Moving sprinkler head

Claim 1

IN A SPRINKLER HEAD, A WATER TURBINE WHEEL FREELY ROTATABLE CONCENTRICALLY ABOUT A ROTATABLE NOZZLE MEMBER, SAID WHEEL HAVING A STRIKER WEIGHT PENDENT FROM A RADIALLY-EXTENSIVE AXIS SUPPORT THEREON BY MEANS OF A CIRCUMAMBIENTLY LOOSE FIT OF THE STRIKER WEIGHT SO AS TO BE VERTICALLY-SHIFTABLE ON SAID AXIS WHEREBY THE WEIGHT IS ROTATABLE ECCENTRICALLY ABOUT SAID AXIS, SAID NOZZLE MEMBER HAVING AN IMPACT MEMBER DISPOSED RADIALLY OF THE WHEEL AXIS AT A LEVEL IN THE PATH OF TRAVEL OF A LOWER PENDENT PORTION OF SAID STRIKER BELOW SAID SUPPORT AXIS TO BE HIT A DRIVING BLOW BY SAID LATTER PORTION ON ROTATION OF THE TURBINE WHEEL FOR THE PURPOSE OF TURNING SAID NOZZLE MEMBER A FEW DEGREES ON EACH SUCH IMPACT, THE ECCENTRICITY OF THE STRIKER ON ITS AXIS SUPPORT BEING SUFFICIENT TO PERMIT THE STRIKER TO RISINGLY ROLL OVER SAID IMPACT MEMBER ABOUT SAID RADIALLY-EXTENSIVE AXIS FOLLOWING THE INITIAL DRIVING IMPACT IN EACH INSTANCE WHEREBY TO ALLEVIATE STALLING OF THE TURBINE WHEEL.