| 摘要 |
<p>This circuit comprises two identical permanent magnets (12-14) which are juxtaposed and joined together by a first flux return yoke (16). The magnets have a continuous face on which a north pole and a south pole appear, which are separated from each other by a line of zero field (26). A second flux return yoke (10) is located opposite the continuous face of the magnets so as to make an airgap (24) with a thickness which is small compared to the other two dimensions. With high-energy magnets, the magnetic field gradient is very high on either side of the line of zero field, and the linear range of this gradient may be relatively large (close to one millimetre). This circuit is to be associated with a field-measurement probe in order to constitute a linear microdisplacement sensor. By using annular magnets, such a sensor makes it possible to measure radial or axial relative displacements of ball bearing raceways. <IMAGE></p> |
