| 摘要 |
<p>PURPOSE:To reduce DC resistance per turn, and increase efficiency by winding a second coil arranged outside a first coil wound around a main yoke, so as to previously provide a vacant hole in the central part. CONSTITUTION:An inner coil 19 is directly wound around a main yoke 15. Independently of the inner coil 19, an outer coil 20 is formed in the state of regularly wound air-core having a vacant hole 21 in the central part. The inner coil 19 is inserted into the vacant hole 21 of the outer coil 20. In the gap between the inner coil 19 and the outer coil 20, adhesive agent is injected, and both of the coils are fixed. The main yoke 15 is installed on a back faced yoke 18 to which side yokes 16, 17 are fixed. Thereby, a second coil 20 arranged outside the first coil 19 can be regularly wound with a simple means; the DC resistance per turn is reduced, and the efficiency is in increased; the device can be small-sized.</p> |
