Patent ID: 7572488

Claim:
A method for applying an electrical insulation to a ferromagnetic body of a primary element of an electrical machine, which ferromagnetic body is provided with axial slots for receiving an electrical winding, which axial slots form a Faraday cage whose field-free space can be coated during corona electrostatic spraying, in which the body is coated with electrostatically charged plastic powder, the method comprising applying a powder coating having a layer thickness of between 1.0 and 2.0 mm by means of direct powder spraying onto the body while maintaining a potential difference between the body and the powder, and further characterized in that for the powder spraying, a coarse plastic powder is used, whose powder particles have a mean diameter greater than 150 μm, as a result of which sufficient particles penetrate into the axial slots in order to create a layer, including within the axial slots, of between 1.0 and 2.0 mm.