Abstract: A device for locking and unlocking a rotor to a stator, at least parallel to the rotation axis of the rotor, includes an annular rotor flange transverse to the axis, an annular stator bearing surface transverse to the axis and at least partly axially facing the annular flange, and a mobile annular bearing surface transverse to the axis and at least partially axially facing the annular flange on the opposite side of the stator annular bearing surface. The mobile annular bearing surface is formed on a thrust ring coupled radially to a stator portion and able to move axially relative thereto. An annular inflatable airbag in the stator portion axially between a stator back and the thrust ring is provided with pneumatic fluid inlet/outlet arrangements.

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: Device for positioning a rotating body movable about an axis in relation to a stator body including a magnetic bearing and a locking/releasing device. The locking/releasing device embodies a plurality of clamps with pads adapted to radially grip a shaft of the rotating body. The clamps are articulated on the stator body about axial pins spaced from the rotational axis and evenly distributed in an angular manner about the rotational axis, and can be pivotally moved about the axis, by a moving control part between a released configuration in which the gripping pads are at a maximum distance from the axis and a locked configuration in which the pads are at a minimum distance from the axis suitable for inducing radial clamping of the shaft.

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.