Pressure apparatus and means for charging the same with a pressure fluid

Claim 1

APPARATUS COMPRISING A CYLINDER DEFINING AN ENCLOSURE WITH AN OPENING TO AMBIENT ATMOSPHERE, A PISTON IN SAID CYLINDER DIVIDING SAID ENCLOSURE INTO TWO CHAMBERS ONE OF WHICH IS PROVIDED WITH SAID OPENING, THE OTHER OF SAID CHAMBERS CONTAINING A FLUID, A CYLINDRICAL CLOSURE IN FIXEDLY SECURED RELATION IN SAID OPENING AND SUBSTANTIALLY OBTURATING SAID OPENING BUT DEFINING WITH SAID CYLINDER A PASSAGE CONNECTING SAID ONE CHAMBER WITH AMBIENT ATMOSPHERE, SAID CLOSURE BEING PROVIDED WITH AN ANNULAR GROOVE COAXIAL WITH SAID CYLINDER, SAID GROOVE DEEPENING TOWARDS THE INTERIOR OF THE CYLINDER AND HAVING A SHAL OW PORTION AND A DEEP PORTION, AND AN ELASTIC PACKING RING ENCIRCLING SAID CLOSURE IN SAID GROOVE AND HAVING A DIAMETER WHICH IS NO GREATER THAN THATOF THE CLOSURE AT THE DEEP PORTION OF THE GROOVE, SAID GROOVE HAVING AN AXIAL EXTENT GREATER THAN THAT OF THE RING TO ACCOMMODATE AXIAL MOVEMENT OF THE RING, SAID RING BEING DISPLACEABLE FROM A FIRST POSITION AT THE SHALLOW PORTION OF THE GROOVE WHEREAT SAID RING IS SANDWICHED AGAINST SAID CYLINDER TO SEAL SAID PASSAGE, TO A SECOND POSITION AT THE DEEP PORTION OF THE GROOVE WHEREAT SAID RING IS SPACED FROM SAID CYLINDER AND SAID PASSAGE IS OPENED, SAID RING BEING DISPLACEABLE FROM SAID FIRST POSITION TO SAID SECOND POSITION BY THE DIRECTING OF A PRESSURE MEDIUM THROUGH SAID PASSAGE TOWARD SAID ENCLOSURE AND BEING DISPLACEABLE BY THE PRESSURE MEDIUM IN THE ENCLOSURE FROM THE SECOND POSITION TO THE FIRST POSITION TO SEAL THE PRESSURE MEDIUM IN THE ENCLOSURE.