Diesel Exhaust System Reversible Particulate Filter

Abstract

The invention concerns a diesel particulate filter in an exhaust system of a vehicle having a diesel engine. The particulate filter may have soot burned out via a regeneration process, and may be serviced for ash buildup by selectively reversing the diesel particulate filter, or its brick, in the exhaust system.

1 . An exhaust system for a vehicle having a diesel engine comprising:
 a diesel particulate filter having a first end and an opposed second end;   a first pipe, located upstream of the diesel particulate filter, for directing exhaust gases into the diesel particulate filter;   a second pipe, located downstream of the diesel particulate filter, for receiving exhaust gases from the diesel particulate filter;   a first mounting flange mounted on the first end of the diesel particulate filter, mountable on either of the first pipe and the second pipe, and mounted on one of the first pipe and the second pipe; and   a second mounting flange mounted on the second end of the diesel particulate filter, mountable on either of the first pipe and the second pipe, and mounted on the other of the first pipe and the second pipe.   
   
   
       2 . The exhaust system of  claim 1  wherein the diesel particulate filter includes a brick that has a wall-flow honeycomb structure. 
   
   
       3 . The exhaust system of  claim 1  including a diesel oxidation converter connected to an upstream end of the first pipe. 
   
   
       4 . The exhaust system of  claim 1  including a muffler connected to a downstream end of the second pipe. 
   
   
       5 . The exhaust system of  claim 1  wherein the diesel particulate filter includes a housing having an inlet channel and a brick mounted in the housing having a first end and an opposed second end, with the brick selectively mountable in the housing in a first orientation with the first end facing the inlet channel and in a second orientation with the second end facing the inlet channel. 
   
   
       6 . The exhaust system of  claim 1  including a controller, an upstream pressure sensor located adjacent to the first pipe and operable to measure an upstream pressure in the exhaust gases, and a downstream pressure sensor located adjacent to the second pipe and operable to measure a downstream pressure in the exhaust gases, with the upstream and downstream pressure sensors in communication with the controller. 
   
   
       7 . The exhaust system of  claim 1  wherein the first mounting flange is removable from one of the first pipe and the second pipe and reinstallable on the other of the first pipe and the second pipe, and the second mounting flange is removable from the other of the first pipe and the second pipe and reinstallable on the one of the first pipe and the second pipe to thereby allow for reversal of the diesel particulate filter in the exhaust system. 
   
   
       8 . The exhaust system of  claim 7  including a controller operable to detect at least one parameter correlating to an ash buildup in the diesel particulate filter and operable to determine a reversal or replacement of the diesel particulate filter is needed. 
   
   
       9 . The exhaust system of  claim 1  including a controller operable to detect at least one parameter correlating to an ash buildup in the diesel particulate filter and operable to determine a reversal or replacement of the diesel particulate filter is needed. 
   
   
       10 . A method of monitoring and servicing a diesel particulate filter that may become loaded with ash, in an exhaust system of a vehicle having a diesel engine, the method comprising the steps of:
 (a) monitoring at least one parameter indicative of a buildup of the ash in the diesel particulate filter;   (b) determining from the at least one parameter if action is required due to the ash buildup in the diesel particulate filter;   (c) indicating that diesel particulate filter servicing is needed when it is determined in step (b) that action is required; and   (d) reversing a direction of exhaust flow through a brick in the diesel particulate filter when step (c) indicates the servicing is needed and if the reversal is desirable.   
   
   
       11 . The method of  claim 10  wherein step (a) is further defined by the at least one parameter including at least vehicle mileage. 
   
   
       12 . The method of  claim 10  wherein step (a) is further defined by the at least one parameter including at least detecting a difference in pressure between an upstream end and a downstream end of the diesel particulate filter. 
   
   
       13 . The method of  claim 10  wherein step (d) is further defined by removing the brick from a housing of the diesel particulate filter and reinstalling the brick in a reverse direction. 
   
   
       14 . The method of  claim 10  wherein step (d) is further defined by removing the diesel particulate filter from the exhaust system, and reinstalling the diesel particulate filter into the exhaust system in an opposite orientation. 
   
   
       15 . The method of  claim 10  wherein step (d) is further defined by the reversal being desirable if the direction of exhaust flow through the brick in the diesel particulate filter has not been previously reversed. 
   
   
       16 . The method of  claim 10  including the step of: (e) replacing the diesel particulate filter in the exhaust system when step (c) indicates that servicing is needed and reversal of the direction of exhaust flow through the brick is not desirable. 
   
   
       17 . The method of  claim 10  wherein step (c) is further defined by the indication that servicing is needed including lighting an indicator light on the vehicle. 
   
   
       18 . A method of regenerating and servicing a diesel particulate filter in an exhaust system of a vehicle having a diesel engine, the method comprising the steps of:
 (a) operating the diesel engine and exhaust system in a normal operating mode;   (b) monitoring at least one soot parameter indicative of soot buildup in the diesel particulate filter while operating in the normal operating mode;   (c) monitoring at least one ash parameter indicative of a buildup of the ash in the diesel particulate filter;   (d) determining from the at least one soot parameter when the diesel particulate filter needs regenerating;   (e) operating the vehicle in a regeneration mode, if it is determined in step (d) that the diesel particulate filter needs regenerating;   (f) determining from the at least one ash parameter if action is required due to the ash buildup in the diesel particulate filter; and   (g) reversing a direction of exhaust flow through a brick in the diesel particulate filter when step (f) determines that action is required.   
   
   
       19 . The method of  claim 18  wherein step (g) is further defined by removing the brick from a housing of the diesel particulate filter and reinstalling the brick in a reverse direction. 
   
   
       20 . The method of  claim 18  wherein step (g) is further defined by removing the diesel particulate filter from the exhaust system, and reinstalling the diesel particulate filter into the exhaust system in an opposite orientation.