A magnetically levitated motor includes a stator, a rotor configured to rotate relative to the stator, and a passive radial magnetic bearing configured to support the rotor relative to the stator in a radial direction. An active longitudinal magnetic bearing is configured to selectively position the rotor relative to the stator in an axial direction.

A pump device (10) includes a housing (30) including a blood inflow port (38) through which blood flows in, and having a fixed-side repulsive magnet (44) disposed in an annular manner; and an impeller (14) that is rotatably housed inside the housing (30), and having a movable-side repulsive magnet (56) disposed in an annular manner. The fixed-side repulsive magnet (44) is disposed in a position offset toward the blood inflow port (38) side relative to the movable-side repulsive magnet (56). In the fixed-side repulsive magnet (44) and the movable-side repulsive magnet (56), a fixed-side repulsive surface (44a) and a movable-side repulsive surface (56a) adjacent to each other have the same polarity.

Novel configurations of levitating passive magnetic bearing configurations are described. Such configurations can be used for the precise control of the magnitude and sign of the bearing stiffness, thereby facilitating the overall design of the system in ways that are not possible with conventional attractive or repelling bearing elements.

A levitating bicycle hub coupling structure using a magnet in the internal contact structure is provided. The levitating bicycle hub coupling structure in which a non-contact type structure in a levitated form is provided to reduce friction enables the position of a hub inner shaft member for transmitting the load of a user to an inner bearing part to be changed to an upper or lower preset position, and fixes the shaft member at a changed position so as to offset the load applied to the shaft member by the repulsive force of the magnets, such that the load is not applied to the bearing parts positioned at both sides of the shaft member or is significantly reduced so as to improve rolling performance, and thus riding of the bicycle becomes smoother and easier.

A blood pump includes a housing having an inlet. A rotor disposed in the housing and configured to rotate substantially about the axis to pump blood from the inlet to the outlet. A stator is disposed within the housing and configured to drive rotation of the rotor about the axis. A bearing mechanism for supporting the rotor inside the housing includes a magnetic bearing configured to magnetically support the rotor inside the housing in a radial direction from the axis. The bearing mechanism includes a sliding bearing configured to physically support the rotor inside the housing in an axial direction along the axis of the housing and allow rotation of the rotor substantially about the axis, the sliding bearing comprising at least one point of contact where the rotor is configured to physically contact a trunnion affixed to the housing.

A magnetic bearing retains a rotatable shaft in a selected position by magnetic coupling between two circularmagnetic assemblies, one of which is connected to the shaft. Each magnetic coupling completes a magnetic circuit. Shaft rotation does not affect the magnetic circuit, but radial displacement of the shaft disrupts the magnetic circuit and increases magnetic reluctance. Increasing magnetic reluctance inhibits radial displacement. The shaft thereby supports a load while rotating freely, constrained to a selected position by forces of magnetic reluctance. A bearing may be employed to maintain gap distance between the magnetic assemblies.

A vacuum pump for rotary driving a rotor by a motor to perform vacuum pumping, wherein a motor rotor of the motor includes a yoke fixed to a shaft of the rotor, and a permanent magnet held at the yoke, and the yoke includes a holding portion provided apart from the shaft and configured to hold the permanent magnet, and a pair of fitting portions provided respectively at both ends of the holding portion in an axial direction and bonded to the shaft by fitting, and a radial thickness dimension of each fitting portion is set less than that of the holding portion.

An arrangement includes a vacuum pump having a rotor, and a drive unit for driving the rotor and having at least one magnetic interference field-generating component and at least one compensation coil for compensating the magnetic interference field generated by the at least one component.

A high-stiffness stabilizer/bearings for passive magnetic bearing systems is provide where the key to its operation resides in the fact that when the frequency of variation of the repelling forces of the periodic magnet array is large compared to the reciprocal of the growth time of the unstable motion, the rotating system will feel only the time-averaged value of the force. When the time-averaged value of the force is radially repelling by the choice of the geometry of the periodic magnet array, the Earnshaw-related unstable hit motion that would occur at zero rotational speed is suppressed when the system is rotating at operating speeds.

A new non-contacting magnetic “snubber” bearing is provided for application to rotating systems such as vehicular electromechanical battery systems subject to frequent accelerations. The design is such that in the equilibrium position the drag force of the snubber is very small (milliwatts). However in a typical case, if the rotor is displaced by as little as 2 millimeters a large restoring force is generated without any physical contact between the stationary and rotating parts of the snubber bearing.