Abstract: Apparatus for controlling emissions from an internal combustion engine including an enclosed cylindrical housing and a converter assembly coaxially mounted in the housing for reducing noxious gases emitted from the engine. The converter assembly is characterized by a catalytic module transversely disposed within the housing at a predetermined location between an inlet and an outlet, thereof. The center of the catalytic module is formed by a cylindrical hub closed against flow of exhaust gases therethrough, surrounded by a catalytic cell of annular cross-section through which exhaust gases from the engine may flow, converting nitrogen oxides, carbon monoxide and unburned hydrocarbons to less noxious compounds before being discharged through the outlet. The hub is normally closed against flow of exhaust gases by a closure member. The closure member is openable in response to abnormal increases in pressure from the engine exhaust to prevent damage to the catalytic cell.

Abstract: Improved noise and emission control apparatus for use with an internal combustion engine which include an enclosed cylindrical housing. Mounted in the housing is: noise reduction apparatus, catalytic converter apparatus and heat exchange apparatus. The heat exchange apparatus transfers heat from engine exhaust gases to a fluid passing through the housing.

Abstract: Improved emission control apparatus for use with an internal combustion engine having a housing with an inlet and outlet, the outlet being connected to the exhaust of the engine. Mounted in the housing at spaced locations are first and second catalytic cells through which the engine exhaust gases pass for conversion to less noxious compounds. Some of the gases passing through the first catalytic cell are returned upstream thereof for recirculation through said first catalytic cell. All of the gases pass through the second catalytic cell.