Automatic cable tensioning device suitable for parking brakes and parking brake with the automatic tensioning device

Automatic cable tensioning device comprising a support unit (10) coupled to a brake lever (110) of a parking brake (200), a regulating element (20) coupled to the cable, main elastic means (30) acting on the regulating element (20) for regulating cable tension Tc, and a locking assembly (40) coupled to the support unit (10), the locking assembly (40) comprising a ratchet (41) coupled to the regulating element (20) in the movement of the brake lever (110) between a rest position, where relative movement of the regulating element (20) is allowed, and an active position, where relative movement of the regulating element (20) is prevented. The locking assembly (40) comprises a pushing unit (43) locking the ratchet (41) when the brake lever (110) is in the rest position and the cable is not subjected to tension Tc.