Patent ID: 8274351

Claim:
A transformer device comprising: an iron core; a plurality of coils wound onto said iron core and stacked with each other; a plurality of base members arranged corresponding to said plurality of coils, respectively; a plurality of flow channel member groups provided for said plurality of base members, respectively, and each forming a flow channel directed to a flow of an insulating fluid between a corresponding base member and a corresponding coil; and an obstruction member arranged to obstruct the flow of said insulating fluid such that at least one of the flow channels formed by said plurality of flow channel member groups differs in a flow volume of said insulating fluid from another of said flow channels, and to obstruct the flow of said insulating fluid at a region not overlapping with said iron core in a flowing direction of said insulating fluid among regions of said at least one of the flow channels, wherein said channel flow member group includes a plurality of first flow channel members of a rectangular shape, provided extensively at an inlet side and outlet side of said flow channels, each having two long sides along the flowing direction of said insulating fluid, and two shorter sides substantially perpendicular to the flowing direction of said insulating fluid, and a plurality of second flow channel members of a rectangular shape, provided extensively between the inlet side and outlet side of said flow channels, each having two long sides substantially perpendicular to the flowing direction of said insulating fluid and two shorter sides along the flowing direction of said insulating fluid, and said obstruction member provided at least one of the inlet side and outlet side of said flow channels, and having a portion in a direction substantially perpendicular to the flowing direction of said insulating fluid longer than a length of the two shorter sides of said first flow channel member.