Non-leakage type slide valve

Claim 1

IN A CYCLIC SLIDING SPOOL VALVE DEVICE, A HOUSING HAVING AN ANNULAR SEALING CARTRIDGE THEREIN DEFINING AN APERTURE AND HAVING SPACED CHAMBERS ON OPPOSITE SIDES OF SAID APERTURE AND CONNECTED THERETO, A SPOOL MOVABLY POSITIONED IN SAID APERTURE FOR BLOCKING THE FLOW OF FLUID THERETHROUGH FROM ONE OF SAID CHAMBERS TO THE OTHER THEREOF, SAID SEALING CARTRIDGE HAVING A SEMI-RESILIENT SLEEVE MEMBER IN THE WALL OF SAID APERTURE AND ENCOMPASSING SAID SPOOL WHEN SAID SPOOL IS IN SAID APERTURE AND AN O-RING MEMBER COMPRISING INWARDLY ONE END OF SAID SLEEVE MEMBER FOR PREVENTING LEAKAGE OF A FLUID BETWEEN SAID SLEEVE MEMBER AND SPOOL, AND PERMEABLE FOLLOW-UP MEANS INTERCHANGEABLY POSITIONABLE WITH SAID SPOOL AND MOVABLE THEREWITH DURING AT LEAST A PORTION OF THE MOVEMENT OF SAID SPOOL, SAID PERMEABLE FOLLOW-UP MEANS PASSING SAID FLUID THERETHROUGH FROM SAID ONE OF SAID CHAMBERS TO THE OTHER THEREOF WHEN SAID SPOOL IS WITHDRAWN FROM SAID APERTURE.