Safety valve arrangement

A safety valve arrangement for an installation operating with a pressure medium, comprising:

• a pressure medium input and a pressure medium output;
• a valve located between said pressure medium input and said pressure medium output, said valve comprising a valve seat and a valve closing element, said valve closing element being moveable between an open position and a closing position, said valve closing element having an active surface subject to said pressure medium in the opening direction of said valve, said active surface constituting an area of said valve closing element which is delimited by said valve seat;
• said valve closing element further having an auxiliary surface located on an area of said valve closing element outside the area of said valve closing element which is delimited by said valve seat, said auxiliary surface being subject to said pressure medium in the opening direction of said valve only when said valve closing element is lifted from said valve seat;
• a spring arrangement holding said valve closing element in a first end position wherein said valve is closed, said valve closing element moving from said first end position to a second end position wherein said valve is open when the force of said pressure medium acting upon said valve closing element is greater than the opposing force of said spring arrangement acting upon said valve closing element;
• a choke located between said valve and said pressure medium output of said safety valve arrangement which throttles the flow of said pressure medium from said pressure medium input to said pressure medium output when said valve is in the open position,
• wherein said spring arrangement has a force as a function of a distance characteristic curve, a portion of which has a negative slope, and wherein the actuating pressure of said valve occurs along the negatively sloped portion of said curve.

The safety valve arrangement of 14 wherein said valve closing element of said valve is connected to a choke body having a diameter greater than the diameter of said valve closing element, said choke body is located on said valve closing element of said valve on a side of said valve closing element away from said valve seat;

• said diameter of said choke body and said diameter of said first zone of said bore are demensioned so that between an outer sleeve surface of said choke body and a wall delimiting said first zone of said bore, an annular gap remains which constitutes the choke;
• said choke body has a surface which serves as an active surface of said valve closing element and which is placed on said choke body so that the pressure medium coming from said pressure medium input of said safety valve arrangement acts upon it in the opening direction of said valve when said valve is open;
• and
• an axial extension of a first zone of a bore is demensioned so that said valve closing element of said valve is completely immersed in said bore, and an axial extension of said choke body is at least partially immersed In said first zone of said bore.

A safety valve arrangement for an installation operating with a pressure medium, comprising:

• a pressure medium input and a pressure medium output;
• a valve located between said pressure medium input and said pressure medium output, said valve comprising a valve seat and a valve closing element, said valve closing element being moveable between an open position and a closing position, said valve closing element having an active surface subject to said pressure medium in the opening direction of said valve, said active surface constituting an area of said valve closing element which is delimited by said valve seat;
• said valve closing element further having an auxiliary surface located on an area of said valve closing element outside the area of said valve closing element which is delimited by said valve seat, said auxiliary surface being subject to said pressure medium in the opening direction of said valve only when said valve closing element is lifted from said valve seat;
• a spring arrangement holding said valve closing element in a first end position wherein said valve is closed, said valve closing element moving from said first end position to a second end position wherein said valve is open when the force of said pressure medium acting upon said valve closing element is greater than the opposing force of said spring arrangement acting upon said valve closing element;
• a choke located between said valve and said pressure medium output of said safety valve arrangement which throttles the flow of said pressure medium from said pressure medium input to said pressure medium output when said valve is in the open position,
• wherein said spring arrangement further comprises an additional spring which pushes said valve closing element of said valve in the closing direction of said valve.