Device for Adjusting a Layer Front

A method of laying a reinforcing ply on a receiving surface of generally cylindrical shape, said ply comprising a front edge and a rear edge which are intended to be butted against each other, after a complete rotation of the receiving surface, between a maximum tolerance (Ts) and a minimum tolerance (Ti) measured relative to a reference source, comprising the steps of:

• producing a ply having a given theoretical length;
• determining the length between the front edge and the rear edge on a central measurement line, and on at least two lateral measurement lines positioned transversely one on each side of the central measurement line;
• laying said ply on a starting belt;
• determining the length correction to be made on the central measurement line so as to ensure that the two tips of an edge of the ply corresponding to the measured lengths whose values are most different from each other (Lmax, Lmin) are placed at equal distances from the reference median line which is located at a distance from the reference edge and which corresponds to the mean value of the maximum tolerance and the minimum tolerance;
• transferring the front edge of the ply to the receiving surface;
• and
• laying the rest of the ply while the longitudinal movement of the starting belt is adjusted relative to the circumferential movement of the receiving surface in such a way that the length laid on the central line is equal to the length measured on said central measurement line corrected by said length correction.