Abstract: A magnetic bearing for active magnetic centering, on at least one centering axis perpendicular to a reference axis, a first body mobile at least on this centering axis relative to a second body includes at least one magnetized member and at least one coil wound around a ferromagnetic core substantially parallel to the reference axis and carried by the second body. Two parallel ferromagnetic plates perpendicular to the reference axis are attached to the core on respective opposite sides of the coil and have transversely oriented edges opposite the airgaps. The core is attached to the edges of the parallel plates.

Abstract: A magnetic actuator, for example a magnetic bearing, embodies a fixed part and a mobile part. These parts are ferromagnetic and form an airgap between them extending parallel to a predetermined first direction. The magnetic actuator further embodies a nonmagnetic wall interposed in the airgap. The wall is that of a confinement chamber, for example. In this magnetic actuator one of the fixed and mobile parts embodies fingers penetrating the nonmagnetic wall and directed towards the other of the fixed and mobile parts.

Abstract: A device for magnetically centering, with respect to a reference axis, a second body mobile relative to a first body includes a magnetic bearing that is active along the reference axis. It further includes two magnetic centering devices offset axially along that axis, on opposite sides of the magnetic bearing.

Abstract: A magnetic bearing for magnetic centering of a rotor relative to a stator relative to two radial centering axes includes actuators operating relative to centering axes and speed sensors having sensing axes coplanar with the centering axes. The rotor includes a ring partly defining the airgaps of the actuators and the sensors.

Abstract: A torque embodying an armature placed radially between a central bar and an external ferromagnetic tubular portion. The central bar is composed of two portions of the same cylinder diametrically opposite each other and having substantially equal angular amplitudes below 180.degree. and separated by generally parallel longitudinal flats. A radial permanent bar magnet is incorporated in the central bar between the cylinder portions. The armature has a winding formed from longitudinal strands connected by transverse strands and arranged into bundles within which all currents flow in the same direction at all times.

Abstract: A polyphase electric motor including a body mobile relative to a fixed body, one of these bodies carrying an exciter strip formed by a plurality of alternating coil windings aligned with each other and connected to an energizer device including a switch adapted to excite the pluralities of coils alternately, the other body comprising a row of alternating magnets and, one on each side of this row, two magnetic bars determining along the row an airgap of constant width in which the exciter strip is disposed. The permanently magnetized row is disposed parallel to the magnetization directions of the magnets constituting it between two continuous magnetic plates.

Abstract: A magnetic bearing secures active magnetic centering with respect to at least one centering axis of a body movable relative to another a static body. It comprises, on each side of a plane of symmetry perpendicular to the centering axis and containing a reference axis: at least one permanent magnet magnetized parallel to the reference axis, at least one combination comprising a coil wound on a ferromagnetic core disposed to procure a magnetic flux parallel to the reference axis and ferromagnetic members adapted to provide a closed magnetic path for magnetic flux produced by the magnet and the coil via airgaps on the centering axis separating the movable body from the body body. A control circuit comprises a sensor responsive to relative movement between the movable body and the body body along the centering axis and adapted to feed to the coil a current adapted to correct any such relative movement. Two ferromagnetic plates carried by the body body have the magnet and the core clamped between them.