Filter bed agitator and method

Claim 1

AGITATOR MECHANISM FOR WASHING AND CLEANING THE FILTER MEDIUM OF A FILTER BED, SAID MECHANISM COMPRISING A REVOLVING TUBULAR AGITATOR AR, EQUIPPED WITH NOZZLES WHICH ARE SPACED LONGITUDINALLY OF SAID ARM, SAID AGITATOR ARM BEING MOUNTED IN A HORIZONTAL PLANE NEAR THE TOP OF THE FILTER BED, A SOURCE OF WASH WASTER UNDER PRESSURE CONNECTED TO SAID AGITATOR ARM TO CAUSE HIGH VELOCITY JETS OF WATER OF DISCHARGE FROM SAID NOZZLES, ALTERNATE ONES OF SAID NOZZLES FORMING A FIRST GROUP THEREOF BEING ARRANGED TO DELIVER JETS OF WASH WATER UPWARDLY FROM A HORIZONTAL PLANE IN SAID FILTER BED AND AT A SMALL ANGLE TO THE HORIZONTAL, AND OTHERS OF SAID NOZZLES BETWEEN AND ADJACENT THE NOZZLES OF SAID FIRST GROUP AND FORMING A SECOND GROUP THEREOF BEING ARRANGED TO DELIVER JETS OF WASH WATER DOWNWARDLY FROM A HORIZONTAL PLANE IN SAID BED AT A SMALL ANGLE TO THE HORIZONTAL WHEREBY A SUBSTANTIAL DEPTH OF THE FILTER BED IS AGITATED AND WASHED WITH HIGH VELOCITY JET STREAMS OF WATER DIRECTED AT DIFFERENT ANGLES WITH RESPECT TO A HORIZONTAL PLANE.