| 摘要 |
PCT No. PCT/FR87/00447 Sec. 371 Date Aug. 31, 1988 Sec. 102(e) Date Aug. 31, 1988 PCT Filed Nov. 13, 1987 PCT Pub. No. WO88/03459 PCT Pub. Date May 19, 1988.According to the method of machining on ultra-precise surface of revolution (240) on a workpiece (204) held in position by means of a workpiece-carrier spindle assembly (1) whose spindle is mounted on a spindle slide (202) by means of active magnetic bearings, the natural frequencies of the bearing servo-control are adjusted to values which are less than about 80 Hz, and the speed of spindle rotation is adjusted to a value of about 20 Hz to about 75 Hz, the radial and axial positions of the spindle are selectively modified about a nominal position by applying variable reference voltages to the circuits controlling the magnetic bearings, said voltages being varied as a function of control signals which are delivered as a function of the position of the tool (207), and displacement of the spindle slide (202) is inhibited so long as the control signals are less than predetermined values lying within the dynamic range of the magnetic bearings. The invention is particularly suitable for machining atypical surfaces of revolution by copying a master template.
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