High pressure filter having a relief valve in the base

Claim 1

A HIGH PRESSURE FILTER COMPRISING A BASE HAVING SPACED INLET AND OUTLET CHAMBERS AND AN INTERMEDIATE DIVERSION CHAMBER, AN INLET PORT COMMUNICATING WITH THE INLET CHAMBER, AN OUTLET PORT COMMUNICATING WITH THE OUTLET CHAMBER, A PASSAGE EXTENDING THROUGH SAID INLET, OUTLET AND DIVERSION CHAMBERS, A FILTER CHAMBER ON SAID BASE, FILTER MEANS IN SAID FILTER CHAMBER, A FIRST FILTER PORT MEANS COMMUNICATING FROM ONE SIDE OF THE FILTER MEANS TO THE INLET CHAMBER, A SECOND FILTER PORT MEANS CONTINUOUSLY COMMUNICATING FROM THE OUTER SIDE OF THE FILTER MEANS TO THE DIVERSION CHAMBER, A SLIDING SPOOL IN THE PASSAGE MOVABLE LENGTHWISE THEREOF, MEANS ON THE SPOOL ACTING IN ONE POSITION OF THE SPOOL TO CLOSE ALL OF THE CHAMBERS IN THE BASE, IN A SECOND POSITION TO OPEN THE INLET CHAMBER TO THE FIRST FILTER PORT AND THE DIVERSION CHAMBER TO THE OUTLET CHAMBER AND IN A THIRD POSITION OPENING ALL CHAMBERS THROUGH THE PASSAGE TO PROVIDE COMMUNICATION DIRECTLY FROM THE INLET TO THE OUTLET PORTS BYPASSING THE FILTER CHAMBER AND RESILIENT MEANS CONTINUOUSLY URGING THE SPOOL MEANS TO THE FIRST POSITION, SAID RESILIENTLY MEANS BEING ADJUSTED TO PERMIT THE SPOOL TO MOVE SUCCESSIVELY FROM THE FIRST TO THE THIRD POSITION AT PRE-SELECTED FLUID INPUT PRESSURES.