Hitachi, Ltd.

Hitachi Communication Technologies, Ltd.

Hiroshi Kuwaki

Koji Hata

Yasushi Kimura

Shinya Hamagishi

Seiji Asai

Tadahiro Yamaguchi

Hiroaki Nakashima

Takashi Funada

Osamu Matsubara

Takeshi Kiyose

Yoshihiro Yano

Susumu Miyagawa

Electronic equipment installed outdoors to house an internal unit is provided, meeting the waterproof standard and having an easily replaceable structure of the internal unit. The electronic equipment has an enclosure having a cover and a case with an opening and an air vent, and an internal unit in which an electronic component is mounted. The internal unit has a heat sink and radiation fins for releasing heat generated by the electronic component. The fins are inserted into the opening. The heat sink has a draining portion formed below the fins in a direction perpendicular to an extending direction of the radiation fins, a groove for waterproofing around the fins except an upper portion thereof, and two protrusions for fitting above the fins. The case has a rib for waterproofing around the opening except an upper portion thereof, and two holes for fitting above the opening.

Electronic equipment

In order to ensure waterproofing between a resin enclosure case and a heat sink, a canopy structure is provided in a portion, in which water is likely to penetrate, so as to prevent the water from entering the portion, thereby directing the water flow to the outside of the enclosure. This makes it easy to install and remove an electronic unit, so that an electronic component integrally formed with the heat sink can be easily replaced.

In an electronic apparatus in which plural substrates are arranged in a perpendicular direction between plural cooling fans in a lower part of a case and plural temperature sensors in an upper part of the case, any temperature variation by 2&#xb0; C. in three seconds detected by any one of the temperature sensors is determined to be abnormal, and thermal energy is caused to be discharged from surfaces of substrates on two sides of a flame by raising air flow rates of fans. Expansion of the flame to other substrates is thereby prevented.

Electronic apparatus

Optical transmission equipment

Growing community of inventors

Fujisawa, Japan

Hiroshi Kuwaki