# US 10,482,928 B2 · Recirculation filter for an electronic enclosure > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,482,928 B2 - Document ID: US10482928B2 - Status: Granted - Kind: B2 - Application number: 15/118,410 - Filed: 2015-02-12 - Published: 2017-06-22 - Granted: 2019-11-19 - Earliest claimed: 2014-02-13 - Assignees: Donaldson Company, Inc. - Applicants: Donaldson Company, Inc. - Inventors: Stanley B. Miller, III; Allen N. Nicklay; Christopher J. Fischer; Daniel L. Tuma - Web page: https://patentgrep.com/patent/US10482928B2 ## CPC - G11B 33/146: {constructional details of filters} - B01D 24/008: {arranged concentrically or coaxially} - B01D 39/1607: {the material being fibrous (B01D39/18 takes precedence)} - B01D 39/2058: {the material being particulate} - B01J 20/20: comprising free carbon; comprising carbon obtained by carbonising processes - B01D 39/00: Filtering material for liquid or gaseous fluids - B01D 2239/1258: Permeability - B01D 2253/00: Adsorbents used in seperation treatment of gases and vapours - B01D 2279/45: for electronic devices, e.g. computers, hard-discs, mobile phones - G11B 33/14: Reducing influence of physical parameters, e.g. temperature change, moisture, dust - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) - 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) - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS ## Abstract The technology disclosed herein relates to filter assemblies and methods of making filter assemblies. One filter assembly has a first sheet of filter media having a first perimeter region and a second sheet of filter media having a second perimeter region. The first perimeter region and the second perimeter region are bonded in a rim region. A plurality of adsorbent beads are disposed between the first sheet of filter media and the second sheet of filter media, and a substantial portion of the plurality of adsorbent beads are unbonded. Other embodiments are also described. ## Claims ### Claim 1 A filter assembly comprising: a first sheet of filter media having a first perimeter region; a second sheet of filter media having a second perimeter region, wherein the first perimeter region and the second perimeter region are bonded in a rim region; and a plurality of adsorbent beads disposed between the first sheet of filter media and the second sheet of filter media, wherein a substantial portion of the plurality of adsorbent beads are unbonded and the plurality of adsorbent beads define an adsorbent face area having an adsorbent density of greater than 600 g/m2. ### Claim 2 (depends on 1) The filter assembly of claim 1, further comprising a first support layer coupled to the first sheet of filter media, wherein the first support layer has a permeability of between about 100 ft./min. at 0.5 inches of water and about 800 ft./min. at 0.5 inches of water. ### Claim 3 (depends on 1) The filter assembly of claim 1, wherein the first sheet of filter media defines a substantially self-supporting cavity. ### Claim 4 (depends on 1) The filter assembly of claim 1, wherein the second sheet of filter media is substantially planar. ### Claim 5 (depends on 1) The filter assembly of claim 1, wherein the second sheet of filter media comprises a screen. ### Claim 6 (depends on 1) The filter assembly of claim 1, wherein the plurality of adsorbent beads comprises activated carbon beads. ### Claim 7 (depends on 1) The filter assembly of claim 1, wherein the second sheet of filter media is the same material as the first sheet of filter media. ### Claim 8 (depends on 1) The filter assembly of claim 1, wherein the rim region defines a weld area. ### Claim 9 (depends on 1) The filter assembly of claim 1, wherein all of the plurality of adsorbent beads are completely unbonded. ### Claim 10 (depends on 1) The filter assembly of claim 1, wherein the first sheet of filter media has a permeability of between about 250 ft./min. at 0.5 inches of water and about 750 ft./min. at 0.5 inches of water. ### Claim 11 (depends on 1) The filter assembly of claim 1, wherein the first sheet of filter media has a figure of merit greater than about 60, wherein the figure of merit is calculated based upon a fractional efficiency determined for particles having a size of 0.3 μm in an air flow having a velocity of 10.5 ft./min. and a Frazier permeability at 0.5 inches H2O. ### Claim 12 (depends on 1) The filter assembly of claim 1, wherein the rim region extends about the entire perimeter of the first sheet of filter media and the second sheet of filter media. ### Claim 13 (depends on 1) The filter assembly of claim 1, having a perimeter that defines a fold along a portion of the perimeter of the filter assembly. ### Claim 14 (depends on 1) A disk drive assembly, the disk drive assembly comprising: (a) a disk drive housing that defines an enclosure; (b) at least one disk rotatably mounted within the enclosure, wherein rotation of the at least one disk induces airflow within the enclosure; and (c) a filter assembly of claim 1 disposed within the enclosure. ### Claim 15 (depends on 14) The disk drive assembly of claim 14, wherein filter assembly is disposed within the enclosure such that the second sheet of filter media is the flow face of the filter assembly. ### Claim 16 A method of making a filter assembly comprising: placing a first sheet of filter media between a first mating structure and a second mating structure, wherein the first mating structure defines a perimeter and a cavity recessed from the perimeter and the second mating structure defines a protrusion configured for mating engagement with the cavity; compressing the first sheet of filter media between the first mating structure and the second mating structure such that the first sheet of filter media defines and retains a cavity structure and a rim region about the perimeter of the cavity; disposing a plurality of adsorbent beads within the cavity of the first sheet of filter media, such that a substantial portion of the plurality of adsorbent beads are unbonded where the plurality of adsorbent beads define an adsorbent face area having an adsorbent density of greater than 600 g/m2; and coupling a perimeter region of a second sheet of filter media to the rim region to contain the adsorbent beads between the first sheet of filter media and the second sheet of filter media. ### Claim 17 (depends on 16) The method of claim 16, wherein the first sheet of filter media comprises a first layer of filter material and a second layer of scrim material. ### Claim 18 (depends on 16) The method of claim 16, wherein the adsorbent beads have an average size of 0.4 mm to 0.8 mm. ### Claim 19 (depends on 16) The method of claim 16, further comprising increasing the rigidity of the rim region by melting the rim region of the first sheet of filter media and then cooling the rim region of the first sheet of filter media.