Patent ID: 8453647

Claim:
A pressure relief device for pressure equalization for an electromechanically driven medical gas delivery means in a medical device for respirating a patient with a gas volume flow which is adapted to an operating state of the medical device for respirating the patient and to an operating state of the electromechanically driven medical gas delivery means, the pressure relief device comprising: a first gas port; a second gas port; a relief valve with a valve disk and a valve seat; a bypass stream branch connecting the first gas port to the relief valve; a pressure relief outlet; an equalization space; and a nonreturn valve, the equalization space connecting the second gas port to the relief valve via the nonreturn valve, the valve disk being in pneumatic connection with the electromechanically driven medical gas delivery means via a front-side surface area and via a rear-side surface area, wherein: the front-side surface area is made larger than the rear-side surface area and a front-side force acts on the valve disk via the front-side surface area and a rear-side force acts on the valve disk via the rear-side surface area at an operating pressure and a pressure level in the equalization space; a distance between the valve disk and the valve seat is determined by an operating pressure and a prevailing pressure in the equalization space and by a ratio of the front-side surface area to the rear-side surface area and by a ratio of the front-side force to the rear-side force, so that a partial volume flow, of the gas volume flow, flows off into the environment via the bypass stream branch, via the relief valve and via the pressure relief outlet.