Jetting device for rock bit

Claim 1

IN A ROCK DRILL BIT HAVING A DOWNWARDLY EXTENDING PASSAGE FOR DISCHARGING FLUSHING FLUID FROM THE BOTTOM OF THE BIT, A NOZZLE DISPOSED IN THE PASSAGE FOR EFFECTING DISCHARGE OF THE FLUID FROM THE BIT AT HIGH VELOCITY, THE NOZZLE BEING SLIDABLY REMOVABLE THROUGH THE DISCHARGE END OF THE PASSAGE, AN INTERNAL ABUTMENT IN THE PASSAGE ABUTTING THE UPPER END OF THE NOZZLE AND THEREBY DETERMINING THE UPWARD POSITION OF THE NOZZLE IN THE PASSAGE, A REDUCED EXTENSION OF THE NOZZLE DEPENDING FROM THE UNDERSIDE OF THE NOZZLE IN THE PASSAGE AND PROJECTING THROUGH THE DISCHARGE END OF THE PASSAGE, THE REDUCED EXTENSION HAVING A TRANSVERSE ANNULAR SHOULDER AT ITS UPPER END, AN ANNULAR GROOVE IN THE PASSAGE INTERMEDAITELY OF THE ENDS OF THE LATTER, A CONTRACTIBLE SPLIT SNAP RING HAVING AN OUTER PART SEATED IN THE GROOVE AND AN INNER PART ABUTTING THE UNDERSIDE OF THE SHOULDER WHEREBY THE NOZZLE IS BLOCKED FROM DROPPING OUT OF THE DISCHARGE END OF THE PASSAGE, THE SNAP RING HAVING AN INTERNAL DIAMETER GREATER THAN THE OUTER DIAMETER OF THE EXTENSION AND BEING CONTRACTIBLE OUT OF THE GROOVE TO THE DIAMETER OF THE PASSAGE UPON DRAWING THE FREE ENDS OF THE SNAP RING TOWARD EACH OTHER, THE SNAP RING HAVING A PAIR OF RADIALLY INTURNED EARS AT ITS FREE ENDS AND UPON BEING SO CONTRACTED THE SNAP RING BEING MOVABLE DOWNWARD OVER THE EXTENSION AND THROUGH THE DISCHARGE END OF THE PASSAGE ENABLING THEREBY REMOVAL OF THE NOZZLE FROM THE PASSAGE, AND THE EXTENSION PROJECTING OUT OF THE PASSAGE BEYOND THE BOTTOM END OF THE BIT WHEREBY THE DISTANCE BETWEEN THE SNAP RING AND THE DISCHARGE END OF THE NOZZLE IS EXTENDED ACCORDING TO THE EXTENT OF PROJECTION OF THE NOZZLE BEYOND THE BOTTOM END OF THE BIT.