The invention relates to a locking device (300) comprising: a shaft (24) comprising a first thread (22); and a nut (12) and a ring (13) to be assembled on the shaft; the nut comprising a first inner thread (18) defining a first radial clearance with the first thread of the shaft; the nut further comprising a second inner thread (20) in the opposite direction to the first inner thread, the ring (13) comprising a second thread (40) defining a second radial clearance with the second inner thread of the nut; the ring comprising a third inner thread (38) defining a third radial clearance with the first thread of the shaft. The inner threads and the first and second threads have an identical and constant thread pitch; and each of the second and third radial clearances is greater than the first radial clearance.