US Patent 7632110 Electric junction box

A casing 20 surrounding a circuit structure 10 consists of a frame 21, a heat sink 30 located in a rear side of the circuit structure 10 and a cover 60 located in a front side. The frame 21 is in a two-component structure consisting of a first frame member 22 shaped a capital letter C and a second frame member 23 disposed in a rear side of a first terminal part 15A. Thereby, before implementing a switching member 13, the circuit structure 10 can be bonded to the heat sink 30 and, thereafter, the first frame member 22 and the second frame member 23 are separately fixed to the heat sink 30 so that the frame 21 surrounding the circuit structure 10 from the periphery can be completed.