Method for braiding reinforcing fibers with variation in the inclination of the braided fibers

A method of braiding a layer of reinforcing fibers on a mandrel (8) using a braiding machine having a ring (9) carrying at least two series of reinforcing fiber reels comprising:

• moving the mandrel longitudinally, along a direction (AX) normal to and defining a central axis of the ring (9), at a predetermined forward speed (Vm1, Vm2, Vm3);
• and
• moving the at least two series of reels along the ring (9) so that they cross while rotating at a predetermined speed of rotation (ωc1, ωc2, ωc3) in opposite directions about the central axis (AX) of the ring;
• wherein the braid is formed on the mandrel (8) in a region of convergence (R) of the reinforcing fibers in a vicinity of which the reinforcing fibers together define a conical shape (C);
• the method further comprising:
• a reconfiguration step in which the movement of the reels is stopped, and in which the machine is rearranged so that an angle (a1, a2, a3) at the apex of the conical shape (C) that is defined by the reinforcing fibers in the vicinity of the region of convergence (R) takes on a new value (a1, a2, a3), and in which the machine is set with a new forward speed (Vm1, Vm2, Vm3) for the mandrel (8) and a new speed of rotation (ωc1, ωc2, ωc3) for the reels;
• and
• a step of restarting the braiding, in which the movement of the reels along the ring (9) and of the advance of the mandrel (8) are re-established using the new forward speed (Vm1, Vm2, Vm3) and the new speed of rotation (ωc1, ωc2, ωc3).