Unitary hybrid exhaust system and method for reducing particulate emmissions from internal combustion engines

A unitary system for removing particulate matter from exhaust gas of an internal combustion engine comprising;

• a housing having an inlet portion and an outlet portion;
• a main flow passage and a by-pass flow passage extending from said inlet portion to said outlet portion for conducting said exhaust gas through said housing;
• valve means for directing said exhaust gas through one of said passages;
• filtering means positioned in said main flow passage for filtering said particulate matter from said exhaust gas;
• regeneration means positioned intermediate said valve means and said filtering means in said main flow passage for selectively regenerating said filtering means by removing said particulate matter therefrom;
• an oxidation means positioned downstream of said filtering means within both said main flow passage and said by-pass flow passage for further oxidizing said particulate matter;
• and
• a control means for controlling the flow of said exhaust gas, selectively activating said regeneration means upon sensing of a predetermined condition and for deactivating said regeneration means upon completion of the regeneration of said filtering means.

A method of removing particulate matter from the exhaust gas of an internal combustion engine comprising the steps of:

• a) providing a main flow passage and a by-pass flow passage within a unitary housing for conducting said exhaust gas from an inlet portion to an outlet portion of said unitary housing;
• b) providing a regeneration means, a filtering means and an oxidation means within said main flow passage of said unitary housing;
• c) conducting said exhaust gas initially through said filtering means to filter said particulate matter, and then through said oxidation means to further oxidize said particulate matter;
• d) periodically directing said exhaust gas through said by-pass flow passage and through said oxidation means;
• e) regenerating said filtering means while said exhaust gas is directed through said by-pass flow passage;
• and
• f) redirecting said exhaust gas through said main flow passage upon completion of said regenerating step.

A unitary system for removing particulate matter from exhaust gas of an internal combustion engine comprising;

• a housing having an inlet portion and an outlet portion;
• a main flow passage and a by-pass flow passage each extending from said inlet portion to said outlet portion within said housing for conducting said exhaust gas through said housing;
• valve means for directing said exhaust gas through one of said passages;
• filtering means positioned in said main flow passage for filtering said particulate matter from said exhaust gas;
• a sound attenuation means positioned within said housing for attenuating sound generated by combustion gases;
• regeneration means positioned intermediate said valve means and said filtering means in said main flow passage for selectively regenerating said filtering means by removing said particulate matter therefrom;
• and
• a control means for selectively positioning said valve means to direct the flow of said exhaust gas through one of said main flow passage and said by-pass flow passage while prohibiting the flow of exhaust gas through the other of said main flow passage and said by-pass flow passage.

A system for removing particulate matter from exhaust gas of an internal combustion engine, said system comprising:

• a) a main flow passage and a by-pass flow passage for conducting said exhaust gas from an inlet portion to an outlet portion of said system;
• b) valve means for selectively directing said exhaust gas through one of said passages;
• c) filtering means for filtering said exhaust gas directed through said main flow passage;
• d) regeneration means positioned intermediate said valve means and said filtering means for selectively regenerating said filtering means by removing said particulate matter therefrom;
• e) an oxidation means positioned downstream of said filtering means in both said main flow passage and said by-pass flow passage for further oxidizing said particulate matter;
• f) a muffler positioned within said by-pass flow passage and intermediate said valve means and said oxidation means;
• and
• g) a control means for controlling the flow of said exhaust gas, selectively activating said regeneration means upon sensing of a predetermined condition, and deactivating said regeneration means when the regeneration process has been completed.