Abstract: A filter jug for purifying water for domestic use comprises a container (2) divided at least into a first compartment (8) and a second compartment (9) intercommunicating through a filter cartridge (11), and a first duct (12) and a second duct (13) for the admission and for the discharge of the water to the first compartment and from the second compartment (8, 9), respectively. Flow-measuring means (15) and counting means (14, 14a, 14b), associated therewith, are provided in the jug in at least one of the ducts (12, 13), for determining the total quantity of water treated by the filter cartridge (11) so as to identify the reaching of a limit quantity above which the cartridge should be considered exhausted.

Abstract: In a device for shutting off the flow of a fluid through a duct, preferably in a system for filtering drinking water, means for shutting off the duct comprise at least one obturator (14,22,35,43) disposed over a corresponding orifice (11) of the duct and means (15,23,36) for restraining the obturator (14,22,35,43) in a position such that the corresponding orifice (11) is not shut off, the restraining means being exposed to the flow of fluid through the duct and being able to undergo a change of state consequent upon the period of exposure to the flow in order to release the obturator (14,22,35) so that it shuts off the duct after a predetermined flow of fluid has taken place through the duct.

Abstract: A vessel for filtering liquids includes a container and a receptacle for the liquid to be filtered, with a filtering device between the receptacle and the container. A lid is removably fitted to the container for the purpose of easy access to the container. A counting device is associated with the lid and is automatically activated by the removal of the lid for detecting and counting the occasions on which access is gained to the container by removing the lid.