摘要 |
Electronic components such as a control unit for controlling operation of an internal combustion engine are contained in a waterproof casing. The casing is composed of a base and a cover, both connected to each other water-tightly. A respiration filter for establishing air communication between an inside and an outside of the casing is mounted on a mounting surface formed on an outer surface of the cover. The mounting surface is elevated from the outer surface of the cover, and has a plane facing a flange of the respiration filter. The plane is small relative to a height of a respiration hole of the respiration filter. Since the plane on the mounting surface facing the flange of the respiration filter is small relative to the height of the respiration hole, the respiration hole is prevented from being blocked with water staying on the mounting hole due to its surface tension.
|