Rotary electric machine rotor device

rotor means (4) for rotary electric machine (1) comprising two pole pieces in particular in form of a cylindrical segment (42) to compose a cylindrical rotor device (4) around a magnetic return region. A housing (6) is a permanent magnet (7) provided between the pole pieces (42), of which at least one is held by a strut (43) obliquely to the radial direction in the return flow region (44). This spacer extends from the central radial axis of the pole piece to the magnetic flux return area.