Note: Descriptions are shown in the official language in which they were submitted.
~ BACKGROUND OF THE INVENTXOM ~175~81
This invention relates generally to gaskets and more
particularly as reference to a ledge gasket adapted for use
in a filter element.
Pertinent United S~ates and foreign patents are ~ound
in Class 55, subclasses 492, 493, 498, 502, 509 and 510 and Class
210, subclasses 450, 454 and 459 of the oficia-l classifications
of patents in the Uni~ed States Patent and Trademark Of~ice.
Examples of pertinent patents are United States Patent
Nos. 4,128,251; 4,056,876; 3,877,910; 3,399,516; 2,871,976 and
2,732,031.
U.S. Patent No. 4,128,251 discloses a sealing gasket
for an air filter. The gasket, preferably made of plastisol,
has a soft base portion that provides a seal between the
gasket and the filter medium.
In U.S. Patent No. 4,056,876, a hot-melt adhesive is
used to attach a rim to a filter element. A tight seal is
formed when the adhesive is cured.
U.S. Patent No. 3,877,910 discloses an air cleaner
designed to withstand the impact of an automobile collision.
The cleaner has inner and outer casings. The outer casing
gives upon impact,but the inner casing, formed of stronger
material,resists. The retainer does not form a filter medium
seal.
U.S. Patent 3,399,516 discloses two molded vinyl
gaskets used to form a seal between the filter element and
metal re-taining piece.
U.S. Patent 2,871j976 discloses a filter element
used in an air-cleaner intake silencer. Two end caps,
preferably formed of thermoplastic material, are molded to
the ends of a filter medium. These caps form an air~tight
seal with the filter medium and thus act as gaskets.
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U.S. Patent 2 t 732,031 discloses a sea,l and yasket
combination used in an air'filter. ~ molded piece is heat~
treated and then allowed to cool while in contact with the
paper element. The cooled piece acts as a seal and a gasket.
The prior art gaskets and seals proved generally
adequate in sealing the end of the filter element itself,
However, a second gasket was needed to provide a water seal
between the filter element and the housing into which the
çlement was inserted. That gasket was often fixed to the outer
surface of a metal end retainer used to secure the filter
element in'the housing.
, Means was also needed for facilitating removal
of a used filter element from the housing. Generally, a metal
plate or rim was welded to the metal end retainer for that,
purpose, The plate or rim had-no sealing funation,
The need for ~he three separate pieces, i,e,,
a filter element seal, an element-to-housing water seal, and a
finger grip for removal, resulted in high manuacturing costs
and an unreliable and unwieldy prodùct,
An object of the invention is , -therefore,
to provide an improved seal for a filter elemen-t,
Another object of the invention is to provide
an improved filter element seal capable of performing several
different and distinct ~unctions. Yet another object of the
invention is to provide a filter element seal which eliminates
the need for a separate element-to-housing water seal and a
separate finger grip in a filter assembly.
According to the present invention there is provided a
gasket adapted for use in a filter element having an end
retainer plate, an inner wall defining an axial cavity, an
outer wall concentrically spaced about the inner wall, and a
filter medium positioned betwee~ th,e inner and ~uter walls
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comprislng: an annular seal portion configured to extend
across the open.space between the lnner and outer walls and
sealingly engage ends of the walls and retainer plate r an
annular llp extending outwardly from the seal portion tQ
prevent seepage rom the filter element, and an annular
gripper portion extending inwardly from the seal portion, the
lower surface of the gripper port~on being spaced above the
upper surface of the retainer plate.
. The annular seal portion, the annular lip portion,
and the annular grlpper portions of the gasket may be formed
integrally of semi-flexible urethane.
These and other and further objects and features
of the invention are apparent in the disclosure which includes
the above and below specification and claims and drawings.
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~ BRIEF DESCRIPTION OF T~IE DRAWINGS
. . . _ . _ . .
Figure l is a side elevational view, partly in
section, of a filter elemen~ incorporating the features
of the present invention.
Figure 2 is a sectional detail of a portion of the
~ilter element shown in Figure l.
Fig~xe 3 is a top plan view of the filter element
shown in Figure l.
Figure 4 is a side elevational view, partly in
section, of a filter assembly incorporating the features
of the present invention.
Figure 5 is a sectional detail of a portion of the
filter assembly shown in Figure 4.
DETAILED DESCRIPTION OF THE DRAWINGS
. . _ _
- A filter element embodying the features of the
present invention is indicated generally by the numeral lO.
The filter element l0 has an inner cylindrical wall
12 which defines an axial cavity 14. An outer cylindrical
wall 16 is concentrically spaced about the inner cylindrical
wall 12. Both walls 12 and 16 are provided with openings
which allow the filtrate to pass through the space between
the walls 12 and 16. Preferably, the inner wall 12 is an
expanded metal cylinder and the outer wall 16 is a perforated
metal cylinder.
A filter medium 18 is positioned in the space between
walls 12 and 16. The fllter medium 18 can be any of the
conventional filter materials known in the art. Preferably,
the filter medium l8 is paper.
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The space between the walls 12 a~d 16 is sealed at
both ends of the filter element 10. A conventional plastisol
seal 20 is used at one end. The ledge gasket of the present
invention, indicated generally by the numeral 22, is used at
the opposite end.
The ledge gasket 22 has an annular seal portion 24
which sealingly engages the ends of the walls 12 and 16.
Filter medium 18 adjacen~ to those wall ends is also sealingly
engaged by the seal portion 24. That configuration prevents
unwanted matter from entering the space between the walls 12
and 16.
An annular lip 26 projects outwardly from the seal
portion 24. The space 28 formed between the inner surface
of the lip 26 and outer surface o~ the seal portion 24 is
designed to receive the end of a filter element housing 30.
The relatlonship between the lip 26 and the filter element
housing 30 is best shown in Figure 5. The lip 26 prevents
water and other undesirable elements from seeping into the
space between tke filter element 10 and the filter element
housing 30.
An annular finger grip 32 extends lnwardly ~rom the
seal portion 24. The finger grip 32 has a lower surface 34
which is spaced above the upper surface of a metal end retainer
36. The space 38 between the finger grip 32 and the retainer
36 is large enough to accommodate a finger tip . Wi th this
arrangement, a user can easily remove the filter element 10
from its housing 30 by placing his finger on the lower surface
34 of the finger grip 32 and pulling ~he filter element 10
toward hims elf.
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The ledge gasket 22 is preerably a molded unltary
elt ent. It can be formed of semi-~lexible urethane.
The metal end retainer 36 is a generally circular
plate used to secure the filter element 10 in the filter
element housing 30. The outer edge of the retainer 36 is
embedded in the ledge gasket 22. Preferably, the outer
edge of the retalner 36 has an axial portlon 40 which is
spaced inwardly from the inner wall 12 and which extends
into the ledge gasket 22 and a radial portion 42 which is
spaced axially from the ends of ~he walls 12 and I6 and which
terminates outwardly about midway between the walls 12 and 16.
I~hen in use, the filter element 10 is customarily
seeured within a housing 30. A filter element and housing
assembly incorporating the features of the present invention
is best shown in Figure 4. The housing 30 is a cylindrical
case designed to accommodate the ~ilter element 10, A threaded
spindle 44 mounted in the housing 30 projects through an
opening 46 in the retainer 36 when the filter element 10 is
placed in the housing 30. A wing nut 46 is screwed onto the
spindle 44 to secure the filter element 10. A user can
withdraw the filter element 10 from the housing 30 by removing
the wing nut 46 rom the spindle 44, placing his finger tip
under the lower surface 34 of the inger grip 32, and pul~ing
the filter element 10 toward himsel.
While the invention has been described with reference
to a specific embodiment~ the exact nature and scope of the
invention is defined in the followlng claims.
