摘要 |
A rotor core (C) for a rotating electrical machine, laminations (10) for such a rotor core, and a method of assembling the rotor core onto a rotatable shaft (60) of the rotating electrical machine. The rotor core (C) comprises a pack of laminations, and patches (12) of sheet or sprayed material are provided on at least one side of a few laminations. The laminations having the patches are regularly spaced through the pack to define blocks (31, 38) of laminations. The patches (12) have a coefficient of friction such that said at least one lamination and an adjacent lamination are able to slide relatively to one another on slip planes S (Figure 7, exaggerated) when the pack of laminations is mounted on the shaft. This allows movement of one to several microns between adjacent blocks (31, 38) of the laminations, so enabling the rotor core to conform to a slight permanent mis-shape of the shaft (60), or alternatively allowing the shaft to return to a normal shape during overspeed testing if it was slightly bent during manufacture. <IMAGE> <IMAGE> |