Note: Descriptions are shown in the official language in which they were submitted.
CA 02291906 1999-12-07
DISPOSAL FUEL FILTER ELEMENT AND LID ASSEMBLY
This application claims the benefit of U.S. Provisional Application No.
60/111,877, filed 12/11/98
Field Of The Invention
The present invention generally relates to fuel filters and more
particularly relates to replaceable filter elements for fuel filters.
Background Of The Invention
Fuel filters for internal combustion engines, such as those used on
motor vehicles, commonly include a housing to which the fuel to be filtered is
directed, as well as a replaceable filter element which resides within the
filter
housing. The replaceable filter element provides the medium through which
the fuel is passed to screen or filter contaminants from the fuel.
A variety of fuel filter designs are currently known, with U.S. Patent
No. 5,770,065 disclosing a substantially cylindrical housing having a closed
end and an open end with a removable lid being threadably attached to the
open end of the cylindrical housing. A standpipe extends from the closed end
of the housing to the open end, and includes an operable fuel valve in the
upper end of the standpipe. An annular shaped replaceable filter element
having a pleated filter ring and a pair of end caps is disposed around the
standpipe. A projection is affixed to the upper end cap of the replaceable
filter element which is adapted to enter the standpipe and actuate the valve
when the replaceable filter element and removable lid are in operable
position.
The end cap of the replaceable filter element includes a pair of deformable
fingers which cooperate with apertures provided in the removable lid to
CA 02291906 1999-12-07
2
removably attach the filter element to the lid such that when the lid is
removed, the replaceable filter element is removed as well to thereby allow
the replaceable filter element to be thrown away, and for a clean filter
element
to be reattached to the lid for subsequent use.
In addition, U.S. Patent No. 5,049,269 sets forth a fuel filter design
analogous to the '065 patent, except for provision of the valve actuation
projection on the lid of the fuel filter. More specifically, the '269
discloses
the same basic filtering principles as the '065, but for the positioning of
the
valve actuating projection on the filter lid. This is in. opposition to the
'065
patent which, as indicated above, provides its valve actuation projection on
the end cap of the replaceable filter element, not on the fuel filter housing
lid.
While such a filter arrangement is workable, it is not without
drawbacks. For example, with regard to the '065 patent, when the replaceable
filter element is full and needs to be replaced, the person servicing the
engine
must remove the lid and filter element, and inwardly depress the plastic
fingers on the end cap of the filter element to release the filter element for
disposal purposes. In so doing, the hands of the operator often come in
contact with the filter element itself which is normally quite soiled,
resulting
in a mess. Moreover, the retaining fingers on the end cap themselves may
become soiled, again resulting in a mess on the hands of the operator. Given
the location and structure of the fingers, they are also susceptible to
breakage,
thereby making filter element removal difficult.
In addition, a loose sealing gasket is typically provided with the service
element, intended to be installed between the outer periphery of the removable
lid and outer circumference of the open end of the fuel housing. In keeping
with best practice within the industry, it is the intention that this loose
gasket
be replaced at each service interval, however, there is no guarantee that this
will happen. First, because the used gasket is soiled with diesel fuel and
other
CA 02291906 1999-12-07
contaminants, the operator may attempt to reuse the gasket simply in order to
lessen the mess associated with the change. Another reason that the gasket
might not be replaced is that the supplied gasket may have a beveled edge on
it, where proper orientation of this gasket is critical but unfortunately, not
obvious. Improper orientation may lead to fuel leaks and overall poorer
performing engines. By leaving the used gasket in place, the operator appears
to resolve the problem of improper orientation, but in doing so, can create
the
very leaks they were trying to avoid, since it is well known that used gaskets
typically do not seal with the same integrity as a virgin gasket. Finally,
during
subsequent servicing of the filtering element, this loose gasket can fall into
the
interior of the filter housing and become lodged around delicate internal
components, making extraction difficult and perhaps even damaging to said
internal components.
Furthermore, since the lid is reused and only the replaceable filter
element is discarded, the aforementioned lid, which is typically made of
plastic, is prone to fatigue and premature failure. The gradual weakening of
the lid can be exacerbated by the various fuel additives commonly found in
diesel fuel, particularly those marketed as winter driving aids. And in fact,
the
very act of applying sufficient loosening torque to the lid, through the small
projecting tabs, may cause it to break during servicing. In addition, it is
also
possible that the lid get misplaced, lost, or otherwise damaged while removed
from the vehicle, and it has been found that such lids are often difficult and
expensive to replace as they are not commonly maintained in inventory. This
necessarily equates to downtime for the internal combustion engine, of which
the fuel filter is a part, until such a replacement lid is obtained.
The engine can also be subjected to downtime, and the motorist can be
stranded as a result, if the replacement filter element becomes plugged
without
a replacement element being readily available. In other words, since such
CA 02291906 1999-12-07
4
replacement filter elements include the actuation projection to operate the
fuel
valve within the standpipe, with such a design the fuel filter and thus the
engine is inoperable unless the replacement filter element is operable as
well.
The engine cannot operate with the plugged replacement filter element simply
removed and the replacement lid attached to the filter housing because no
mechanism is provided to open the fuel valve within the standpipe.
In addition to these difficulties, it would be beneficial if the central area
of the replaceable filter element end cap were to be opened to allow for
various sensors, heaters, vents, valves, etc., to be inserted through the
removable lid of the fuel filter to the center portion of the filter element.
It
would also be beneficial if the entire fuel filter element and lid assembly
could
be manufactured quickly and at a minimum of expense.
Summary Of The Invention
It is therefore an objective of the present invention to provide a fuel
filter element and lid assembly which substantially eliminates contact between
an operator and a soiled filter element when replacing the filter element.
It is another objective of the present invention to avoid downtime for
an internal combustion engine using such a fuel filter due to the removable
lid
of the fuel filter being lost or broken.
It is another objective of the present invention to provide a fuel filter
assembly which provides a mechanism by which a motorist can avoid being
stranded and can navigate to a nearby service station even if the replaceable
filter element becomes plugged and another element is not readily available.
It is another objective of the present invention to provide a fuel filter
wherein the filter lid and outer sealing gasket can be discarded and replaced
every time the filter element itself is discarded and replaced.
CA 02291906 1999-12-07
S
It is another objective of the present invention to provide a fuel filter
and replaceable filter element and lid assembly which reduces the total force
required to remove the element from the standpipe of the fuel filter housing.
It is a still further objective of the present invention to provide a fuel
filter having a mechanism by which various sensors, heaters, valves, and vents
can be easily inserted to the center portion of the filter element.
In accordance with these objectives, it is a feature of a preferred
embodiment of the present invention to provide a replaceable filter element
and removable lid assembly which is discarded and replaced every time the
filter element needs to be changed. In so doing, the removable lid is less
prone to breakage and is less likely to be lost. Moreover, since the lid and
element are discarded every time, the operator need not come in contact with
the soiled filter element. Rather, the element and lid assembly can simply be
discarded, and a new, clean, element and lid assembly can be installed.
In accordance with such a preferred embodiment of the present
invention, it is a feature to provide the outer sealing gasket for such a fuel
filter in a substantially fixed arrangement with the housing lid such that it
is
discarded and replaced every time the filter element and lid are replaced as
well. In so doing, the operator need not come in contact with a soiled gasket
and the gasket is not prone to being lost, damaged, or installed incorrectly.
It is another feature of a preferred embodiment of the present invention
to rely on the leverage of the screw threads on the removable lid to pull the
replaceable filter element away from the filter housing standpipe when
unscrewing the lid to thereby reduce the total force required to remove the
replaceable filter element from the housing. Since the replaceable filter
element rotates with the removable lid, the leverage of the screw threads
reduces the force required for removing the replaceable filter element from
the
standpipe.
CA 02291906 1999-12-07
6
It is a still further feature of a preferred embodiment of the present
invention to provide the end cap of the replaceable filter element with a
central open area and to seal the replaceable filter element against a central
protruding hub of the removable lid such that various sensors, heaters, vents,
and valves can be inserted through a lid into the center portion of the filter
element.
It is a still further feature of a preferred embodiment of the present
invention to manufacture the aforementioned replaceable filter element and lid
assembly in an efficient and economical manner. Toward that end, the
removable lid can be molded from two separate plastic pieces which are then
ultrasonically welded together. The lid can be comprised of a planar cap
portion as well as a plurality of downwardly depending and radially
deformable fingers which substantially attach the filter element to the
removable lid.
These and other objectives and features of the invention will become
more apparent from the following detailed description when taken in
conjunction with the accompanying drawings.
Brief Descriution Of The Drawings
FIGURE 1 is a side view of a preferred embodiment of the present
invention;
FIG. 2 is a sectional view of FIG. 1;
FIG. 3 is a cut-away perspective view of a preferred embodiment of the
present invention installed in a conventional fuel filter having a standpipe;
FIG. 4 is an enlarged side view of a preferred embodiment of the
removable lid;
FIG. 5 is a bottom view of FIG. 4;
CA 02291906 1999-12-07
FIG. 6 is a sectional view of FIG. 5 taken along the line 6-6;
FIG. 7 is a perspective view of the deformable finger hub prior to
attachment to the removable lid;
FIG. 8 is a top view of the replaceable filter element end cap;
FIG. 9 is a sectional view of FIG. 8 taken along the line 9-9;
FIG. 10 is an enlarged sectional view of the nexus between the
removable lid, cylindrical fuel filter housing, and outer sealing gasket
attached
to the removable lid;
FIG. 11 is a sectional view of an alternative embodiment of the present
invention;
FIG. 12 is a perspective view of the replaceable filter element end cap
used in conjunction with the alternative embodiment of FIG. 11;
FIG. 13 is a perspective sectional view of FIG. 12;
FIG. 14 is a perspective sectional view of the lid attached to the filter
housing without a filter element installed; and
FIG. 15 is sectional view of the entire filter housing having the present
invention installed.
While the invention is susceptible of various modifications and
alternative constructions, certain illustrative embodiments thereof have been
shown in the drawings and will be described below in detail. It should be
understood, however, that there is no intention to limit the invention to the
specific forms disclosed, but on the contrary, the intention is to cover all
modifications, alternative constructions and equivalents falling within the
spirit and scope of the invention as defined by the appended claims.
CA 02291906 1999-12-07
g
Detailed Description Of The Preferred Embodiment
Referring now to the drawings and with specific reference to FIG. l, a
preferred embodiment of the present invention is generally depicted as
replaceable filter element and removable lid assembly 20. As shown therein,
assembly 20 includes replaceable filter element 22 as well as lid 24. In the
preferred embodiment, filter element 22 is substantially annular in shape and
includes a ring of filter media 26 having first and second end caps 28 and 30
bonded thereto. As best shown in FIG. 2, ring of filter media 26 defines a
central cylindrical opening in which perforated core 32 is disposed. In the
preferred embodiment of the present invention, filter media 26 is
manufactured from paper whereas first and second end caps 28 and 30 are
metal, although in alternative embodiments, other materials including plastics
can be used.
Turning now to FIG. 3, assembly 20 is shown attached to fuel filter
housing 34 having a substantially cylindrical side wall with open end 36 and a
closed end 37 opposite thereto and shown in FIG. 15. Standpipe 38 is
centrally disposed within housing 34 and extends from the closed end. A
valve member is adapted to be disposed within cavity 40 and is able to move
linearly therein. The valve member is normally biased upwardly to close
opening 42 but can be downwardly depressed to open the valve to allow fuel
to exit the filter itself.
In the preferred embodiment of the present invention, it can be seen
that the mechanism by which the valve is opened is provided in the form of
projection 44 which is integrally molded to lid 24. Projection 44 is
sufficiently long to extend through end cap 28, enter standpipe 38, and
downwardly depress the valve member. To accommodate such interaction, it
can be seen that in the preferred embodiment of the present invention, end cap
CA 02291906 1999-12-07
9
28 includes a central opening 46, as best shown in FIGS. 8 and 9. Not only
does central opening 46 allow for the projection 44 to pass through, but in so
doing, the end caps of filter element 22 are simple in design and can thus be
manufactured relatively inexpensively.
In order to provide a seal between lid 24 and filter element 22, the
preferred embodiment of the present invention includes central hub 48
comprised of a cylindrical wall with a stepped shoulder 50 about its lower
periphery. Central hub 48 is sized to be received within central opening 46 of
end cap 28 with bottom 52 of central hub 48 abutting radially inwardly
directed plateau 54 of end cap 28. In so doing, stepped shoulder 50 defines an
annular groove into which an elastomeric o-ring 56 is disposed for sealing
purposes.
As best shown in FIGS. 5 and 6, lid 24 also includes deformable
retention ring 58. More specifically, ring 58 includes circular base 60 from
which a plurality of elastically deformable fingers 62 downwardly depend.
Each finger 62 includes radially outwardly extending rib 64 having cam
surface 66 and locking ledge 68, the importance and function of which will be
described in further detail herein.
In the preferred embodiment of the present invention, FIGS. 3, 6, and 7
show that deformable ring 58 is separately molded from lid 24. Preferably,
ring 58 is molded from the same plastic, such as glass filled nylon as lid 24.
After the ring 58 and lid 24 are separately molded, they are preferably
ultrasonically welded at 70 to form a complete unit. Alternatively, adhesive
bonding, or other mechanisms, can be used for attaching ring 58 to lid 24. In
still further embodiments, ring 58 and fingers 62 can be integrally molded
with lid 24.
Referring again to FIGS. 2 and 3, the process by which assembly 20 is
assembled will be discussed in detail. As disclosed earlier, lid 24 includes
CA 02291906 1999-12-07
central hub 48 having o-ring receiving shoulder 50. In the preferred
embodiment, once deformable ring 58 is ultrasonically welded to lid 24,
elastomeric o-ring 56 is inserted over central hub and into stepped shoulder
50. Once o-ring 56 is in place, a separate filter element 22, having end caps
5 28 and 30 already adhesively attached thereto, is inserted over central hub
and
elastomeric o-ring 56. More specifically, central opening 46 of end cap 28 is
directed toward projection 44. The apex 72 of each deformable finger 62 is
dimensioned to be received within central opening 46 of end cap 28. As filter
element 22 is further depressed toward lid 24, cam surfaces 66 engage plateau
10 54 which causes deformable fingers 62 to move radially inwardly. Fingers 62
continue to move radially inwardly until locking ledge 68 moves past plateau
54, at which time, the elastic properties of fingers 62 cause fingers 62 to
spring radially outwardly past plateau 54. At such point, lid 24 cannot easily
be removed from filter element 22 because plateau 54 is trapped between the
locking ledges 68 of deformable fingers 62, and the bottom 52 of central hub
48. If it is necessary to remove filter element 22 from lid 24, special
tooling
can be inserted through second end cap 30 to inwardly depress deformable
fingers 62 until locking ledges 68 can be moved past plateau 54. However, in
the preferred embodiment of the present invention, it is not necessary to
remove filter element 22 from lid 24, and in fact it is not desirable in that
the
present invention is directed toward an assembly 20 which can be entirely
discarded when filter element 22 is filled with contaminants filtered from the
fuel passing through the filter.
In other words, after a period of operation which causes filter element
22, and more specifically ring of filter media 26, to become filled or clogged
with contaminants filtered from the fuel passing through an engine, the filter
element 22 and lid 24 can be removed as assembly 20 for easy replacement
purposes. Since the operator need not remove filter element 22 from lid 24,
CA 02291906 1999-12-07
the operator is not subjected to a soiled mess, but rather a new, clean,
assembly 20 can simply be reinstalled.
To facilitate removal of assembly 20, it can be seen from FIGS. 1 and 4
that lid 24 includes reduced diameter cylinder 74 having a plurality of
threads
76. In a preferred embodiment of the present invention, threads 76 are male
threads which are adapted to be received within the female threads of filter
housing 34, although in alternative embodiments, different types of thread
configurations or attachment mechanisms can be utilized. However, it is
important to note that upon rotation of lid 24, the present invention utilizes
the
leverage generated by the rotation of lid 24 and the interaction of the
threads
to pull filter element 22 away from standpipe 38. The force required is
increased due to elastomeric grommet 78 attached to second end cap 30.
Grommet 78 includes central opening 80 which seals against standpipe 38.
Lid 24 includes hexagonal nut 79 with tool receiving groove 81 to facilitate
use of a conventional wrench or screwdriver in rotating lid 24. Lid 24 also
includes fins 83.
Not only do lid 24 and filter element 22 get discarded when changing
assembly 20, but in the preferred embodiment of the present invention, outer
sealing gasket 82 is discarded as well. As shown in FIGS. 4 and 10, gasket 82
is retained on reduced diameter cylinder 74 above threads 76 and below planar
area 84. In the preferred embodiment of the present invention, sealing gasket
82 relies on its elastic properties and on angled ridge 86 to retain sealing
gasket 82 to lid 24. In the preferred embodiment of the present invention,
angled ridge 86 is disposed at approximately eighty degrees relative to planar
area 84. Therefore, when assembly 20, including filter element 22 and lid 24
are rotated relative to housing 34 and the entire assembly 22 is removed from
standpipe 38, sealing gasket 82 is retained by lid 24 to avoid the
aforementioned problems associated with prior art devices. More specifically,
CA 02291906 1999-12-07
12
with prior art devices, it had been found that such a sealing gasket could
easily
be lost or damaged during the replacement process, or be installed
incorrectly.
In addition, since the sealing gaskets in prior art devices are not attached
to
the lid or the housing, the operator necessarily has to reorient the gasket
every
time the filter element is removed and replaced. Since the gasket is oily and
soiled, this causes another opportunity for the operator to be confronted with
a
mess.
While FIG. 3 does depict the present invention as assembly 20 installed
within housing 34, it is to be understood that since projection 44 is part of
lid
24, the fuel filter and thus the internal combustion engine can be operable
without filter element 22. In other words, as shown in FIG. 14, if lid 24 were
to be attached to filter housing 34 without a filter element 22 being attached
to
lid 24, projection 44 would still be able to enter standpipe 38 and operate
the
valve held therein. While this would subject the engine to operation without
filtered fuel, it would prevent the motorist from being stranded should the
filter element become plugged without a replacement element being readily
available. Such is not possible with prior art devices which rely on the
projection being part of the fuel filter element end cap to operate the valve.
If
such a prior art filter element were to become plugged, and a replacement
element were not to be readily available, the fuel filter and the engine would
not be operable, thus subjecting the motorist to downtime until such time that
a replacement element can be obtained.
The present invention also endeavors to provide a filter element having
a central open area defined by core 32, with the filter element 22 being
sealed
against central hub 48 of lid 24. In so doing, various types of sensors,
heaters,
valves, vents, and the like, can be inserted through the central portion of
lid 24
to the center portion of the filter element for various purposes. Such
features
are not available with known prior art devices.
CA 02291906 1999-12-07
13
FIGS. 11-l3 depict an alternative embodiment of the present invention.
As shown best in FIG. 11, lid 24 of the alternative embodiment does not
include deformable ring 58, but rather includes inner hub 88. Inner hub is
substantially cylindrical in shape and is sufficiently long to extend past
plateau 54 of end cap 28. This is of importance in that end cap 28,
specifically plateau 54, further includes gripping tabs 90 which serve to hold
lid 24 to replaceable filter element 22. More specifically, as shown in FIGS.
12 and 13, tabs 90 are angled downwardly with respect to plateau 54 and are
separated by gaps 92 to facilitate insertion of inner hub 88 into central
opening 46. Upon force being directed to pull lid 24 away from end cap 28,
gripping tabs 90 dig into inner hub 88 to resist such separation. In the
preferred embodiment of the present invention, tabs 90 are manufactured from
steel and inner hub 80 is manufactured from plastic to facilitate the gripping
action. Moreover, inner hub 88 is slightly frusto-conical in shape to assist
the
insertion process.
With the alternative embodiment, it can be seen that inner hub 88 can
be integrally molded with lid 24 to thereby result in relatively low
manufacturing costs. In other words, a separate mold for deformable ring 58
is eliminated, as is the ultrasonic welding or other adhesion process
associated
therewith. The remainder of assembly 20 of the alternative embodiment is the
same as the preferred embodiment depicted above.
From the foregoing, it can therefore be seen that the present invention
provides a new and improved replaceable fuel filter element and removable
lid assembly for use in conjunction with a fuel filter of the type having a
centrally disposed standpipe and valve structure. Since the replaceable filter
element and lid form a complete assembly, every time the element is filled or
plugged, the entire assembly can be removed from the filter housing,
discarded, and replaced with a new assembly. The operator is not subjected to
CA 02291906 1999-12-07
14
a messy process of removing the assembly from the lid as is the case with
prior art devices. Moreover, since a new lid is provided with each filter
assembly, the lid itself will not be lost or subjected to breakage which can
often result in substantial downtime with prior art devices where the lid is
reusable and the filter element is replaced every time. Moreover, since the
outer sealing gasket is affixed to the lid of the assembly, it is discarded
every
time the assembly is discarded and the operator need not be concerned with
losing the sealing gasket, damaging the sealing gasket, or installing the
gasket
incorrectly. Again, since the gasket is affixed to the ring, it will not be
necessary for the operator to come in contact with a soiled gasket when
replacing the filter element. As an added emergency feature, in the event that
a filter element should become plugged, and a replacement filter element
should prove not to be readily available, the present invention allows a
conventional fuel filter to be operable in that the standpipe valve actuation
projection is part of the removable lid and not the filter element itself.
Furthermore, through the efficient design of the present invention, the
components of the present invention can be separately molded and
ultrasonically welded together to form a complete lid unit which can then be
physically attached to a conventional filter element having first and second
annular end caps. Complicated structures associated with the end caps are
thereby avoided resulting in a reduced expense and quicker production time.
As an even further simplification of the means for attaching the
filtering element to the housing lid, the sheet steel element end cap and
integral gripping tabs can be formed in the same stamping operation. This
achieves even greater manufacturing efficiencies by eliminating the need for
the separately molded deformable ring and the subsequent ultrasonic weld or
adhesive bond formation.
