Patent ID: 8246332

Claim:
A rotor, moulded of plastic material, capable of being rotatably mounted into a cavity of a pump body, and having a space extending through a center of the rotor for accommodating one or more vanes therethrough forming pumping members, wherein at least a part of the surfaces thereof, which undergo sliding displacements against a wall of the pumping cavity and the one or more vanes, is covered by at least one metallic foil adhered to the subjacent surface of the plastic material to reduce the resistances to the sliding displacements and to mechanically reinforce the rotor, wherein said metallic foil has a main substantially plane working surface with a diametral portion slightly projecting in correspondence with the space for the one of more vanes, and from which extend some portions bent with respect to the main substantially plane working surface and having a shape to fasten the metallic foil to the rotor, and wherein the metallic foil and the rotor are joined by one of mechanical fastening and means of a co-moulding operation.