Fluid sealing device and analogue computer components

Claim 1

IN A PNEUMATIC OR HYDRAULIC DEVICE COMPRISING A CYLINDER HOUSING, A PISTON, A PISTON ROD AND A SELAING DEVICE FOR SEALING THE PERIPHERY OF SAID PISTON RELATIVE TO SAID CYLINDER HOUSING, SAID SEALING DEVICE COMPRISING A PLURALITY OF PLATES ENCOMPASSING SAID PISTON, SAID PLATES HAVING CONTIGUOUS SURFACES MUTUALLY SEALING EACH OTHER THEREBY, SAID PALTES HAVING ADDITION AND SUBSTANTIALLY PARALLEL TO SAID CONTIGUOUS SURFACES MUTUALLY SELAING EACH OTHER, SURFACE CONTIGUOUS WITH AND SEALING FROM ADJOINING SURFACES OF SAID CYLINDER HOUSING, SAID PLATES MOVABLY LOCATED IN A RECESS IN SAID CYLINDER HOUSING, SAID RECESS AND SAID PLATES BEING SUBSTNAITALLY NORMAL TO AXIS OF MOVEMENT OF SAID PISTON, SAID RECESS FORMING A SEAL WITH SIDES OF SAID PLATES, SAID PLATES HAVING INTERFACE EDGES CONFORMABLY SHAPED TO MATE SAID PISTON TO FORM A SUBSTANTIAL SEAL THEREBY AT SAID INTERFACE EDGES, SAID INTERFACE EDGES OF SAID PLATES OVERLAPPING EACH OTHER IN SUCH MANNAER THAT SAID PLATES MAY SLIDABLY MOVE TOWARD AND AWAY FROM THE CENTRAL AIXIS OF SAID PISTON ALONG THEIR SAID CONTIGUOUS SURFACES ON SUCH A MANNER THAT AID INTERFACE EDGE OF SAID PLATES MAINTAIN A REQUIRED DISTANCE FROM THE SIDE OF SAID PISTON EVEN THROUGH THE PERIPHERY OF SAID PISTON IS OF INCONSTANT DIMENSION AND A MEANS PROVIDED FOR CAUSING SAID PLATES TO MOVE TO MAINTAIN SAID REQUIRED DISTANCE.