Patent ID: 7219698

Claim:
A device for generating a mixture of reducing agent and air, comprising: a mixing chamber ( 22 ) into which reducing agent, via a reducing agent supply means, controlled by a metering valve ( 24 ), and air, via an air supply means, can be introduced, the mixing chamber ( 22 ) being embodied in a mixing chamber body ( 20 ) with which a valve body ( 26 ) of the metering valve ( 24 ) communicates; the mixing chamber ( 22 ) discharging toward the metering valve ( 24 ) into a connection stub ( 42 ); and a valve member ( 74 ) in the metering valve ( 24 ) which cooperates at least indirectly with the face end ( 43 ) of the connection stub ( 42 ) as a valve seat for controlling the supply of reducing agent into the mixing chamber ( 22 ); wherein the mixing chamber ( 22 ) is embodied in a bore ( 40 ) in the mixing chamber body ( 20 ) that continues on into the connection stub ( 42 ); further comprising an elastically compressible sleeve ( 66 ) pressed into the bore ( 40 ) in a region remote from the connection stub ( 42 ) and an inlet ( 56 ) for the air discharging at the circumference of the bore ( 40 ); in the region of the sleeve ( 66 ), the sleeve ( 66 ) being compressible by the air that is supplied under pressure, so that air can reach the mixing chamber ( 22 ) through an annular gap formed between the bore ( 40 ) and the sleeve ( 66 ).