A filtration system includes a filter housing having a cavity and a base, a drain defined in the base, a channel defined in the base and in fluid communication with the drain, and a filter cartridge having a longitudinal axis and being movable between an installed position within the cavity of the filter housing and an uninstalled position outside the cavity of the filter housing. The channel defines an outer diameter. The filter cartridge includes a bottom endplate defining an outer diameter that is greater than the outer diameter of the channel so that, in the installed position, the bottom endplate covers the channel and prevents fluid flow from the cavity to the drain, and a filter media extending axially outwardly from the bottom endplate.

A backflow-preventing filter module includes a filter unit and a backflow-prevention valve. The filter unit includes a filter cartridge that has a connector formed with an annular groove, and a filter shell that defines an accommodating space and that includes a connecting head. The connecting head has an inner surrounding wall defining an annular slot. The backflow-prevention valve is sleeved on the connector, and has a fixing portion disposed in the annular groove and an abutting portion moveable between an open position, where a distal end of the abutting portion is pushed by water to be away from the inner surrounding wall so that the annular slot is not blocked, and a closed position, where the abutting portion is expanded to abut the distal end thereof against the inner surrounding wall, thereby blocking the annular slot.

A fluid filter having a filter canister, a fluid inlet, a fluid outlet, filter media, and a pressure sensitive valve assembly is described. The pressure sensitive valve assembly comprises an orifice surround, a pressure relief spring, and a valve plug comprising a valve head and first and second retention legs. The first and second retention legs of the valve plug are spaced apart from one another, extend from a leg base positioned at the sealing side of the valve head to a distal end of the retention leg, and comprise respective seating regions, tapered transition regions, and clearance regions. Each of the respective seating regions comprises a spring engaging hook structurally configured to receive a seating portion of the pressure relief spring. The pressure relief spring is compressed between the orifice surround and the spring engaging hooks to bias the pressure sensitive valve assembly towards the closed state.

A filter cartridge for operatively engaging a spool valve manifold having an ejection cam and an insertion cam. The filter cartridge includes a filter element and inlet/outlet portion in fluid communication with the filter element.

A fluid filter having a filter canister, a fluid inlet, a fluid outlet, filter media, and a pressure sensitive valve assembly is described. The pressure sensitive valve assembly comprises an orifice surround, a pressure relief spring, and a valve plug comprising a valve head and first and second retention legs. The first and second retention legs of the valve plug are spaced apart from one another, extend from a leg base positioned at the sealing side of the valve head to a distal end of the retention leg, and comprise respective seating regions, tapered transition regions, and clearance regions. Each of the respective seating regions comprises a spring engaging hook structurally configured to receive a seating portion of the pressure relief spring. The pressure relief spring is compressed between the orifice surround and the spring engaging hooks to bias the pressure sensitive valve assembly towards the closed state.

A fluid treatment cartridge includes a housing having a fluid inlet and a fluid outlet with a treatment media contained within the housing. The fluid treatment cartridge includes a detection member comprising at least one closed electrically conductive loop having at least two spatially separate sections. Each of the sections generates a magnetic response when at least one section is electromagnetically excited. The magnetic response of each section is predetermined by the physical shape of the section and comprises at least one of a predetermined magnetic phase response and a predetermined magnetic amplitude response. The predetermined magnetic response of at least one other section of the closed electrically conductive loop corresponds to at least a one digit code.

A fluid treatment cartridge includes a housing having a fluid inlet and a fluid outlet with a treatment media contained within the housing. The fluid treatment cartridge includes a detection member comprising at least one closed electrically conductive loop having at least two spatially separate sections. Each of the sections generates a magnetic response when at least one section is electromagnetically excited. The magnetic response of each section is predetermined by the physical shape of the section and comprises at least one of a predetermined magnetic phase response and a predetermined magnetic amplitude response. The predetermined magnetic response of at least one other section of the closed electrically conductive loop corresponds to at least a one digit code.

A water stoppage structure utilized in a water purifier filter core, comprising a filter core main body, provided with a water input port, a first water output port, and a second water output port; a filter core, disposed in the filter core main body; a seat body, disposed at one end of the filter core main body, matching and working in cooperation with the water input port, the first water output port, and the second water output port of the filter core main body; a first check valve, disposed at the water import port, and on a water channel leading to the filter core main body, for allowing water to pass only through the filter core main body; a first water passage switch valve, disposed on the second water output port; and a second water passage switch valve, disposed on the first water output port.

A filter cartridge for operatively engaging a manifold having an ejection cam and an insertion cam. The filter cartridge includes a filter element and inlet/outlet portion in fluid communication with the filter element.

A water filter with alarm function for indicating blockage of a filter cartridge thereof and an alarm method are provided. The filter main body is provided with a filter cartridge and is arranged with a before-filtering water cavity. A filter upper cover covers the top of the filter main body. The before-filtering water cavity is accommodated with a floating-ball-type indicating apparatus, which comprises a floating ball, a connecting rod and a color scale. The connecting rod is mounted rotatably on an inner surface of the filter upper cover with the aid of a hinge support. The floating ball is arranged at the front end of the connecting rod. The color scale is also arranged on the connecting rod. A transparent visual cover that matches with the color scale is arranged on the upper surface of the filter upper cover.