| 主权项 |
1. In an oxygen supply system for delivering oxygen to passengers in an aircraft in the event of a loss of cabin pressure, the oxygen supply system including a source of oxygen, a reservoir bag for accumulating a volume of oxygen flowing from said source, and a face mask configured to force a passenger wearing said mask to inhale said accumulated volume of oxygen from said reservoir bag prior to allowing said passenger to inhale cabin air during each respiratory cycle, an improvement in the oxygen supply system comprising:
a pressure sensor fitted to said face mask, said pressure sensor being configured to detect a positive pressure within said face mask; an inlet valve configured to control a flow of oxygen to said reservoir bag; and a controller configured to open and close said inlet valve responsive to said pressure sensor to control the flow of oxygen to said reservoir bag to limit the flow of oxygen into said reservoir bag to a period of time during each respiratory cycle that is sufficient to allow only a selected volume of oxygen to accumulate in the reservoir bag, wherein said controller is configured to open said inlet valve immediately upon detection of said positive pressure within said face mask by said pressure sensor, and said controller is configured to control delivery of said selected volume of oxygen to said reservoir bag prior to inhalation of said selected volume of oxygen by the passenger. |
