| 主权项 |
1. Double counterlung breathing apparatus for a diver submerged beneath the surface of a body of water while being supplied with breathing gas from a breathing circuit, the double counterlung breathing apparatus comprising:
a double counterlung forming a first part of the breathing circuit and configured to be carried by the submerged diver, the double counterlung having a supply chamber and a return chamber that are connected for inflation and deflation in unison; equipment that forms a second part of the breathing circuit and reprocesses the breathing gas expelled by the diver and pumps the reprocessed gas back to the diver, the equipment being disposed apart from and remote from the double counterlung; the equipment including a gas compressor that is configured for pumping breathing gas to the double counterlung; the equipment including a gas reprocessing unit that is configured for removing carbon dioxide expelled by the diver to the double counterlung and for maintaining the required partial pressure of oxygen in the breathing gas to be supplied to the double counterlung; a supply duct that forms a third part of the breathing circuit extending between the equipment and the double counterlung and that carries to the double counterlung, breathing gas pumped from the equipment for the diver's breathing; wherein the double counterlung further being configured to shut off the supply duct when the double counterlung reaches its maximum volume causing a rapid increase in the pressure of the gas in the supply duct; a return duct that forms a fourth part of the breathing circuit extending between the equipment and the double counterlung and that carries back to the equipment for reprocessing, breathing gas expelled by the diver to the double counterlung during the diver's respiration; wherein the double counterlung further being configured to shut off the return duct when the double counterlung reaches its minimum volume causing a rapid drop in the pressure of the gas in the return duct; the equipment including a first detector that upon detecting the minimum volume of said double counterlung signals the equipment to add breathing gas to said return duct, said first detector being positioned upstream of said compressor, said first detector including an inlet regulator responsive to the rapid drop of pressure in said return duct caused by the return duct being shut off at the double counterlung, to add breathing gas to said return duct, but said first detector not being responsive to slow reductions in pressure caused by the double counterlung moving toward reduced depths beneath the surface of the body of water; and the equipment including a second detector that upon detecting the maximum volume of said double counterlung signals the equipment to vent breathing gas from said supply duct, said second detector being positioned downstream of said compressor in use, said second detector including an outlet regulator responsive to the rapid increase of pressure in said supply duct caused by the supply duct being shut off at the double counterlung, to vent breathing gas from said supply duct, but not responsive to the slow increase in pressure caused by the double counterlung moving toward increased depths beneath the surface of the body of water. |
