To eliminate useless space occupied by a secondary core and to make space efficiency to be proper due to increasing the number of secondary coil windings.
An inverter transformer is provided with a primary coil 10 and a secondary coil 20 which are arranged on a same plane and a pair of cores 30 and 40 which forms a closed magnetic route. The primary coil 10 and the secondary coil 20 are electromagnetically junctioned by the pair cores 30 and 40, a project 43 being positioned between the primary coil 10 and the secondary coil 20 is formed on one of the coils at least and the project 43 is made to face the other core 30 apart from a short distance. When let the minimum section square of the primary sides of the cores 30 and 40 be S1 and the electromagnetic coefficient of the primary coil 10 and the secondary coil 20 be K, the minimum section square of the secondary of cores 30 and 40 becomes the value of S1K.
WATANABE SHIGEAKI
NAKANO MINORU
ITO KOJI
