Abstract: An inflatable aircraft evacuation slide system includes a primary valve, a bust disk and a valve leakage trap operatively disposed between the primary valve and the burst disk. The valve leakage trap comprises a small exhaust vent opening into a flow restriction orifice in the gas path between the primary valve and the burst disk. In operation, when the aircraft emergency exit is opened in the armed condition, the primary valve opens and pressurizes the chamber until the burst disk ruptures allowing inflation gases to pass through the flow restriction orifice to inflate the inflatable evacuation slide. Because there is a substantial pressure drop across the flow restriction orifice, the presence of the valve leakage safety vent in the orifice does not result in significant loss of inflation gas needed for inflating the inflatable evacuation slide. In the event of leakage past the primary valve, however, the valve leakage trap safely vents the leakage pressure to the atmosphere.

Abstract: An inflation valve for use with an inflatable emergency evacuation slide includes a thermally actuated gas relief valve having an exhaust port the effective size of which increases with increasing temperature. The exhaust port is metered by a valve member. The valve member position is controlled by a thermal actuator that lengthens with increasing temperature. At high ambient temperatures, the valve member moves to uncover the exhaust port thereby increasing the effective size of the port so that a large percentage of the inflation gas is vented. At low ambient temperatures the valve member moves to cover the exhaust port, thereby decreasing effective size of the exhaust port so that little or no inflation gas is vented.

Abstract: An emergency evacuation slide system includes a control valve having a normally-open vent that closes after a predetermined period of time calculated to vent excess inflation gas produced by the gas generator. In operation, in the event of an aircraft emergency exit door being opened in the “armed” condition, the primary valve member of the control valve is opened allowing inflation gas to flow into the valve chamber. A portion of the gas entering the chamber is vented through the normally-open vent. After a predetermined period of time calculated to be sufficient to vent the excess inflation gas, the normally-open valve is closed to divert 100% of the remaining inflation gas into the evacuation slide.

Abstract: An inflatable aircraft evacuation slide system includes a primary valve, a bust disk and a valve leakage trap operatively disposed between the primary valve and the burst disk. The valve leakage trap comprises a small exhaust vent opening into a flow restriction orifice in the gas path between the primary valve and the burst disk. In operation, when the aircraft emergency exit is opened in the armed condition, the primary valve opens and pressurizes the chamber until the burst disk ruptures allowing inflation gases to pass through the flow restriction orifice to inflate the inflatable evacuation slide. Because there is a substantial pressure drop across the flow restriction orifice, the presence of the valve leakage safety vent in the orifice does not result in significant loss of inflation gas needed for inflating the inflatable evacuation slide. In the event of leakage past the primary valve, however, the valve leakage trap safely vents the leakage pressure to the atmosphere.