| 摘要 |
<p>A dual air supply breathing apparatus that allows a user to quickly and easily switch between two or more sources of air or compressed gas, such as filtered air from a Powered Air Purifying Respirator (PAPR) and compressed air from a Self-Contained Breathing Apparatus (SCBA). In one variation, the dual air supply breathing apparatus uses a Y-shaped changeover valve with two input tubes and one output tube. The first input tube receives filtered air from a PAPR and the second input tube receives compressed air from a tank. An actuator controls a flap valve within the changeover valve to seal off one of the input tubes while creating a flow path between the other input tube and the output tube. The changeover valve may be controlled by manipulating the high-pressure valve on the tank of compressed gas and/or by manipulating the switch that activates the PAPR.</p> |
