Exhaust gas treatment apparatus with improved pressure pulse damping

Abstract

The invention relates to an apparatus for metering at least one medium for reducing pollutant levels in an exhaust system, in particular for the introduction of fuel into an exhaust tract for regenerating an element for reducing pollutant levels in the exhaust tract. The apparatus includes at least one injection valve, in particular, a pressure-regulated injection valve and at least one supply line for supplying the pollutant-reducing medium to the injection valve. At least one pressure damper is provided in the supply line upstream of the injection valve.

1 - 11 . (canceled) 
     
     
         12 . An apparatus for metering at least one pollutant-reducing medium into an exhaust system, in particular for introducing fuel into an exhaust tract for regenerating an element for reducing pollutant levels in the exhaust tract, including at least one injection valve, in particular a pressure-regulated injection valve, and at least one supply line for supplying the pollutant-reducing medium to the injection valve, wherein at least one pressure damper is provided in the supply line, downstream of the injection valve. 
     
     
         13 . The apparatus as defined by  claim 12 , wherein the pressure damper has at least one porous element received in the supply line. 
     
     
         14 . The apparatus as defined by  claim 13 , wherein the porous element contains at least one of the following materials: a ceramic material; a metal, in particular a sintered metal; a metal alloy, in particular a sintered metal alloy; or a composite material. 
     
     
         15 . The apparatus as defined by  claim 12 , wherein the pressure damper includes at least one hydraulic pressure damper, and the hydraulic pressure damper includes at least one hydraulic volume of the pollutant-reducing medium and at least one energy reservoir that is different from the hydraulic volume and is operatively in communication with the hydraulic volume. 
     
     
         16 . The apparatus as defined by  claim 13 , wherein the pressure damper includes at least one hydraulic pressure damper, and the hydraulic pressure damper includes at least one hydraulic volume of the pollutant-reducing medium and at least one energy reservoir that is different from the hydraulic volume and is operatively in communication with the hydraulic volume. 
     
     
         17 . The apparatus as defined by  claim 14 , wherein the pressure damper includes at least one hydraulic pressure damper, and the hydraulic pressure damper includes at least one hydraulic volume of the pollutant-reducing medium and at least one energy reservoir that is different from the hydraulic volume and is operatively in communication with the hydraulic volume. 
     
     
         18 . The apparatus as defined by  claim 15 , wherein the energy reservoir includes at least one of the following energy reservoirs: an at least partly elastically deformable plastic; a spring element; or a compressible, closed-off fluid volume, in particular a gas volume, in particular air. 
     
     
         19 . The apparatus as defined by  claim 16 , wherein the energy reservoir includes at least one of the following energy reservoirs: an at least partly elastically deformable plastic; a spring element; or a compressible, closed-off fluid volume, in particular a gas volume, in particular air. 
     
     
         20 . The apparatus as defined by  claim 17 , wherein the energy reservoir includes at least one of the following energy reservoirs: an at least partly elastically deformable plastic; a spring element; or a compressible, closed-off fluid volume, in particular a gas volume, in particular air. 
     
     
         21 . The apparatus as defined by  claim 12 , wherein the supply line connects a low-pressure system of a fuel system, in particular a reservoir-type injection system, to the injection valve. 
     
     
         22 . The apparatus as defined by  claim 20 , wherein the supply line connects a low-pressure system of a fuel system, in particular a reservoir-type injection system, to the injection valve. 
     
     
         23 . The apparatus as defined by  claim 12 , wherein at least one metering unit is also received upstream of the injection valve in the supply line, and the metering unit has at least one valve for controlling a procedure of injection of the pollutant-reducing medium. 
     
     
         24 . The apparatus as defined by  claim 22 , wherein at least one metering unit is also received upstream of the injection valve in the supply line, and the metering unit has at least one valve for controlling a procedure of injection of the pollutant-reducing medium. 
     
     
         25 . The apparatus as defined by  claim 23 , wherein the metering unit further includes at least one pressure measuring device, and the pressure damper is disposed upstream of the pressure measuring device. 
     
     
         26 . The apparatus as defined by  claim 24 , wherein the metering unit further includes at least one pressure measuring device, and the pressure damper is disposed upstream of the pressure measuring device. 
     
     
         27 . The apparatus as defined by  claim 25 , wherein the pressure damper is integrated entirely or in part with the metering unit and/or is disposed entirely or in part upstream of the pressure measuring device. 
     
     
         28 . The apparatus as defined by  claim 26 , wherein the pressure damper is integrated entirely or in part with the metering unit and/or is disposed entirely or in part upstream of the pressure measuring device. 
     
     
         29 . The apparatus as defined by  claim 12 , further having at least one overpressure valve, and the overpressure valve is received in a branch line branching off from the supply line upstream of the pressure damper. 
     
     
         30 . The apparatus as defined by  claim 28 , further having at least one overpressure valve, and the overpressure valve is received in a branch line branching off from the supply line upstream of the pressure damper. 
     
     
         31 . The apparatus as defined by  claim 12 , further having at least one damping volume, received in the supply line upstream of the pressure damper, the damping volume including a damping supply of the pollutant-reducing medium.