# US 8,540,789 B2 · Filter element constructions > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,540,789 B2 - Document ID: US8540789B2 - Status: Granted - Kind: B2 - Application number: 12/673,880 - Filed: 2008-08-22 - Published: 2011-03-17 - Granted: 2013-09-24 - Earliest claimed: 2007-08-25 - Assignees: Madison Filter 981 Limited - Applicants: Niels Fischer - Inventors: Niels Fischer - Web page: https://patentgrep.com/patent/US8540789B2 ## CPC - B01D 46/2414: {End caps including additional functions or special forms} - B01D 46/0001: {Making filtering elements} - B01D 2265/06: Details of supporting structures for filtering material, e.g. cores - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) ## Abstract A filter element comprises a pleated filter (10), one end of which is received in an end cap (11), which is made up of a unitary molding comprising an end part (21) of a harder plastics material, and a lower part (22) of a softer plastics material, the plastics being compatible or of the same composition, differing only in hardness. A groove (24) engages with a support plate (14), the groove being formed in the softer material abutting the harder material so that the latter forms one face of the groove. A perforated support sleeve (29) can be inserted by dropping into the filter, and an end cap (12) at the other end of the filter either closes the end or is adapted for connection to a further similar filter. ## Claims ### Claim 1 A filter element, comprising: a filter body of pleated filter material, and an end cap adapted to provide dimensional stability to the filter body and to engage a circumferential edge of an aperture in a support plate within a radially outwardly facing circumferential groove in the end cap, the end cap comprising a unitary body formed by molding from two plastics compositions of compatible composition, wherein the end cap comprises a molding having a first part consisting of plastics having a first hardness, and a second part consisting of plastics having a second lower hardness, wherein the groove is provided in the second part having the lower hardness immediately adjacent the first part, such that an upper or lower all of the groove is of the harder material. ### Claim 2 (depends on 1) A filter element according to claim 1, wherein the first part of the end cap comprises an end part or flange having the first or higher hardness, and a skirt part of the second or lower hardness, said skirt part including the inner end and lower wall of the groove, the filter element thereby being adapted for insertion into the support plate. ### Claim 3 (depends on 2) A filter element according to claim 2, wherein the groove is formed in the skirt part immediately adjacent the harder end part or flange, so that a wall of the groove adjacent the end part or flange is of the harder material. ### Claim 4 (depends on 3) A filter element according to claim 3, wherein the end cap is provided with an inner edge which is formed with a saw-toothed profile matching the pleats of the filter medium. ### Claim 5 (depends on 2) A filter element according to claim 2, wherein one or more slots are provided in the upper flange to aid insertion of a removing tool. ### Claim 6 (depends on 1) A filter element according to claim 1, further comprising: a rigid mesh cylindrical cage which can be inserted freely within the filter element, so that it can be dropped in from the upper end to act as a support for the filter material. ### Claim 7 (depends on 1) A filter element according to claim 1, wherein the width of the second part is of larger radius than the width of an aperture in a support plate in which it fits, so that the softer plastics material is maintained under compression to provide a good seal. ### Claim 8 (depends on 1) A filter element according to claim 1, further comprising: a base molding is provided at the opposite end of the filter element, and is of the harder polymer hardness used in the end cap. ### Claim 9 (depends on 8) A filter element according to claim 8, herein the base molding comprises a cap on the respective end of the filter element which closes the end to ensure that gases only pass through the filter material radially from outside to inside, or vice versa. ### Claim 10 (depends on 8) A filter element according to claim 8, wherein the base molding provides an axial opening and is adapted for connection to a further filter element, so that two or more filter elements may be fitted together end to end in modular fashion to provide a filter structure of any desired length. ### Claim 11 (depends on 1) A filter element according to claim 1, wherein polymer materials used to form the end cap are selected from plastic or thermoplastic elastomers. ### Claim 12 (depends on 1) A filter element according to claim 1, wherein polymer materials used to form the end cap are selected from a group consisting of: thermosetting polymers, polyurethanes, and polyalkenes. ### Claim 13 (depends on 12) A filter element according to claim 12, wherein the polymer materials used to form the end cap are selected from a group consisting of: polyethylene and polypropylene, polyesters, acrylonitrile butadiene styrene (ABS), and epoxys. ### Claim 14 (depends on 1) A filter element according to claim 1, wherein the first part of the end cap comprises a skirt part of the first or higher hardness, and the second part of the end cap comprises an end part or flange having the second lower hardness, said flange including the inner end and lower wall of the groove, the filter element thereby being adapted for insertion into the support plate. ### Claim 15 (depends on 14) A filter element according to claim 14, wherein the groove is formed in the flange immediately adjacent the harder skirt part, so that a wall of the groove adjacent the skirt part is of the harder material. ### Claim 16 A filter element comprising a filter body of pleated filter material, and an end cap adapted to provide dimensional stability to the filter body and to engage with a circumferential edge of an aperture in a support plate by means of a radially outwardly facing circumferential groove in the end cap, the end cap comprising a unitary body formed by molding from two plastics compositions of compatible composition, the end cap comprising a molding having a first part consisting of plastics having a first hardness, and a second part consisting of plastics having a second lower hardness, wherein the groove is provided wholly in the part having the lower hardness immediately adjacent the harder part. ### Claim 17 (depends on 16) A filter element according to claim 16 wherein the end cap comprises an end part or flange having the higher degree of hardness, and a lower part of the lower degree of hardness, said lower part including the groove, the filter element thereby being adapted for insertion into the support plate from above. ### Claim 18 (depends on 16) A filter element according to claim 16 wherein the end cap comprises an end part or upper flange having the lower degree of hardness and a lower part of the higher degree of hardness, the upper part including the groove, the filter element thereby being adapted for insertion into the support plate from below. ### Claim 19 A filter element, comprising: a filter body of pleated filter material having an upper end, and an end cap at the upper end of said filter body, said end cap being adapted to provide dimensional stability to the filter body, said end cap comprising a unitary molded body formed by molding from two plastics compositions of compatible composition, said end cap having a first part consisting of plastics having a first hardness, and a second part consisting of plastics having a second lower hardness, said end cap including a radially outwardly facing circumferential groove provided in the second part having the lower hardness immediately adjacent the first part, such that an upper or lower wall of the groove is of the harder material, said radially outwardly facing grove being configured and arranged to engage a circumferential inner edge of an aperture in a filter support plate. ### Claim 20 (depends on 19) The filter element of claim 19 wherein the end cap comprises an upper flange part having the higher degree of hardness, and a lower skirt part of the lower degree of hardness, said lower skirt part including the groove, the filter element thereby being adapted for insertion into the aperture in the support plate from above. ### Claim 21 (depends on 19) The filter element of claim 19 wherein the end cap comprises an upper skirt part having the lower degree of hardness and a lower flange part of the higher degree of hardness, the upper skirt part including the groove, the filter element thereby being adapted for insertion into the aperture in the support plate from below.