Patent ID: 7360414

Claim:
A device for determining at least one parameter of a medium flowing in a conduit in a main flow direction, comprising: a conduit member that forms a conduit passage and includes a center axis running along the conduit passage; a sensor device including a bypass section arranged in the conduit member in such a manner that a partial flow of the medium flowing in the conduit member enters an inlet region of a channel structure formed in the bypass section, wherein: the inlet region includes a separation opening that opens into the conduit passage at at least one of two side walls of the bypass section running parallel to the center axis, and the separation opening is located at a distance from a downstream rear wall of the bypass section in the main flow direction; and a flow guide wall running at least approximately parallel to the side wall provided with the separation opening of the bypass section and being located in the conduit member behind the separation opening, as viewed in the main flow direction, wherein: a length dimension of the flow guide wall, as viewed in the main flow direction, is at least equal to the distance of the separation opening from the downstream rear wall, and a distance of the flow guide wall from the center axis of the conduit member is at least equal to a distance of the side wall provided with the separation opening of the bypass section from the center axis.