| 摘要 |
PURPOSE:To attain low cost by constituting an area opposite to a gap so as to be smaller than the section of a core substantially orthogonal to the magnetic flux of a magnetic path forming circuit, providing a slant face in a coil side face to the gap and contracting the magnetic flux. CONSTITUTION:When the area opposite to the gap of the cores 1, 2 is defined to be S1 and the sectional area of the core part of a magnetic forming circuit orthogonal with the magnetic flux of the gap opposite part to be S2, S1<S2 is obtained. When the magnetic flux excited by the coil 4 has not convex part 11', a magnetic flux convergence substantially corresponding to Cw'/Cw is attained from the rear core part 12 of a core width Cw to the front core part 11 of a core width Cw'. When it has the convex part 11', the inclination 11'd of the gap 11'e0 of the convex part is spread to a lower core spreading core part 13a, so that the magnetic flux flows correspondingly to the lower core spreading angle theta2 and the inclination angle theta1 of the slant face. Thereby, the complete magnetic flux contraction is realized in the vicinity of the gap. |
