| 摘要 |
<p>A buoyancy body which is intended to float in water in a predetermined attitude and which comprises an inflatable enclosure, a source of gas under pressure such as a gas cylinder, and device for releasing gas from the source into the enclosure to inflate the body if the buoyancy body is immersed in water. A mechanism is provided which releases gas from the source if water enters a chamber. An aperture is provided in a wall of the chamber if the aperture is open and the chamber is immersed in water. A valve is provided to block the aperture unless the pressure outside the chamber exceeds the pressure within the chamber to a predetermined extent. The chamber is mounted on a portion of the body which is immersed in water when the body floats in the predetermined attitude. The chamber communicates with an expansion enclosure which is outside the inflatable enclosure, which is exposed to the environment outside the inflatable enclosure, and at least in part is located at a position remote from the chamber and above the chamber when the body floats in the predetermined attitude.</p> |
