Device for generating a negative pressure in the sealed room of a tablet press and/or of an isolator

A device for generating a negative pressure in the sealed room of a tablet press and/or of an isolator, with a fan connected to the sealed room and an air opening towards the sealed room, wherein the intake side of an ejector is connected with the sealed room, the working fluid connection of which is connectable with a compressed air source via a valve, with a sensor which is connected to a negative pressure control unit which opens the valve when the sensor measures a pressure in the sealed room which is above a predetermined negative pressure value, a second valve being assigned to the fresh air inlet opening, which depending on the embodiment remains opened or is triggered and closed by the negative pressure control unit.