METHOD OF PACKAGING A MEMBRANE FOR USE IN A
VENTING VALVE
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Patent Application Serial No. 12/582,197,
filed October 20, 2009, which is incorporated herein in its entirety by reference.
TECHNICAL FIELD
[0002] The present invention relates to valves including liquid discriminating and vapor
permeable membranes.
BACKGROUND
[0003] Fuel level responsive venting valves are conventionally used in automobile fuel
tanks. Venting valves may be located in the fuel tank to remain open when the fuel is below a
certain level and to close when the fuel reaches the valve. Two common applications of these
valves are "rollover" valves, which respond to abnormal fuel levels or unusual vehicle angles by
closing a vapor outlet from the tank, and fuel shutoff or "fill control" valves which are positioned
to close when the fuel tank reaches the "full" level during refueling.
[0004] To protect the emissions system against fuel spills from the vapor vent line in a fuel
tank in the event of a vehicle rollover, venting valves are configured to close the vapor vent
when the vehicle is tilted beyond a safe threshold amount from the normal upright position.
These venting valves may employ a float that closes the valve when the liquid level of the fuel
rises above a predetermined level to prevent liquid fuel from sloshing out of the vapor vent either
during normal operation or in the event of rollover.
[0005] Venting valves vent fuel vapor from a vehicle fuel tank to the atmosphere or to an
evaporative emissions system, which may include a carbon canister. Such valves typically vent
the interior of the fuel tank to the evaporative emissions system when the fuel in the tank is
below the level of the valve and close when the fuel level surges (e.g., in a rollover situation or
during fuel sloshing from driving maneuvers). In some cases, rollover valves may also be
submerged at the end of a fuel fill. Closing the valve in response to surging liquid fuel levels
prevents the overflow of liquid fuel into the evaporative emissions system. If the valve is used as
a fill-control vent valve, the valve may generally close in response to a full fuel level, creating a
pressure head within the fuel tank and filler pipe to operate an automatic shutoff apparatus built
into the fuel fill nozzle.
[0006] Although mechanical floats (which may include floats, springs, other mechanical
means, or combinations thereof) may be used to partially and/or completely close fuel vent
valves, they involve moving parts and can be relatively complex. Alternative methods to prevent
liquid fuel from entering the vapor recovery system and/or to partially or completely seal the fuel
vent in case of vehicle rollover may involve using a membrane in place of a mechanical means,
such as a float. The membrane may be capable of venting vapor (e.g., fuel vapor) from a
container (e.g., fuel tank) to a vapor recovery system. The membrane may further be configured
to prevent liquid from passing through and accordingly can also serve the rollover valve
function. In a conventional membrane design, the membrane may be substantially disk shaped
and may extend over a substantial portion of a cover for the vent valve.
[0007] In order to meet the functional requirements of the venting valve (e.g., based on the
flow needs of the venting valve), the membrane may require a significant amount of surface area.
In order to increase the surface area of a substantially disk-shaped membrane, there is an
undesirable and significant increase in size and packaging (i.e., the disk-shaped membrane must
be increased in diameter and circumference in order to increase the surface area). Accordingly,
it may be desirable to utilize a method of packaging a membrane that has an increased membrane
surface area to meet functional requirements but maintains substantially the same dimensions
and physical space requirements as conventional valves.
SUMMARY
[0008] In an embodiment, a venting valve comprises a cover including a flow path in fluid
communication with an evaporative emissions system; and a liquid discriminating and vapor
permeable membrane connected to the cover. At least a portion of the outer surface of the
membrane may comprise a plurality of alternating curved crests and valleys.
[0009] In another embodiment, a venting valve comprises a cover including a flow path in
fluid communication with an evaporative .emissions system; and a liquid discriminating and
vapor permeable membrane connected to the cover. The membrane may comprise a first and
second layer defining a gap therebetween. At least a portion of the membrane may be spirally
wound.
[00010] In another embodiment, a venting valve comprises a cover including a flow path in
fluid communication with an evaporative emissions system and a liquid discriminating and vapor
permeable membrane connected to the cover. At least a portion of the membrane may be curved,
and at least one protrusion may be configured to support and shape the membrane.
BRIEF DESCRIPTION OF THE DRAWINGS
[00011] Embodiments of the invention will now be described, by way of example, with
reference to the accompanying drawings, wherein:
[00012] FIG. 1 is a schematic view of a vehicle fuel system employing a venting valve in
accordance with an embodiment of the invention.
[00013] FIG. 2A is a partial perspective view of a venting valve of FIG. 1 including a
membrane in accordance with an embodiment of the invention.
[00014] FIG. 2B is a cross-sectional view of a venting valve of FIG. 1 including a
membrane in accordance with en embodiment of the invention.
[00015] FIGS. 2C and 2D are sectional views cut along plane 2C—2C on FIG. 2B.
[00.016] FIG. 2E is a cross-sectiona! view of a venting valve of FIG. 1 including a housing
in accordance with an embodiment of the invention.
[00017] FIG. 2F is perspective view of the housing of FIG. 2E in accordance with an
embodiment of the invention.
[00018] FIGS. 3A-3B are top views of a membrane for a venting valve of FIG. 1 in
accordance with another embodiment of the invention.
[00019] FIG. 3C is a side view of the membrane shown in FIGS. 3A-3B.
[00020] FIG. 4 is a side view of a membrane for a venting valve of FIG. 1 in accordance
with another embodiment of the invention.
[00021] FIGS. 5A-5B are perspective views of a membrane for a venting valve of FIG. 1 in
accordance with another embodiment of the invention.
[00022] FIG. 6 is a perspective view of a membrane for a venting valve of FIG. 1 in
accordance with another embodiment of the invention.
[00023] FIG. 7 is a perspective view of a venting valve of FIG. 1 including a membrane in
accordance with another embodiment of the invention.
[00024] FIG. 8 is another perspective view of the venting valve of FIG. 7.
[00025] FIG. 9 is a partial perspective view of the membrane of the venting valve of FIGS.
7-8 in accordance with an embodiment of the invention.
[00026] FIG. 10 is a partial perspective view of a membrane for a venting valve of FIG. 1 in
accordance with another embodiment of the invention, including additional supporting structure
for the membrane.
[00027] FIGS. 11 A-11C are perspective views of a membrane for a venting valve of FIG. 1
in accordance with other embodiments of the invention.
DETAILED DESCRIPTION
[00028] Reference will now be made in detail to embodiments of the present invention,
examples of which are described herein and illustrated in the accompanying drawings. While the
invention will be described in conjunction with embodiments, it will be understood that they are
not intended to limit the invention to these embodiments. On the contrary, the invention is
intended to cover alternatives, modifications and equivalents, which may be included within the
spirit and scope of the invention as embodied by the appended claims.
[00029] FIG. 1 illustrates a schematic view of a vehicle fuel system. The vehicle fuel
system may include a dip tube 11, a fuel tank 12, a recirculation line 13, a fill cup 15, and a
refueling nozzle 17. The fuel tank 12 may contain liquid fuel. The vehicle fuel system may also
include a filler pipe 14 for introducing fuel into the fuel tank 12. The vehicle fuel system may
further include an evaporative emissions system 16 (e.g., carbon canister) to which fuel vapor is
vented from the tank 12 through valve 10 via a vent line 18. Venting valve 10 may be
configured so that vapor may rise through the venting valve 10. The venting valve 10 may be
generally mounted in a vent hole in a fuel tank 12 of a vehicle fuel system. Although various
elements of a vehicle fuel system are generally described and illustrated, the venting valve 10 in
accordance with the present invention may be utilized in any number of vehicle fuel systems
which omit certain elements that are described or illustrated and/or include additional elements
that are not described or illustrated herein. The venting valve 10 may be configured for use
between a vehicle fuel tank vent and the vapor recovery system 16.
[00030] Referring now to FIG. 2A, the venting valve 10 may comprise a cover 20 (e.g.,
cap) and a liquid discriminating and vapor permeable membrane 22. The cover 20 may be
molded, for example, from a fuel resistant plastic and may be mounted in a wall of the fuel tank
12. The cover 20 may be mounted to the fuel tank 12 using any known and/or conventional
method and/or manner, including for example, welding (e.g., ultrasonic welding), bonding (e.g.,
with adhesive), a camlock design with an elastomeric seal, and/or fasteners (e.g., screws, bolts,
rivets, brads, etc.). The cover 20 may include a flange 24 configured to support the venting
valve 10 in a fuel tank 12 of a vehicle fuel system. For example, the flange 24 may be generally
circular in shape in accordance with an embodiment of the invention. The cover 20 may further
include a flow path 26 (e.g., a port, a line, or any other path). Flow path 26 may be configured
forfluidly connecting a venting orifice (to which vapor may rise through the venting valve 10) to
the evaporative emissions system 16 (e.g., carbon canister). Accordingly, flow path 26 of cover
20 may be in fluid communication with the evaporative emissions system 16 and may allow for
the transfer of vapor from fuel tank 12 to the evaporative emissions system 16.
[00031] In accordance with an embodiment of the invention, the membrane 22 of venting
valve 10 may be connected to cover 20. For example and without limitation, the venting valve
10 may include a means 28 for connecting the membrane 22 to the cover 20. Means 28 may also
be configured to ensure that the flow path of fluid from the fuel tank 12 is through membrane 22
(i.e., membrane 22 cannot be bypassed). Referring now to FIG. 2B, in accordance with an
embodiment of the invention, the membrane 22 of venting valve 10 may be directly connected to
cover 20. For example, in an embodiment, the means 28 for connecting the membrane 22 to the
cover 20 may include one or more projections 25, 27 defining a channel into which the
membrane 22 may be disposed. The membrane 22 may be connected to the cover 20 using
adhesive located in the channel defined by the projections 25,27, insert molding, or otherwise
embedding the membrane. The membrane 22 may further utilize an end cap 36 as described
further herein in accordance with an embodiment of the invention. In accordance with another
embodiment, means 28 may comprise a post 29 that is substantially centered relative to cover 20
of venting valve 10 in an embodiment of the invention, as generally illustrated in FIG. 7, for
example. The post 29 may comprise plastic in an embodiment of the invention. The post 29
may be connected to the cover 20 using any known and/or conventional method and/or manner,
including, for example and without limitation, an insert molding process, welding (e.g.,
ultrasonic welding), heat sealing, bonding (e.g., with adhesives), a combination thereof, or any
number of other processes. The post 29 may also be connected to the membrane 22. The post
29 may be connected to the membrane 22 using any known and/or conventional method and/or
manner, including for example and without limitation, an insert molding process, welding (e.g.,
ultrasonic welding), heat sealing, bonding (e.g., with adhesives), a combination thereof, or any
number of other processes. Although means 28 are described in detail as projections 25, 27
and/or post 29 in accordance with various embodiments of the invention, means 28 may
comprise any element and/or member and/or process that is configured to connect the membrane
22 to cover 20 and to ensure that the flow path for fluid from the fuel tank 12 is through the
membrane 22 (i.e., that fluid cannot bypass membrane 22).
[00032] The membrane 22 may be configured to allow passage of air and/or fuel vapor
while blocking passage of liquid fuel. The membrane 22 may be a liquid discriminating
membrane. In accordance with an embodiment of the invention, the membrane 22 may be
configured so that it does not change the hydrocarbon concentration of the air and/or fuel vapor
that passes through the membrane 22. Fuel vapor may enter the venting valve 10 at the fuel tank
side of the venting valve. To increase the surface area of the membrane 22 while maintaining
substantially the same dimensions and physical space requirements as conventional membrane
packaging for venting valves (e.g., substantially disk shaped membranes), the membrane 22 may
comprise a number of various packages or methods for packaging as described herein.
[00033] Referring to FIGS. 2A, 2C, and 2D, in accordance with embodiments of the
invention, the membrane 22 may comprise a rippled, corrugated, and/or wavy membrane
package. In particular, at least a portion of the outer surface of the membrane 22 may comprise a
plurality of alternating curved crests 30 and valleys 32 that define ripples, corrugations, and/or
waves on the outer surface of the membrane 22. In other words, at least a portion of the outer
surface of the membrane 22 has a substantially sinusoidal profile. The membrane 22 may be
formed into a substantially columnar shape, having a longitudinal axis 34, in accordance with an
embodiment of the invention and as generally illustrated in FIG. 2A. The longitudinal axis 34 of
the substantially columnar membrane 22 may extend perpendicularly from cover 20. The
ripples, corrugations, and/or waves defined by the curved crests 30 and valleys 32 may aiso
extend along the longitudinal axis 34 of the substantially columnar membrane 22. The
membrane 22 may form a hollow member in accordance with an embodiment of the invention.
Although the membrane 22 is described as being a substantially columnar hollow member, the
membrane 22 may comprise any number of other shapes in other embodiments.
[00034] For example, referring now to FIGS. 3 A-3B which show top views of a membrane
22 for use with a venting valve 10 in accordance with another embodiment of the invention, the
membrane 22 may be not curved into a substantially cylindrical hollow member. Instead, the
membrane 22 may be relatively flat. As generally illustrated in FIG. 3A, the membrane 22 may
be substantially circular in shape and/or disk-shaped. As generally illustrated in FIG. 3B, the
membrane 22 may be substantially rectangular in shape. Although these two shapes are
described and illustrated, the membrane 22 may comprise any number of shapes, including, for
example, irregular shapes, in other embodiments of the invention. As best seen in the side view
illustrated in FIG. 3C, the membrane 22 continues to comprise a plurality of alternating curved
crests 30 and valleys 32 that define ripples, corrugations, and/or waves on the outer surface of
the membrane 22. Accordingly, the membrane 22 is not actually flat, but has a substantially
sinusoidal profile and continues to have an increased surface area because of the ripples,
corrugations, and/or waves formed on the outer surface. The membrane 22 may be connected to
venting valve 10 using means 28 (e.g., projections and/or a post configured to connect membrane
28 to cover 20 and/or any known and/or conventional method and/or manner, including for
example, an insert molding process, welding (e.g., ultrasonic welding), heat sealing, bonding
(e.g., with adhesives), a combination thereof, or any number of other processes). In accordance
with an embodiment of the invention, the means 28 may comprise a direct connection between
membrane 22 and cover 20 in accordance with an embodiment of the invention such that no
separate connecting element (such as projections or a post) is necessary.
[00035] For another example of a rippled, corrugated, and/or wavy membrane package that
does not include a substantially columnar hollow member, reference is now made to FIG. 4. The
membrane 22 may be formed into a substantially wedge-shaped and/or V-shaped package. A
first end 33 of the membrane 22 may be wider than a second opposing end 35 of the membrane
22. However, at least a portion of the outer surface of the membrane 22 may continue to
comprise a plurality of alternating curved crests 30 and valleys 32 that define ripples,
corrugations, and/or waves on the outer surface of the membrane 22. Accordingly, at least a
portion of the outer surface of the membrane 22 may have a substantially sinusoidal profile. The
ripples, corrugations, and/or waves may extend perpendicularly to the longitudinal axis 34 of the
substantially wedge-shaped and/or V-shaped membrane 22. The membrane 22 may be
connected to venting valve 10 using means 28 described herein and/or any known and/or
conventional method and/or manner, including for example, an insert molding process, welding
(e.g., ultrasonic welding), heat sealing, bonding (e.g., with adhesives), a combination thereof, or
any number of other processes. ). In accordance with an embodiment of the invention, the
means 28 may comprise a direct connection between membrane 22 and cover 20 in accordance
with an embodiment of the invention such that no separate connecting element (such as
projections or a post) is necessary. One or more substantially triangular shaped pieces (not
shown) may be used to seal the edges of the membrane 22 in order to maintain a closed inner
vapor space separate from the fuel tank vapor space.
[00036] In accordance with another embodiment of the invention, the membrane 22 may
comprise a ribbon-like membrane package. Referring now to FIGS. 2D and 5A-5B, at least a
portion of the outer surface of the membrane 22 may continue to comprise a plurality of
alternating curved crests 30 and valleys 32. However, as opposed to creating relatively shallow
ripples, corrugations, and/or waves on the outer surface of the membrane, at least one of the
plurality of curved crests 30 may have a profile that is at least substantially hemispherical. Also,
in some embodiments, at least one of the plurality of curved valleys 32 may have a profile that is
at least substantially hemispherical. In some embodiments, each of the plurality of curved crests
30 and/or valleys 32 may have a profile that is at least substantially hemispherical. In
accordance with an embodiment of the invention, at least one of the plurality of curved crests 30
and/or at least one of the plurality of curved valleys 32 may have a profile that extends about
equal to or greater than about 180° of a circle. In some embodiments, each of the plurality of
curved crests 30 and/or valleys 32 may have a profile that extends about equal to or greater than
about 180° of a circle. In accordance with an embodiment of the invention, at least one of the
plurality of curved crests 30 may have a profile that extends at least about 270° of a circle. In
some embodiments, at least one of the plurality of curved valleys may have a profile that extends
at least about 270° of a circle. In some embodiments, each of the plurality of curved crests 30
and/or valleys 32 may have a profile that extends about equal to or greater than about 270° of a
circle. Accordingly, the ripples, corrugations, and/or waves on the outer surface may be more
pronounced than those generally illustrated in FIGS. 3A-3C. In other words, at least a portion of
the outer surface of the membrane 22 may have a substantially corrugated profile.
[00037] The membrane 22 may also be formed in to a substantially columnar shape, having
a longitudinal axis 34, in accordance with an embodiment of the invention and as generally
illustrated in FIG. 5B. The longitudinal axis 34 of the substantially columnar membrane may
extend perpendicularly from cover 20. The membrane 22 may be connected to venting valve 10
using means 28 (e.g., projections and/or a post and/or any known and/or conventional method
and/or manner, including for example, an insert molding process, welding (e.g., ultrasonic
welding), heat sealing, bonding (e.g., with adhesives), a combination thereof, and/or a direct
connection between membrane 22 and cover 20, or any number of other processes and/or
embodiments). The pronounced ripples and/or waves may extend along the longitudinal axis 34
of the substantially columnar membrane 22. The membrane 22 may form a hollow member in
accordance with an embodiment of the invention. Although the membrane 22 is described as
being a substantially cylindrical columnar member, the membrane 22 may comprise any number
of other shapes in other embodiments.
[00038] For example, as generally illustrated in FIG. 6, the membrane 22 may be formed
into a substantially wedge-shaped and/or V-shaped package. A first end 33 of the membrane 22
may be wider than a second opposing end 35 of the membrane 22. However, at least a portion of
the outer surface of the membrane 22 continues to comprise a plurality of alternating curved
crests 30 and valleys 32 that define a rippled profile as generally shown in FIG. 5A on the outer
surface of the membrane 22. Accordingly, in other words, at least a portion of the outer surface
of the membrane 22 has a substantially corrugated profile. The ripples may extend
perpendicularly to the longitudinal axis 34 of the substantially wedge-shaped and/or V-shaped
membrane 22. The membrane 22 may be connected to venting valve 10 using means 28 (e.g.,
projections and/or a post and/or any known and/or conventional method and/or manner,
including for example, an insert molding process, welding (e.g., ultrasonic welding), heat
sealing, bonding (e.g., with adhesives), a combination thereof, and/or a direct connection
between membrane 22 and cover 20, or any number of other processes and/or embodiments). As
generally illustrated in FIG. 6, means 28 may comprise plate 37 that is generally shown at the
first wider end 33 of the membrane 22. Plate 37 may be configured for connection to membrane
22 using an insert molding process, welding (e.g., ultrasonic welding), heat sealing, bonding
(e.g., with adhesives), or a combination thereof. Plate 37 may be considered an end cap in
accordance with some embodiments of the invention. One or more substantially triangular
shaped pieces (not shown) may be used to seal the edges of the membrane 22 in order to
maintain a closed inner vapor space separated from the fuel tank vapor space.
[00039] Referring back to FIG. 2B, in accordance with various embodiments of the
invention, the venting valve 10 may further comprise a first end cap 36. First end cap 36 may be
connected to a first end 38 of the hollow member formed by membrane 22. First end cap 36 may
be configured for sealing the first end 38 of the hollow member and/or retaining the shape of the
hollow member. First end cap 36 may be connected to membrane 22 using any known and/or
conventional method and/or manner in the art, including for example, adhesives. First end cap
36 may include a plurality of projections 40, 42 defining a channel into which the membrane 22
may be disposed. FIG. 2B generally shows first end cap 36 connected to membrane 22 using
adhesive. Venting valve 10 may further comprise a second end cap (not shown) in accordance
with some embodiments of the invention. The second end cap may be connected to a second end
of the hollow member formed by membrane 22 that opposes the first end 38. The second end
cap may be used in addition to and/or as part of means 28 for connecting the membrane 22 to the
cover 20. The second end cap, if any, may also be connected to membrane 22 using any known
and/or conventional method an/or manner in the art, including for example, adhesives. The
second end cap may include a hole for vapor flow. The hole may in fluid communication with
the flow path 26 of cover 20. Vapor may flow from fuel tank 12, through membrane 22, through
the hole of the second end cap and/or through cover 20, through the flow path 26, and to
evaporative emissions system 16. In this way, the membrane 22 provides two distinct vapor
spaces (i.e., the first vapor space is inside the fuel tank 12 and the second vapor space is outside
the fuel tank 12). Although first end caps 36 and second end caps are described in detail, end
caps may not necessarily be used in connection with the embodiments of the invention. For
example and without limitation, first end cap 36 may not be used in connection with wedge-
shaped and/or V-shaped membranes generally illustrated in FIGS. 4 and 6. For another example,
holes for vapor flow may be placed directly in the membrane itself.
[00040] Referring now to FIG. 2A, in accordance with an embodiment of the invention, the
venting valve 10 may further comprise a structural support member 44 extending through the
hollow member defined by the membrane 22. The structural support member 44 may be
configured to be disposed in the hollow member. In one embodiment, the support member 44
may comprise a solid support. In other embodiments, the support member 44 may comprise a
mesh structure support. The support member 44 may be generally cylindrical or columnar in an
embodiment. Although the support member 44 is described as being generally cylindrical or
columnar, the support member 44 may, however, comprise any number of other shapes in other
embodiments. The support member 44 may extend along the longitudinal axis 34 of membrane
22. The support member 44 may be configured for press-fit insertion through the hollow
member defined by the membrane 22. The support member 44 may function as a gap spacer in
some embodiments of the invention, and may be configured to maintain the gap between
opposing sides of the membrane 22. For example, a support member may be configured to
support the wedge-shaped and/or V-shaped membrane 22 generally shown in FIGS. 4 and 6, and
to maintain a gap between opposing sides of the membrane 22. The support member 44 may
also comprise means 28 for connecting the membrane 22 to the cover 20 in accordance with an
embodiment of the invention.
[00041] In some embodiments, the venting valve 10 may further comprise a housing 46 that
at least partially surrounds (e.g., is exterior to) the membrane 22 as generally illustrated in FIGS.
2E-2F. The housing 46 may be cylindrical or generally cylindrical in shape in accordance with
an embodiment of the invention. The housing 46 may be configured to prevent liquid fuel from
splashing onto the membrane 22, which could potentially affect the functionality of the
membrane 22. The housing 46 may also be configured to prevent external damage (e.g.,
crushing) of the membrane 22. Although the housing 46 is generally illustrated as surrounding
the membrane 22, the housing 46 does not have to surround and/or be exterior to the membrane
22. In accordance with various embodiments of the invention, the housing 46 may be interior to
the membrane 22. Such an embodiment with an interior housing 46 may still be configured to
prevent external damage (e.g., crushing) of the membrane 22, but would not necessarily be
configured for splash protection. In accordance with some embodiments of the invention, the
housing 46 may be perforated (as generally illustrated in FIG. 2F), may include slits, may
comprise mesh, and/or any other similar variation configured to permit venting of the housing
46. Although a housing 46 is described in connection with venting valve 10, the housing 46 is
not necessary and may not be utilized in accordance with some embodiments of the invention.
[00042] In accordance with another embodiment of the invention, the venting valve 10 may
include a spiral-wound membrane package as generally illustrated in FIGS. 7-8. Elements of the
venting valve 10 (including for example, but not limited to, cover 20, flange 24, flow path 26,
means 28, housing 46) may be identical and/or substantially similar to the elements described in
connection with other embodiments of the invention, except the membrane may comprise a
spiral-wound membrane 48. Spiral-wound membrane 48 may be liquid discriminating and vapor
permeable. Spiral-wound membrane 48 may be configured to allow for the passage of air and/or
fuel vapor, while blocking the passage of liquid fuel. In accordance with an embodiment of the
invention, the spiral-wound membrane 48 may be configured so that it does not change the
hydrocarbon concentration of the air and/or fuel vapor that passes through the spiral-wound
membrane 48. The spiral wound membrane 48 may be connected to venting valve 10 using
means 28 described herein (e.g., post 29 and/or any known and/or conventional method and/or
manner, including for example, an insert molding process, welding (e.g., ultrasonic welding),
heat sealing, bonding (e.g., with adhesives), a combination thereof, or any number of other
processes). In accordance with an embodiment of the invention, the means 28 may comprise a
direct connection between membrane 22 and cover 20 in accordance with an embodiment of the
invention such that no separate connecting element (such as projections or a post) is necessary.
[00043] The spiral-wound membrane 48 may comprise a substantially flat membrane that is
first folded (e.g., folded in half) to make an envelope. The edges of the membrane 48 may be
sealed in order to create a first vapor space inside the envelope and a second vapor space outside
the envelope (e.g., the fuel tank vapor space). Accordingly, the membrane 48 may comprise a
first and second layer 50, 52 (e.g., the first half of the substantially flat membrane is the first
layer 50, and the second half of the substantially membrane is the second layer 52). The
membrane 48 comprising the folded envelope may then be spirally wound (e.g., rolled up into a
spiral-wound membrane 48).
[00044] The first and second layers 50, 52 of the membrane 48 may define a gap 54
therebetween. In one embodiment, the membrane 48 may be generally self-supporting to retain
gap 54 between layers 50, 52. In other embodiments, the membrane 48 may use a device 56 that
is configured to maintain the gap 54 between the first and second layer 50, 52 of the membrane
48. For example, the device 56 may comprise a runner.
[00045] Referring now to FIG. 9, device 56 is generally illustrated as a plurality of runners.
The runners 56 may extend along the longitudinal axis 34 of the spiral-wound membrane 48 in
an embodiment of the invention. In other embodiments, the runners 56 may extend
perpendicularly to and/or at any other angle relative to the longitudinal axis 34 of the spiral-
wound membrane 48. The runners 56 may extend the entire length of the first layer 50 and/or
second layer 52 of the spiral-wound membrane 48 or may extend only along a portion of the first
layer 50 and/or second layer 52 of the spiral-wound membrane 48. The runners 56 may
generally comprise a flexible material and may comprise a plastic in an embodiment of the
invention. The runners 56 may have a substantially triangular cross-section in an embodiment of
the invention, although the runners may comprise any number of shapes in accordance with other
embodiments of the invention. Each of the runners 56 may be attached to the membrane 48
through a process, such as insert molding, ultrasonic welding, etc. or be inserted as a separate
piece between the layers 50, 52 of the membrane 48. The device 56 is not limited to runners as
illustrated and may include any other device configured to create and/or maintain the gap 54
between the first and second layers 50, 52 of the spiral-wound membrane 48. For example and
without limitation, in other embodiments, the device 56 may comprise a mesh, screen, net, braid,
etc. The device 56 comprising a mesh, screen, net, braid, etc. may also comprise a flexible
material and/or may also comprise plastic in accordance with embodiments of the invention.
[00046] The membrane 48 may also include a hole (not shown) for vapor flow. The hole
may be in fluid communication with the flow path 26 of the cover 20. Vapor may flow from fuel
tank 12, through layer 50 or layer 52 of membrane 48, through the gap 54 defined between layers
50 and 52 of membrane 48, through the hole of the membrane 48, through the flow path 26, and
to the vapor recovery system 16. In this way, the membrane 48 provides two distinct vapor
spaces (i.e., the first vapor space is inside the fuel tank 12, and the second vapor space is outside
the fuel tank 12). The membrane envelope makes up part of the second vapor space outside the
fuel tank 12. '
[00047] In accordance with another embodiment of the invention, the venting valve 10 may
include a dome membrane package as generally illustrated in FIG. 10. Elements of the venting
valve 10 (including for example, but not limited to, cover 20, flange 24, flow path 26, post 28,
housing 46) may be identical and/or substantially similar to the elements described in connection
with other embodiments of the invention, except the membrane may comprise a dome membrane
58. Dome membrane 58 may also be liquid discriminating and vapor permeable. Dome
membrane 58 may also be configured to allow for the passage of air and/or fuel vapor, while
blocking the passage of liquid fuel. Membrane 58 may not generally be configured to filter the
fuel vapor (i.e., substantially change (e.g., lower and/or increase) the hydrocarbon concentration
of the fuel vapor) in an embodiment of the invention. At least a portion of dome membrane 58
may be generally curved and/or hemispherical in an embodiment of the invention. The dome
membrane 58 may further include a circumferentially extending flange 60 that may be used to
connect the dome membrane 58 to the venting valve 10.
[00048] In order to provide support and/or form the dome membrane 58 of the membrane
package, a corresponding protrusion 62 may be provided. Protrusion 62 may comprise a rib
member in accordance with an embodiment of the invention. For example and without
limitation, protrusion 62 may comprise at least one curved rib 64 that is configured to support
and/or shape the membrane 58. The dome membrane 58 may be configured to be provided
and/or placed on the protrusion 62 (e.g., on a rib 64 of the protrusion 62 in an embodiment of the
invention). Protrusion 62 may further comprise a circumferentially extending flange 66 in
accordance with an embodiment of the invention. Flange 66 may include at least one lug and/or
tooth 68. Lugs and/or teeth 68 may be used to hold the membrane 58 in place. In particular,
lugs and/or teeth 68 may be used to hold flange 60 of membrane 58 in place against flange 66 of
protrusion 62. A corresponding ring 70 that matches up with flanges 60 and 66 may also be used
to retain membrane 58 in place. The dome membrane 58 may be connected to venting valve 10
so that the curved and/or hemispherical portion (i.e., the convex side) faces cover 20 of venting
valve 10 in an embodiment. The dome membrane 58 may also be connected to venting valve 10
so that the curved and/or hemispherical portion (i.e., the convex side) faces away from cover 20
of venting valve 10 (i.e., toward fuel tank 12). The dome membrane 58 may be connected to
venting valve 10 using post 28 described herein and/or any known and/or conventional method
and/or manner, including for example, an insert molding process, welding (e.g., ultrasonic
welding), heat sealing, bonding (e.g., with adhesives), a combination thereof, or any number of
other processes. The dome membrane 58 may also be directly connected to cover 20 in
accordance with an embodiment of the invention.
[00049] A first side of the dome membrane 58 (e.g., the convex side or concave side) may
be in fluid communication with the vapor space inside the fuel tank 12. A second, opposing side
of the dome membrane (e.g., the concave side or convex side, respectively) may be in fluid
communication with the vapor space including flow path 26 of cover 20. Vapor may flow from
fuel tank 12, through membrane 58, through the flow path 26, and to evaporative emissions
system 16. In this way, the dome membrane 58 provides two distinct vapor spaces (i.e., the first
vapor space is inside the fuel tank 12 and the second vapor space is outside the fuel tank 12).
[00050] Although these various embodiments have been described in detail, there may be
numerous other variations for methods of packaging a membrane for use in a venting valve that
may increase the surface area in order to improve the functionality of the membrane, while not
requiring significant increases in physical space requirements for the venting valve. For example
and without limitation, in other embodiments, the membrane may comprise a sock-type
membrane package as generally illustrated in FIGS. 11A-1 IB. In the sock-type membrane
package, the membrane 72 may comprise a hollow member formed by one or a plurality of
panels. The membrane 72 may comprise four side panels as generally illustrated in FIG. 11 A,
and accordingly may comprise a rectangular shape. However, in other embodiments, the
membrane 72 may comprise fewer or more panels (e.g., three side panels forming a triangular
shape as generally illustrated in FIG. 1 IB). Although four side panels and three side panels are
mentioned and generally illustrated, the membrane 72 may comprise any number and types of
panels in various embodiments. For example, as generally illustrated in FIG. 11C, the membrane
72 may comprise a single panel formed into a V-shaped and/or wedge-shaped membrane
package. A first end 16 of the membrane 72 may be wider than a second opposing end 74 of the
membrane 72. One or more substantially triangular shaped pieces (not shown) may be used to
seal the edges of the V-shaped and/or wedge shaped membrane package generally illustrated in
FIG. 11C to maintain a closed inner vapor space separate from the fuel tank vapor space.
[00051] The membrane 72 may be sealed at a first end 74. As shown in FIGS. 11A-1 IB, a
bottom panel may seal the multiple side panels of the hollow member through the use of seams.
As shown in FIG. 11C, the single panel of the V-shaped itself creates a sealed first end 74. The
membrane 72 may include a plate 37 and/or an end cap (not shown) at a second end 76, the
second end 76 opposing the first end 74. The end cap may be configured for retaining the shape
of the hollow member in some embodiments of the invention. The end cap may be connected to
the membrane 72 using any known and/or conventional method and/or manner in the art,
including for example, adhesives. The end cap may include a hole for vapor flow. The hole in
the end cap may be in fluid communication with the flow path 26 of cover 20. Vapor may thus
flow from fuel tank 12, through membrane 72, through the hole of the end cap, through flow path
26, and to evaporative emissions system 26. In this way, the membrane 72 provides two distinct
vapor spaces (i.e., the first vapor space is inside the fuel tank 12 and the second vapor space is
outside the fuel tank 12). Although an end cap is described in detail, an end cap may not
necessarily be used in connection with the embodiments of the invention. For example, the
membrane 72 itself and/or plate 37 may include a hole for vapor flow, without the use of an end
cap. The membrane 72 may be connected to venting valve 10 using means 28 described herein
and/or any known and/or conventional method and/or manner, including for example, an insert
molding process, welding (e.g., ultrasonic welding), heat sealing, bonding (e.g., with adhesives),
a combination thereof, or any number of other processes.
[00052] The foregoing descriptions of specific embodiments of the present invention have
been presented for purposes of illustration and description. They are not intended to be
exhaustive or to limit the invention to the precise forms disclosed, and various modifications and
variations are possible in light of the above teaching. The embodiments were chosen and
described in order to explain the principles of the invention and its practical application, to
thereby enable others skilled in the art to utilize the invention and various embodiments with
various modifications as are suited to the particular use contemplated. The invention has been
described in great detail in the foregoing specification, and it is believed that various alterations
and modifications of the invention will become apparent to those skilled in the art from a reading
and understanding of the specification. It is intended that all such alterations and modifications
are included in the invention, insofar as they come within the scope of the appended claims. It is
intended that the scope of the invention be defined by the claims appended hereto and their
equivalents.
We Claim:
1. A venting valve (10), comprising:
a cover (20) including a flow path (26) in fluid communication with an evaporative
emissions system (16); and
a liquid discriminating and vapor permeable membrane (22) connected to the cover (20),
wherein at least a portion of the outer surface of the membrane (22) comprises a plurality of
alternating curved crests (30) and valleys (32).
2. The venting valve (10) of claim 1, further comprising a means (28) for connecting the
membrane (22) to the cover (20).
3. The venting valve (10) of claim 2, wherein the means (28) comprises insert molding,
ultrasonic welding, heat sealing, adhesives, or a combination thereof.
4. The venting valve (10) of claim 1, wherein the evaporative emissions system (16)
comprises a carbon canister.
5. The venting valve (10) of claim 1, wherein the membrane (22) is configured to prevent
liquid from passing through the membrane (22).
6. The venting valve (10) of claim 1, wherein the cover (20) includes a flange (24)
configured to support the venting valve (10) in a fuel tank (12) of a vehicle fuel system.
7. The venting valve (10) of claim 1, wherein the venting valve (10) is configured for use
between a vehicle fuel tank vent and the evaporative emissions system (16) in a vehicle fuel tank
(12) containing liquid fuel.
8. The venting valve (10) of claim 1, wherein the membrane (22) extends perpendicularly
from the cover (20).
9. The venting valve (10) of claim 1, wherein the membrane (22) is substantially columnar
in shape.
10. The venting valve (10) of claim 1, wherein the membrane (22) forms a hollow member.
11. The venting valve (10) of claim 10, further comprising a first end cap (36) connected to a
first end (38) of the hollow member, the first end cap (36) configured for sealing the first end
(38) of the hollow member and retaining the shape of the hollow member.
12. The venting valve (10) of claim 11, further comprising a second end cap connected to a
second end of the hollow member, wherein the second end cap includes a hole for vapor flow,
wherein the hole is in fluid communication with the flow path (26) of the cover (20).
13. The venting valve (10) of claim 10, further comprising a structural support member (44)
extending through the hollow member.
14. The venting valve (10) of claim 1, further comprising a housing (46) that at least partially
surrounds the membrane (22).
15. The venting valve (10) of claim 1, wherein at least a portion of the outer surface of the
membrane (22) has a substantially sinusoidal profile.
16. The venting valve (10) of claim 1, wherein at least a portion of the outer surface of the
membrane (22) has a substantially corrugated profile.
17. The venting valve (10) of claim 1, wherein at least one of the plurality of curved crests
(30) or at least one of the plurality of curved valleys (32) or a combination thereof has a profile
that is at least substantially hemispherical.
18. The venting valve (10) of claim 1, wherein at least one of the plurality of curved crests
(30) or at least one of the plurality of curved valleys (32) or a combination thereof has a profile
that extends greater than 180° of a circle.
19. The venting valve (10) of claim 1, wherein at least one of the plurality of curved crests
(30) or at least one of the plurality of curved valleys (32) or a combination thereof has a profile
that extends at least 270° of a circle.
20. A venting valve (10), comprising:
a cover (20) including a flow path (26) in fluid communication with an evaporative
emissions system (16); and
a liquid discriminating and vapor permeable membrane (48) connected to the cover (20),
wherein the membrane (48) comprises a first and second layer (50, 52) defining a gap (54)
therebetween, and wherein at least a portion of the membrane (48) is spirally wound.
21. The venting valve (10) of claim 20, wherein the membrane (48) includes a hole for vapor
flow, wherein the hole is in fluid communication with the port (26) of the cover (20).
22. The venting valve (10) of claim 20, further comprising a device (56) that is configured to
maintain the gap (54) between the first and second layer (50, 52) of the membrane (48).
23. A venting valve (10)* comprising:
a cover (20) including a flow path (26) in fluid communication with an evaporative
emissions system (16);
a liquid discriminating and vapor permeable membrane (58) connected to the cover (20),
wherein at least a portion of the membrane (58) is curved; and
at least one protrusion (62) configured to support and shape the membrane (58).

ABSTRACT

A venting valve (10) comprises a cover (20) including a flow path (26) in fluid
communication with an evaporative emissions system (16) and a liquid discriminating and vapor
permeable membrane (22) connected to the cover (20). At least a portion of the outer surface of
the membrane (22) comprises a plurality of alternating curved crests (30) and valleys (32). In other embodiments, the membrane (48) comprises a first and second layer (50, 52) defining a gap (54) therebetween, wherein at least a portion of the membrane (48) is spirally wound. In other embodiments, the venting valve (10) includes at least one protrusion (62) configured to support and shape the membrane (58), wherein at least a portion of the membrane (58) is curved.