DUAL DIFFUSION PATH FILTER WITH DIFFERENTIAL FLOW RESISTANCES

• US 20110109989A1
• Filed: 11/12/2009
• Published: 05/12/2011
• Est. Priority Date: 11/12/2009
• Status: Active Grant

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Inventors: Ma, Yue, Turner, Robert Dean, Olivero, David Andrew, Haddock, Quinn Jay
• Granted Patent: US 9,865,309 B2
• Time in Patent Office: Days
• US Class Current: 360/97.02
• CPC Class Codes: G11B 33/146 constructional details of filters
• CPC Class Codes: G11B 33/1486 Control/regulation of the pressure, e.g. the pressure inside the housing of a drive

Abstract

An apparatus and associated method for enclosing an environment-sensitive component. An enclosure separates an interior environment inside the enclosure from an external environment outside the enclosure. The enclosure has an environmental control system that captures a contaminant from the internal environment to a filter via a first diffusion path, and captures the contaminant from the external environment to the same filter via a different second diffusion path, the diffusion paths providing substantially different flow resistances to fluids carrying the contaminants to the filter via the respective diffusion paths.

Claims

1. An apparatus comprising:

an enclosure sized to contain an environment-sensitive component, the enclosure separating an internal environment inside the enclosure from an external environment outside the enclosure; and

a filter fluidly coupled to the enclosure, the filter comprising;

a housing containing a filter media;

a first diffusion path fluidly connecting the filter media to the internal environment; and

a second diffusion path fluidly connecting the filter media to the external environment, wherein a flow resistance of the second diffusion path is lower than a flow resistance of the first diffusion path.

2. The apparatus of claim 1 wherein the filter is operably supported inside the enclosure.

3. The apparatus of claim 1 wherein at least one of the diffusion paths is placed in fluid communication entirely with the external environment outside the enclosure by a seal that operably sealingly engages a surface of the housing.

4. The apparatus of claim 3 wherein the enclosure comprises a base and a cover removably connected to the base, wherein the seal is compressingly engaged against the surface of the housing as a direct result of the operable attachment of the cover to the base.

5. The apparatus of claim 4 wherein the housing is operably supported inside the enclosure without any removable fasteners except for removable fasteners that are used to operably attach the cover to the base.

6. The apparatus of claim 3 wherein the seal is compressingly engaged against the surface of the housing as a direct result of the operable attachment of a fastener that mounts the housing to the enclosure.

7. The apparatus of claim 1 wherein at least one of the diffusion paths is formed as a unitary portion of the housing.

8. The apparatus of claim 7 wherein both of the diffusion paths are formed as unitary portions of the housing.

9. The apparatus of claim 1 wherein the flow resistance of each diffusion path is defined in terms of a ratio of a cross-sectional area of the diffusion path to a length of the diffusion path.

10. The apparatus of claim 1 wherein the filter media operably adsorbs contaminants from at least one of the internal and external environments in a first environmental state of the apparatus.

11. The apparatus of claim 10 wherein the filter media operably releases the previously adsorbed contaminants simultaneously to the internal and external environments in a second environmental state of the apparatus.

12. The apparatus of claim 11 wherein an amount of the contaminants in the internal environment is associated with a relative humidity state of the internal environment.

13. An enclosure for containing an environment-sensitive component and that separates an interior environment inside the enclosure from an external environment outside the enclosure, the enclosure comprising an environmental control system that captures a contaminant from the internal environment to a filter via a first diffusion path and captures the contaminant from the external environment to the same filter via a different second diffusion path, the diffusion paths providing substantially different flow resistances to fluids carrying the contaminants to the filter via the respective diffusion paths.

14. The enclosure of claim 13 wherein the filter comprises a housing operably holding a filter media and controlling fluid communication between the filter media and the interior environment via the first diffusion path, and controlling fluid communication between the filter media and the external environment via the second diffusion path, wherein a flow resistance of the second diffusion path is lower than a flow resistance of the first diffusion path.

15. The enclosure of claim 14 wherein the flow resistance of each diffusion path is defined in terms of a ratio of a cross-sectional area of the diffusion path to a length of the diffusion path.

16. The enclosure of claim 13 wherein the filter operably adsorbs the contaminant.

17. The enclosure of claim 16 wherein the environmental control system, in response to an environmental state change, operably releases previously adsorbed contaminants simultaneously to both the internal and external environments.

18. The enclosure of claim 17 wherein the environmental control system, in response to the environmental state change, operably releases previously adsorbed contaminants simultaneously to the internal environment and to the external environment subject to first and second flow resistances, respectively, wherein the second flow resistance is less than the first flow resistance.

19. The enclosure of claim 18 wherein the contaminant is associated with a relative humidity of the internal environment.

20. A method for operating an apparatus having an environment-sensitive component, the method comprising:

placing the environment-sensitive component in an enclosure that separates an internal environment inside the enclosure from an external environment outside the enclosure, the enclosure fluidly coupled to a filter housing containing a filter media such that the filter media is fluidly connected to the internal environment via a first diffusion path and is fluidly connected to the external environment via a second diffusion path, wherein a flow resistance of the second diffusion path is lower than a flow resistance of the first diffusion path.

subjecting the apparatus to first environmental state conditions causing the filter media to capture contaminants from at least one of the internal and external environments; and

subsequently subjecting the apparatus to second environmental state conditions causing the filter media to release the previously captured contaminants from the filter media via simultaneous fluid flows through both diffusion paths.