Method of removing particulates from exhaust gases, and corresponding fiber layer, particulate filter, exhaust system and vehicle
AssigneesEMITEC Gesellschaft fuer Emissionstechnologie mbH, Toyota Motor Corporation
InventorsPeter Hirth, Rolf Brück, Thomas Härig
Life of this patent
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Abstract
A method for removing particulates from a gas stream includes providing a gas-permeable filter layer having subregions with a parameter of differing magnitudes in the direction of the layer thickness. This parameter relates at least to the porosity, the fiber diameter of fibers or the fiber type content of the filter layer. The gas stream is divided into partial gas streams which are each passed through different subregions of the filter layer. Fiber layers, particulate filters, exhaust systems and vehicles based on this method are also provided.
Claims24
A fiber layer for use in an exhaust system of a mobile internal combustion engine, the fiber layer comprising:
- an assembly formed only of combinations of fibers;
- two opposite surfaces of the fiber layer defining a layer thickness extending between said surfaces;
- a porosity parameter characterizing the fiber layer;
- said porosity parameter having a magnitude varying in direction of said layer thickness;
- and
- said magnitude having an extreme representing a minimum value at a distance from said surfaces of the fiber layer.
A particulate filter for use in an exhaust system of a mobile internal combustion engine, the particulate filter comprising:
- a honeycomb body having at least one fiber layer formed only of combinations of fibers and at least one at least partially structured sheet together forming channels, at least some of said channels having at least one microstructure;
- said at least one fiber layer having two opposite surfaces defining a layer thickness extending between said surfaces and a porosity parameter having a magnitude varying in direction of said layer thickness;
- and
- said magnitude having an extreme representing a minimum value at a distance from said surfaces of said at least one fiber layer.
A method for removing particulates from a gas stream, the method comprising the following steps:
- providing a gas-permeable filter layer formed only of combinations of fibers, and having a layer thickness and subregions with a porosity parameter of differing magnitudes in direction of the layer thickness;
- providing the filter layer with two opposite surfaces defining a layer thickness extending between the surfaces;
- providing the magnitudes with an extreme representing a minimum value at a distance from the surfaces of the filter layer;
- and
- dividing the gas stream into partial gas streams each passing through different subregions of the filter layer.
A fiber layer for use in an exhaust system of a mobile internal combustion engine, the fiber layer comprising:
- an assembly of fibers;
- two opposite surfaces defining a layer thickness extending between said surfaces;
- an odd number of subregions in direction of said layer thickness including a centrally disposed subregion and other subregions;
- said subregions having fiber diameters;
- and
- said fiber diameter of said centrally disposed subregion being larger or smaller than said fiber diameters of said other subregions.
A particulate filter for use in an exhaust system of a mobile internal combustion engine, the particulate filter comprising:
- a honeycomb body having at least one fiber layer and at least one at least partially structured sheet together forming channels, at least some of said channels having at least one microstructure;
- said at least one fiber layer having two opposite surfaces defining a layer thickness extending between said surfaces, and an odd number of subregions in direction of said layer thickness including a centrally disposed subregion and other subregions, said subregions having fiber diameters, and said fiber diameter of said centrally disposed subregion being larger or smaller than said fiber diameters of said other subregions.
A method for removing particulates from a gas stream, the method comprising the following steps:
- providing a gas-permeable filter layer having fibers, two opposite surfaces defining a layer thickness extending between the surfaces and an odd number of subregions in direction of the layer thickness including a centrally disposed subregion and other subregions, the subregions having fiber diameters, and the fiber diameter of the centrally disposed subregion being larger or smaller than the fiber diameters of the other subregions;
- and
- dividing the gas stream into partial gas streams each passing through different subregions of the filter layer.
Dependencies are inferred from the claim text.