Apparatus for making a yarn comprises two juxtaposed, closely spaced apart suction drums which rotate in the same sense and a delivery duct which protrudes into the triangular space between the suction drums and has an exit adjacent to the suction zones and serves to deliver through said exit singled...http://www.google.es/patents/US4334400?utm_source=gb-gplus-sharePatente US4334400 - Apparatus for making a yarn
