Flow control valve for usb in a well tubing string

Claim 1

A WELL FLOW CONTROL DEVICE FOR USE IN A WELL TUBING STRING INCLUDING: AN ELONGATE HOUSING HAVING A BORE EXTENDING THERETHROUGH; MEANS FOR CONNECTING SAID HOUSING IN A WELL TUBING STRING WITH THE BORE OF SAID HOUSING IN ALIGNMENT WITH THE BORE OF SAID TUBING STRING; A VALVE ELEMENT HAVING A PASSAGE EXTENDING LONGITUDINALLY THERETHROUGH AND MOUNTED FOR MOVEMENT LONGITUDINALLY WITHIN SAID HOUSING BETWEEN A FIRST POSITION AND A SECOND POSITION; SEAL MEANS BETWEEN SAID VALVE ELEMENT AND SAID TUBULAR HOUSING FOR SEALING BETWEEN SAID VALVE ELEMENT AND SAID HOUSING WHEREBY FLUID FLOWING THROUGH SAID HOUSING MAY PASS ONLY THROUGH SAID VALVE ELEMENT PASSAGE; VALVE MEANS MOUNTED WITHIN SAID HOUSING AND OPERATIVELY ASSOCIATED WITH SAID VALVE ELEMENT FOR OPENING AND CLOSING SAID PASSAGE IN ACCORDANCE WITH THE MOVEMENT OF SAID VALVE ELEMENT, SAID VALVE MEANS OPENING SAID PASSAGE WHEN SAID VALVE ELEMENT IS IN SAID FRIST POSITION, SAID VALVE MEANS CLOSING SAID PASSAGE WHEN SAID VALVE ELEMENT IS IN SAID SECOND POSITION; RESILIENT MEANS IN SAID HOUSING DISPOSED ABOUT SAID VALVE ELEMENT AND ENGAGING SAID HOUSING AND SAID VALVE ELEMENT AND BIASING SAID VALVE ELEMENT TO SAID FIRST POSITION WHEREIN SAID PASSAGE IS OPEN; A COLLET DISPOSED ABOUT SAID VALVE ELEMENT AND MOUNTED IN FIXED POSITION RELATIVE TO SAID HOUSING; RECESS MEANS ON THE EXTERIOR OF SAID VALVE ELEMENT, SAID COLLET HAVING YIELDABLE LATCH MEANS ENGAGEABLE WITH SAID RECESS MEANS ON THE EXTERIOR SURFACE OF SAID VALVE ELEMENT WITH A FORCE SUPPLEMENTING THE FORCE EXERTED ON SAID VALVE ELEMENT BY SAID BIASING MEANS FOR RELEASABLY HOLDING SAID VALVE ELEMENT IN SAID FIRST POSITION WHEREIN SAID PASSAGE IS OPEN; AND MEANS RESTRICTING SAID PASSAGE OF SAID VALVE ELEMENT WHEREBY A PREDETERMINED RATE OF FLUID FLOW THROUGH SAID PASSAGE PRODUCES A DIFFERENTIAL PRESSURE ACTING ON SAID VALVE ELEMENT WITH A FORCE IN EXCESS OF THE FORCE WITH WHICH SAID BIASING MEANS AND SAID YIELDABLE LATCH MEANS OF SAID COLLET SLEEVE RESTRAINS SAID VALVE ELEMENT IN SAID FIRST POSITION TO RELEASE SAID LATCH MEANS AND MOVE SAID VALVE ELEMENT FROM SAID FIRST POSITION TO SAID SECOND POSITION WITH A SUDDEN SNAP ACTION, THEREBY OPERATING SAID VALVE MEANS FOR CLOSING SAID PASSAGE.