Filter body for particle filter for treating exhaust gases from vehicle internal combustion engine, comprises filter blocks fixed using joints designed to reduce thermo-mechanical constraints

摘要

A filter body (3) comprises filter blocks fixed using joints (12) containing a number of joint sections designed locally to optimize the attenuation of thermo-mechanical constraints which can be generated in the filter body. A number of filter blocks (11b, 11f, 11i) are fixed into the body using at least one joint (12) inserted between the filter blocks and shaped to prevent the exhaust gases from passing between the filter blocks. At least two of the joint sections contain materials differing in their composition and/or structure and/or thickness. The materials of these joint sections have moduli of elasticity differing by at least 10% and at least one joint section has anisotropic elastic properties, made of a silica wafer impregnated with cement. The thicknesses of at least two joint sections differ by a ratio of at least 2. At least one joint section contains a vent opening onto the upstream or downstream face of the filter body. The vent is formed in a plane parallel to the faces of the filter blocks assembled by the joint section containing the vent. The length of the vent is 0.1-0.9 times the total length of the filter body and the vent is at least partially filled with a packing material which does not stick to the filter block or to the cement in the joint section it is cut in. The packing material is boron or silicon nitride. An Independent claim is also included for a particle filter for a vehicle exhaust comprising an envelope (5) and a filter body as above.