Abstract: A brake for a rotary electric machine including a rotor having a shaft, the brake including: at least one fixed armature; at least one yoke that can be moved between a position of braking the shaft of the machine and a position in which the shaft rotates freely; at least one coil borne by the yoke; at least one brake disc borne by the shaft of the rotor; at least one elastic return system for applying the yoke against the brake disc in the absence of electrical excitation of the coil, the armature being positioned such that the excitation of the coil causes the yoke to approach the armature and distances the yoke from the brake disc.