SHUTTLE VALVE

A Pneumatic Shuttle Valve (often called an OR function valve) is a type of directional control valve used to supply a pneumatic signal or working pressure from one of two independent input lines to a single output line. ??? Function and Principle What it Does It implements the logical OR function in a pneumatic circuit. This means: If Input A has pressure OR Input B has pressure, the output will have pressure. If both inputs have pressure, the output will also have pressure. If neither input has pressure, the output will have no pressure. How it Works The valve typically contains a moving sealing element (like a ball, disk, or spool). When pressure is applied to one inlet port (say, A), the element is pushed towards and seals the other inlet port (B), allowing the air from A to flow freely to the outlet (O). If the pressure shifts to B, the element moves and seals A, allowing air from B to pass through to O. ?? Common Uses Shuttle valves are essential when an actuator needs to be started or a function needs to be triggered from two different locations or by two different control signals. Dual Control: Allowing a pneumatic cylinder to be extended from a push button at Station 1 or a push button at Station 2. Safety Overrides: Providing a means for a safety circuit to initiate a stop or trip function regardless of the normal operating signal. Sensing: In complex circuits, they can be used to combine the signals from multiple sensors or limit switches.