Patent ID: 7845368
Filing Date: 2010-12-07
Classification: F16K,Y10T

Abstract:
1. Double seat valve comprising two valve housing parts ( 1 a , 1 b ) and first and second closing elements ( 3 , 4 ) arranged in series and movable with regard to each other, which prevent in a closed position of the double seat valve ( 1 ) fluids from one of the valve housing parts (l a ; l b ) flowing into the other of the valve housing parts ( 1 a , 1 b ), which define in the closed position, as well as in the open position, a leakage cavity ( 5 ) between them, which is connected with the surroundings of the double seat valve ( 1 ), wherein in the closed position the first closing element ( 3 ), which is formed as a slide piston, is received in sealing manner in a connecting opening ( 2 c ) connecting the valve housing parts ( 1 a , 1 b ) with each other and which comes to abut, in a sealing manner in the course of its opening movement, the second closing element ( 4 ), which is associated with a second seat ( 2 b ), and the latter element is also transferred to an open position (H) during a further opening movement, the first closing element ( 3 ) comprising a first seal ( 6 ) at its end section ( 3 *), which seals radially against a cylindrical first seat ( 2 a ) formed in the connecting opening ( 2 c ), the second closing element ( 4 ) comprising at its end facing towards the first closing element ( 3 ) a recess ( 4 b ) with a substantially cylindrical peripheral wall ( 4 c ) aligned with the cylindrical first seat ( 2 a ), and the recess being dimensioned in order to sealingly receive the end section ( 3 *) and the radial first seal ( 6 ) of the first closing element ( 3 ) during the opening movement, before the second closing element ( 4 ) opens, each of the closing elements ( 3 , 4 ) being able to be transferred independently from the other by a partial lift to a seat cleaning position in order to rinse its respective coaxial seat ( 2 a , 2 b ), wherein the second closing element ( 4 ) can be transferred to its seat cleaning position by a second partial lift (T 2 ) in the same direction as the opening movement and the first closing element ( 3 ) can be transferred to its seat cleaning position by a first partial lift (T 1 ) in the direction opposed to the opening movement, a cylindrical lug ( 3 *, 4 *) being arranged at each closing element ( 3 , 4 ) on the leakage cavity side, which forms an annular choke gap (D 1 , D 2 ) with the associated connecting opening ( 2 c ), the first seat ( 2 a ) having a diameter that is smaller than the diameter of an annular recess ( 2 d ) associated with the second closing element ( 4 ) in the connecting opening ( 2 c ) , and a transition surface ( 2 e ) between the first seat ( 2 a ) and the annular recess ( 2 d ), characterised in that the second closing element ( the circumferential wall ( and that, viewed in vertical center section, the diversion area (