| 摘要 |
PURPOSE:To maintain the satisfactory magnetic characteristics between a main magnetic pole and an auxiliary magnetic pole, by having a biased section form of the auxiliary magnetic pole at the winding part of an energizing coil so that the size of said section is increased only in the direction where the magnetic fluxes are easily collected from the main magnetic pole. CONSTITUTION:An auxiliary magnetic pole 20 is set opposite to a main magnetic pole 10 with bias secured at the downstream side of the traveling direction of a recording medium RM. At the same time, a groove D is formed to the pole 20 at the downstream side of the traveling direction of the medium RM and at the position near the center of the pole 10. Therefore the section area of the pole 20 is reduced at least at the winding part of an energizing coil 30 by an amount equal to a counter area of the groove D to the pole 10. As a result, the inductance of the coil 30 is reduced by a due amount. However,the magnetic characteristics have no deterioration at all between both poles 10 and 20. |
