Pressure actuated switching valve

An aircraft comprising:

• a fuselage;
• at least one engine supported by the fuselage;
• a mechanical system arranged in the fuselage, the mechanical system including a pressure actuated switching valve comprising:
• a valve chamber, wherein the valve chamber includes
• a first chamber portion defining an inlet, the first chamber portion having a first inner diameter;
• a second chamber portion defining an outlet, the second chamber portion having a second inner diameter that is greater than the first inner diameter;
• a first sealing surface defined between the first chamber portion and the second chamber portion,
• a third chamber portion having a third inner diameter that is greater than the first inner diameter,
• a fourth chamber portion having a fourth inner diameter that is greater than first inner diameter, and
• a fifth chamber portion;
• a second sealing surface defined at an interface of the first chamber portion and the second chamber portion;
• and
• a valve member slidingly arranged in the valve chamber, wherein the valve member includes
• a first section arranged in the second chamber portion, the first section having a first outer diameter that is greater than the first inner diameter and being configured to selectively engage the sealing surface,
• a second section arranged in the third chamber portion, the second section having a second outer diameter that is closely matched to the third inner diameter, and
• a third section arranged in the fourth chamber portion having a third outer diameter that is greater than the first outer diameter, the second outer diameter, and the second inner diameter.

A method of operating a pressure actuated switching valve comprising:

• introducing a fluid into a valve chamber having a first chamber portion including a first inner diameter, a second chamber portion having a second inner diameter that is greater than the first inner diameter, a third chamber portion having a third inner diameter that is greater than the first inner diameter, a fourth chamber portion having a fourth inner diameter that is greater than first inner diameter, and a fifth chamber portion;
• snapping the pressure actuated switching valve open by unseating a first section of a valve member from a sealing surface defined between the first chamber and the second chamber portion with a first fluid pressure directed at the first section;
• holding the pressure actuated switching valve open with the first fluid pressure acting on the first section and a second fluid pressure acting on a third section of the valve member in the fifth chamber portion;
• passing a portion of the first fluid through an outlet connected to the second chamber portion;
• reducing the first fluid pressure;
• and
• snapping the valve member closed seating the first section on the sealing surface with a spring positioned in the fifth chamber portion.