| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an electromagnetic induction device which uses a bobbin, having a variable winding width and can be reduced in height by suppressing increase in a mounting area, when the device is mounted on a wiring board. SOLUTION: The leg section 4b of a core 4 is inserted into a center hole 9 of a bobbin B9 around which a primary winding 11 and a secondary winding 21 are wound into a state, where the windings 11 and 21 are separated from each other in the axial direction. The bobbin B is divided in the axial direction into a first bobbin piece 1, on which a primary-side winding groove 10 is formed for winding the primary winding 11 and a second bobbin piece 2 on which a secondary-side winding groove 20, is formed for winding the secondary winding 21, the pieces 1 and 2 are connected with each other, and the width of the groove 20 for winding the secondary winding 20 is changed.</p> |
