Patent ID: 6840498
Filing Date: 2005-01-11
Classification: F16K

Abstract:
1. A zero pressure electromagnetic server, comprising: a main body having a first valve opening and a second valve opening located in a valve passage which communicates with an inlet and an outlet; and a valve stem having a first sealing side to seal the first valve opening and a second sealing side to seal the second valve opening, and a center opening formed in the interior thereof leading to an axial flow opening normal to the center opening to communicate with a space formed by the two valve openings; wherein a positive pressure enters into the main body to generate a thrust force on the first sealing side, the positive pressure being channeled through the axial flow opening to synchronously generate a bucking force on the second sealing side opposite to the thrust force, the first sealing side and the second sealing side having a same pressure receiving area such that the thrust force and the bucking force are offset with each other to create a zero pressure and no loading state for the valve stem.