To simplify assembly work and improve productivity in a non- excitation actuated brake in which generation of unpleasant noise originating in the vibration of a brake disc is prevented.

An elastically deformable resilient piece 9 which is formed integrally in cantilever support shape and has a free end protruding in the central bore 7c is provided in the periphery of the central bore 7c of a disc body 7a made of synthetic resin material. As for brake disk 7 fitted on the outer periphery of a hub 10, vibration in an idle-running is prevented by elastic restoration power of the resilient piece 9.