A lubricant for a rolling-element bearing includes a conventional lubricant as a base lubricant and at least one first additive, wherein the first additive includes muscovite, and the lubricant includes a proportion of muscovite that is between 3% and 5%. Also a method of lubricating a rolling-element bearing using the lubricant and a method of repairing a rolling-element bearing using the lubricant.

A method and a device for stopping a magnetic suspension centrifuge includes: a frequency-conversion cabinet connected with the magnetic suspension centrifuge judges a stopping state of the magnetic suspension centrifuge; if the stopping state is judged to satisfy a preset condition, the frequency-conversion cabinet switches a operating mode of a motor of the magnetic suspension centrifuge from an electrically-powered state mode to a power generation state mode, so as to convert the inertia mechanical energy of the motor when the motor stops into electric energy; and the frequency-conversion cabinet leads the electric energy into a power grid, so as to consume the electric energy. Accordingly, the problem that the motor of the magnetic suspension centrifuge cannot be rapidly switched from an operating state to a stopping state when an exception occurs to a bearing or a bearing controller in the prior art can be solved.

A hydrodynamic bearing assembly includes a first member including a first engaging surface. The first member is stationary in a non-operating mode of the bearing assembly and rotates about an axis in an operational mode of the bearing assembly. The first member includes a first bore and a shaft positioned within the first bore and including an end surface. The hydrodynamic bearing assembly also includes a second member including a second bore and a second engaging surface positioned adjacent the first engaging surface. The second member is stationary in both the non-operating mode and the operational mode of the bearing assembly. The hydrodynamic bearing assembly further includes a spacer member positioned within the second bore and is configured to engage the first member to define a first gap between the first engaging surface and the second engaging surface in the non-operational mode.

A turbocharger includes a turbine wheel, a compressor wheel, a shaft coupled to the turbine wheel and the compressor wheel, and a thrust bearing. The thrust bearing includes a loaded side and an unloaded side. The loaded side bears a majority of axial loading caused by force imbalances between the turbine wheel and the compressor wheel during engine startup. The thrust bearing restricts oil flow to the unloaded side as compared to the loaded side during engine startup.

The present application provides a method and a device for stopping a magnetic suspension centrifuge. The method comprises: a frequency-conversion cabinet connected with the magnetic suspension centrifuge judges a stopping state of the magnetic suspension centrifuge; if the stopping state is judged to satisfy a preset condition, the frequency-conversion cabinet switches a operating mode of a motor of the magnetic suspension centrifuge from an electrically-powered state mode to a power generation state mode, so as to convert the inertia mechanical energy of the motor when the motor stops into electric energy; and the frequency-conversion cabinet leads the electric energy into a power grid, so as to consume the electric energy. By means of the method and device for stopping the magnetic suspension centrifuge, the problem that the motor of the magnetic suspension centrifuge cannot be rapidly switched from an operating state to a stopping state when an exception occurs to a bearing or a bearing controller in the prior art can be solved.

Provided is a magnetic bearing device which allows easy initial adjustment and allows optimal bearing control to be performed by a simple algorithm without increasing a memory capacity of a controller. A pair of square multipliers and an adder acquire respective steady-state current values of a pair of electromagnets which attract a rotor shaft of a magnetic bearing not shown in opposite radial directions, square the respective steady-state current values, and add up the respective squared steady-state current values. Then, to optimally change respective currents in the electromagnets in accordance with a mounting posture of the magnetic bearing, a correction coefficient arithmetic operator calculates a correction gain instruction value acting on the electromagnets from the steady-state current values squared/added up. Then, a gain instruction value obtained by adding the correction gain instruction value to a fundamental gain of a control circuit for the electromagnets is input to a gain amplifier. The gain amplifier generates a corrected current instruction value on the basis of the gain instruction value and optimally controls the magnetic bearing.

A method of electrodynamically finishing a plain bearing includes electrically separating a bearing housing from a journal shaft with a lubricant disposed on a bearing surface of the bearing housing. The bearing housing or the bearing housing is rotated relative to the other and a voltage differential applied across the bearing housing and the journal shaft. One or more asperities disposed on the bearing surface are eroded with electric discharge events between the journal shaft and the bearing housing. Electrodynamically finished bearing assemblies and reaction/momentum wheel arrangements having such bearing assemblies are also described.

A lubricant for a rolling-element bearing includes a conventional lubricant as a base lubricant and at least one first additive, wherein the first additive includes muscovite, and the lubricant includes a proportion of muscovite that is between 3% and 5%. Also a method of lubricating a rolling-element bearing using the lubricant and a method of repairing a rolling-element bearing using the lubricant.

A method of electrodynamically finishing a plain bearing includes electrically separating a bearing housing from a journal shaft with a lubricant disposed on a bearing surface of the bearing housing. The bearing housing or the bearing housing is rotated relative to the other and a voltage differential applied across the bearing housing and the journal shaft. One or more asperities disposed on the bearing surface are eroded with electric discharge events between the journal shaft and the bearing housing. Electrodynamically finished bearing assemblies and reaction/momentum wheel arrangements having such bearing assemblies are also described.

A hydrodynamic bearing assembly includes a first member including a first engaging surface. The first member is stationary in a non-operating mode of the bearing assembly and rotates about an axis in an operational mode of the bearing assembly. The first member includes a first bore and a shaft positioned within the first bore and including an end surface. The hydrodynamic bearing assembly also includes a second member including a second bore and a second engaging surface positioned adjacent the first engaging surface. The second member is stationary in both the non-operating mode and the operational mode of the bearing assembly. The hydrodynamic bearing assembly further includes a spacer member positioned within the second bore and is configured to engage the first member to define a first gap between the first engaging surface and the second engaging surface in the non-operational mode.