Method of winding yarns to form frustoconical yarn packages

A method of winding a yarn in a plurality of superposed layers onto a cylindrical support having a longitudinal axis and fastened around a spindle driven in a rotational movement, in which the yarn is wound by running over a yarn guide which moves in a backward and forward motion (M) parallel to the longitudinal axis of the support and is controlled so as to form a bobbin having a shape with two frustoconical ends, said bobbin comprising a base cone having a first generatrix inclined at a first acute angle to the longitudinal axis and an unwind cone having a second generatrix inclined at a second acute angle to the longitudinal axis, and a main body which joins the two frustoconical ends and has a frustoconical shape, said main body comprising a third generatrix, a first end section which forms a base of the base cone, and a second end section which forms a base of the unwind cone, wherein a diameter of said base of the base cone is different than a diameter of the base of the unwind cone, said method of winding a yarn comprising,

• governing the movement of the yarn guide with a first rule for forming a part of the base cone wherein a last layer of yarn deposited according to said first rule going as far as the end of the unwind cone, and a second rule for terminating the base cone while forming the main body and the unwind cone, wherein a first layer of yarn deposited according to the second rule is parallel to a last layer of yarn deposited according to the first rule, wherein the first acute angle of inclination of the first generatix of the base cone is between 40° and 75°, and, wherein the yarn has a waviness to allow two coils with two superposed layers to intersect at a crossover angle.