Mixer for an exhaust system

A mixer for an exhaust system of an internal combustion engine for mixing a reactant with an exhaust gas flow, the mixer comprising:

• a plurality of guide blade portions;
• fold webs, the guide blade portions being provided as guide blade pairs comprising a first blade portion connected to a second guide blade portion by at least one of the fold webs and folded at the at least one of the fold webs such that the first blade portion is disposed extending adjacent to and spaced from the second guide blade portion;
• and
• spacer webs, each of the guide blade pairs being connected to at least one adjacent guide blade pair by at least one of the spacer webs, wherein the fold webs are disposed centrally and located adjacent to each other in an annular pattern of adjacent fold webs and the spacer webs are disposed peripherally spaced apart from each other about a circumference of the mixer, wherein:
• the guide blade portions, the fold webs and the spacer webs are formed from a single integral flat blank;
• the guide blade pairs, comprising the first blade portion connected to the second guide blade portion by the at least one of the fold webs, are separated from adjacent guide blade pairs by one of the spacer webs;
• each of the guide blade portions has a trailing edge axially spaced from a leading edge;
• and
• each of the guide blade portions is connected to another of the guide blade portions of a guide blade pair by two fold webs with a leading fold web adjacent to the leading edge and a trailing fold web adjacent to the trailing edge.

A reactant feeding device for an exhaust system of an internal combustion engine, the reactant feeding device comprising:

• a pipe arrangement for guiding an exhaust gas flow;
• an injector arranged at the pipe arrangement for generating a spray jet from reactant for introduction of the reactant into the exhaust gas flow;
• and
• a mixer arranged in the pipe arrangement downstream of the injector in relation of the exhaust gas flow, the mixer comprising:
• a plurality of guide blade portions;
• fold webs, the guide blade portions being provided as guide blade pairs comprising a first blade portion connected to a second guide blade portion by at least one of the fold webs and folded at the at least one of the fold webs such that the first blade portion is disposed extending adjacent to the second guide blade portion;
• and
• spacer webs, each of the guide blade pairs being connected to at least one adjacent guide blade pair by at least one of the spacer webs, wherein the fold webs are disposed centrally and located adjacent to each other in an annular pattern of adjacent fold webs and the spacer webs are disposed peripherally spaced apart from each other about a circumference of the mixer, wherein:
• the guide blade portions, the fold webs and the spacer webs are formed from a single integral flat blank;
• and
• the guide blade pairs, comprising the first blade portion connected to the second guide blade portion by the at least one of the fold webs, are separated from adjacent guide blade pairs by one of the spacer webs;
• the spacer webs are connected to one of the first blade portions of one guide blade pair adjacent to the leading edge thereof and are connected to one of the second blade portions of another guide blade pair adjacent to the leading edge thereof;
• and
• the spacer webs form an outer peripheral pipe contact surface for engaging an inner surface of an exhaust pipe.