Check valve with removable filter

Claim 1

AN ADJUSTABLE CHECK VALVE COMPRISING: A VALVE CASING HAVING INLET AND OUTLET OPENINGS TO ACCOMMODATE THE FLOW OF FLUID INTO AND OUT OF SAID CASING, RESPECTIVELY, A PARTITION DISPOSED BETWEEN SAID INLET AND OUTLET OPENINGS TO FORM INLET AND OUTLET COMPARTMENTS, SAID PARTITION HAVING A VALVE PORT AND A VALVE SEAT, AN ACCESS OPENING FOR SAID OUTLET COMPARTMENT AND SAID OUTLET OPENING IN THE WALL OF SAID CASING, A TRANSVERSELY PROJECTING SUPPORT COMPRISING A WEB EXTENDING PARTIALLY ACROSS SAID COMPARTMENT IN A PLANE SUBSTANTIALLY PARALLEL WITH SAID VALVE PORT SO AS TO DEFINE A SPACE BETWEEN SAID WEB AND THE WALL OF SAID CASING, SAID WEB HAVING AN APERTURE THEREIN SUBSTANTIALLY ALIGNED WITH SAID VALVE PORT, A SHAFT MOUNTED ON SAID SUPPORT FOR AXIAL MOVEMENT A VALVE RESILIENTLY COUPLED TO SAID SHAFT AND ADAPTED FOR SEALING ENGAGEMENT WITH SAID VALVE SEAT, SAID VALVE EXERTING AGAINST SAID VALVE SEAT A THRUST HAVING A MAGNITUDE PREDETERMINED BY THE AXIAL POSITION OF SAID SHAFT RELATIVE TO SAID SUPPORT, A FILTER IN SAID OUTLET COMPARTMENT EFFECTIVELY DISPOSED ACROSS SAID OUTLET PORT, SAID FILTER BEING MOVABLE THROUGH SAID SPACE FOR PURPOSES OF INSERTING AND WITHDRAWING SAID FILTER IN AND FROM SAID COMPARTMENT AND A REMOVABLE COVER FOR SAID ACCESS PORT, SAID COVER HAVING A CENTRALLY DISPOSED CYLINDRICAL HOLE ENGAGING SAID SHAFT IN ROTATABLE, AXIALLY MOVABLE AND FLUID TIGHT RELATION.