U.S. patent application number 13/075832 was filed with the patent office on 2012-03-29 for vapor emission control fuel cap.
This patent application is currently assigned to UNIFIED MARINE, INC.. Invention is credited to Arden Haynes, David B. Nirenberg.
Application Number | 20120074147 13/075832 |
Document ID | / |
Family ID | 45869616 |
Filed Date | 2012-03-29 |
United States Patent
Application |
20120074147 |
Kind Code |
A1 |
Nirenberg; David B. ; et
al. |
March 29, 2012 |
Vapor Emission Control Fuel Cap
Abstract
A fuel tank assembly with a fuel cap sub-assembly that includes
active (that is, automatic) pressure equalization hardware and a
passive (that is, manually operated) vent. The fuel cap assembly
further includes radially oriented ratchet teeth. The fuel cap
assembly further includes single piece fuel cap tether that is
anchored in the interior space of the fuel tank.
Inventors: |
Nirenberg; David B.; (Bonita
Springs, FL) ; Haynes; Arden; (Knoxville,
TN) |
Assignee: |
UNIFIED MARINE, INC.
Newport
TN
|
Family ID: |
45869616 |
Appl. No.: |
13/075832 |
Filed: |
March 30, 2011 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
61318842 |
Mar 30, 2010 |
|
|
|
Current U.S.
Class: |
220/367.1 ;
220/200 |
Current CPC
Class: |
B60K 2015/03552
20130101; B60K 2015/03296 20130101; B60K 15/03519 20130101; B60K
15/0406 20130101 |
Class at
Publication: |
220/367.1 ;
220/200 |
International
Class: |
B65D 51/16 20060101
B65D051/16 |
Claims
1. A fuel tank assembly comprising: a fuel tank defining an
interior space; a passive vent that is movable between: (i) an open
position that opens a first air communication path between the
interior space of the fuel tank and the external atmosphere, and
(ii) a closed position that closes the first air communication
path; and an active pressure equalization hardware that
automatically and selectively opens at least a second air
communication paths in response to a pressure difference between
the interior space of the fuel tank and the eternal atmosphere.
2. The assembly of claim 1 wherein the passive vent comprises
biasing hardware shaped, located and/or connected to bias the
passive vent sub-assembly to its closed position.
3. The assembly of claim 1 wherein the active pressure equalization
hardware comprises an air intake valve shaped, structured and
located to automatically and selectively open the second air
communication path between the interior space of the fuel tank and
the external atmosphere when the negative relative pressure in the
interior space of the fuel tank increases in magnitude above a
threshold negative pressure.
4. The assembly of claim 1 wherein the active pressure equalization
hardware comprises a vapor exhaust valve shaped, structured and
located to automatically and selectively open the second air
communication path between the interior space of the fuel tank and
the external atmosphere when the positive relative pressure in the
interior space of the fuel tank increases in magnitude above a
threshold positive pressure.
5. The assembly of claim 1 wherein the active pressure equalization
hardware comprises: an air intake valve shaped, structured and
located to automatically and selectively open the second air
communication path between the interior space of the fuel tank and
the external atmosphere when the negative relative pressure in the
interior space of the fuel tank increases in magnitude above a
threshold negative pressure; and a vapor exhaust valve shaped,
structured and located to automatically and selectively open a
third air communication path between the interior space of the fuel
tank and the external atmosphere when the positive relative
pressure in the interior space of the fuel tank increases in
magnitude above a threshold positive pressure.
6. The assembly of claim 5 further comprising a fuel cap
sub-assembly comprising a removable fuel cap, wherein the passive
vent, the air intake valve and the vapor exhaust valve are all
built into the fuel cap.
7. The assembly of claim 1 further comprising a fuel cap
sub-assembly comprising a removable fuel cap, wherein the passive
vent and the active pressure equalization hardware are built into
the fuel cap.
8. A fuel cap assembly comprising: a removable fuel cap comprising
a first cap member and a second cap member; and fuel cap receiving
hardware connected, shaped and/or located to removably engage the
removable fuel cap; wherein: the removable fuel cap defines a
central axis, an axial direction, an angular direction and a radial
direction; the removable fuel cap and fuel cap receiving hardware
are connected, shaped and/or located so that the removable fuel cap
is removed by turning it in the angular direction and translating
it in the axial direction; the first cap member comprises a
plurality of ratchet teeth; the second cap member comprises at
least one ratchet tooth engaging member; and the plurality of
ratchet teeth face and engage with the at least one ratchet tooth
engaging member in the radial direction.
9. The assembly of claim 8 wherein: the first cap member is an
inner shell member; and the second cap member is an outer shell
member that fits around the inner shell member at least
substantially around the angular direction.
10. A fuel cap assembly for use with a fuel tank, the fuel cap
assembly comprising: a fuel cap; and a tether member made of a
single piece of a single material; wherein: the tether member
comprises a cap-securement portion that is shaped, sized and/or
located to be mechanically secured to the fuel cap; the tether
member further comprises a tethering portion that is shaped, sized
and/or located to: (i) be accommodated within an interior space of
the fuel tank when the fuel cap is engaged to seal the fuel tank,
and (ii) to tether the fuel cap at location(s) spaced apart from a
fueling opening in the fuel tank when the fuel cap is removed from
the fuel tank for fueling; and the tether member further comprises
an anchor portion sized, shaped and/or located to be held within
the interior space of the fuel tank, and prevented by physical
interference from exiting the interior space of the fuel tank
through the fueling opening.
Description
RELATED APPLICATION
[0001] The present application claims priority to U.S. provisional
patent application No. 61/318,842, filed on Mar. 30, 2010; all of
the foregoing patent-related document(s) are hereby incorporated by
reference herein in their respective entirety(ies).
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to fuel tank assemblies, more
particularly to fuel tank assembly for marine vehicles and even
more particularly to fuel cap sub-assemblies for fuel tank
assemblies for marine vehicles.
[0004] 2. Description of the Related Art
[0005] FIG. 1 shows convention fuel tank assembly 100 for a marine
vehicle (not shown), such as a ship or boat. Assembly 100 includes:
tank 102; liquid fuel 104; cap sub-assembly 108; fuel out
sub-assembly 110 and closeable vapor vent 112. In the interior
space of the tank, located above the liquid fuel is vapor space
106. As is understood in the prior art, when this vapor space is
closed off, by sealing the tank in a pressure tight fashion, from
the exterior atmosphere, then the vapor space may develop a
positive pressure or a negative pressure with respect to
atmospheric pressure. For example, if the tank is sealed and the
temperature warms, then the liquid fuel will evaporate into the
vapor space to a greater extent and cause the pressure in the vapor
space to rise above the atmospheric pressure, thereby developing a
positive pressure. As a further example, if the tank is sealed and
liquid fuel is removed from the tank through the fuel out
sub-assembly (for example, to fuel a propulsion engine in the
marine vehicle), then the vapor space will tend to develop a
negative pressure.
[0006] Closeable vapor vent 112 is a prior art solution used to
deal with the interrelated issues of tank sealing and
positive/negative pressure differences. More specifically, it is
often desired to seal the tank in a pressure tight manner so that
liquid fuel and/or fuel vapor does not escape the tank. For
example, if the fuel in the tank will not be used for a long
period, then it is generally desirable to seal the tank to avoid
loss of fuel by evaporation to the atmosphere. On the other hand,
if the tank is sealed then positive or negative pressures can
develop and cause problems. For example, if there is a positive
pressure in the vapor space, then the fuel cap may become difficult
to remove and/or liquid fuel may spray out of the tank when the cap
is removed to unseal the tank. As a further example, if the tank is
sealed when the fuel is being used to fuel an engine, then a
negative pressure may develop and cause the engine to malfunction
due to the increasing difficulty of sucking fuel out of the tank
against the increasing negative pressure.
[0007] Closeable vapor vent 112 is a passive device that allows a
user to prevent and/or deal with positive or negative pressures.
The closable vapor vent allows the user to unseal the tank in a
carefully controlled manner so that air/vapor in the vapor space
can exchange with air of the outside atmosphere. In other words,
when the closeable vapor vent is closed by a user (and the cap is
on), then the tank is sealed. When the closeable vapor vent is
opened by a user, then the tank is unsealed. If there exists a
pressure difference at the time the user opens the closeable vapor
vent, then the pressure difference can be equalized smoothly and
slowly to prevent adverse consequences, such as the spraying of
fuel. If the user leaves the vent open (for example, during periods
when the fuel is being consumed), then pressure differences will
not develop. If the user closes the vent (for example, when the
marine vehicle is in storage), then fuel will not be lost to the
atmosphere, and any pressure difference can be dealt with by
carefully opening the vent before using the marine vehicle
again.
[0008] Although closeable vapor vent 112 is separate from cap 108
in fuel tank assembly 100, it is noted that in some conventional
marine vehicle fuel tank assemblies, the closeable vapor vent and
cap are formed together as a single sub-assembly.
[0009] As mentioned above, the closeable vapor vent of assembly 100
is a passive pressure equalization device because it relies on the
user to decide when it is best to have the vent in the open
position and when to have the vent in the closed position. However,
it has been recognized that this reliance on the user can lead to
problems when the user lacks knowledge or judgement or is
forgetful. In response to this problem, another conventional marine
vehicle fuel tank assembly 200, as shown in FIG. 2, has been
developed. Assembly 200 includes tank 202; liquid fuel 204; cap
sub-assembly 208; fuel out sub-assembly 210; air intake valve 214;
and vapor exhaust valve 216. In assembly 200, vapor space 206 is
generally sealed, except: (i) if a negative pressure goes below
some threshold, then the air intake valve automatically opens
temporarily to allow external, atmospheric air to flow into the
vapor space to equalize the pressure (or at least decrease the
negative pressure somewhat); and (ii) if a positive pressure goes
above some threshold, then the vapor exhaust valve automatically
opens temporarily to allow vapor from the vapor space to flow out
of the tank to equalize the pressure (or at least decrease the
positive pressure somewhat). Assembly 200 is "active" in the sense
that no user intervention is required.
[0010] Although air intake valve 214 and vapor exhaust valve 216
are each separate from cap assembly 208 in fuel tank assembly 200,
it is noted that in some conventional marine vehicle fuel tank
assemblies, one (or both) valves and that cap are formed together
as a single sub-assembly.
[0011] The following publications may be prior art and may be of
interest: (i) US patent ("USP") U.S. Pat. No. 4,265,752
("O'Banion"); (ii) U.S. Pat. No. 5,242,072 ("Koebernik"); (iii)
U.S. Pat. No. 4,922,954 ("Blomquist"); (iv) U.S. Pat. No. 4,666,058
("058 Harris"); (v) U.S. Pat. No. 4,787,529 ("529 Harris"); (vi)
U.S. Pat. No. 5,116,257 ("Szlaga"); (vii) U.S. Pat. No. 4,498,493
("493 Harris"); (viii) U.S. Pat. No. 5,108,001 ("001 Harris"); (ix)
U.S. Pat. No. 6,886,597 ("Dragoni"); (x) U.S. Pat. No. 4,696,409
("Vize"); and (xi) U.S. Pat. No. 4,796,777 ("Keller").
[0012] Description of the Related Art Section Disclaimer: To the
extent that specific publications are discussed above in this
Description of the Related Art Section, these discussions should
not be taken as an admission that the discussed publications (for
example, published patents) are prior art for patent law purposes.
For example, some or all of the discussed publications may not be
sufficiently early in time, may not reflect subject matter
developed early enough in time and/or may not be sufficiently
enabling so as to amount to prior art for patent law purposes. To
the extent that specific publications are discussed above in this
Description of the Related Art Section, they are all hereby
incorporated by reference into this document in their respective
entirety(ies).
BRIEF SUMMARY OF THE INVENTION
[0013] At least some embodiments according to one aspect of the
present invention are directed to a fuel tank assembly that
includes both of: (i) a passive, closeable vent; and (ii) active,
automatic pressure equalization hardware (for example, an air
intake valve and/or a vapor exhaust valve). In at least some
embodiments according to this aspect of the present invention, the
closeable vent is biased in the closed position. The closeable vent
and/or the pressure equalization hardware are preferably built into
the cap assembly.
[0014] According to a further aspect of the present invention, a
fuel cap assembly: (i) defines a central axis, an axial direction,
an angular direction and a radial direction; (ii) includes a fuel
cap that is rotatable in the angular direction about the central
axis; (iii) includes multiple ratchet teeth and ratchet tooth
engagement hardware; and (iv) with the ratchet teeth extending and
engaging with the ratchet tooth engagement hardware in the radial
direction.
[0015] According to a further aspect of the present invention, a
fuel cap assembly includes: (i) a removable fuel cap; (ii) a one
piece tether member; and (iii) the fuel cap and tether assembly are
sized and shaped so that the tether member locks into the removable
fuel cap.
[0016] Various embodiments of the present invention may exhibit one
or more of the following objects, features and/or advantages:
[0017] (i) use of both active and passive hardware to equalize fuel
tank pressure allows the active hardware to be used to accommodate
relatively large pressure differences (positive and/or negative),
while the passive hardware allows a user to have the option of
accommodating pressure differences smaller than those required to
trigger the active hardware;
[0018] (ii) more refined and granular control of fuel tank
pressure;
[0019] (iii) decreases probability that fuel will spray out of tank
and/or end up in the environment;
[0020] (iv) reduces probability that that tethered fuel cap will be
lost;
[0021] (v) reduces cost and/or complexity of tethered fuel cap;
and
[0022] (vi) more space-efficient ratcheted fuel cop; and/or
[0023] (vii) reduces cost and/or complexity of ratcheted fuel
cap.
[0024] According to an aspect of the present invention, a fuel tank
assembly includes: a fuel tank (defining an interior space), a
passive vent and active pressure equalization hardware. The passive
vent is movable between: (i) an open position that opens a first
air communication path between the interior space of the fuel tank
and the external atmosphere, and (ii) a closed position that closes
the first air communication path. The active pressure equalization
hardware automatically and selectively opens at least a second air
communication paths in response to a pressure difference between
the interior space of the fuel tank and the eternal atmosphere.
[0025] According to another aspect of the present invention, a fuel
cap assembly includes: a removable fuel cap; and fuel cap receiving
hardware. The removable fuel cap includes a first cap member and a
second cap member. The fuel cap receiving hardware is connected,
shaped and/or located to removably engage the removable fuel cap.
The removable fuel cap defines a central axis, an axial direction,
an angular direction and a radial direction. The removable fuel cap
and fuel cap receiving hardware are connected, shaped and/or
located so that the removable fuel cap is removed by turning it in
the angular direction and translating it in the axial direction.
The first cap member includes a plurality of ratchet teeth. The
second cap member includes at least one ratchet tooth engaging
member. The plurality of ratchet teeth face and engage with the at
least one ratchet tooth engaging member in the radial
direction.
[0026] According to another aspect of the present invention, a fuel
cap assembly is designed for use with a fuel tank. The fuel cap
assembly includes: a fuel cap; and a tether member (made of a
single piece of a single material). The tether member includes a
cap-securement portion that is shaped, sized and/or located to be
mechanically secured to the fuel cap. The tether member further
includes a tethering portion that is shaped, sized and/or located
to: (i) be accommodated within an interior space of the fuel tank
when the fuel cap is engaged to seal the fuel tank, and (ii) to
tether the fuel cap at location(s) spaced apart from a fueling
opening in the fuel tank when the fuel cap is removed from the fuel
tank for fueling. The tether member further includes an anchor
portion sized, shaped and/or located to be held within the interior
space of the fuel tank, and prevented by physical interference from
exiting the interior space of the fuel tank through the fueling
opening.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The present invention will be more fully understood and
appreciated by reading the following Detailed Description in
conjunction with the accompanying drawings (cross-hatching may be
omitted on cross-section views for clarity of illustration
purposes), in which:
[0028] FIG. 1 is a schematic view of a prior art fuel tank
assembly;
[0029] FIG. 2 is a schematic view of another prior art fuel tank
assembly;
[0030] FIG. 3 is a schematic view of a first embodiment of a fuel
tank assembly according to the present invention;
[0031] FIG. 4 is a schematic view of a second embodiment of a fuel
tank assembly according to the present invention; and
[0032] FIG. 5 is a cross section view of a portion of a first
embodiment of cap sub-assembly of the second embodiment fuel tank
assembly;
[0033] FIG. 6 is a perspective view of a component of the first
embodiment cap assembly;
[0034] FIG. 7 is a perspective view of a portion of the first
embodiment cap sub-assembly;
[0035] FIG. 8 is a perspective view of a portion of the first
embodiment cap sub-assembly;
[0036] FIG. 9 is a perspective view of a portion of the first
embodiment cap sub-assembly;
[0037] FIG. 10 is a perspective view of a portion of the first
embodiment cap sub-assembly;
[0038] FIG. 11 is a perspective view of a portion of the first
embodiment cap sub-assembly;
[0039] FIG. 12 is a perspective view of a portion of the first
embodiment cap sub-assembly;
[0040] FIG. 13 is a perspective view of a second embodiment cap
sub-assembly suitable for use in the first embodiment fuel tank
assembly;
[0041] FIG. 14 is a perspective view of a portion of the second
embodiment cap sub-assembly;
[0042] FIG. 15 is a perspective view of a portion of the second
embodiment cap sub-assembly;
[0043] FIG. 16 is a cross section view of a portion of the second
embodiment cap sub-assembly;
[0044] FIG. 17 is a perspective view of a portion of the second
embodiment cap sub-assembly;
[0045] FIG. 18 is a perspective view of a portion of the second
embodiment cap sub-assembly;
[0046] FIG. 19 is a perspective view of a portion of the second
embodiment cap sub-assembly;
[0047] FIG. 20 is a cross section view of a portion of the second
embodiment cap sub-assembly;
[0048] FIG. 21 is a cross section view of a portion of the second
embodiment cap sub-assembly; and
[0049] FIG. 22 is a perspective view of a portion of the second
embodiment cap sub-assembly.
DETAILED DESCRIPTION OF THE INVENTION
[0050] FIG. 3 shows fuel tank assembly 300 for a marine vehicle
(not shown), such as a ship or boat. Assembly 300 includes: tank
302; liquid fuel 304; cap sub-assembly 308; fuel out sub-assembly
310; active pressure equalization hardware 315; and passive,
biased-closed vent 350. In the interior space of the tank, located
above the liquid fuel is vapor space 306. In this embodiment, the
active pressure equalization hardware actively equalizes positive
and/or negative vapor space pressure that goes above a certain
positive pressure threshold and/or negative pressure threshold. In
other words, the pressure equalization hardware may automatically
respond to only positive pressure, only negative pressure or both
positive and negative pressure. In variations where the pressure
equalization hardware actively responds to both positive and
negative pressure, the positive and negative pressure thresholds
may or may not have the same magnitude. The active hardware may use
automatic valve(s) or any other suitable active pressure equalizing
hardware now known, or to be developed in the future. In variations
where the pressure equalization hardware actively responds to both
positive and negative pressure, the air communication path may or
may not be the same for positive and negative pressure
equalizations. For example, in embodiments where the pressure
equalization hardware includes a separate air intake valve and
vapor exhaust valve, the air communication paths will be different
for active positive and negative pressure adjustments.
[0051] FIG. 4 shows fuel tank assembly 400 for a marine vehicle
(not shown), such as a ship or boat. Assembly 400 includes: tank
402; liquid fuel 404; cap sub-assembly 408; and fuel out
sub-assembly 410. Cap sub-assembly 408 includes air intake valve
414; vapor exhaust valve 416; and biased closed vent 450. In the
interior space of the tank, located above the liquid fuel is vapor
space 406. In assembly 400, the air intake valve and the vapor
exhaust valve provide active pressure equalization. In assembly
400, the biased closed vent is a passive vent which is operated by
a user. More specifically, the user can hold the biased closed vent
in an open position to allow the pressure in the vapor space to
equalize to atmospheric pressure. Because the vent is biased
closed, the vent will return to a closed position, to seal the
tank, when a user is not holding it open. Assembly 400 allows
relatively large positive or negative pressure differences to be
equalized automatically, but also allows a user to equalize smaller
pressure differences that are not sufficiently large to
automatically open the valve(s).
[0052] The operation of fuel cap assembly 408 will now be discussed
in more detail in connection with FIGS. 5 to 12. As shown in FIGS.
5 to 12, fuel cap assembly 408 includes: outer shell member 408a;
inner shell member 408b; tether member 408c; housing portion 455
(of inner shell member); containment piece engagement portion 456
(of inner shell member); containment piece 458; first spring 460;
elastomer ball 462; second spring 464; first slot channels 466
(defined in manual release button member); manual release button
member 468; elastomer ball prod portion 470 (of the manual release
button member); flange 472; second slot channels 474 (defined in
manual release button member); ratchet teeth 475 (of the inner
shell member); tether engagement slot 476 (of the inner shell
member); tether-to-cap securing portion 480 (of the tether member);
tethering leash portion 481 (of the tether member); anchor portion
482 (of the tether member); ratchet tooth engagement portions 490
(of the outer shell member); button receiving aperture 491 (of the
outer shell member); elastomer ball receiving aperture 492. The
elastomer ball is preferably made of viton.
[0053] The fuel cap controls vapor emissions by a system of valves.
The intake valve allows ambient atmosphere into the tank to replace
the volume of fuel consumed by the motor the intake valve doesn't
allow vapors to escape. The exhaust valve will allow vapors to
pressurize up to 5 PSI and release into the atmosphere above 5 PSI.
The manual release valve allows the user to relieve any built up
pressure in the tank to connect or disconnect fuel hoses, remove
the cap, etc., safely without spraying or spilling liquid fuel. The
cap contains a ratcheting feature to give the user an audible and
tactile indication that the cap is seated and sealed properly on
the tank. The tether assembly protects the valves from direct
contact with liquid fuel due to splashing within the tank. Cap
design is such that any vapors released through the bottom of the
cap to minimize exposure to the user. The manual release valve is
normally closed unless pressure is applied by the user. When the
user removes the pressure to the button, it automatically releases
and allows the valve to close using 2 sets of springs.
[0054] As shown in FIG. 5, second spring 464 maintains manual
release button member 468, and its elastomer ball prod portion 470,
in a raised position spaced away from elastomer ball 462. In this
raised position, flange 472 is pushed up against the edge of button
receiving aperture 491 (see FIG. 11) so that the tank, and its
vapor space, is sealed in a pressure tight fashion so longs as no
user is manually releasing by pressing down on the release
button.
[0055] When a user does press down on the exposed top of the
release button member (in the direction of arrow P), then the
button member and flange its flange are forced down to a lowered
position against the bias of second spring 464 and first spring
460. In the lowered position, the vapor space comes into fluid
communication with the external atmosphere. If there is a positive
pressure in the vapor space, the vapor can escape through the space
between the flange of the button member and the edge of the button
receiving aperture. If there is negative pressure, then atmospheric
air will be sucked into the vapor space in the opposite direction
over the same air communication path.
[0056] When the manual release button is forced down to the lowered
position, the venting path for air communication is shown by the
thick, red, dotted curve as shown in FIG. 5. In the FIG. 5 view,
some portions of the dotted curve lie within the cross sectional
profile of button member 468 itself. This is possible because, as
best shown in FIG. 6, the button member has defined therein first
slot channels 466; second slot channels 474; and a cruciform shaped
elastomer ball prod portion 470. These slot channels, and the
channels effectively formed by the cruciform prod allow air to
travel within the interior space of the button member between the
vapor space and the exterior atmosphere. In order for the air
communication path shown in FIG. 5 to remain open: (i) flange 472
must be pushed down and away from button receiving aperture 491;
and (ii) elastomer ball prod portion 470 must be sufficiently
pushed down to prod elastomer ball 462 down and away from
engagement with elastomer ball receiving aperture 492. When a user
releases the button member, then first spring 460 forces elastomer
ball 462 back up against elastomer ball receiving aperture to block
the air communication path shown in FIG. 5 so that vapor space 406
is pressure-tight-sealed once again.
[0057] As best shown in FIGS. 7, 11 and 12, the ratchet teeth 475
and ratchet tooth engagement portions 490 face and engage in the
radial direction R (see FIG. 12). This is different than
conventional ratcheted designs where the teeth face and engage in a
direction parallel to the axial direction defined by the central
axis of rotation of the fuel cap.
[0058] As best shown in FIGS. 8-10, the tether-to-cap securing
portion 480 of tether member 408c snap fits into tether engagement
slot 476. Tethering leash portion: (i) extends into the interior
space of the fuel tank when the fuel cap is secured to close the
fuel tank; and (ii) extends out of the fuel tank to tether the fuel
cap when the fuel cap is opened. Anchor portion 482 is shaped to
prevent the tether member from being completely removed from the
fuel tank so that fuel cap remains tethered even when it is away
from the vicinity of the opening in the fuel tank through which
additional fuel is introduced. One thing to note about the design
of tether member 408c is that it is preferably a single piece of a
single material. This is preferable to conventional rope tethers
that anchored in interior space of the fuel tank (like the design
of FIGS. 8 to 10), but are made up of multiple piece parts because
the material that is used to make the rope is generally not
suitable to secure the tether to the cap or to make an anchor. This
is also preferable to any conventional designs that may anchor, or
otherwise be secured to, a location outside of the fuel tank
because extra hardware will be required to make this securement
because these externally secured designs do not use the fuel
opening itself to restrain the tether on the fuel tank side.
[0059] The tether design of FIGS. 8 to 10 will generally not
provide a tether that is as flexible as a conventional rope style
tether. However, the tether needs to be relatively flexible, and is
preferably sufficiently flexible so that the weight of the fuel cap
will bend the tether downwards so that the fuel cap will lean down
against the side of the tank when the cap is removed from the tank.
This flexibility can be achieved by carefully choosing: (i) the
material of the single piece tether member; and (ii) the tether
cross sectional area and profile. Preferably, the single piece
tether of the present invention is made of a gasoline resistant
polymer. One currently-preferred material is acetal.
[0060] The fuel cap assembly of FIGS. 13 to 23 is believed to have
lower tooling costs than the fuel cap assembly embodiment 408
discussed above in connection with FIGS. 5 to 12. FIGS. 13 to 22
show fuel cap assembly 500, including: outer shell 502; shunt value
safety seal 504; manual release button ring 506; viton ball 508;
spring 510; spring retainer 512; inner cap 514; intake value 516;
exhaust value 518; gasket 520; tethered assembly 522; tether 524;
button guard 526; alignment hole 528; inserts 530; snap attachment
for tether 532; vent hole 534; spin or sonic weld 536; gasket seal
538; snap portion 540; ridges portion 542; contour portion 544;
seal seat 546; inside threads for exhaust valve 548; hole for
exhaust value feature 550; inner threads for tank 552; ring support
post 554; intake hole 556; exhaust valve seal feature 558; voided
outer threads 559; five psi valve 560; and manual release feature
562.
[0061] As shown in FIG. 15, inserts 530 in the hole in the inner
shell move the viton ball down against the spring.
[0062] As shown in FIG. 18: (i) snap portion 540 snaps into
tethered assembly part 522; (ii) ridges portion 542 render the
tether somewhat flexible so that it will hang downwards over the
side of the vehicle and out of the way when a user is refilling the
fuel tank; and (iii) contour portion 544 is contoured to match the
interior of the fuel tank opening.
[0063] As shown in FIG. 19: (i) seal seat 546 should preferably be
capable of reliably holding 20 psi of pressure when twisted down;
and (ii) inside threads for exhaust valve 548 match voided threads
on exhaust valve feature of the inner cap.
[0064] As shown in FIG. 21: ring support post 554 supports the
manual release ring; (ii) intake hole 556 may not be needed in all
embodiments of the present invention; (iii) spring retainer 512 may
be a snap piece or it may be sonically welded.
DEFINITIONS
[0065] Any and all published documents mentioned herein shall be
considered to be incorporated by reference, in their respective
entireties, herein to the fullest extent of the patent law. The
following definitions are provided for claim construction
purposes:
[0066] Present invention: means at least some embodiments of the
present invention; references to various feature(s) of the "present
invention" throughout this document do not mean that all claimed
embodiments or methods include the referenced feature(s).
[0067] Embodiment: a machine, manufacture, system, method, process
and/or composition that may (not must) meet the embodiment of a
present, past or future patent claim based on this patent document;
for example, an "embodiment" might not be covered by any claims
filed with this patent document, but described as an "embodiment"
to show the scope of the invention and indicate that it might (or
might not) covered in a later arising claim (for example, an
amended claim, a continuation application claim, a divisional
application claim, a reissue application claim, a re-examination
proceeding claim, an interference count); also, an embodiment that
is indeed covered by claims filed with this patent document might
cease to be covered by claim amendments made during
prosecution.
[0068] First, second, third, etc. ("ordinals"): Unless otherwise
noted, ordinals only serve to distinguish or identify (e.g.,
various members of a group); the mere use of ordinals shall not be
taken to necessarily imply order (for example, time order, space
order).
[0069] Mechanically connected: Includes both direct mechanical
connections, and indirect mechanical connections made through
intermediate components; includes rigid mechanical connections as
well as mechanical connection that allows for relative motion
between the mechanically connected components; includes, but is not
limited, to welded connections, solder connections, connections by
fasteners (for example, nails, bolts, screws, nuts, hook-and-loop
fasteners, knots, rivets, quick-release connections, latches and/or
magnetic connections), force fit connections, friction fit
connections, connections secured by engagement caused by
gravitational forces, pivoting or rotatable connections, and/or
slidable mechanical connections.
[0070] To the extent that the definitions provided above are
consistent with ordinary, plain, and accustomed meanings (as
generally shown by documents such as dictionaries and/or technical
lexicons), the above definitions shall be considered supplemental
in nature. To the extent that the definitions provided above are
inconsistent with ordinary, plain, and accustomed meanings (as
generally shown by documents such as dictionaries and/or technical
lexicons), the above definitions shall control.
[0071] Unless otherwise explicitly provided in the claim language,
steps in method steps or process claims need only be performed in
the same time order as the order the steps are recited in the claim
only to the extent that impossibility or extreme feasibility
problems dictate that the recited step order be used. This broad
interpretation with respect to step order is to be used regardless
of whether the alternative time ordering(s) of the claimed steps is
particularly mentioned or discussed in this document--in other
words, any step order discussed in the above specification shall be
considered as required by a method claim only if the step order is
explicitly set forth in the words of the method claim itself. Also,
if some time ordering is explicitly set forth in a method claim,
the time ordering claim language shall not be taken as an implicit
limitation on whether claimed steps are immediately consecutive in
time, or as an implicit limitation against intervening steps.
* * * * *