Patent ID: 7431573

Claim:
An apparatus for generating a mixture of reducing agent and air, comprising a feed pump ( 16 ) by which reducing agent is pumped and which has a pump housing ( 22 , 32 ), and a mixing chamber ( 50 ), in which reducing agent and air pumped by the feed pump ( 16 ) can be introduced, the mixing chamber ( 50 ) being embodied in a mixing chamber body ( 36 ), the mixing chamber body ( 36 ) communicating with the pump housing ( 22 , 32 ) of the feed pump ( 16 ), wherein the mixing chamber ( 50 ) is embodied in a bore ( 52 ) of the mixing chamber body ( 36 ); wherein an elastically compressible sleeve ( 54 ) is pressed into the bore ( 52 ); and wherein an air inlet ( 56 ) discharges into the bore ( 52 ) at the circumference of the sleeve ( 54 ), the sleeve ( 54 ) being elastically compressible by the air, supplied under pressure, so that air can reach the mixing chamber ( 50 ) through an annular gap ( 55 ) forming between the bore ( 52 ) and the sleeve ( 54 ).