Provided are a vacuum pump, a magnetic bearing device, and a rotor that suppress swinging and vibration of a rotor. A vacuum pump includes, in the following order in the exhaust direction of a gas, the center of gravity of a rotor, an active radial bearing that supports the rotor in the radial direction in a non-contact manner by using a magnetic force, and a passive radial bearing that supports the rotor in the radial direction in a non-contact manner using a magnetic force.

Disclosed are a magnetic bearing, a compressor and an air conditioner. The magnetic bearing includes a radial stator, where the radial stator has a plurality of stator teeth extending inwardly in a radial direction thereof; two axial stators are arranged on two axial sides of the stator teeth, respectively; and radial control coils are wound on the stator teeth, the radial control coil being located outside an area of the stator teeth covered oppositely by the two axial stators. The magnetic bearing, the compressor and the air conditioner can effectively reduce the degree of coupling between a radial electromagnetic control magnetic circuit and an axial electromagnetic control magnetic circuit, and reduce the control difficulty of the magnetic bearing.

A radial magnetic bearing having an inner rotor including a central shaft having a ferromagnetic armature mounted on the shaft and an outer stator providing a plurality of electromagnets including poles made of ferromagnetic material which project radially inwardly towards the rotor is provided. As such, air-gaps (e) are left between end faces of the poles and the ferromagnetic armature, and coils wound around the poles. The poles are extended through outer portions attached to a supporting member. Each pole and the corresponding outer portion are included in an angularly segmented module providing a stack of laminations made of ferromagnetic material. The outer portion defines shoulders with respect to the corresponding pole, the outer portion contacting outer portions of neighboring segmented modules and the outer portions of all segmented modules being assembled by clamping rings, wherein the coils located in free spaces around the poles are mounted in a string.

A magnetic bearing assembly for a rotary machine having a rotor shaft, comprising a stator magnetic circuit secured to a stationary support element and comprising at least one body of ferromagnetic material and at least one coil, both being fitted in a protective annular housing leaving uncovered a surface of revolution of said ferromagnetic body and a surface of revolution of said one coil, the magnetic bearing assembly comprising an annular thrust collar secured to the rotor shaft and radially extending towards the stator magnetic circuit by a radial portion, said radial portion facing the uncovered surfaces of said ferromagnetic body and said one coil. The annular thrust collar comprises at least one flow channel.

A machine learning device learns a control condition for a magnetic bearing device that includes a magnetic bearing having a plurality of electromagnets that apply an electromagnetic force to a shaft. The machine learning device includes a learning unit, a state variable acquisition unit, an evaluation data acquisition unit, and an updating unit. The state variable acquisition unit acquires a state variable including at least one parameter correlating with a position of the shaft. The evaluation data acquisition unit acquires evaluation data including at least one parameter selected from a measured value of the position of the shaft, a target value of the position of the shaft, and a parameter correlating with a deviation from the target value. The updating unit updates a learning state of the learning unit by using the evaluation data. The learning unit learns the control condition in accordance with an output of the updating unit.

A permanent magnet rotor shaft assembly for a high speed electrical machine provides a permanent magnet cylindrical core having a longitudinal axis, the cylindrical core being axially compressed by first and second end shafts and being radially compressed by a sleeve made of a non-magnetic high strength metal. At least one of the first and second end shafts includes, facing the cylindrical core, a central shoulder head that cooperates with a mating central recess made in a central portion of a front face of the cylindrical core. An easy concentric alignment of the first and second end shafts with the permanent magnet cylindrical core is allowed while inserting the sleeve and the stiffness of the assembled set is enhanced.

A bearing arrangement (100) for a spinning rotor shaft (200) of an open-end spinning device, a spinning rotor shaft (200) for such a bearing arrangement (100) and a spinning rotor drive device comprising such a bearing arrangement (100) and such a spinning rotor shaft (200). The bearing arrangement (100) comprises at least one active magnetic radial bearing (110) for the spinning rotor shaft (200) which can be influenced by means of an electronic control system (300). The bearing arrangement is characterized in that the bearing arrangement (100) comprises an active magnetic axial bearing (130) for the spinning rotor shaft (200) which can be influenced by means of the or another electronic control system (300).

A pump includes: a rotor; a magnetic bearing supporting the rotor by a magnetic force; a drive mechanism rotationally driving the rotor; a pump mechanism including an impeller attached to the rotor; and a control unit controlling the magnetic bearing which includes: a bearing rotor member in the rotor formed from a magnetic material; and a bearing stator member facing the bearing rotor member, the bearing stator member has: a core formed from a magnetic material; and a coil wound around the core, the drive mechanism includes: a driven member adjacent in a radial direction to the bearing rotor member; and a drive portion facing the driven member in the radial direction, and magnetically coupled to the driven member to drive the rotor, and the control unit corrects rotational position of the rotor based on a detection signal from a first sensor portion capable of detecting displacement of the rotor.

Non-contact bearing system, such as a magnetic levitation system, having a geometry. The geometry includes a plurality of track elements arranged to nest together in a length direction. The plurality of track elements are shaped to define at least an upper and a lower null flux crossing and the plurality of nested track elements form a conductive metamaterial. Method for constructing a metamaterial null flux magnetic levitation track with tessellating elements of stamped conductors.

A magnetic bearing assembly is for levitating a generally drum-shaped, vertical rotor such that the drum itself is the target of magnetic actuators. The magnetic bearing assembly basically includes at least one active radial actuator configured to center the drum-shaped rotor in an annular air gap so as to enable contactless rotation. The one or more radial actuators are configured to act principally against gravity and is/are located in essentially the same vertical plane as a center of gravity of the drum-shaped rotor.