Patent ID: 6820645
Filing Date: 2004-11-23
Classification: F15B,Y10T

Abstract:
An unlockable non-return valve for very high system pressures having a valve housing (35) with a continuous receiving bore (36) located on a valve axis (37), having a closing element (50) which is prestressed in closing direction by a closing spring (51) and moveable in direction of the valve axis (37), having a poppet piston (70) which is actable upon at a piston collar (71) by a control pressure in order to unlock the closing element (50) and, on both sides of the piston collar (71), is guided on end sections (79, 80) of at least approximately identical diameters in the direction of the valve axis (37), and having two inserts (44, 60, 55, 60), which are placed into the receiving bore (36), on each side of the piston collar (71), into which the poppet piston (70) dips with an end section (79, 80), the end section (79, 80) being guided in an insert (60) which is close to the piston collar (71) and is made from a metallic material having good sliding properties, and a second insert (44, 55) following the first insert (60) has, in a turn-out (84) which is open radially toward the end section (79, 80) and axially toward the first insert (60), a high-pressure seal (86) which bears radially against the end section (79, 80) of the poppet piston (70) and is supported axially by the first inset (60), wherein the first insert (60) has a guide diameter for the end section (79, 80) of the poppet piston (70) over just a short section of its end side facing the piston collar (71), and by the fact that a supporting ring (88) is arranged axially between the high-pressure seal (86) and the first insert (60) in a receiving element (87) which is formed between the two inserts (44, 60, 55, 60) and is open radially toward the end section (79, 80) of the poppet piston (70) and diameter of which is substantially smaller than the outside diameter of the inserts (44, 60, 55, 60), said supporting ring (88) likewise being made of a metallic material having good sliding properties and being produced with a narrow clearance from the end section (79, 80) of the poppet piston (70) and with a large radial clearance from the receiving element (87).