`
`U.S. Patent
`
`Mar.25,2003
`
`Sheet 1 of 5
`
`US 6,537,355 B2
`
`10
`
`FIG.
`
`FIG. 2
`
`12
`
`18
`
`FIG. 3
`
`15
`I
`I
`I
`I
`
`17
`
`20
`
`28
`
`24
`
`
`
`U.S. Patent
`
`Mar.25,2003
`
`Sheet 2 of 5
`
`US 6,537,355 B2
`
`18
`
`30
`
`FIG. 4
`
`FIG. 5
`
`34
`
`50
`
`26
`
`60
`
`
`
`U.S. Patent
`
`Mar.25,2003
`
`Sheet 3 of 5
`
`US 6,537,355 B2
`
`FIG. 6
`
`62
`
`26
`
`FIG. 7
`
`
`
`U.S. Patent
`
`Mar.25,2003
`
`Sheet 4 of 5
`
`US 6,537,355 B2
`
`38
`
`66
`
`38
`
`FIG. 8
`
`68
`
`/
`
`/
`
`FIG. 9
`
`FIG. 10
`
`
`
`U.S. Patent
`
`Mar.25,2003
`
`Sheet 5 of 5
`
`US 6,537,355 B2
`
`
`
`72
`
`FIG. 11
`FIG. 11
`
`
`
`US 6,537,355 B2
`
`1
`EVAPORATIVE EMISSION TREATMENT
`DEVICE
`
`TECHNICAL FIELD
`This disclosure relates to evaporative emission treatment
`systems, and, more particularly, to an evaporative emission
`treatment device.
`
`2
`FIG. 8 is a partial cross-sectional view of an embodiment
`of a half shell comprising a plurality of ribs disposed within
`the inlet portion of the half shell.
`FIG. 9 illustrates an embodiment of an attachment mem-
`5 ber disposed at either or both the inlet portion and outlet
`portion of an embodiment of a shell.
`FIG. 10 illustrates an embodiment of an attachment
`member disposed at either or both the inlet portion and outlet
`portion of an embodiment of a shell.
`FIG. 11 illustrates the embodiment of the evaporative
`emission treatment device of FIG. 4 further comprising two
`different mounting members.
`
`10
`
`BACKGROUND
`Evaporative emission treatment systems typically com(cid:173)
`prise a fuel tank, internal combustion engine, intake mani(cid:173)
`fold assembly, carbon canister, and various lines and vents
`to treat evaporative emissions. The evaporative emissions
`typically contain evaporated fuel, or hydrocarbon vapors, 15
`that "bleed" from the aforementioned components during
`and after operating a motor vehicle. The carbon canisters
`trap the majority of hydrocarbon vapor that escapes from
`these components. However, carbon canisters do not com(cid:173)
`pletely prevent hydrocarbon vapor from being released into 20
`the atmosphere. As a result, conventional carbon canisters
`and evaporative emission treatment systems do not meet
`stringent emission regulations.
`Consequently, there exists a need for an evaporative
`emission treatment device that prevents hydrocarbon vapor 25
`leakage into the atmosphere.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENT
`The evaporative emission treatment device comprises a
`monolith concentrically disposed within a shell, and having
`one or more sealing agents concentrically disposed about the
`monolith and in between the monolith and housing. The
`shell comprises a first half shell having an inlet portion at
`one end and a connection element disposed at the opposing
`end, and a second half shell having an outlet portion at one
`end and a connection element disposed at the opposing end.
`The shell can also include structural features to prevent fluid
`leakage, enhance fluid flow, enable attachment to other
`evaporative emission system components, enable mounting
`to a vehicle, and internally seal the monolith and sealing
`agents.
`The evaporative emission treatment device further com-
`prises concentrically disposing one or more sealing agents
`about a monolith. The monolith/sealing agent subassembly
`can be concentrically disposed within a first end of a first
`half shell. The first half shell further comprises a second end
`0
`~~~~:~ti~nc~1::~:~
`containing the monolith/sealing agent subassembly can be
`secured together to form an evaporative emissions treatment
`device assembly. One or more mounting members can be
`40 affixed thereto to form an evaporative emissions treatment
`device assembly to facilitate the desired attachment.
`The evaporative emission treatment device can comprise
`a carbon canister, hydrocarbon-scrubbing device, and the
`like, and preferably a hydrocarbon-scrubbing device. The
`45 hydrocarbon-scrubbing device can include a monolith, also
`referred to as a brick, substrate, or support. The monolith
`preferably comprises an activated carbon element such as
`that described in U.S. Pat. No. 5,914,294 to Park et al. which
`is incorporated by referenced herein.
`The monolith can be supported within the housing using
`one or more sealing agents concentrically disposed about it,
`wherein the sealing agents are preferably flexible. The
`sealing agents can comprise a variety of materials such as
`elastomeric materials, polymeric materials, foam, plastic
`55 ( e.g., thermoplastic materials, and the like), composite
`materials, and the like. For example, the sealing agent
`preferably disposed near the inlet and outlet of the shell
`comprises sponge rubber sealing material such as nitrile
`sponge; fluorocarbon rubber sponge referred to as
`60 "VITON®" (commercially available from Lauren Manufac(cid:173)
`turing Company, New Philadelphia, Ohio); epichlorohydrin
`rubber sponge; and combinations comprising at least one of
`the foregoing sponge rubber sealing materials, and the like,
`with VITON® preferred.
`The sealing agents can further comprise one or more
`sleeve like portions comprising a sponge rubber sealing
`material, and preferably comprises two sleeves of sponge
`
`if :~:~i:1 ~~:; s~:~. ~e ~~:~~:f f :~el;
`
`SUMMARY
`The drawbacks and disadvantages of the prior art are
`overcome by the evaporative emission treatment device, and
`its method of manufacture, described herein. The evapora(cid:173)
`tive emission treatment device comprises a monolith con(cid:173)
`centrically disposed in a shell. In addition, a sealing agent is
`concentrically disposed about the monolith, and in between
`the shell and monolith. The method for manufacturing an
`evaporative emission treatment device comprises disposing
`a sealing agent about a monolith to form a monolith/sealing
`agent subassembly. The monolith/sealing agent subassembly
`is concentrically disposed in a first half shell. The first half
`shell is connected and secured to a second half shell.
`
`30
`
`35
`
`50
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`Referring now to the Figures, which are meant to be
`exemplary, and not limiting, and wherein like elements are
`numbered alike in the figures.
`FIG. 1 is an isometric, partial cut-away view of an
`embodiment of the evaporative emission treatment device.
`FIG. 2 is an isometric, partial cut-away view of an
`embodiment of the evaporative emission treatment device
`including an alternative embodiment of a sealing agent.
`FIG. 3 illustrates an additional embodiment of the evapo(cid:173)
`rative emission treatment device of FIG. 1 assembled using
`a spin-weld connection.
`FIG. 4 illustrates yet another embodiment of the evapo(cid:173)
`rative emission treatment device of FIG. 1 assembled using
`a twist-lock connection.
`FIG. 5 illustrates another embodiment of the evaporative
`emission treatment device of FIG. 1 assembled using a
`snap-fit design.
`FIG. 6 is a partial cross-sectional view of the first and
`second half shells of the evaporative emission treatment
`device of FIG. 4 illustrating a sealing agent disposed within
`the first and second half shells.
`FIG. 7 is a partial cross-sectional view of an embodiment 65
`of a shell comprising a first half shell, a second half shell,
`and a pair of diffusers disposed at either end of the shell.
`
`
`
`US 6,537,355 B2
`
`10
`
`3
`rubber sealing material concentrically disposed about the
`monolith at either, or between, the inlet portion and outlet
`portion of the monolith as illustrated in FIG. 1. This sealing
`agent forces the fluids to flow into the monolith, preventing
`them from flowing around the monolith. The sealing agent 5
`can be extruded, for example, to the desired length for the
`particular application and cut to form the sleeve or plurality
`of sleeves. The sealing agent eliminates the need for con(cid:173)
`ventional adhesives that can ultimately emit hydrocarbons
`into the atmosphere.
`In an alternative embodiment, the sealing agent can
`comprise one or more molded elastomeric seals comprising
`a conventional moldable elastomer material alone or in
`conjunction with the above sealing agents. The molded
`elastomeric seals can preferably comprise an annular seal
`having an annular shoulder portion that can be concentri(cid:173)
`cally disposed about and engage either the inlet or outlet of
`the monolith, and preferably disposed about and engaging
`both the inlet and the outlet of the monolith to form a
`monolith/sealing agent subassembly.
`The monolith/sealing agent subassembly can be concen(cid:173)
`trically disposed within a first half shell, which can be
`connected to a second half shell to form the evaporative
`emission treatment device assembly (See FIGS. 1-4). The
`shells can comprise a non-ferrous or ferrous material
`capable of operating in an evaporative emissions environ(cid:173)
`ment having the following characteristics: (1) capable of
`operating at temperatures up to about 125° C.; and (2)
`capable of withstanding exposure to hydrocarbons, carbon
`dioxide, and/or water. Possible non-ferrous materials can
`include plastics, composite materials, and combinations
`comprising at least foregoing non-ferrous materials, and the
`like. Possible ferrous materials can include carbon steels,
`alloys, and combinations comprising at least one of the
`foregoing ferrous materials.
`The first half shell can comprise an inlet portion at one
`end and a connection element disposed at the opposing end.
`In contrast, the second half shell can comprise an outlet
`portion at one end and a connection element disposed at the
`opposing end. Possible connection elements for either the
`first half shell and/or second half shell can include a spin(cid:173)
`weld, twist-lock, snap-fit, and combinations comprising at
`least one of the foregoing connection elements (See FIGS.
`3-6). A spin weld connection can include any type of weld
`that can preferably sealingly secure the first half shell to the
`second half shell (See FIG. 3). Possible types of welds can
`include a TIG weld (Tungsten Inert Gas), MIG weld, spot
`weld, seam weld, and combinations comprising at least one
`of the foregoing welds. When employing the spin-weld
`connection, the second half shell can preferably comprise an
`end cap having an inlet portion or outlet portion, and a
`connection element that preferably comprises a spin-weld
`connection, which compliments a first half shell for connec(cid:173)
`tion thereto.
`Each connection comprises a first connection element
`( e.g., twist-lock, snap-fit, and the like) disposed on the first
`half shell, and a second connection element (e.g., twist-lock,
`snap-fit, and the like) disposed on the second half shell,
`wherein the first and second connection elements are mate(cid:173)
`able (See FIG. 4). A sealing agent can be disposed within the
`shell to provide support to the monolith and seal the housing
`to prevent leakage. Preferably, this seal, which can comprise
`any of the above sealing agents, comprises polymeric
`materials, elastomeric materials, foam, plastic, composite
`materials, and combinations comprising at least one of the
`foregoing sealing agents, with elastomeric materials
`preferred, and an elastomeric a-ring especially preferred. An
`
`4
`a-ring can be concentrically disposed within either the first
`half shell or second half shell, or within both half shells at
`their connection point, and between either or both half shells
`and the monolith (See FIG. 6). For example, a first twist(cid:173)
`lock connection element and the second twist-lock connec(cid:173)
`tion element can preferably engage each other, and be
`secured together by a twisting motion in either a clockwise
`or counter-clockwise direction. The twisting motion can
`preferably sealingly secure the first half shell and second
`half shell together, and retain the a-ring in place, e.g.,
`concentrically disposed between the monolith/sealing agent
`subassembly and either or both half shells.
`Both the first half shell and second half shell can further
`comprise additional structural features designed to further
`support the monolith, enhance fluid flow, enable attachment
`15 to other evaporative emission system components, and
`enable mounting to a vehicle. In one embodiment of the
`shell design, to further support the monolith, a plurality of
`ribs, dimples, protrusions, or the like, can be disposed within
`the interior of either or both the first half shell and second
`20 half shell (See FIG. 8) The ribs can preferably be disposed
`at or near the inlet portion of the first half shell and/or,
`optionally, the outlet portion of the second half shell. As the
`monolith, or monolith/sealing agent subassembly is concen(cid:173)
`trically disposed with the half shell, the monolith can contact
`25 the plurality of ribs and rest upon the ribs, thus receiving
`support.
`In another embodiment of the shell design, a diffuser
`element can be concentrically disposed about the inlet
`portion of the first half shell and/or the outlet portion of the
`30 second half shell (See FIG. 7). The diffuser element distrib(cid:173)
`utes the flow of vapors across the face of the monolith. The
`diffuser provides lower flow restriction and improves flow
`distribution across the monolith as the flow translates
`through the device. The diffuser element can be sized and
`35 dimensioned according to the particular application, with its
`size, geometry, and desired flow distribution properties
`ultimately dependant upon the customer's requirements and
`particular application.
`In yet another embodiment of the shell design, both the
`40 first half shell and second half shell can further comprise an
`attachment element to attach the device to an evaporative
`emissions system component, or other system component in
`the vehicle. Possible attachment elements can include a
`quick-connect (FIG. 9), fir-tree (FIG. 10), other conven-
`45 tional attachment elements, and methods including, but not
`limited to, swaging, screwing, beaded tube, clamping,
`crimping, bracketing, and like, and combinations compris(cid:173)
`ing at least one of the foregoing attachment elements and/or
`methods, and the like. The attachment elements, such as the
`50 quick-connect and fir-tree designs, can be employed at the
`inlet and/or outlet portions of each half shell to simplify
`system integration, such as integration with an evaporative
`emission treatment system, and the like, within a vehicle.
`In yet another additional embodiment of the shell design,
`55 one or more mounting members can be attached to the shell
`to facilitate mounting the evaporative emission treatment
`device in any orientation to an evaporative emission treat(cid:173)
`ment system, and the like, within a vehicle. Possible mount(cid:173)
`ing members can include mounting tabs (See FIG. 11),
`60 dovetail mounting tabs (See FIG. 11), "belly band guides"
`(See FIG. 4), and combinations comprising at least one of
`the foregoing mounting members that can mounted by
`snapping, slidingly engaging, screwing, and combinations
`comprising at least one of the foregoing methods, in any
`65 orientation to a vehicle's system.
`The additional structural features designed to further
`support the monolith, enhance fluid flow, enable attachment
`
`
`
`US 6,537,355 B2
`
`5
`to other evaporative emission system components, and
`enable mounting to a vehicle, can be incorporated alone or
`in combination with each other. For example, a shell design
`comprising snap-fit connection element can also further
`comprise a diffuser disposed at the inlet portion of the
`assembly, and optionally a diffuser also disposed at the
`outlet portion of the assembly. That same embodiment can
`also further comprise a plurality of ribs disposed within
`either the first half shell or second half shell, or both to
`provide additional support to the monolith. Likewise, the 10
`inlet portion can further comprise quick-connect attachment
`element while the outlet portion comprises a fir-tree attach(cid:173)
`ment element or a quick-connect attachment element.
`Ultimately, the assembly's design will depend upon the
`particular application and customer packaging requirements, 15
`and can vary accordingly depending upon those particular
`requirements.
`To illustrate the methods for manufacturing the evaporate
`emission treatment device, and treating hydrocarbon vapors
`from an evaporative emission system, reference will now be 20
`made to FIGS. 1-11. FIG. 1 illustrates an embodiment of a
`hydrocarbon scrubber comprising a monolith 10 disposed in
`a conventional shell 12. A plurality of sealing agents 14 are
`concentrically disposed around the monolith, and in between
`the monolith 10 and shell 12. The sealing agents 14 ensure
`that fuel vapors will not bypass the monolith and flow
`between the shell and monolith. This ensures that the fuel
`vapors are adsorbed and not emitted into the atmosphere.
`The sealing agent 14 also cushions and protects the monolith
`10 from breaking during operation of the vehicle, such as
`when experiencing vibrations. Likewise, as illustrated in
`FIG. 2, the annular seals 15 are concentrically disposed
`about both the inlet and outlet of the monolith 10 such that
`a shoulder 17 of each seal 15 engages the inlet and outlet of
`the monolith 10. The annular seals 15 also cushion and 35
`protect the monolith 10 as do the sealing agents 14.
`The monolith/sealing agent subassembly can be concen(cid:173)
`trically disposed within an embodiment of a shell. Referring
`now to FIGS. 3 and 8, the monolith/sealing agent subas(cid:173)
`sembly can be concentrically disposed within a first half
`shell 16 having an inlet portion 18 and a connection element
`20. In addition, a plurality of ribs 38 can be disposed within
`the interior of either, or both, the first half shell 16 and
`second half shell, and/or at the outlet of the first shell half 16,
`i.e., disposed adjacent to endcap 24. The ribs can preferably
`be disposed at or near the inlet portion of the first half shell,
`or, optionally, the outlet portion of the second half shell, and
`can provide additional support to the monolith during opera(cid:173)
`tion of the vehicle. The first half shell 16 can be secured
`using a spin-weld connection 22 to an end cap 24 having an
`outlet portion 26 and a connection element 28.
`In another embodiment, and referring now to FIGS. 4 and
`6, the monolith/sealing agent subassembly can be concen(cid:173)
`trically disposed within a first half shell 30 having an inlet
`portion 18 and a connection element 32. The first half shell 55
`30 can be secured using a twist-lock connection 34, and an
`a-ring 62 concentrically disposed within the first half shell
`30 and between the shell 30 and the monolith (not shown),
`to a second half shell 36 having an outlet portion 26 and a
`connection element 40.
`In yet another embodiment, and referring now to FIGS.
`5-6, the monolith/sealing agent subassembly can be con(cid:173)
`centrically disposed within a first half shell 42 having an
`inlet portion 18 and a connection element 46. The first half
`shell 42 can be secured using a snap-fit connection 48, and 65
`an a-ring 62 concentrically disposed within the first half
`shell 42 and between the shell 42 and the monolith (not
`
`6
`shown), to a second half shell 50 having an outlet portion 26
`and a connection element 54. The assembly can be mounted
`to a vehicle using a mounting member 56 comprising a first
`mounting element 58 of the first half shell 42 and a second
`5 mounting element 60 of the second half shell 50.
`Each embodiment illustrated in FIGS. 3-5 can include a
`diffuser element 64 concentrically disposed about the inlet
`portion 18 of the assembly. Optionally, the diffuser element
`64 can also be concentrically disposed about the outlet
`portion 26 of the assembly as well. In addition, each
`embodiment can be attached to other vehicle components
`using an attachment element, such as a quick-connect attach(cid:173)
`ment 66 (FIG. 10), a fir-tree attachment 68 (See FIG. 9), and
`the like, affixed to either or both the inlet portion 18 and
`outlet portion 26. Basically, the assembly can be employed
`in the engine, the air intake, and/or coupled with a base
`canister for evaporative emissions from the fuel tank, and
`the like.
`Each embodiment can also be mounted to a vehicle using
`a mounting member such as mounting member 56 illustrated
`in FIG. 4. Other possible mounting members include a
`mounting tab element 70 and a dovetail mounting element
`72, which are both illustrated in FIG. 11. These mounting
`members can also be incorporated into the assembly designs
`25 illustrated in FIGS. 3 and 5, as well as other assembly
`designs incorporating additional structural features.
`Ultimately, the assembly's design will depend upon the
`particular application and customer packaging requirements,
`and can vary accordingly depending upon those particular
`30 requirements.
`The evaporative emission treatment device, illustrated in
`FIGS. 1-11, possess several advantages over conventional
`evaporative emission treatment devices. The use of the
`flexible seal protects the carbon monolith from vibrations
`and other motions imparted by the vehicle to the assembly
`during operation. FIGS. 1-11 illustrate assembly designs
`that can protect the carbon monolith, as well as meet specific
`customer packaging requirements.
`The hydrocarbon scrubber performance is based upon
`structural features that prevent fluid leakage, enhance fluid
`flow, enable attachment to other evaporative emission sys(cid:173)
`tem components, enable mounting to a vehicle, and inter(cid:173)
`nally seal the monolith and sealing agents. These design
`45 features provide the necessary protection, performance
`enhancements, and functionality necessary to ensure optimal
`hydrocarbon scrubber performance.
`While preferred embodiments have been shown and
`described, various modifications and substitutions may be
`50 made thereto without departing from the spirit and scope of
`the invention. Accordingly, it is to be understood that the
`present invention has been described by way of illustration
`and not limitation.
`What is claimed is:
`1. An evaporative emission treatment device, comprising:
`a monolith suitable for adsorbing hydrocarbon evapora-
`tive emissions;
`a shell concentrically disposed about said monolith; and
`a first sealing agent concentrically disposed about said
`monolith, between said shell and said monolith,
`wherein said first sealing agent has a shoulder engaging
`a face of an end of the monolith.
`2. The evaporative emission treatment device of claim 1,
`wherein said substrate further comprises a carbon monolith.
`3. The evaporative emission treatment device of claim 1,
`wherein said shell further comprises a first shell portion and
`a second shell portion.
`
`40
`
`60
`
`
`
`US 6,537,355 B2
`
`7
`4. The evaporative emission treatment device of claim 3,
`wherein at least one of said first shell portion and said
`second shell portion further comprises a plurality of ribs,
`dimples or protrusions disposed.
`5. The evaporative emission treatment device of claim 3, 5
`wherein said second shell portion comprises an end cap.
`6. The evaporative emission treatment device of claim 5,
`wherein said first shell portion and said second shell portion
`each further comprise a connection selected from the group
`consisting of a snap-fit connection, a twist-lock connection, 10
`and a spin-weld connection.
`7. The evaporative emission treatment device of claim 5,
`wherein at least one of said first shell portion and said
`second shell portion further comprise an attachment element
`selected from the group consisting of a quick-connect 15
`attachment and a fir-tree attachment.
`8. The evaporative emission treatment device of claim 1,
`wherein said shell further comprises a mounting member
`selected from the group consisting of a belly band guide,
`dovetail mounting element, a mounting tab, and combina(cid:173)
`tions comprising at least one of the foregoing mounting
`members.
`9. The evaporative emission treatment device of claim 1,
`wherein said first sealing agent further comprises a sponge
`rubber sealing material selected from the group consisting of 25
`nitrile sponge, fluorocarbon rubber sponge, epichlorohydrin
`rubber sponge, and combinations comprising at least one of
`the foregoing sponge rubber sealing materials.
`10. The evaporative emission treatment device of claim 1,
`wherein said first sealing agent further comprises a plurality 30
`of sleeves concentrically disposed about said monolith.
`11. The evaporative emission treatment device of claim
`10, wherein said first sealing agent sleeves are disposed at
`locations selected from the group consisting of an inlet
`portion of said monolith, an outlet portion of said monolith, 35
`between said inlet portion and said outlet portion of said
`monolith, and combinations comprising at least two of the
`foregoing locations.
`12. The evaporate emission treatment device of claim 1,
`further comprising a second sealing agent concentrically 40
`disposed about said monolith, between said shell and said
`monolith, and adjacent to a connection joint between a first
`shell portion and a second shell portion.
`13. The evaporate emission treatment device of claim 12,
`wherein said second sealing agent selected from the group 45
`consisting of polymeric materials, elastomeric materials,
`foam, plastic, composite materials, and combinations com(cid:173)
`prising at least one of the foregoing second sealing agents.
`14. The evaporative emission treatment device of claim
`12, wherein said second sealing agent further comprises an 50
`a-ring.
`15. An evaporative emission treatment device, compris(cid:173)
`ing:
`a monolith suitable for adsorbing hydrocarbon evapora(cid:173)
`tive emissions;
`a shell concentrically disposed about said monolith, said
`shell having a first shell portion mated to a second shell
`portion; and
`a plurality of sealing agents concentrically disposed about
`said monolith, between said shell and said monolith,
`wherein at least a first sealing agent is disposed adja-
`
`8
`cent to a connection joint formed between said first
`shell portion and said second shell portion, and an
`annular seal having a shoulder engaging a face of an
`end of the monolith.
`16. The evaporate emission treatment device of claim 15,
`wherein said first sealing agent is selected from the group
`consisting of polymeric materials, elastomeric materials,
`foam, plastic, composite materials, and combinations com(cid:173)
`prising at least one of the foregoing second sealing agents.
`17. The evaporative emission treatment device of claim
`15, wherein said first sealing agent is an a-ring.
`18. The evaporative emission treatment device of claim
`15, further comprising a second sealing agent disposed near
`an inlet portion of said monolith and a third sealing agent
`disposed near an outlet portion of said monolith.
`19. The evaporative emission treatment device of claim
`18, wherein said second sealing agent and said third sealing
`agent individually further comprise a sponge rubber sealing
`material selected from the group consisting of nitrile sponge,
`20 fluorocarbon rubber sponge, epichlorohydrin rubber sponge,
`and combinations comprising at least one of the foregoing
`sponge rubber sealing materials.
`20. A method for manufacturing an evaporative emission
`treatment device, comprising:
`disposing a sealing agent comprising an annular seal
`about a monolith to form a monolith/sealing agent
`subassembly, wherein said monolith is suitable for
`adsorbing hydrocarbon evaporative emissions;
`said annular seal having a shoulder engaging a face of an
`end of the monolith;
`disposing said monolith/sealing agent subassembly in a
`first shell portion;
`connecting said first shell portion to a second shell
`portion; and
`securing said first shell portion and said second shell
`portion.
`21. The method of claim 20, further comprising disposing
`a plurality of sleeves of said sealing agent about said
`monolith.
`22. The method of claim 21, wherein said plurality of
`sleeves are disposed at locations selected from the group
`consisting of an inlet portion of said monolith, an outlet
`portion of said monolith, between said inlet portion and said
`outlet portion of said monolith, and combinations compris(cid:173)
`ing at least two of the foregoing locations.
`23. The method of claim 20, further comprising contact(cid:173)
`ing said monolith/sealing agent subassembly with a plurality
`of ribs, dimples or protrusions disposed within said first shell
`portion.
`24. The method of claim 20, wherein said connecting
`further comprises connecting said first shell portion and said
`second shell portion using a connection element selected
`from the group consisting of a snap-fit connection, a twist-
`55 lock connection, a spin-weld connection, and combinations
`comprising at least one of the foregoing connection ele(cid:173)
`ments.
`25. The method of claim 20, further comprising disposing
`a second sealing agent within said first shell portion, wherein
`said second sealing agent further comprises an a-ring.
`
`60
`
`* * * * *
`
`