Pressure relief valve for pressure equalization between a closed space and the surrounding atmosphere

摘要

A pressure relief valve includes a valve housing and a drop-shaped body with a conical valve surface that cooperates with a conical valve seat at an upwardly directed blow-off opening of the valve housing. The drop-shaped body is connected to a lifting disc in the housing. The inner configuration of the housing provides an annular passage around the lifting disc which is smaller in area when the lifting disc (and drop-shaped body) is in its uppermost, fully open positioning as compared to its lowermost, closed positioning.