| 摘要 |
<p>A deep diving breathing system in which a breathable gas mixture is circulated through a diving helmet by a push-pull pump includes an inlet flow control valve, an outlet gas flow regulator valve, and a bleed valve. The bleed valve operates in response to the pressure of gas flowing from the outlet gas flow regulator valve to bleed gas from a gas supply line upstream of the inlet flow control valve. The system facilitates diving operations from a diving bell at a range of depths and recovery of helium in a helium-oxygen breathing gas mixture.</p> |
