| abstract |
(57) [Summary] [Purpose] To prevent rainwater from entering the housing installed outdoors and to keep the housing low humidity to prevent condensation. [Structure] A ventilation breathing hole for adjusting the pressure difference between the inside and outside of the housing 8 is provided at the bottom of the housing 8, and a waterproof breathable membrane 3 having water resistance and breathability is provided at the opening of the breathing hole in contact with the outside air, and further waterproof. The air passage of the breathing hole inside the gas permeable membrane 3 is filled with silica gel 4 so that the air flowing into and out of the housing 8 passes through the waterproof gas permeable membrane 3 and the silica gel 4. As a result, the infiltration of rainwater into the housing 8 is prevented by the waterproof gas permeable membrane 3, and the air containing water vapor further passes through the silica gel 4 and is absorbed, so that the inside of the housing 8 is kept at a low humidity and dew condensation can be prevented. |