OVERLOAD PROTECTION OF PNEUMATIC PRESSURE SENSORS WITH A SINGLE DIAPHRAGM

摘要

pneumatic pressure detector of the type where the pressure to be detected acting on a diaphragm (50) moves to regulate the evacuation of gas from a pressurized control chamber (20). Means are provided for inhibiting or preventing the membrane overload. To support the membrane against excessive external pressure, it is fixed with a small spacing in front of a bearing plate (10); while to protect against excessive internal pressure, first, the mechanical stop members (62) are provided to limit the displacement outwardly of a rod (60) fixed to the center of the membrane, and secondly, means pressure control are provided for limiting to a predetermined degree, and compared with the pressure acting externally, the maximum gas pressure which can be exerted on the inner face of the membrane.