Pressure regulating device

A first stage regulator for two-stage delivering assemblies, comprising:

• a first chamber for a breathable high pressure gas, the first chamber being adapted to be connected through an inlet to a high pressure breathable gas source;
• a second chamber for the breathable gas at an intermediate pressure, the second chamber having an outlet for the breathable gas and being adapted to be connected to a user of said breathable gas;
• and
• a pressure reducing valve which connects said first chamber and said second chamber with each other, the pressure reducing valve comprising a valve seat having a passage opening for communication between said first and said second chambers and a cut-off cooperating with said valve seat and displaceable from a closed position of said passage opening to an open position of said passage opening and vice versa,
• said cut-off being dynamically connected to a sensor exposed to the a pressure of an external environment of said first and said second chambers, the sensor comprising a transmitting mechanism adapted to transmit a mechanical stress exerted on said sensor by the pressure of the external environment of the cut-off,
• wherein said sensor comprises a rigid element of a movable wall which is sealingly slidable in a housing chamber, and which provides an interface wall of said housing chamber towards the external environment, and
• wherein said transmitting mechanism connects said movable wall with said cut-off.