Rotary cup spinning device provided with drivable rotary cup

Open-end spinning machine with a rotor (1) comprising a rotor disc (4) mounted on a shaft (12) in a radial bearing (5) has a rotor overhang (X), from the front of the disc to the start of the radial bearing, of less than 29 mm. Independent claims are also included for: (1) rotor for an open-end spinning machine, comprising a rotor disc rigidly fixed to a shaft, where the product of the length (Y) of the rotor disc (in mm) and the diameter (D) of the shaft (in mm) is less than 195; (2) roller bearing unit comprising pairs of supporting discs (7, 9; 8, 10) mounted on common shafts (13, 14) in housings, where the journals (21, 23; 22, 24) of each shaft have different diameters.