Device for injecting aqueous additives in a motor vehicle exhaust pipe

Abstract

This invention relates to a device for injecting aqueous additives into an exhaust pipe of a motor vehicle, including an additive tank and a pumping module for taking the additive and directing it toward the exhaust pipe, characterized in that the pumping module includes a rotary electric pump ( 120 ) and includes a thermally conductive part ( 170 ) in contact with the casing of the pump ( 120 ) and the outlet of a pressure regulator ( 150 ) so as to transfer heat to said outlet of the pressure regulator ( 150 ).

1 . Device for injecting aqueous additives into an exhaust pipe of a motor vehicle, including an additive tank and a pumping module for taking the additive and directing it toward the exhaust pipe, characterized in that the pumping module includes a rotary electric pump ( 120 ) and includes a thermally conductive part ( 170 ) in contact with a casing of the pump ( 120 ) and an outlet of a pressure regulator ( 150 ) so as to transfer heat to said outlet of the pressure regulator ( 150 ). 
     
     
         2 . Device according to  claim 1 , characterized in that the part ( 170 ) in contact with the casing of the pump ( 120 ) and the outlet of the pressure regulator ( 150 ) in order to transfer heat to said outlet of the pressure regulator ( 150 ) is a thermally conductive part. 
     
     
         3 . Device according to  claim 2 , characterized in that the thermally conductive part ( 170 ) is in contact with a pump casing portion ( 120 ) surrounding an electrical control part ( 122 ). 
     
     
         4 . Device according to  claim 2 , characterized in that the thermally conductive part ( 170 ) is a longitudinally cracked tube. 
     
     
         5 . Device according to  claim 2 , characterized in that the thermally conductive part ( 170 ) is a multilobar tube. 
     
     
         6 . Device according to  claim 1 , characterized in that the outlet conduit ( 160 ) of the pressure regulator ( 150 ) is formed by a plastic end piece ( 162 ) in contact with the part ( 170 ) ensuring the transfer of heat from the pump casing ( 120 ). 
     
     
         7 . Device according to  claim 6 , characterized in that the outlet conduit ( 160 ) of the pressure regulator ( 150 ) is integral, with a base ( 110 ). 
     
     
         8 . Device according to  claim 6 , characterized in that the outlet conduit ( 160 ) of the pressure regulator ( 150 ) has a thermally conductive tubular insert ( 164 ). 
     
     
         9 . Device according to  claim 1 , characterized in that the outlet conduit ( 160 ) of the pressure regulator ( 150 ) is in contact with a vertical metal tube ( 166 ) that is connected to a top portion ( 202 ) of a heater ( 200 ) associated with a suction filter ( 210 ) placed at an inlet of the pump ( 120 ). 
     
     
         10 . Device according to  claim 1 , characterized in that the additive is a urea solution. 
     
     
         11 . Device according to  claim 1 , characterized in that the pump is a two-part pump including an electrical control part and a mechanical pumping part, which are magnetically coupled. 
     
     
         12 . Device according to  claim 1 , characterized in that the pump ( 120 ) includes an electrical control part ( 122 ) with an external stator capable of generating a rotary field. 
     
     
         13 . Device according to  claim 1 , characterized in that the thermally conductive part ( 170 ) is made of brass. 
     
     
         14 . Device according to  claim 1 , characterized in that the thermally conductive part is in contact with a mechanical pumping part of the pump ( 130 ). 
     
     
         15 . Device according to  claim 1 , characterized in that it includes timed means suitable for ensuring control of the electrical power supply of the engine when the vehicle is started so as to heat a winding of the motor ( 120 ) without rotating the pump when a measured temperature of the additive indicates a value close to the solidification temperature.