| 摘要 |
PURPOSE:To achieve improved sensitivity in a great deal by moving a magnetic field sensor in the direction of circumference of an electromagnetic converging device and measuring places where magnetic flux density is on the same level, this enabling amplification and detection of non-uniformity only. CONSTITUTION:An electromagnetic converging device that is constituted with coil 4 wound on a bobbin 3 is placed coaxially on a rotating base 5. A magnetic field sensor 6 is placed off the center of the axis and fixed. The output of the sensor 6 is put in a gauss meter 7, so that only deviation can be detected. The output of the gauss meter 7 and the output of a potentiometer 9 that detects rotational speed of the rotating base 5 are input to a XY recorder 8. With this arrangement, in a figure drawn on the XY recorder 8 its abcissa amplifies only a rotated angle of the rotating base 5 and its ordinate only a deviation of the base, allowing inspection of uniformity in the magnetic field with high accuracy. |
