摘要 |
<p>A compressed air breathing apparatus, in particular for underwater diving, comprising a compressed air supply (1) communicating with a chamber (15) for expanding the compressed air, through a valve (6,7,2,10,13,3,14) whose opening and closing are controlled by a diaphragm (4) responsive to the inhaling effort on the part of the user, and a mouthpiece (22) comprising a conduit (21) which puts the expansion chamber (15) in communication with the mouth of the user. According to the invention, the conduit (21) of the mouthpiece (22) includes a tongue (5) for forming an obstacle to the free flow of the air from the expansion chamber (15) to the mouth of the user, the tongue (5) being so arranged that the depression required for opening the valve is between -6 millibars and +6 millibars for a rate of flow of 400 liters/min. The tongue (5) is adjustable as to position to vary the extent to which it impedes free flow of the air.</p> |