A water filter system includes a removable filter unit having a body portion including a proximal end and a distal end. The proximal end is adapted to be inserted into a filter head assembly. A laterally extending key member is disposed on the body portion and adapted to engage a key slot in the filter head assembly. An engagement protrusion extends from the proximal end. The engagement protrusion includes a first portion that has a first radius of curvature and a second portion opposing the first portion that includes a second radius of curvature that is larger than the first radius of curvature.

A filter assembly includes a cylindrical filter housing, a filter element housing plate positioned between a high pressure and a low pressure side of the filter housing, the filter element housing plate having a plurality of one female cavities, and a plurality of replaceable filter elements within the filter housing. Each replaceable filter element has an endcap with an external rounded polygon shaped sealing surface engaging peripheral surfaces of an associated female cavity of the filter element housing plate and sealing against peripheral surfaces of the female cavity of the filter element housing plate.

A filter apparatus has a filter housing (1) accommodating at least one filter element (17) having an inner filter cavity (23) enclosed by a filter medium (27). The housing (1) contains an element bolder (19) that interacts with the filter element (17) located in its functional position. The element holder (19) has a projecting accommodating part (43) with an outer configuration adapted to the shape of an opening (37) located at the end of the filter element (17) to be secured to the element holder (19). The accommodating part (43) fits through the opening (37) of the filter element (17) located in the functional position.

A filter device includes a device housing (2) removably accommodating a filter element (26) with an element material (28) extending between two end members (32, 34). One end member (34) has a wall member (46) of a polygonal shape inserted into an accommodating space (66) of an accommodating member (36) attached to the device housing (2). The accommodating member (36) also has a polygon-shaped wall member (68). The wall members are disposed adjacent and facing each other in an accommodating state. The accommodating space (66) is delimited outwards by its wall member (68) with a polygonal shape. A further wall member (70) with a circular shape delimits the accommodating space (66) to the inside and passes through a circular transfer space (76) in the adjacently disposed end member (34).

The invention provides a filtration system with a rotating core driving thimble opening and closing water passage, comprising a casing, a filter and a connector, wherein the filter and the connector are connected and fixed in an inner cavity of the casing, the casing consists of an upper cover of the casing and a lower cover of the casing, which are connected via a connecting member; a connector core of the present invention has a groove and a boss thereon, the connector core, a water intake thimble and a water outtake thimble are tightly pressed by a spring, when the connector is rotated, the water intake thimble and the water outtake thimbles are raised from the position of the groove to the position of the boss, and the water passage is opened. When disassembled, the connector is lowered from the position of the boss to the position of the groove, and the water passage is closed, preventing the leakage of the connector water due to the removal of a filter element. Due to the action of the spring, even if the water intake thimble and the water outtake thimble are worn seriously, the water intake sealing ring and the water outtake thimble sealing ring is attached to a water intake thimble sleeve and a water outtake thimble sleeve, realizing the sealing and not causing the leakage phenomenon.

An adaptor device for retrofitting in a filter housing is disclosed. The adaptor device allows the filter to be retrofitted with a plurality of filter elements, thereby improving its filtering efficiency.

Various embodiments relate to a filter element. The filter element includes a first endplate that defines a first endplate opening and a second endplate. Filter media is positioned between and extending axially between the first endplate and the second endplate. The filter media defines a central opening extending axially therein. A support structure is disposed within the central opening of the filter media and is attached to the first endplate and the second endplate. The support structure includes an axial lobed extension that extends from a first end of the support structure to a second end of the support structure. The support structure is configured to resist collapse of the filter element.

A filtration system with a rotating core driving thimble opening and closing water passage, including: a casing, a filter and a connector, wherein the filter and the connector are connected and fixed in the casing; the filter includes a filter element body and a carbon rod; the connector includes a connector core, a water intake thimble, a water outtake thimble; the connector core is provided with a water inlet boss on which a first arc groove is provided, and a water outlet boss on which a second arc groove is provided; the water intake thimble and the water outtake thimble are lifted and falls through the rotation of the connector core, so that a water intake passage and a water outtake passage are opened and closed.

A membrane casing that watertightly houses a membrane element for filtering raw water includes a tubular casing main body, a lid body, and a pressing mechanism. The casing main body houses a membrane element. The lid body fits an opening end of the casing main body and is movable in the axial direction of the casing main body while maintaining the attitude and while securing watertightness with the casing main body. The pressing mechanism and presses the lid body to press and hold the membrane element housed in the casing main body. The membrane casing has a simple configuration capable of watertightly securing using a predetermined pressing force by accommodating variations in size of the membrane element, even if the membrane casing cannot be formed into a cylindrical shape.

A filter for gravity-fed applications, having filter media with a hollow center, the filter being generally prone to a degradation or cessation in fluid flow due to air entrapment or air lock within the filter housing cavity, which develops during filtering. A diffuser element is introduced to pierce the entrapped air bubble, the diffuser element being an elongated structure connected to the filter housing top end cap and extending through the entrapped air bubble to the filter media.