Patent ID: 6091211
Filing Date: 2000-07-18
Classification: H01J

Abstract:
A mis-convergence correction device comprising:a first controlled coil unit including first and second drum cores and first and second windings, the first drum core having circular flanges at its opposite ends respectively, the second drum core having circular flanges at its opposite ends respectively, the first winding being provided on a portion of the first drum core between its flanges, the second winding being provided on a portion of the second drum core between its flanges, the first and second windings being connected to form a first controlled coil;a second controlled coil unit including third and fourth drum cores and third and fourth windings, the third drum core having circular flanges at its opposite ends respectively, the fourth drum core having circular flanges at its opposite ends respectively, the third winding being provided on a portion of the third drum core between its flanges, the fourth winding being provided on a portion of the fourth drum core between its flanges, the third and fourth windings being connected to form a second controlled coil;a controlling coil unit located between the first and second controlled coil units, the controlling coil unit including a fifth drum core and a controlling coil, the fifth drum core having circular flanges at its opposite ends respectively, the controlling coil being provided on a portion of the fifth drum core between its flanges; anda coil holder accommodating the first and second controlled coil units and the controlling coil unit, the coil holder having first and second halves; the first half having a hold portion for each of the flanges of the first, second, third and fourth drum cores, the hold portion having first and second inclined surfaces non-parallel to each other, the first inclined surface contacting the related flange only at a first point as viewed in a cross-section of the related flange, the second inclined surface contacting the related flange only at a second point as viewed in the cross-section of the related flange, the first and second points being separate from each other; said first and second inclined surfaces and related flanges being positioned so that a straight line perpendicular to the first inclined surface passing through the first point, and a straight line perpendicular to the second inclined surface passing through the second point intersect with each other at a center of the related flange.