Valve device

A two-way check valve, comprising:

• a valve housing with first and second control guides and with first and second valve seats therein, said valve seats having first and second sealing edges, respectively;
• first, second and third fluid connections in said valve housing;
• a control rod being axially movable in said first and second control guides and said valve housing and having oppositely directed first and second piston surfaces at opposite ends of said control rod;
• first and second conical valve pistons having first and second conical surfaces, respectively, and being movably mounted on said control rod and movable in said valve housing relative to said first and second sealing edges, respectively, between closed positions engaging said first and second sealing edges, respectively, and closing fluid communication between said first and second fluid connections, respectively, with said third fluid communication and open positions spaced from said first and second sealing edges, respectively, and opening fluid communication between said first and second fluid connections, respectively, with said third fluid connection;
• first and second springs biasing said first and second valve pistons to the closed positions thereof;
• first and second radial surfaces on said control rod between said valve pistons engageable with said valve pistons to move said valve pistons independently and separately to the open positions thereof upon axial movement of said control rod in respective axial directions;
• and
• valve ducts in said valve elements and control ducts in said control rod providing fluid communication between said first and second fluid connections and longitudinal ends of said control rod.

A two-way check valve, comprising:

• a valve housing having axially extending and inwardly facing first and second housing guide surfaces therein;
• first, second and third fluid connections in said valve housing;
• first and second valve elements axially displaceably mounted in said valve housing, said first and second valve elements including first and second conical pistons having first and second conical surfaces, respectively, and including axially extending and outwardly facing element guide surfaces thereon respectively engaging said first and second housing guide surfaces;
• a control device controlling displacement of said valve elements in said valve housing;
• first and second seats in said valve housing forming leak-tight closures for the respective fluid connections with said first and second valve elements, respectively, said first and second seats including first and second sealing edges, respectively, in said valve housing and engaged by said first and second conical surfaces, respectively, to form said leak-tight closures, said first and second conical pistons being biased by first and second energy storages, respectively, toward closed positions thereof in which said first conical piston seals said first fluid connection and said second conical piston seals said second fluid connection in leak-free manners relative to said third fluid connection, said third fluid connection adjoining said first and second sealing edges;
• and
• valve ducts in said valve elements and control ducts in said control device providing fluid communication between said first and second fluid connections and longitudinal ends of said control device.