Exhaust gas purifying apparatus built-in to a muffler for a diesel engine

An exhaust gas purifying apparatus for a diesel engine, said apparatus comprising:

• a first casing having a first expansion chamber formed therein;
• a second casing having a second expansion chamber formed therein and in series with said first expansion chamber, at least one of said expansion chambers including a separating wall with a plurality of small holes;
• a third casing arranged between said first and second casings to form a passage between said first and second expansion chambers;
• an inlet pipe for introducing an exhaust gas from said engine into said first expansion chamber, said inlet pipe having a predetermined flow direction of exhaust gas, and said first casing and second casing being axially aligned with each other, with said first casing located on the downstream side of said second casing as viewed from said predetermined flow direction, said inlet pipe extending through said second casing to said first casing and opening into said first expansion chamber in said first casing;
• an outlet pipe for discharging the exhaust gas from said second expansion chamber to the outside atmosphere, said outlet pipe extending through said first expansion chamber;
• a filter arranged in said third casing to trap particulates in the exhaust gas flowing therethrough;
• an igniting means arranged adjacent to said filter on the side of said second expansion chamber to burn said particulate matter deposited on said filter, to regenerate said filter;
• and
• a flow control means arranged such that the exhaust gas normally flows from said first expansion chamber through said filter to said second expansion chamber and when said filter is regenerated at least a part of the exhaust gas is introduced from said inlet pipe into said second expansion chamber and flows in reverse from said second expansion chamber through said filter to said first expansion chamber to be discharged therefrom.

An exhaust gas purifying apparatus built-in to a muffler for a diesel engine, said apparatus comprising:

• a first casing having a first expansion chamber formed therein;
• a second casing having a second expansion chamber formed therein and in series with said first expansion chamber;
• a third casing arranged between said first and second casings to form a passage between said first and second expansion chambers;
• an inlet pipe for introducing an exhaust gas from said engine into said first expansion chamber;
• an outlet pipe for discharging the exhaust gas from said second expansion chamber to the outside atmosphere;
• a filter arranged in said third casing to trap particulates in the exhaust gas flowing therethrough;
• an igniting means arranged adjacent to said filter on the side of said second expansion chamber to burn said particulate matter deposited on said filter, to regenerate said filter;
• and
• a flow control means arranged such that the exhaust gas normally flows from said first expansion chamber through said filter to said second expansion chamber and when said filter is regenerated at least a part of the exhaust gas is introduced from said inlet pipe into said second expansion chamber and flows in reverse from said second expansion chamber through said filter to said first expansion chamber to be discharged therefrom;
• said flow control means comprising an inlet bypass conduit connecting said inlet pipe to said second expansion chamber with an inlet control valve arranged therein, an exhaust bypass conduit connecting said first expansion chamber to one of said outlet pipe and the outside atmosphere with an exhaust control valve arranged therein, and a control means for causing said inlet control valve and said exhaust control valve to be normally closed and to be opened when the regeneration of said filter is required;
• whereby said first and second casings constitute a muffler and said exhaust gas purifying apparatus is built-in to said muffler.

An exhaust gas purifying apparatus built-in to a muffler for a diesel engine, said apparatus comprising:

• a first casing having a first expansion chamber formed therein;
• a second casing having a second expansion chamber formed therein and in series with said first expansion chamber;
• a third casing arranged between said first and second casings to form a passage between said first and second expansion chambers;
• an inlet pipe for introducing an exhaust gas from said engine into said first expansion chamber;
• an outlet pipe for discharging the exhaust gas from said second expansion chamber to the outside atmosphere;
• a filter arranged in said third casing to trap particulates in the exhaust gas flowing therethrough;
• an igniting means arranged adjacent to said filter on the side of said second expansion chamber to burn said particulate matter deposited on said filter, to regenerate said filter;
• and
• a flow control means arranged such that the exhaust gas normally flows from said first expansion chamber through said filter to said second expansion chamber and when said filter is regenerated at least a part of the exhaust gas is introduced from said inlet pipe into said second expansion chamber and flows in reverse from said second expansion chamber through said filter to said first expansion chamber to be discharged therefrom;
• said inlet pipe merging with said outlet pipe at a merging point and further extending separately into said first expansion chamber, and said flow control means comprising a control valve arranged at said merging point, said flow control means being movable between a first position in which a communication between said inlet pipe and said outlet pipe is blocked and a second position in which at least a partial communication between said inlet pipe and said outlet pipe is established to cause a reverse flow of the exhaust gas through said filter when a regeneration of said filter is required;
• whereby said first and second casings constitute a muffler and said exhaust gas purifying apparatus is built-in to said muffler.