Patent ID: 7927432

Claim:
A cleaning head for mounting inside a tank, said cleaning head comprising: a turbine driven by a source of pressure liquid passing thereby for causing rotation thereof, a gear rotatably driven by said turbine, rotation of said gear causing a gear housing and a hub, mounted thereon and having nozzles, to rotate, said liquid being conveyed from the turbine to the nozzles without entering the gear housing, said gear housing being mounted on a stationary mounting part so that the liquid from the turbine bypasses the gear housing and flows to the nozzles, and a magnetic hysteresis coupling for magnetically transferring the rotation of the turbine to an input shaft of the gear, the magnetic hysteresis coupling having two coupling parts, a magnetic drive coupling part disposed outside the gear housing, and a driven hysteresis coupling part disposed inside the gear housing, a partition physically separating the magnetic drive coupling part, located outside the gear housing and within the flow of liquid flowing to the nozzles, from the driven hysteresis coupling part, located within the gear housing and out of contact with the liquid flow, rotation of the turbine ( 3 ) being transferred to the gear in the gear housing ( 13 ) via the magnetic hysteresis coupling which comprises a magnetic inductor drive coupling part ( 9 ) disposed in a liquid space in which the turbine ( 3 ) is driven, and being connected thereto and rotated thereby, the magnetic inductor drive coupling part ( 9 ) only magnetically engaging and driving the driven hysteresis coupling part ( 11 ) which is mounted in the gear housing ( 13 ), and which is connected with the input shaft ( 12 ) of the gear.