| 摘要 |
<p>PURPOSE:To lessen a flat transformer in thickness by a method wherein a spiral patterned coil is formed on, at least, either of the upside and underside of a board so as to be located outside a through-hole, and a thin ring-shaped winding coil is inserted into a ring-shaped space between the inner part of a magnetic core and the through-hole. CONSTITUTION:A magnetic core 2 is divisible into an upper piece 3 and a lower piece 4 and formed thin in a vertical direction. The magnetic core 2 is composed of an inner part 2a and outer parts 2b and 2c which are linked together to form a closed magnetic circuit. Furthermore, a board 9 is inserted between the outer parts 2b and 2c of the magnetic core 2, and the inner part 2a is inserted into a through-hole 10 provided to the board 9. A spiral patterned coil 11 is formed on both the front side 9a and the rear side 9b of the board 9 so as to be located outside the through-hole 10. Furthermore, a bobbin-less winding coil 13 is inserted in a ring-shaped space between the inner part 2a and the through-hole 10. By this setup, a transformer of this constitution can be lessened in thickness.</p> |
