PURPOSE: To prevent the yield of voids and the peel-off of thermoplastic resin from the surface of a high voltage transformer, by molding the high voltage transformer with the thermoplastic resin, and further molding the periphery thereof with the same kind of thermoplastic resin.
CONSTITUTION: A high voltage portion 4a of a high voltage transformer 4 with thermoplastic resin 6. As a result, a part of the resin 6 is impregnated into the coils of the high voltage portion 4a and filled in the space between the coil wires. A part of the resin is buried in the gaps between the coils and a core. Furthermore, a part of the resin thinly covers the surface of the coils and core. The transformer that is molded in this way and other parts 5 constitute a high voltage power supply circuit 2, which is installed in a case 1. The space in the case 1 is filled with thermoplastic resin 7 which is of the same kind as the resin 6. At this time, the resins 6 and 7 are locally diffused each other at a boundary portion 8 so as to form one body. In this constitution, voids are not generated, the thermoplastic resin is not peeled off from the surface of the high voltage transformer, and withstanding voltage characteristics are excellent.
KOBAYASHI HISAO
KOMATSU SEIICHIROU
WAKO ELECTRIC