| 摘要 |
A housing for containing electrical circuit boards 10 has three faces 3, 21 and 24 formed integrally by folding a single metal sheet 26. A fourth face 20 is provided by a separate plate welded to opposite ends of the sheet 26. Each face 3, 21, 24 and 20 has flanges 33, 34, 35, 43, 44, 45 to which side plates 40, 50 are secured. The circuit boards 10 are held in guides 63 on the surfaces of respective plates 60 and 61 which are supported by ledges 56 on unitary frames 50 and 51 secured to respective opposite outer faces 20 and 21 of the housing. Each ledge 56 defines a central aperture 55 that extends across most of the outer face. The opposite outer faces 20 and 21 and the plates 60 and 61 supporting the boards 10 have venting apertures 22, 23, 62 through which cooling gas is supplied to the housing and flows over the circuit boards. <IMAGE> |
