ANTI-LOOSENING DEVICE FOR A FASTENING UNIT OF A MOTOR-VEHICLE WHEEL

An anti-loosening device for a fastening unit of a motor-vehicle wheel is configured to be coupled with a wheel hub. The anti-loosening device is configured to be arranged within the wheel hub along an axial direction, so that a main axis of the anti-loosening device coincides with the wheel axis. The anti-loosening device includes a gear arranged to cooperate with inner teeth of the wheel hub, an elastic element extending axially with respect to the gear, and a coupling element obtained on a sector of said gear, arranged to receive a corresponding fastening. During assembly of the wheel—hub assembly, the anti-loosening device is arranged to create a compressed configuration, wherein the gear is decoupled with respect to the inner teeth, and is arranged within a cavity portion obtained on the inner surface of the wheel hub, so as to allow rotation of the anti-loosening device around the main axis.