| 摘要 |
<p>A device which will act efficiently as a float for any article (e.g. keys, mobile telephone, wallet) attached thereto when dropped into water comprises an inflatable bag (14) of substantially waterproof and air impervious material, a container (12) of compressed gas, and trigger means (16,30,32) associated with the container (12) and operable upon immersion of the device in water to open the container (12) and allow gas from the container (14) to inflate the bag (14). The trigger means comprises a valve (16) mounted on the container (12) and connecting the container to the inflatable bag (14), retainer means (30) operative to hold the valve (16) in a closed condition, and water reactive means (32) which, upon contact with water, serves to release the retainer means (30) and allow the valve to open. The water reactive means may comprise a band of material (32), at least part of which is water reactive. The retainer means may comprise a spring (30) which acts directly on the valve (16) to keep it closed against spring bias and the water reactive band (32) may hold the spring (30) under compression until release. In other embodiments the retainer means may comprise a plate or a lever which the water reactive band holds against spring bias of the valve to its open position until release. In another embodiment the retainer means includes a spring held under compression by a water reactive band, which spring, upon release overcomes spring bias of the valve to its closed position. The bag (14), the container (12) and the trigger means are housed a casing (10) and means (37) are provided, preferably integrally on the container (12), for attachment of the device to another article.</p> |
