Filtering device for vehicle exhaust

Claim 1

A filtering device for temporary and direct attachment to an external end of an exhaust pipe of an internal combustion engine automobile to capture moisture and solid particles being discharged therefrom comprising a multiply bag having an open end sized to fit on and telescope on the end of the exhaust pipe of an automobile, said bag being elongated with a length at least greater than several times the width thereof, an inner ply woven bag formed of hydrophilic fibers for capturing moisture Droplets issuing with said exhaust gas and for capturing large diameter solid particles being discharged from the exhaust pipe, said inner ply bag defining a chamber into which the exhaust gas may diffuse, an outer ply woven bag formed of hydrophobic and fire resistant fibers positioned about said inner ply bag to resist the penetration of the sooty moisture and particles through to the outer surface of the filtering bag, an intermediate ply positioned between said inner ply bag and said outer ply bag, said intermediate ply being a nonwoven fibrous filter batt of fire resistant hydrophobic fibers and providing long tortuous passageways for capturing particles having passed through said inner ply, said intermediate ply being thicker than said inner and outer plies, means securing said bag plies together to define a unitary bag, and means collapsing said open end about and to said open end exhaust pipe for directly securing said filter bag about the exhaust pipe to permit the exhaust pipe to discharge therein.