collar (3) which is connected thereto, and having an increased shelf life and improved resistance values. To this end, the collar (3) comprises an annular collar wall (4) which is oriented towards the filtering tube (2) from the neck. Said wall comprises at least one recess (8) which is arranged in a perpendicular manner and at an angle in relation to a plane which is perpendicular to the axis of the filtering tube.