TRANSFORMER, AND MANUFACTURING METHOD OF CASE THEREOF

摘要

PROBLEM TO BE SOLVED: To provide a transformer of which the heat radiation performance is improved.SOLUTION: A transformer 1 comprises: an input-side primary coil 21; an output-side secondary coil 22; a core 20 around which the primary and secondary coils 21 and 22 are wound; and a casting case 2 for accommodating a transformer body 2 formed of the coils and the core. A gap between the case 3 and the transformer body 2 is filled with a mold resin 4. The case 3 includes: a bottom face part 31 to which the transformer body 2 is mounted; a sidewall part 32 surrounding the bottom face part 31; and an opening 30 which is provided at a position opposing the bottom face part 31 and through which the transformer body 2 is accommodated and filling with the mold resin 4 is performed. A thickness T1 of a mold layer 41 formed in the gap between an inner wall surface 32A of the sidewall part 32 and an outer side face 20C of the transformer body 2 which is proximate to and opposes the inner wall surface, is fixed within a range of a predetermined length L1 from the side of the opening 30 of the case 3 to the bottom face part 31.