Multi-stage valve with an axially removable seat to push a valve element in tightly coupled coupling to another seat

摘要

A multi-stage valve comprising: - a housing (2) having an axial bore (3) that connects with at least first, second and third holes (A, B, C) for fluids; - a valve element (5) that is axially removable in the bore (3) between first and second extreme positions; - a first seat (24) for the valve element (5) to be tightly coupled therewith in the first extreme position while the first and second orifices (A, B) for fluid are disconnected from each other; - a second seat (10) for the valve element to engage in a stay with it in the second extreme position while the second and third holes (B, C) for fluid are disconnected from each other; and - first operable operating means for moving the valve element (5) in the axial direction towards its first extreme position, in which the second seat (10) is axially removable in the perforation (3), characterized in that, the second The seat is axially slidable inside the perforation (3) between a starting position and an advanced switching position, in which the first operating means are designed to act on the second seat (10) to slide it in the axial direction from its starting position to its forward switching position when operated while the second seat (10) pushes the valve element (5) towards its first extreme position while the valve element (5) remains tightly coupled with the second seat (10) during this movement, and in which the second seat (10) has the freedom to return automatically from its forward switching position n to its starting position when no first means of operation in which the second seat (10) operate, and is pushed out to its starting position.