Ball or roller bearing-journalled large electric motor

摘要

In a ball or roller bearing-journalled large electric motor for vehicle engines, locomotive wheel sets, machine tools and the like, with an electrically insulating layer in the path of any undesired current flow to earth or within the motor, the electrically insulating layer (7, 9, 18) is applied by plasma or flame spraying onto the unhardened surfaces (6, 8) of the motor in the region of the ball or roller bearing (5) and/or in the region of clutch elements (14) between the motor shaft (3) and an adjacent drive mechanism (17). Also claimed is a method of applying an insulating layer for the above electric motor, in which the shaft (3) is roughened (e.g. sand blasted) in the ball bearing seat region (6), the oxide-ceramic layer is applied by plasma or flame spraying, an epoxide resin is infiltrated into the layer and cured, and then the shaft is ground to size.