Patent ID: 8670240

Claim:
A board housing case for a vehicle-mounted electronic device, said board housing case being for housing a circuit board which is mounted with a heating component and an external connection connector on a first board surface thereof, said circuit board being hermetically-sealed and held in sandwiched relation in said case that is composed of a metal base and a metal cover, and said circuit board making an end surface of a resin connector housing expose on a side of said case, wherein said base has a material thickness that is a thickness dimension equal to or more than the material thickness of said cover, said base is provided with mounting legs for the purpose of being fixed and installed to a surface to be mounted, and said base is disposed opposite to a second board surface of said circuit board; said cover has a tall flat portion which is disposed opposite to the first board surface of said circuit board and is disposed opposite to said connector housing, and a short flat portion which is disposed opposite to said heating component; said cover and said base have outline peripheral portions coming into contact with each other via sealant, and partial peripheral portions coming into contact with a peripheral portion of said connector housing via said sealant; said heating component is thermally coupled with respect to a heat transfer base portion of said base via a heat transfer mechanism and a small gap portion in which a heat transfer filling material is filled, and said heating component has a coefficient of heat radiation of 0.7 to 1.0; and the short flat portion which is the inner surface of said cover and is disposed opposite to at least said heating component with a gap therebetween is surface-finished to provide a coefficient of heat radiation of 0.7 to 1.0.