68 can easily pivot with respect to the body 66 independently of one another for preference all the pivoting rings 68 of one and the same roller are the same by way of example they have a thickness in a radial direction of the order of 5 mm and a width substantially identical to that of the fibres advantageously the pivoting rings 68 are closely spaced in the longitudinal direction so as to be able to pivot independently of one another and limit interactions between them according to another feature of the invention the roller comprises means for immobilizing the pivoting rings with respect to the body 66 in the longitudinal direction thus the pivoting rings 68 can only pivot with respect to the body 66 and are incapable of any translational movement with respect to the body 66 in the longitudinal direction this feature makes it possible to achieve the precision with which the fibres are applied and limits the risks of shearing of the pivoting rings which are generally of small thickness there are various conceivable solutions for immobilizing the pivoting rings 68 in the longitudinal direction two alternative forms are illustrated in fig6 and 7 in a first alternative form illustrated in fig6 the body 66 comprises a main body 74 and a sleeve 76 coaxial with the said main body 74 made of a suitable material allowing it to deform when it is not slipped over the main body 74 in operation the main body 74 and the sleeve 76 are immobile relative to one another the inside diameter of the sleeve 76 is equal to the outside diameter of the main body.