LIQUID DISCRIMINATING FUEL VENT VALVE
TECHNICAL FIELD
[0001] The invention relates to a valve assembly with a vent flow bypass for a
fuel tank.
BACKGROUND OF THE INVENTION
[0002] . Fuel tank valve assemblies that control the fluid level within the tank and
provide nozzle shutoff are known. The fuel tanks must include vapor venting ability
for gasses within the tank to maintain balanced pressure as the fuel levels within the
tank change. Additionally, these valve assemblies often provide protection from liquid
escaping during roll over conditions. However it is also desirable to prevent liquid
from escaping due to sloshing of the liquid under normal conditions.
SUMMARY OF THE INVENTION
[0003] A valve assembly for a fuel tank is provided. The valve assembly
includes a housing. A portion of the housing is located at least partially outside of the
fuel tank. The housing also defines a vapor passage. A membrane is supported by the
housing such that the membrane covers the vapor passage. The membrane allows the
passage of vapor through the membrane and prevents the passage of liquid through the
membrane. A flow control feature is supported by the housing to assist in controlling
flow of a vapor through the membrane and the vapor passage. The flow control feature
assists in controlling flow by providing variable flow through the vapor passage. A
splash guard is useful in reducing the amount of, liquid that comes in contact with the
membrane
[0004] The housing includes a vapor recovery housing portion located at least
partially outside of the fuel tank and a fuel tank housing portion located at least partially
within the fuel tank.

[0005] Additionally, a carrier may be secured to the housing. The membrane is
attached to the carrier such that the membrane covers the vapor passage and a carrier
opening is defined by the carrier to allow the passage of vapor and prevent the passage
of liquid.
[0006] The above features and advantages and other features and advantages of
the present invention are readily apparent from the following detailed description of the
best modes for carrying out the invention when taken in connection with the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIGURE 1 is a schematic fragmentary cross-sectional illustration of a
valve assembly mounted to a fuel tank;
[0008] FIGURE 2 is a schematic cross-sectional illustration of a membrane
carrier for the valve assembly of Figure 1;
[0009] FIGURE 3 is a schematic end view illustration of the membrane carrier for
the valve assembly of Figures 1 and 2;
[0010] FIGURE 4 is a schematic cross-sectional illustration of another
embodiment of a valve assembly;
[0011] FIGURE 5 is a schematic cross-sectional illustration of third embodiment
of a valve assembly; and
[0012] FIGURE 6 is a schematic cross-sectional illustration of a fourth
embodiment of a valve assembly.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0013] Referring to the drawings, wherein like reference numbers refer to like
components, Figure 1 shows a valve assembly 10 mounted to a fuel tank 12. The valve
assembly 10 has a housing 14. A first housing portion 16 is located primarily within the
fuel tank 12. A second housing portion 18 is located primarily outside of the fuel tank
12. The housing 14 also defines a vapor passage 20, also referred to as a vent opening,

which is in fluid communication with a vapor outlet 22. The vapor outlet 22 leads to a
vapor recovery canister (not shown) or other destination outside of the tank 12.
[0014] The first housing portion 16 is inserted within a tank hole 24 in the fuel
tank 12. The first housing portion 16 could also be mounted externally with a
passageway that allows communication with the interior of the tank. The first housing
portion 16 includes a flange 26 which is located outside of the fuel tank 12 to prevent the
valve assembly 10 from passing entirely through the tank.hole 24 and into the fuel tank
12. The second housing portion 18 is sometimes referred to as the vapor recovery side of
the housing 14. The second housing portion 18 is secured to the first housing portion 16
at the flange 26. A carrier 28 is located between the first housing portion 16 and the
second housing portion 18. Securing the second housing portion 18 on the first housing
portion 16 retains the carrier 28 to the housing 14.
[0015] Figure 2 illustrates an enlarged cross-sectional view of the carrier 28 and
Figure 3 illustrates a bottom view of the carrier 28 of Figure 1. The carrier 28 is
generally annular in shape having a main body 30. At least one finger 32 protrudes
upwardly from the main body 30. The finger 32 corresponds to indentations 34 (shown
in Figure 1) on the second housing portion 18 when the carrier 28 is assembled with the
housing 14. As discussed above, and illustrated in Figure 1, the main body 30 is
secured between the first housing portion 16 and the second housing portion 18 when
the valve assembly 10 is assembled. The annular shape of the carrier 28 defines a
carrier opening 36 through which vapor within the fuel tank 12 can vent through to the
vapor vent passage 20 (shown in Figure 1). A membrane 38 is secured to the carrier
28 and extends over the entire carrier opening 36. The membrane 38 is of a material
that allows vapor to pass through the membrane 38 but prohibits liquid from passing
through. The membrane may be secured to the carrier 28 by weld, adhesive, heat
sealing, insert molding, on other methods. One skilled in the art would know the
appropriate attachment required for a particular carrier. 28 and membrane 38
arrangement.
[0016] The carrier;28 includes at least one flow control feature 39. In the
embodiment shown the flow control feature 39 is a deflector 40. As the membrane 38

is exposed to liquid, the liquid may slow the flow rate of the vapor through the
membrane. Thus, the deflector 40 deters liquid from retching the membrane 38 to help
maintain the vapor flow rate through the membrane 38 at a predetermined level.
[0017] The deflector 40 extends downwardly and inwardly from the main body
30 of the carrier 28. The deflector 40 defines at least one deflector opening 42 and
may define a plurality of deflector openings. The deflector 40 would assist in directing
liquid away from the membrane 38 and the vapor vent passage 20 while the deflector
opening 42 allows vapor to pass the deflector 40 and exit the fuel tank 12 through the
membrane 38. The size and number of deflector openings 42 may be set to control the
maximum amount of vapor that may pass through at one time. Additionally, the
deflector 40 may include several layers of material with deflector openings 42 at
various locations on each layer of the deflector 40. This would create a tortuous flow
path further assisting in deflecting liquid away from the membrane 38.
[0018] The carrier 28 may also include a plurality of ribs 44 extending upwardly
from the deflector 40. The ribs 44 are arranged radially on the deflector 40 and
provide support for the membrane 38 and assist in stiffening the deflector 40.
Additionally, the flow control feature 39 may include optimizing the size of the carrier
opening 36 to control the maximum flow rate of the vapor that may exit the fuel tank 12
at one time.
[0019] Figure 4 illustrates a second embodiment of a valve assembly 110 having
a carrier 128 for use with a fuel tank 12 (shown in Figure 1). The carrier 128 is
mounted to a housing 114. The carrier 128 includes a main body 130. At least one
finger 132 protrudes upwardly from the carrier 128 to assist in securing the carrier 128
to the housing 114. The main body 130 defines :a carrier opening 136. A membrane
138 is secured to the main body 130 to cover at least the carrier opening 136. The
membrane 138 may be larger in size than the carrier opening 136. The size of the
carrier opening 136 may be determined based upon the maximum desired vapor flow
through the housing 114 tot a vapor vent passage 120. t

[0020] The membrane 138 is illustrated in as a generally flat membrane.
However, the membrane 138 may also be a cylinder or may be pleated to increase the
surface area of the membrane 138. One skilled in the an would know the proper shape
for a membrane 138 for a particular valve assembly 110 arrangement.
[0021] A flow control feature 139 for the valve assembly 110 is a head valve.
The flow control feature 139 includes a disc (or plate) 146. The disc 146 is located
above the carrier 128 within the vapor vent passage 120. The disc 146 defines a disc
opening 148 through which vapor may exit the fuel tank 12 (shown in Figure 1). The
disc opening 148 is smaller in diameter than the carrier opening 136 and is sized to
control the amount of flow at a given pressure inside the tank. When the vapor
pressure within the fuel tank 12 reaches a sufficient level the disc 146 is lifted off the
carrier 138, as shown. The vapor may exit through the disc opening 148 and around
the sides of the disc 146, as illustrated by arrows V. The finger 132 assists in guiding
the'disc 146 in the proper position with respect to the carrier 128. As the vapor
escapes the fuel tank 12 the pressure within the fuel tank 12 decreases and the disc 146
returns to the resting position on the carrier 128. Vapor may still exit the fuel tank
through the disc opening 148 but will not exit around the disc 146 until the pressure
again increases to a level that will raise the disc 146 off the carrier 128.
[0022] The carrier 128 may also include flange protrusions ISO extending
downward from the main body 130. The flange protrusions ISO assist in attaching the
membrane 138 to the carrier 128. The membrane 138 may be attached by weld,
adhesive, heat sealing, insert molding, or other methods. One skilled in the art would
know the appropriate attachment required for a particular carrier 128 and membrane
138 arrangement.
[0023] Figure S illustrates another embodiment of a valve assembly 210. The
valve assembly 210 has a housing 214. The valve assembly 210 has a housing 214 with
features that define at least one passageway 242A and 242B for vapor flow. The
housing 214 interfaces with the fuel tank (not shown).

[0024] A membrane 238 is secured to the housing 214 to cover at least the first .
housing opening 242A and the second housing opening 242B. The size of the first
housing opening 242A and of the second housing opening 242B may be determined
based upon the maximum desired vapor flow through the housing 214 to a vapor
passage 220 also defined by the housing. The membrane 238 is illustrated in as a
generally flat membrane. However, the membrane 238 may also be a cylinder or may
be pleated to increase the surface area of the membrane 238. One skilled in the art
would know the proper shape for a membrane 238 for a particular valve assembly 210
arrangement.
[0025] A flow control feature 239 for the valve assembly 210 is a head valve
which includes a ball 246 located within the second housing opening 242B. The ball
246 is located above the housing 214 partially within the vapor vent passage 220 and
the second bousing opening 242B. The second housing opening 242B may have an
enlarged-or tapered portion 244 for guiding and supporting the ball 246. Vapor may
exit the fuel tank 212 through the first housing opening 242A which includes an orifice
limiting the flow. When the vapor pressure within the fuel tank reaches a sufficient
level the ball 246 is lifted off the housing 214, as shown. The vapor may exit through
the.first housing opening 242A and the second housing opening 242B around the sides
of the ball 246, as illustrated by arrows V. The tapered portion 244 assists in guiding
the ball 246 in the proper position with respect to the housing 214. As the vapor
escapes the fuel tank the pressure within the fuel tank decreases and the ball 246 returns
to the resting position on the housing 214. Vapor may still exit the fuel tank through
the first housing opening 242A but will not exit through the second housing opening
242B until the pressure within the fuel tank again increases to a level that will raise the
ball 246 off the housing 214.
[0026] Figure 6 illustrates another embodiment of a valve assembly 310. The
valve assembly 310 has a housing 314. A first housing portion 316 is located primarily
within the fuel tank 312 and a second housing portion 318 is located primarily outside of
the fuel tank 312. The housing 314 also defines a vapor vent passage 320, also referred

to as a vent opening, which is in fluid communication with a vapor outlet 322. The vapor
outlet 322 leads to a vapor recovery canister (not shown) or other destination outside of
the tank 312.
[0027] The first housing portion 316 is inserted within a tank hole 324 in the fuel
tank 312. The housing 314 includes a flange 326 which is located outside of the fuel tank
312 to prevent the valve assembly 310 from passing entirely through the tank hole 324
and into the fuel tank 312. The second housing portion 318 is sometimes referred to as
the vapor recovery side of the housing 314.
[0028] The housing 314 includes a carrier 328. A membrane 338 is secured to
the carrier 328 by weld, adhesive, heat sealing, insert molding, or other methods. One
skilled in the art would know the appropriate attachment required for a particular
membrane 338.
[0029] The membrane 138 is illustrated in as a generally flat membrane.
However, the membrane 138 may also be a cylinder, may be spirally wound, or may be
pleated to increase the surface area of the membrane 138. One skilled in the art would
know the proper shape for a membrane 138 for a particular valve assembly 110
arrangement.
[0030] The carrier 328 and housing 314 defines a housing opening 348 through
which vapor within the fuel tank 312 can vent through to the vapor vent passage 320.
The membrane 338 is secured to the carrier 328 and extends over the entire housing
opening 348. The membrane 338 is of a material that allows vapor to pass through the
membrane 338 but prohibits liquid from passing through.
[0031] The carrier 328 includes at least one flow control feature 339. In the
embodiment shown, the flow control feature 339 is a restriction in the size of the
housing opening 348 to control the amount of vapor that may exit the fuel lank 312 at
one time.
[0032] Additionally the flow control feature 339 may include a soft shut off
feature on the first housing portion 316. The first housing portion 316, in this instance,
is often referred to as a dip tube. The first housing portion 316 extends downward

within the fuel tank 312. As is known to those skilled in the art the first housing
portion 316 may provide an air pocket to control shut off of a fuel pump when filling
the fuel tank. In the embodiment shown, the first housing portion 316 has a tapered
edge 350 around at least a portion of the first housing portion 316. Additionally, the
first housing portion 316 defines a fuel shut off aperture 352. The tapered edge 350
and the fuel shut off aperture 352 provide for restricted vapor flow as the fuel tank 312
is filled with fluid. Therefore, this will accommodate for sloshing as the fuel tank is
filled, by minimizing the amount of liquid from the sloshing that reaches the membrane
338. The tapered edge 350 and fuel shut off aperture 352 can be used together or
individually to restrict vapor flow into the housing as the liquid level rises until the
tapered edge 350 and the fuel shut off aperture 352 are completely submerged.
[0033] Alternatively to a dip tube, the flow control feature 339 may include a
float located within the first housing portion 316 which may also be used to control fuel
shut off at a fuel pump, as is known in the art.
[0034] While the best modes for carrying out the invention have been described
in detail, those familiar with the art to which this invention relates will recognize
various alternative designs and embodiments for practicing the invention within the
scope of the appended claims.

WE CLAIM
1. A valve assembly (10, 110, 210, 310) fora fuel lank (12, 112,212,312)
comprising:
a housing (14, 114,214, 314) having a housing portion (16, 116, 216, 316)
located at least partially outside of the fuel tank (12, 112,212, 312), wherein the housing
(14,114,214, 314) defines a vapor passage (20, 120,220, 320);
a membrane (38, 138,238,338) supported by the housing (14, 114,214,314)
such that a vapor must flow through the membrane (38, 138,238, 338) to enter the vapor
passage (20, 120, 220, 320);
wherein the membrane (38, 138,238,338) is configured to allow the passage of
the vapor and prevent the passage of a liquid; and
a flow control feature (39, 139,239, 339) supported by the housing (14, 114, 214,
314) to assist in controlling flow of the vapor through the membrane (38, 138, 238, 338)
and the vapor passage (20, 120,220, 320) by one of shielding liquid from the membrane
(38) and providing variable flow through the vapor passage (20, 120, 220, 320).
2. The valve assembly (10, 110,310) of claim 1, further comprising a carrier
(28,128,328) supported by the housing (14, 114, 314), wherein the membrane (38, 138,
338) is secured to the carrier (28, 128, 328).
3. The valve assembly (10) of claim 2, wherein the flow control feature (39)
is a deflector (40) supported by the carrier (28) and extending therefrom, and wherein the
deflector (40) defines a plurality of deflector openings (42).
4. The valve assembly (10) of claim 3, wherein a plurality of annular ribs
(44) extend upwardly from the deflector (40) toward the membrane (38).
5. The valve assembly (10, 110,210,310) of claim 2, wherein the flow
control feature (39, 139, 239, 339) is a head valve.

6. The valve assembly (110) of claim 5, wherein the head valve farther
comprises a disc (146) located in the vapor passage (120) of the housing (114) on a vapor
recovery side of the carrier (128), wherein the disc (146) further defines a disc opening
(148).
7. The valve assembly (110)ofclaim6, wherein carrier (128)ftirther
includes at least one finger (132) extending from the carrier (128) within the vapor
passage (120), wherein the at least one finger (132) guides the disc (146) within the vapor
passage (120).
8. The valve assembly (210) of claim 1, wherein the flow control feature
(239) is a head valve which further comprises:
a first housing passage (242A) defined by the housing (214);
a second housing passage (242B) defined by the housing (214) and generally
parallel to the first housing passage(242A); and
a ball (246) at least partially located within the second housing passage (242B)
and the vapor passage (220).
9. The valve assembly (210) of claim 8, wherein the housing (214) defines a
tapered portion (244) of the second housing passage (242B), and wherein the ball (246) is
supported by the tapered portion (244).
10. The valve assembly (10, 310) of claim 1, wherein the flow control feature
(39, 339) is a portion of the housing (14, 314) extending downward within the fuel tank
(12,312) such that at least a portion (16, 316)of the housing (14, 314) is located on a fuel
tank (12, 312) side of the membrane (38, 38).
11. A valve assembly (10, 110,210, 310) located between a fuel tank (12,
112, 212,312) and a vapor outlet, comprising:

a housing (14,114,214, 314) having a vapor recovery housing portion (16, 116,
216,316) located at least partially outside of the fuel tank (12, 112,212,312) and a fuel
tank(12, 112,212,312) housing portion (16, 116,216,316) located at least partially
within the fuel tank (12, 112, 212,312), and wherein the housing (14, 114,214, 314)
defines a vapor passage (20, 120, 220,320);
a membrane (38, 138, 238, 338) secured to the housing (14, 114, 214, 314) over
the vapor passage (20, 120, 220, 320) and to allow the passage of vapor and prevent the
passage of liquid; and
a flow control feature (39, 139, 239,339) supported by the housing (14, 114, 214,
314) to assist in controlling flow of a vapor through the membrane (38, 138, 238, 338)
and the vapor passage (20, 120, 220, 320).
12. The valve assembly (10) of claim 11, wherein the flow control feature (39)
is a deflector (40) located on a fuel tank (12) side of the membrane (38).
13. The valve assembly (10) of claim 12, wherein a plurality of annular ribs
(44) extend from the deflector (40) toward the membrane (38).
i
14. The valve assembly (110, 210) of claim 11, wherein the flow control
feature (39) is a head valve located on a vapor recovery side of the membrane (138,238)
that provides variable vapor flow through the vapor passage (120, 220).

A valve assembly (10, 110, 210, 310) for a fuel tank (12, 112, 212, 312)
includes a housing (14, 114, 214, 314). A membrane (38, 138, 238, 338)
supported by the housing (14, 114, 214, 314) such that the membrane (38,
138, 238, 338) covers a vapor passage (20) defined by the housing (14, 114,
214, 314). The membrane (38, 138, 238, 338) allows the passage of vapor
through the membrane (38, 138, 238, 338) and prevents the passage of liquid
through the membrane (38, 138, 238, 338). A flow control feature (39, 139,
239, 339) is supported by the housing (14, 114, 214, 314) to assist in
controlling flow of a vapor through the membrane (38, 138, 238, 338) and
the vapor passage (20, 120, 220, 320). The flow control feature (39, 139,
239, 339) assists in controlling flow by one of shielding liquid from the
membrane (38, 138, 238, 338) and providing variable flow through the
vapor passage (20,120, 220, 320).