Abstract: There is disclosed a yarn traverse mechanism comprising means for positively feeding yarn at a uniform speed to a yarn traverse arm, and means for moving the yarn traverse arm to and fro to lay the yarn on a tapered bobbin to form a package, said arm moving means comprising a cam shaped to vary the axial movement of the arm in relation to the axial position of the arm in relation to the cam and thus to the diameter of the bobbin to maintain the tension of yarn laid on the bobbin substantially uniform. The cam is a scroll cam.

Abstract: An apparatus for collecting a coreless coiled thread package having a central hollow bore, comprises a thread collecting or receiving disc which presents a central through bore, and a vertical guide column which engages the said bore of the receiving disc, in such a manner that the said disc is displaceable upwardly and downwardly along the said column. The guide column is constructed as a tubular hollow structure, and inside the said hollow structure there are arranged the means for elastically urging upwardly a carriage which is vertically displaceable along the column and carries the said receiving disc. The receiving disc is fitted in a removable, but nonrotatable, manner on the carriage, which, in turn, is not rotatable about the guide column.