Blowing nozzle for supporting a weft thread in a weaving machine

Blowing nozzle for supporting a weft thread in a weaving machine, said nozzle including a flow-through canalisation for a fluid flowing into the environment via at least one outlet opening;

• a jet pipe formed in the flow-through canalisation, wherein the flow-through canalisation narrows from a part preceding the narrowest section up to the narrowest section of the jet pipe, namely a critical section;
• and wherein the flow-through canalisation widens from the critical section up to the outlet opening;
• and in that the part of the flow-through canalisation which extends from the critical section up to the outlet opening has an upper wall which is made exclusively concave, and has a lower wall which first has a convex curve from the critical section and then a straight or almost straight section.

Blowing nozzle for supporting a weft thread in a weaving machine, said nozzle provided with a flow-through canalisation for a fluid flowing into the environment via at least one outlet opening, wherein the flow-through canalisation has at least one duct in which is integrated a jet pipe, and wherein said at least one duct has a rectangular section at least at the respective jet pipe.