Patent ID: RE40759

Claim:
A spinning rotor for open-end spinning machines, comprising: (a) a rotor cup having, (i) an annular wall portion defining a rotor opening, (ii) a bottom wall portion merging with the annular wall portion to define at the merger thereof a maximum exterior diameter of the rotor cup and in the interior thereof a rotor groove, the wall thickness at the maximum exterior diameter of the rotor cup at the merger of the bottom and annular wall portions being between about 0.3 mm and less than 1.0 mm, and less than a wall thickness of the annular wall, and (iii) a mounting hub extending exteriorly from the bottom wall portion, the cross-sectional thickness of the bottom wall portion increasing from the rotor groove to the mounting hub; and (b) a rotor shaft affixed to the mounting hub coaxially with the rotor cup.