Check Valve/Vacuum Generator/Flow Switch AP     SUMMARY Fluid back-flow is prevented by back pressure. Unique design with only one moving part in the gas stream, an O-ring. Springless structure suppresses particle generation by vibration or chattering or pressure fluctuation on downstream side. [Vacuum generator] Vacuum generation equipment. Applicable to emission of unnecessary gas remaining inside the piping during gas cylinder replacement. [Flow switch] Detects excess flow above a given flow rate, caused by pipe breakage, etc.