Patent UA-72701-U (UA)
Title: Method for stabilizing radial position of axis of rotation of shaft of radial spindle bearing on permanent magnets
Inventor: HRYTSENKO VOLODYMYR ILLICH
IPC: B23B19/00
Filed: 2012-02-20
Abstract: A method for stabilizing radial position of the axis of rotation of a shaft of radial spindle bearing on permanent magnets includes measuring the values of gaps between the shaft of radial spindle bearing on permanent magnets and bases of sensors of gap values, definition of unbiased position of the axis of rotation of the shaft spindle bearing on permanent magnets, forming arrays of reference values of gaps, generation of error signals for power magnetic suspensions. The sensors of gap values are installed around the circumference of the inner surface of the housing of radial spindle bearing on permanent magnets in sections along A-A and V-V of a bearing over the magnets of the shaft of spindle bearing on permanent magnets on the axes of coordinate systems XOYand XOYon outer sides of the magnetic power pushers, whose origins lie on the axis of symmetry of the inner surface of bearing housing, control signals are fed to the groups of series-connected power magnetic pushers established in bearing housing in sections B-B and H-H of bearing over magnets of the shaft of spindle bearing on permanent magnets on the axes of coordinate systems and XOYand XOY, whose axes are parallel to each other and parallel to the axes of the coordinate systems XOYand XOY, and under the sensors of gap values installed on the axes of the coordinate system of the same name XOYand XOYare set the equal values of gaps, the symmetry axis of the shaft of spindle bearing on permanent magnets are combined with the origins of coordinate systems XOYand XOY, a symmetry axis of a shaft are taken as a geometrical axis of rotation of the bearing shaft, then are calculated the repulsive force between the magnetic the groups of power magnetic pushers established on the axes of the coordinate system of the same name XOYand XOY, and by magnets of the bearing shaft for a given value of the shift of the bearing shaft on these axes. Then are calculated the stiffness of a radial spindle bearing on permanent magnets and critical angular velocity of a faceplate and bearing shaft. A shaft of spindle radial bearing on permanent magnets is mounted for an angle of rotation, and the values of gaps are measured N times under the sensors of gap values installed on the half-axes +X, +Y, +X, +YHof the coordinate systems XOYand XOYand are asymptotically calculated the unbiased estimates, positions of the geometrical axis of rotation of bearing shaft, where at an angleof rotation of the shaft of bearing the values of gaps under sensors of gap values are equal to measured values is taken as unbiased. A bearing shaft is given the speed of rotation, which satisfies inequalitiesand, at an angleof rotation of a shaft for N times at N revolutions of a shaft are measured the values of gaps under sensors of gap values installed on the half-axes X, +Y, +X, +Yof coordinate systems XOYand XOY, and their asymptotically unbiased estimates are calculated. Then is calculated the value of offset of a geometrical axis of rotation of the shaft under dynamic load in the planes of installation of sensors of gap values on the axes of coordinate systems XOYand XOYand are calculated the values of offset of the geometrical axis of rotation of a shaft and the angles of inclination of the vectors of a dynamic load on the bearing shaft to the axes Xand Xand coordinate systems XOYand XOY. At the angular velocitya bearing shaft is balanced and installed under sensors of gap values mounted on half-axes +X, +Y, +X, +Yof coordinate systems XOYand XOYthe values of gaps that provide at least the rates of differences  and the geometrical axis of rotation of a shaft is approached to its unbiased position or is set in unbiased position, if the rate differences is zero. If the rate of differences is not zero, the angular velocity of rotation of the bearing shaft is increased with a step, at each step of increase of velocity of rotation the bearing shaft is balanced at each step of increasing the angular velocity the bearing shaft is balanced, after balancing shaft at each step of increasing the angular velocity of the shaft at angle of rotationfor times at N revolutions of the shaft are measured the values of gaps under sensors of gap values installed on half-axes +X, +Y, +X, +Yof coordinate systems XOYand XOY, and the rate differences is calculated. If the rate differences approaches zero, the shaft of radial spindle bearing on permanent magnets is balanced with high accuracy. The shaft of a bearing is set in operating speed of rotation, at each discrete angle of rotation of the bearing shaft,, …,, …,for N times at N revolutions of a shaft are measured the gap values under sensors of gap values installed on half-axes +X, +Y, +X, +Yof coordinate systems XOYand XOY, then are calculated their asymptotically unbiased estimates that are taken as the values of reference gaps corresponding to unbiased position of an axis of rotation of the bearing shaft during stabilization of the radial position of the shaft of a spindle bearing on permanent magnets the current values ​​of gaps under sensors of gap values installed on half-axes + XA, + YA, + XV, + YV of coordinate systems XOYand XOYat discrete steps of rotation angle of the bearing, compared with the values of respective reference gaps. In case of deviation of current values of gaps from reference values are generated the error signals to the relevant groups of power magnetic pushers corresponding to the values of deviation of current values of gaps from reference values that prevents the deviation of the axis of rotation of a shaft of spindle bearing on permanent magnets from unbiased position,,,  - asymptotically unbiased estimates of values of gaps under sensors of gap values on half-axes +X, +Y, +X, +Yof coordinate systems XOYand XOYat an angleof rotation of the shaft at;,,,- asymptotically unbiased estimates of the values of gaps under sensors of gap values installed on half-axes +X, +Y, +X, +Yof coordinate systems XOYand XOYat an angleof rotation of the shaft at.