Patent ID: 7950621

Claim:
A pneumatic crankcase pressure regulating valve for regulating gas pressure in a crankcase of an internal combustion engine, the pressure regulating valve being arranged in the path of a crankcase ventilation line and having an opening which can be automatically changed by means of the pressure regulating valve in relation to a differential pressure between a reference pressure and one or more gas pressures applied to at least one inlet of the pressure regulating valve, comprising a control diaphragm including a closing element located in the pressure regulating valve, the control diaphragm being subjected to the reference pressure on one side thereof and being subjected to the gas pressure as well as to a governor spring on an opposite side, wherein a change in the differential pressure between regions adjacent to the control diaphragm causes an adjustment of the control diaphragm in the form of a movement of the control diagram, and the movement of the control diaphragm increases or reduces an outflow cross-section of the valve opening, a structure of the pressure regulating valve arranged adjacent to the outflow cross-section on the diaphragm side to form a valve seat stop for the closing element of the control diaphragm in a closed position of the control diaphragm, at least one rigid, non-elastic and non-flexible preliminary stop arranged in the pressure regulating valve such that, when the control diaphragm is moving in its closing direction, the control diaphragm first comes into contact with the preliminary stop, the preliminary stop comprising a single pin in the interior of the valve seat stop, the control diaphragm having at least a portion that is formed of an elastomeric material that is elastic and flexible, such that when the control diaphragm is moving further in its closing direction, the control diaphragm will then, while being subjected to elastic and flexible deformation, further reduce the cross-section of the valve opening and, in a final position, also come into contact with the valve seat stop.