| 摘要 |
<p>A vent valve for a buoyancy control device suitable for free-swimming divers, where the valve is opened both manually and by a powered means, such as from a hydraulic or pneumatic pressure line 25, the hydraulic or pneumatic pressure is equalised with the ambient pressure when not activated. The manual opening means comprises a manual pull dump 33 and 35 that is arranged such that it is not resisted by a piston 27 of the powered means. Water ingress into a bladder 1 of the buoyancy control device is restricted by a one-way valve 31 within the vent valve. The vent valve forms part of a venting system (Fig 2) for the buoyancy control device that comprises at least three vent valves which are opened simultaneously on operation of the powered opening means.</p> |
