초록 ▼

A pleated paper filter element (10) has a fluid-permeable foamed-plastic shield (16) formed on one of its faces to firmly and accurately position the adjacent folds of filter media. The shield (16) is formed in situ and bonds to the filter media without the use of an intermediate adhesive so as to f

A pleated paper filter element (10) has a fluid-permeable foamed-plastic shield (16) formed on one of its faces to firmly and accurately position the adjacent folds of filter media. The shield (16) is formed in situ and bonds to the filter media without the use of an intermediate adhesive so as to form a unitary structure. A method of making such a filter involves disposing a foamable liquid plastic (34) near a pleated paper filter unit and foaming the plastic. Prior to solidification, the plastic is effective to bond directly to the filter media. A mold (22) for making such a filter element includes a receptacle (28) for receiving a quantity of liquid plastic and a filter unit and for holding them in the proper relation while the plastic is foamed. The mold receptacle includes projections (30) which form perforations (18) in the solidified plastic and which provide for fluid flow communication through the filter element. The plastic may be of the open-cell fluid-permeable type to permit fluid flow communication through the shield to the filter element.

대표청구항 ▼

An integral filter element comprising: a sheet of filtering media, said filtering media sheet having a multiplicity of substantially parallel elongated folds therein, said folds being successively disposed in opposite directions to provide a plurality of elongated V-shaped pleats in said filtering m

An integral filter element comprising: a sheet of filtering media, said filtering media sheet having a multiplicity of substantially parallel elongated folds therein, said folds being successively disposed in opposite directions to provide a plurality of elongated V-shaped pleats in said filtering media sheet, said pleats defining like-disposed folds, said sheet being joined at its ends and rolled to define an annular filter having inner and outer diameters with its pleats parallel to the axis of the annulus so that the pleats define inner and outer apexes at respectively the inner and outer diameters of said annular filter; and a fluid-permeable, shape-retaining, structurally self-supporting shield circumscribing the outside of said annular filter and integrally bonded to the like-disposed folds of said filtering media sheet, said shield being formed of a shape-retaining, structurally self-supporting, fluid permeable cellular plastic and laterally extending from one like-disposed fold to the next adjacent like-disposed fold so as to space apart said folds, said shield further extending longitudinally along said like-disposed folds and providing a substantially continuous bond between said shield and said like-disposed folds to restrain like-disposed folds from movement relative to said shield, said bond being formed by partially embedding the outer apex of each V-shaped pleat into said shield during the transition of the shield from a foamed liquid to said shape-retaining solid, the portion of each pleat between the inner and outer apexes thereof being unsupported by said shield.