Method for producing an encased rotor of a permanent magnet

A method for manufacturing a canned rotor of a permanent magnet motor, in particular a wet-running motor, comprising the steps of:

• providing a shaft with or without a rotor iron part;
• providing a pre-blank that may later form a magnet surrounding said shaft or, if said shaft supports a rotor iron part, surrounding also said rotor iron part;
• said pre-blank having a first end face, a second end face an inside and an outside;
• situating said shaft, said rotor iron part if said shaft supports said rotor iron part, said pre-blank and said metal casing into a pressing tool;
• deforming said pre-blank by applying pressure to said first and second end faces of said pre-blank such that it bears with a non-positive fit on said shaft or said rotor iron part and said outside bears again said inside metal casing, wherein the casing is widened radially by the radially widening pre-blank, until it engages said pressing tool;
• and
• closing the metal casing by situating an annular lid to each of said first and second casing ends, before or after the magnetization and hardening of said pre-blank so that said metal casing is closed by said annular lids, which are tightly connected to the metal casing and the shaft or to the rotor iron part.