Frequency converter

Abstract

Measures are provided to prevent temperature rise caused by that heat generated from power elements, which is radiated inside a housing. In a housing comprising a radiating section and a cooling fan, a guide is provided on a part of the housing to be made longer a predetermined value than the radiating section. When the cooling fan performs forced cooling through the guide, gases heated by a substrate that generates much heat are prevented from flowing onto a substrate that generates comparatively less heat, to heat the substrate that generates comparatively less heat. Therefore, for example, the substrate that generates much heat is arranged in a position nearer to the cooling fan than the substrate that generates comparatively less heat. Alternatively, the substrate that generates much heat is arranged in a position nearer to the intake face than the substrate that generates comparatively less heat. By providing the guide on the housing, an existing fan can radiate heat from the substrate that generates much heat, the substrate that generates comparatively less heat, etc., thereby enabling reduction in temperature rise.