Abstract: Embodiments of a filter cartridge for a sports bottle are shown and described. Each embodiment has a member for containing or attaching to a filter media and having a means of securing the cartridge inside the bottle neck without requiring modification of the bottle or bottle cap. The preferred cartridge includes a generally cylindrical cup or ring for holding media, and an extension that fits between the cap and the bottle neck to secure the cartridge in place while preserving a water-tight seal. The extension has a slanted inner surface that diverts the cap's knife edge inward slightly and then seals with the outside surface of the knife blade. As the cap is installed and the knife presses down against the extension, the knife forces the expandable or flexible extension outward slightly to seal against the neck.

Abstract: Embodiments of a fluid filtering assembly are shown and described, each embodiment including a valve head that routes fluid to and from a filter cartridge and that includes a valve system that automatically opens and closes when the filter cartridge is inserted and removed, respectively. The valve system preferably includes a generally-cylindrical piston with a hollow interior space, which receives a stem member. The stem member has a bottom-end seat or sealing member and has a central body shape that allows fluid to flow up through the piston interior space, either through or up around the stem member. Upon removal of the filter cartridge, the piston is biased to move down into an "off" position, to close both the inlet and outlet fluid passages. In this "off" position, the piston exterior surface blocks off radial fluid inlets and the piston interior surface seals with the stem bottom end seat to prevent fluid backflow out of the piston interior space.

Abstract: Embodiments of a fluid filtering assembly are shown and described, each embodiment including a valve head that routes fluid to and from a filter cartridge and that includes a valve system that automatically opens and closes when the filter cartridge is inserted and removed, respectively. The valve system preferably includes a generally-cylindrical piston with a hollow interior space, which receives a stem member. The stem member has a bottom-end seat or sealing member and has a central body shape that allows fluid to flow up through the piston interior space, either through or up around the stem member. Upon removal of the filter cartridge, the piston is biased to move down into an "off" position, to close both the inlet and outlet fluid passages. In this "off" position, the piston exterior surface blocks off radial fluid inlets and the piston interior surface seals with the stem bottom end seat to prevent fluid backflow out of the piston interior space.

Abstract: Double flow-through filtration apparatus requiring the bulk of the water to be treated to twice flow through filtering media contained within a filter housing. The housing includes an inlet port for receiving water from a source; a combination port for water flow to and from a storage tank and an outlet port which may lead to a water tap. Untreated water from a source flows into the filter housing through the inlet port. A cup type check valve prevents flow directly to the storage tank, forcing the water through the filter media for a first treatment. A filter tube, extending through the media, in cooperation with a check valve of the slip type, permits once treated water to flow to a storage tank and prevents backflow into the tube. Once the water tap is opened, the once treated water flows form the storage tank, through the combination port, by the cup valve, and through the filter media a second time before exiting the outlet port of the housing and the tap.

Abstract: Water filtration apparatus with an internal by-pass for conducting water from a water source to a storage tank and from the storage tank through filter media to a tap. The apparatus includes a filter housing with an inlet port, and outlet port, and a combination inlet-outlet port connected to the storage tank. Water from the source flows slowly into the filter housing through the inlet port and through the combination port to the tank. Once the tap is opened, water flows from the storage tank, through the filter media, out the outlet port and out of the tap.

Abstract: Multiple embodiments of a filter cartridge are disclosed, the cartridge preferably being adapted for use within a housing and including a tubular outer wall element with closures at either end, one of the closures being of unitary construction and comprising an annular ring portion for attachment to the tubular element and axially central portion. Flexible spring elements interconnect the central portion with the annular ring while being adapted for flexure into a stressed condition for urging permeable membrane portions within the ring against a filter medium contained within the cartridge for producing and maintaining a compacting force on the filter medium. Preferably, the unitary end closure cooperates with the tubular wall element and the other closure as well as with portions of the housing for assuring proper fluid flow through the filter medium.