Being frame structure of the electronic system which possesses the electric part circuit in frame structure

摘要

PROBLEM TO BE SOLVED: To radiate heat while a change of internal pressure is suppressed, to prevent invasion of water vapor and harmful gas from outside, and to prevent an accident due to moisture condensation and corrosion of electric circuit component in a hermetical casing used in an electronic device such as communication equipment.;SOLUTION: The hermetical casing is provided with a main body 1, a cover 2 and a movable fin 7. The movable fin 7 can automatically slide inside and outside the casing in accordance with the change of internal pressure of the hermetical casing with the change of an inner temperature of the hermetical casing. When the inner temperature of the hermetical casing rises by heat generation from the electric circuit component loaded on a package 4 in the hermetical casing, a radiation area of the movable fin 7 can be increased while sealing property is kept. Thus, radiation effect can be improved.;COPYRIGHT: (C)2004,JPO&NCIPI