Weft injector for air jet loom - has main and sec. air flows into mixing tube with specified divergence for constant flow velocity

摘要

The arrangement is intended for injecting a weft thread into the warp gap of a weaving loom by means of a sub-sonic (supersonic in an alternative arrangement) flow of pressurised transport gas. The injector comprises a chamber (5) connected to the transport air supply (16) and to a first duct (8,7), a second duct (2) through which the thread passes together with a secondary air flow, and a third duct (10) in which the two air flows combine to pass the thread to the nozzle end. The ratio of cross-sectional flow area of the duct (10) to the mass flow rate increases in the flow direction such that at any point along the length of the duct (10) the redn. in air density due to friction losses is at least largely compensated by the increased cross-section. Used as pneumatic weft thread injector for air jet weaving loom.