RECIRCULATION VALVE Russian patent published in 1995 - IPC

FIELD: valving. SUBSTANCE: vortex chamber of a housing has inlet passage and outlet nozzle. A valving member is mounted inside the inlet space of the housing. A pilot valve is coupled with a control drive. A converging pipe is mounted upstream of the inlet passage. The valving member is constructed as a spring- loaded piston with the hollow rod mounted for interaction with a seat positioned inside the converging pipe. A passage, which connects the space of the piston with the inlet space of the housing, is made in the housing. A throttle opening is made in the cylindrical wall of the hollow rod. The opening connects the under-piston space of the piston with the space of the rod. The pilot valve is mounted for permitting overlapping the passage of the housing. Openings are made in the face surface of the piston. These openings connect the space of the piston with the space of the spring. EFFECT: improved design. 5 cl, 3 dwg