The bearing shield has a reshaped axial surface to conduct heat losses from out of the coil winding head and the end lamination zones in order to lowe their temperature. The shield has axial indentations and axial bracings with support fins overlaid with sheet metal ribbing. The profile of the support fins is made narrower than the rib form of the sheet metal ribbing. The latter is sealed by the depressions or elevations on the flange side-carrying the bearing shield termination.