Low pressure packer mandrel

Claim 1

IN A DEVICE OF THE CHARACTER DESCRIBED, A VERTICALLY DISPOSED WELL CASING, A TUBING ARRANGED IN SAID CASING AND INCLUDING A PLURALITY OF CYLINDRICAL SECTIONS COUPLED TOGETHER, A PAIR OF RESILIENT CUPS MOUNTED ON ONE OF THE SECTIONS OF TUBING, SAID CUPS BEING ADAPTED FOR SEALING CONTACT WITH THE INNER SURFACE OF SAID CASING, AND SAID CUPS HAVING CLOSED ENDS WHICH ARE ADJACENT EACH OTHER, A SUPPORT MEMBER POSITIONED IN SAID ONE SECTION OF TUBING AND HAVING A HOLLOW INTERIOR WHICH DEFINES A CHAMBER, THERE BEING A PASSAGEWAY IN THE LOWER END OF SAID SUPPORT MEMBER, A VALVE SEAT CONTIGUOUS TO SAID PASSAGEWAY, A BALL MOUNTED FOR MOVEMENT INTO AND OUT OF OPEN AND CLOSED RELATION WITH RESPECT TO SAID VALVE SEAT, A STOP PIN ABOVE SAID BALL, A SECTION OF TUBING ABOVE SAID FIRST NAMED SECTION WHICH IS PROVIDED WITH UPPER AND LOWER OPENINGS THEREIN, UPPER AND LOWER ANNULAR SHIELDS SURROUNDING SAID LAST NAMED SECTION ADJACENT SAID OPENINGS, THERE BEING PASSAGEWAYS IN SAID SHIELDS CONNECTED IN COMMUNICATION WITH SAID UPPER AND LOWER OPENINGS AND WITH THE ANNULAR SPACE BETWEEN SAID CASING AND SAID TUBING ABOVE SAID CUPS, AND HOLLOW TUBES CONNECTING THE PASSAGEWAYS IN SAID UPPER AND LOWER SHIELDS TOGETHER.