Drill bit nozzle

Claim 1

A ROTARY DRILL BIT INCLUDING A BODY HAVING A CUTTER MEANS MOUNTED THEREON AND A PASSAGE FOR DISCHARGING DRILLING FLUID DOWNWARDLY FROM THE BODY; A REPLACEABLE, HARD, BRITTLE NOZZLE OF CIRCULAR CROSS-SECTION ADAPTED TO BE SLIPPED UPWARDLY INTO THE BODY PASSAGE FOR CONTROLLING THE DISCHARGE OF FLUID FROM THE BODY; A CIRCUMFERENTIAL GROOVE IN THE OUTER WALL OF THE NOZZLE; A CIRCUMFERENTIAL GROOVE IN THE INNER WALL OF THE BODY PASSAGE SURROUNDING THE NOZZLE AND SPACED VERTICALLY IN THE BODY PASSAGE TO MATCH THE CIRCUMFERENTIAL GROOVE IN THE NOZZLE SO THAT THE BODY AND NOZZLE GROOVES TOGETHER FORM A FIRST PASSAGEWAY WHOSE WALLS ARE LONGITUDINALLY DIVIDED BETWEEN THE NOZZLE AND BODY; A SECOND PASSAGEWAY EXTENDING FROM THE EXTERIOR OF THE BODY TO THE FIRST PASSAGEWAY; AN ELONGATE, STIFF, BENDABLE BUT NON-RESILIENT RETAINER MEMBER HAVING PORTIONS THEREOF DISPOSED IN THE FIRST AND SECOND PASSAGEWAYS WITH THE PORTION IN THE FIRST PASSAGEWAY BRIDGING BETWEEN THE GROOVES IN THE NOZZLE AND BODY AND PREVENTING ENDWISE DISPLACEMENT OF THE NOZZLE FROM THE BODY; THE NOZZLE AND BODY GROOVES AND THE RETAINER MEMBER PORTION THEREIN BEING VERTICALLY SPACED BELOW THE UPPER END OF THE NOZZLE AND SUFFICIENTLY FAR ABOVE THE LOWER END OF THE NOZZLE THAT THEY ARE ISOLATED FROM IMPINGEMENT BY TURBULENT DRILLING FLUID WITH ABRASIVE PARTICLES THEREIN WHICH IS DISCHARGED FROM THE NOZZLE; AND A RESILIENT FLUID ENERGIZED SEAL MEANS OF THE ORING TYPE BETWEEN THE NOZZLE AND BODY ABOVE THE NOZZLE AND BODY GROOVES PREVENTING DRILLING FLUID FROM FLOWING DOWNWARDLY BETWEEN THE NOZZLE AND BODY; SAID SECOND PASSAGEWAY HAVING A LATERAL DIMENSION SUFFICIENTLY LARGER THAN THE CORRESPONDING LATERAL DIMENSION OF THE RETAINER MEMBER PORTION IN THE SECOND PASSAGEWAY SUCH THAT THE RETAINER MEMBER CAN BE ROTATED ABOUT THE LONGITUDINAL AXIS OF THE NOZZLE TO ELIMINATE THE FULCRUMING ACTION EXERTED ON THE NOZZLE BY THE RETAINER MEMBER AS THE LATTER IS DRIVEN INTO PLACE, THEREBY PERMITTING THE NOZZLE TO BE RECENTERED IN THE BODY PASSAGE BY THE SEAL MEANS.