Patent ID: 7983044

Claim:
An inverter for an automobile comprising: a metal case providing a fluid path in which cooling water flows; and a semiconductor module fixed to said case; wherein said semiconductor module comprises a plurality of semiconductor elements for converting from DC electric power to AC electric power and a metal base for carrying said plurality of semiconductor elements, wherein said fluid path comprises an inlet, a cooling part, and an outlet, wherein said cooling part of said fluid path has a quadrangle cross-sectional form perpendicular to the flow of cooling water, with a width that is larger than a depth, wherein a fluid path between said inlet and said cooling part has a form that changes so that a depth thereof decreases gradually and a width thereof increases gradually along with the flow of the cooling water, wherein said case forms an opening that connects to said cooling part of said fluid path, wherein said metal base is formed larger than said opening of said case and closes said opening at an outer side of said case, and wherein said case is formed so that, in a direction in alignment with the flow of cooling water, an end part of a top portion of said case is upstream from a termination part of reduction of the depth direction of the fluid path of said case.