Patent ID: 11920660
Assignee: SHANDONG UNIVERSITY
Field: Mechanical elements (Mechanical engineering)
Classification: CPC F | IPC F

Claim 0:
1. A magnetic levitation ball screw pair, comprising:
a working nut, a pre-tightening nut, a screw passing through a screw hole of the working nut and a screw hole of the pre-tightening nut, and balls disposed in raceways provided on an outer wall surface of the screw, an inner wall surface of the working nut, and an inner wall surface of the pre-tightening nut, wherein a plurality of first gaps are defined between the outer wall surface of the screw and the inner wall surface of the working nut, and a plurality of second gaps are defined between the outer wall surface of the screw and the inner wall surface of the pre-tightening nut;
a first adaptive excitation coil group comprising four adaptive excitation coils evenly distributed in a circumferential direction of the screw hole of the working nut, at a first end of the working nut, the four adaptive excitation coils being arranged in two pairs, the adaptive excitation coils of each pair being 180° apart from one another, a magnetic force of each adaptive excitation coil attracting the screw along a radial direction of the screw hole of the working nut and being adjustable;
a first displacement sensor group comprising four displacement sensors, each displacement sensor being arranged at a position corresponding to a respective one of the adaptive excitation coils of the first adaptive excitation coil group, and being positioned for measurement of a respective one of the first gaps;
a second adaptive excitation coil group, comprising four adaptive excitation coils evenly distributed in the circumferential direction of the screw hole of the working nut, at a second end of the working nut, the four adaptive excitation coils being arranged in two pairs, the adaptive excitation coils of each pair being 180° apart from one another, a magnetic force of each adaptive excitation coil attracting the screw along a radial direction of the screw hole of the working nut and being adjustable;
a second displacement sensor group comprising four displacement sensors, each displacement sensor being arranged at a position corresponding to a respective one of the adaptive excitation coils of the second adaptive excitation coil group, and being positioned for measurement of a respective one of the first gaps;
a third adaptive excitation coil group comprising four adaptive excitation coils evenly distributed in a circumferential direction of the screw hole of the pre-tightening nut, at a first end of the pre-tightening nut, the four adaptive excitation coils being arranged in two pairs, the adaptive excitation coils of each pair being 180° apart from one another, a magnetic force of each adaptive excitation coil attracting the screw along a radial direction of the screw hole of the pre-tightening nut and being adjustable;
a third displacement sensor group comprising four displacement sensors, each displacement sensor being arranged at a position corresponding to a respective one of the adaptive excitation coils of the third adaptive excitation coil group, and being positioned for measurement of a respective one of the second gaps;
a fourth adaptive excitation coil group comprising four adaptive excitation coils evenly distributed in the circumferential direction of the screw hole of the pre-tightening nut, at a second end of the pre-tightening nut, the four adaptive excitation coils being arranged in two pairs, the adaptive excitation coils of each pair being 180° apart from one another, a magnetic force of each adaptive excitation coil attracting the screw along a radial direction of the screw hole of the pre-tightening nut and being adjustable;
a fourth displacement sensor group comprising four displacement sensors, each displacement sensor being arranged at a position corresponding to a respective one of the adaptive excitation coils of the fourth adaptive excitation coil group, and being positioned for measurement of a respective one of the second gaps;
a first annular excitation coil fixedly sleeved on an outside of an end of the working nut that faces the pre-tightening nut;
a second annular excitation coil fixedly sleeved on an outside of the first annular excitation coil;
a third annular excitation coil fixedly sleeved on an outside of an end of the pre-tightening nut that faces the working nut; and
a fourth annular excitation coil fixedly sleeved on an outside of the third annular excitation coil.