Abstract: A floating self-propelled cleaning device (10) for water surfaces, in particular swimming pools, comprises a central floating body (11) and two side floating elements (12) to it connected at opposite sides by two arms (14) to which two net-shaped collecting containers (13) are fastened. The net-shaped containers (13) have openings (17) that allow the inlet of impurities, but prevent the outlet thereof during possible stops or under the action of waves that can occur during the travel on the water surface. The floating device (10) is driven by propelling means (20) and (30) that substantially cause the side floating elements (12) to rotate about an instantaneous centre of rotation located approximately at the central body (11). The rotation of the side floating elements (12) is associated to a shifting movement caused by at least a distribution element (15) movable with respect to the floating body (10).

Abstract: A floating self-propelled cleaning device (10) for water surfaces, in particular swimming pools, comprises a central floating body (11) and two side floating elements (12) to it connected at opposite sides by two arms (14) to which two net-shaped collecting containers (13) are fastened. The net-shaped containers (13) have openings (17) that allow the inlet of impurities, but prevent the outlet thereof during possible stops or under the action of waves that can occur during the travel on the water surface. The floating device (10) is driven by propelling means (20) and (30) that substantially cause the side floating elements (12) to rotate about an instantaneous centre of rotation located approximately at the central body (11). The rotation of the side floating elements (12) is associated to a shifting movement caused by at least a distribution element (15) movable with respect to the floating body (10).

Abstract: An apparatus for on/off controlling a pump in a water distribution network, which ensures a practically constant pressure through the distribution network, comprises, within a body, a chamber having an inlet conduit adapted for connection to the delivery side of the pump and an outlet conduit adapted for connection to the network, a pressure switch placed in said chamber to issue a start signal to the pump at a predetermined pressure setting, and a flow switch placed in the outlet conduit to issue a start signal to the pump upon the occurrence of a predetermined minimum flow or a stop signal to the pump in the event of the flow being interrupted.