US Patent 7353575 Method and device for producing a fancy knotted yarn

The invention relates to a method and a device for producing a fancy knotted yarn. The treatment air is injected into the yarn channel as primary air via a main bore hole, and as secondary air preferably via two auxiliary bore holes. The introduction of primary air is designed to create a double air vortex, and the introduction of secondary air is designed to ensure the yarn transport and to stabilise the air flow in the yarn channel. The novel solution has surprising advantages in terms of a plurality of quality criteria, predominantly shorter opening lengths, a more uniform vorticity, a number of knots which is higher by approximately 10%, and the possibility of using coarser titers.