# US RE50,860 E1 · Filter with variable cross-section axial seal > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US RE50,860 E1 - Document ID: USRE50860E1 - Status: Granted - Kind: E1 - Application number: 18/140,773 - Filed: 2023-04-28 - Granted: 2026-04-14 - Earliest claimed: 2015-12-11 - Assignees: Atmus Filtration IP Inc. - Applicants: Cummins Filtration IP, Inc. - Inventors: Ken Tofsland - Web page: https://patentgrep.com/patent/USRE50860E1 ## CPC - B01D 46/2411: {Filter cartridges} - B01D 35/30: Filter housing constructions - B01D 46/0005: {Mounting of filtering elements within casings, housings or frames (B01D46/2422 takes precedence)} - B01D 2279/60: for the intake of internal combustion engines or turbines - F02M 35/02416: {Fixing, mounting, supporting or arranging filter elements; Filter element cartridges} - 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) - F02M: SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF ## Abstract Filtration systems having filter elements having an axial seal member with a variable cross-section are described. The variable cross-section is matched by the non-planar sealing surfaces of the housing and housing cover that receive the filter elements. The non-planar sealing surfaces of the housing and the housing cover prevent proper filtration system function when an unauthorized replacement filter element having a flat axial seal member is installed in the housing. ## Claims ### Claim 1 A filtration system, comprising: a housing defining a central compartment therein, the housing including an outlet and a housing sealing surface, the housing sealing surface being non-planar; a cover removably coupled to the housing, the cover including an inlet and a cover sealing surface; and a filter element positioned within the central compartment of the housing, the filter element including filter media and a seal member coupled to the filter media and circumscribing at least a portion of the filter media, the seal member including a first sealing surface and a second sealing surface, the first sealing surface has an arc-shaped profile extending from a first end of the seal member to a second end of the seal member, the second sealing surface has an opposite arc-shaped profile extending from the first end of the seal member to the second end of the seal member, each arc-shaped profile defines a convex arc shape comprising a continuous curve between the first end and the second end, the seal member having a variable cross-section such that, at a perimetral distance from the filter media, an axial distance between the first sealing surface and the second sealing surface varies along at least a portion of the seal member, the variable cross-section being complementary to the housing sealing surface and the cover sealing surface such that the seal member forms an axial seal between the housing and the cover when the filter element is installed in the air filtration system. ### Claim 2 (depends on 1) The filtration system of claim 1, wherein each arc-shaped profile has a height that is smaller than a span distance such that a ratio of the span distance to the height is greater than 10 to 1. ### Claim 3 (depends on 2) The filtration system of claim 2, wherein the ratio of the span distance to the height is greater than 50 to 1. ### Claim 4 (depends on 2) The filtration system of claim 2, wherein the opposite arc-shaped profile extends the span distance and has the height that is smaller than the span distance. ### Claim 5 (depends on 4) The filtration system of claim 4, wherein the cover sealing surface is non-planar. ### Claim 6 (depends on 1) The filtration system of claim 1, wherein the filter element is a cylindrical filter element, and wherein the seal member is ring shaped. ### Claim 7 (depends on 1) The filtration system of claim 1, wherein the seal member is substantially rectangular in shape. ### Claim 8 (depends on 1) The filtration system of claim 1, and wherein the distance between the first sealing surface and the second sealing surface varies along only one of four sides of the seal member. ### Claim 9 (depends on 1) The filtration system of claim 1, and wherein the distance between the first sealing surface and the second sealing surface varies along at least two of four sides of the seal member. ### Claim 10 (depends on 1) The filtration system of claim 1, wherein the first sealing surface and the second sealing surface are on opposing sides of the seal member. ### Claim 11 A filter element comprising: filter media; and a seal member coupled to the filter media and circumscribing at least a portion of the filter media, the seal member comprising a first sealing surface and a second sealing surface, the first sealing surface has an arc-shaped profile extending from a first end of the seal member to a second end of the seal member, the second sealing surface has an opposite arc-shaped profile extending from the first end of the seal member to the second end of the seal member, each arc-shaped profile defines a convex arc shape comprising a continuous curve between the first end and the second end, the seal member having a variable cross-section such that, at a perimetral distance from the filter media, an axial distance between the first sealing surface and the second sealing surface varies along at least a portion of the seal member. ### Claim 12 (depends on 11) The filter element of claim 11, wherein each arc-shaped profile has a height that is smaller than a span distance such that a ratio of the span distance to the height is greater than 10 to 1. ### Claim 13 (depends on 12) The filter element of claim 12, wherein the ratio of the span distance to the height is greater than 50 to 1. ### Claim 14 (depends on 12) The filter element of claim 12, wherein the opposite arc-shaped profile extends the span distance and has the height that is smaller than the span distance. ### Claim 15 (depends on 14) The filter element of claim 14, wherein the cover sealing surface is non-planar. ### Claim 16 (depends on 11) The filter element of claim 11, wherein the filter element is a cylindrical filter element, and wherein the seal member is ring shaped. ### Claim 17 (depends on 11) The filter element of claim 11, wherein the seal member is substantially rectangular in shape. ### Claim 18 (depends on 11) The filter element of claim 11, and wherein the distance between the first sealing surface and the second sealing surface varies along only one of four sides of the seal member. ### Claim 19 (depends on 11) The filter element of claim 11, and wherein the distance between the first sealing surface and the second sealing surface varies along at least two of four sides of the seal member. ### Claim 20 (depends on 11) The filter element of claim 11, wherein the first sealing surface and the second sealing surface are on opposing sides of the seal member.