초록 ▼

Internal combustion engine exhaust gas, passing unreacted through an exhaust gas catalytic or thermal reaction device during the warm-up period of the device, are directed to a rigid conduit that retains the entire flow. The conduit retains the unreacted gas in sequential alignment with a second non

Internal combustion engine exhaust gas, passing unreacted through an exhaust gas catalytic or thermal reaction device during the warm-up period of the device, are directed to a rigid conduit that retains the entire flow. The conduit retains the unreacted gas in sequential alignment with a second non-harmful gas occupying the conduit prior to inflow of the unreacted gas. The second gas blocks flow of the unreacted gas out of the downstream end of the conduit and into the atmosphere. The length and diameter of the conduit minimizes mixing of the unreacted gas and the second gas, and minimizes the volume of the conduit required to retain the unreacted gas. After warm-up of the reaction device, the retained unreacted gas is recirculated to the engine induction system or the reaction device. This approach supplements the emission control of the reaction device by preventing emission of undesirable exhaust gas constituents during starting of the engine and warm-up of the reaction device.

대표청구항 ▼

[ What is claimed is:] [1.] An apparatus for reducing the harmful exhaust gas emissions of an engine having an air intake, an exhaust gas flow stream from the engine, and an exhaust passage for carrying the exhaust gas flow stream from the engine to the atmosphere, wherein a first segment of the exh

[ What is claimed is:] [1.] An apparatus for reducing the harmful exhaust gas emissions of an engine having an air intake, an exhaust gas flow stream from the engine, and an exhaust passage for carrying the exhaust gas flow stream from the engine to the atmosphere, wherein a first segment of the exhaust gas flow stream contains harmful constituents and a second segment of the exhaust gas flow stream contains non-harmful constituents, wherein said first segment is downstream of said second segment, comprising;a conduit having a length, a diameter and a substantially fixed volume, and a third segment of gas having non-harmful constituents occupying said conduit before the inflow of the first segment of exhaust gas containing harmful constituents,one or more valves for preventing said first segment from flowing to the atmosphere and for directing said first segment into said conduit wherein said first segment of the exhaust gas flow stream containing harmful constituents is retained,said conduit having a length and diameter effective for retaining said first segments of said exhaust gas flow stream substantially upstream of said third segment of gas inside of said conduit during inflow of said first segment into said conduit,and means for recycling said first segment of the exhaust gas flow stream containing harmful constituents from said conduit to the engine, wherein said harmful constituents in said first segment of the exhaust gas flow stream are reduced.