ULTRASOUND FLOW RATE METER

摘要

The invention relates to an ultrasound flow rate meter, which comprises a measuring tube with a straight measuring tube axis, a transmitter for transmitting an acoustic signal onto a first signal path, a receiver for receiving the acoustic signal on the first signal path and a plurality of reflection surfaces on each of which the acoustic signal on the first signal path is reflected at least once. This first signal path is composed of straight subsections wherein: a) the minimum distances of at least three subsections from the measuring tube axis are 0.4-0.6 r, r being the internal radius of the measuring tube; b) a first subsection that defines a first plane parallel to the axis has a directly corresponding second subsection that defines a second plane parallel to the axis, both planes running through a reflection surface and the normal vectors enclosing an angle of less than 10°; c) a third subsection that defines a third plane parallel to the axis has a directly corresponding fourth subsection that defines a fourth plane parallel to the axis, both planes running through a second reflection surface and the normal vectors enclosing an angle of less than 10°; and d) the progression of the signal path describes a polygon in an axial top view, the vertices of which lie inside, on or outside the measuring tube.