External catalytic converter for small internal combustion engines

A muffler assembly for an exhaust system of an internal combustion engine, comprising:

• a hollow muffler body having an exhaust gas inlet and an exhaust gas outlet;
• a catalytic converter disposed exteriorly of said muffler body for oxidizing and reducing exhaust gas components subsequent to said components being discharged from said exhaust gas outlet, said catalytic converter comprises a hollow housing defining an interior chamber having an upstream opening communicating with said outlet and a downstream opening communicating with atmosphere, and a catalyzer element disposed within said chamber between said upstream and downstream openings;
• a secondary air supply means operable in response to exhaust gas pressure within said catalytic converter housing which permits atmospheric air to flow into the interior of said housing upstream of said catalyzer element;
• and
• mounting means for mounting said catalytic converter on said muffler body at said exhaust gas outlet.

A muffler assembly for an exhaust system of an internal combustion engine, comprising:

• a hollow muffler body having an exhaust gas inlet and an exhaust gas outlet;
• a catalytic converter disposed exteriorly of said muffler body for oxidizing and reducing exhaust gas components subsequent to said components being discharged from said exhaust gas outlet, said catalytic converter comprises a hollow housing having an upstream opening communicating with said exhaust gas outlet and a downstream opening communicating with atmosphere, said hollow housing defining a mixing chamber adjacent said upstream opening and a catalyzer-receiving chamber downstream of said mixing chamber, and a catalyzer element disposed within said catalyzer-receiving chamber;
• an aspirator for drawing secondary air into said mixing chamber to thereby mix with a stream of exhaust gas passing through said catalytic converter housing;
• and
• mounting means for mounting said catalytic converter on said muffler body at said exhaust gas outlet.

A catalytic converter for oxidizing and/or reducing exhaust gas components being discharged from an internal combustion engine, comprising:

• a hollow housing having an upstream inlet opening communicating with a source of exhaust gas and a downstream outlet opening communicating with atmosphere, said hollow housing having a side wall defining a mixing chamber adjacent said inlet opening and a catalyzer-receiving chamber downstream of said mixing chamber;
• a catalyzer element disposed within said catalyzer-receiving chamber;
• an aspirator formed in said housing for drawing air into said mixing chamber to thereby mix with a stream of exhaust gas passing through said housing;
• a mounting member extending from said housing for mounting said housing on an engine component;
• and
• said catalytic converter housing includes a side wall encompassing said mixing chamber, said mounting member is a flange integral with said side wall and together with said side wall forms an L-shaped structure, and said aspirator includes at least one aperture formed at the intersection of said side wall and flange communicating between said mixing chamber and atmosphere.

A catalytic converter for oxidizing and/or reducing exhaust gas components being discharged from an internal combustion engine, comprising:

• a hollow housing having an upstream inlet opening communicating with a source of exhaust gas and a downstream outlet opening communicating with atmosphere, said hollow housing having a side wall defining a mixing chamber adjacent said inlet opening and a catalyzer-receiving chamber downstream of said mixing chamber;
• a catalyzer element disposed within said catalyzer-receiving chamber;
• an aspirator formed in said housing for drawing air into said mixing chamber to thereby mix with a stream of exhaust gas passing through said housing;
• a mounting member extending from said housing for mounting said housing on an engine component;
• and
• said catalytic converter housing includes a side wall encompassing said mixing chamber, said mounting member is a flange integral with said side wall and together with said side wall forms an L-shaped structure, said flange including at least one spacer projecting therefrom, and said aspirator includes at least one aperture formed between said spacer, flange and said side wall communicating between said mixing chamber and atmosphere.