Method and apparatus for an exhaust emissions control system

Abstract

A method for mutual adaptation of a delivery module and a metering module of an exhaust emissions control system that has an exhaust gas conduit and a control module, the delivery module having a reservoir that has a venting valve and contains a uric acid solution that is conveyed via a delivery pump to a pressure regulating valve; and in the metering module, an air stream being compressed with the aid of a pump, conveyed to a pressure accumulator, and conveyed via a regulating valve, together with the uric acid solution, out of the pressure regulating valve to a metering valve, and being conveyed from there to an atomizer unit disposed in the exhaust gas conduit, the value of a reference pressure based on the pressure forming in the exhaust gas conduit being stored in the control module. A method for mutual adaptation of a delivery module and a metering module of an exhaust emissions control system having a control module, a respective parameter or characteristic curve being created for the delivery module and for the metering module and being introduced into the respective module as a machine-readable code. An apparatus for mutual adaptation of a delivery module and metering module for an exhaust emissions control system having an exhaust gas conduit and a control module, the value of a reference pressure based on the pressure forming in the exhaust gas conduit in the context of a calibration cycle being stored in the control module. A mutual adaptation of any arbitrary metering and delivery modules can thereby be implemented in a simple and economical fashion.

1 . A method for mutual adaptation of a delivery module and a metering module of an exhaust emissions control system that has an exhaust gas conduit and a control module, the delivery module having a reservoir that has a venting valve and contains a uric acid solution, the method comprising: 
 conveying the uric acid solution via a delivery pump to a pressure regulating valve;    in the metering module, compressing an air stream by a pump, conveying the compressed air stream to a pressure accumulator, and conveying the compressed air stream via a regulating valve, together with the uric acid solution, out of the pressure regulating valve to a metering valve, and further conveying from the metering valve to an atomizer unit situated in the exhaust gas conduit; and    storing, in the control module, a value of a reference pressure based on a pressure forming in the exhaust gas conduit.    
   
   
       2 . The method according to  claim 1 , wherein upon startup of the exhaust emissions control system, firstly the metering module is activated, the delivery module not being activated.  
   
   
       3 . The method according to  claim 1 , further comprising, in a further step, opening the metering valve and storing the reference pressure in the control module once steady-state pressure conditions have been established.  
   
   
       4 . The method according to  claim 1 , further comprising, upon startup, opening the venting valve, and closing the venting valve again before the metering valve is opened.  
   
   
       5 . The method according to  claim 1 , wherein as operation of the exhaust emissions control system proceeds, the adaptation of the delivery module and the metering module is accomplished at least one of (a) as necessary and (b) cyclically.  
   
   
       6 . An apparatus for mutual adaptation of a delivery module and a metering module for an exhaust emissions control system having an exhaust gas conduit and a control module, the apparatus comprising: 
 means for storing, in the control module, a value of a reference pressure based on a pressure forming in the exhaust gas conduit in the context of a calibration cycle.    
   
   
       7 . The apparatus according to  claim 6 , wherein the control module is implemented in at least one of hardware and software.  
   
   
       8 . A method for mutual adaptation of a delivery module and a metering module of an exhaust emissions control system having a control module, the method comprising: 
 creating one of a respective parameter and characteristic curve for the delivery module and for the metering module; and    introducing the one of the respective parameter and characteristic curve into a respective one of the delivery and metering modules as a machine-readable code.    
   
   
       9 . The method according to  claim 8 , further comprising, upon startup, reading the machine-readable code and storing the code in the control module.