Note: Descriptions are shown in the official language in which they were submitted.
L4
FIELD OF THE INVENTION
This invention relates generally to
container closures and more particularly to
containers having a protruding lip around the
periphery of the mouth.
This application is a division of
application Serial Number 458,908 filed July 13,
1984.
BACKGROUND OF THE INVENTION
.
Containers with snap-fitting, removable
lids often are formed with a mouth defined by a
peripheral lip and a channel which together are
intended to provide a suitable seal with an
associated lid. In most such containers, the lid is
applied to the container at the factory to create a
satisfactory seal. However, the user often removes
the lid with a prying tool, such as a screwdriver,
especially if -the lid is metal, and thi.s action
results i.n deformation of the conLai.ner ancl/or the
lid in a manner
" ~
L7~4
which may disrupt the formation of a cooperative seal when
the lid is later replaced. Such deformation often makes
it difficult or impossible to reseal satisfactorily the
container utilizing the same lid. As a result, the
contents of the container may deteriorate, either
hardening or evaporating. Leakage of the contents from
the container or leakage of water or other liquids into
the container also can occur, either damaging the surface
upon which the container is placed or rendering the
1 contents unusable.
A lid which satisfactorily overcomes many of the
problems attendant to poor resealing is described in my
U.S. Patent 4,279,358. The lid described in that patent
has an inwardly-facing shoulder formed on its depending0
sidewall which engages the underside of the protruding lip
on the container. That lid is particularly suited for use
with certain size and shape container lips, and precise
placement of the inwardly-facing shoulder is desirable for
optimum seating of the lid.
O r l U _ l U~ ~ _ I O U
One aspect of the invention relates to a configuration
for snap-fitting, one-piece, molded plastic lids which are
modifications of the lid described in my U.S. patent
-- 2
~17~
4,279,358. Each lid configuration of this invention is
adapted for use with a container having a laterally
protruding peripheral lip, and is easily and inexpensively
molded, easily removed and ~rovides a tight and secure
seal around the mouth of the container.
The lid includes a top wall and a sidewall which
depends from the periphery of the top wall. The upper
portion of the sidewall comprises a relatively thin,
deformable web segment which is stretchable heightwise.
The lower portion of the sidewall is contiguous with the
upper portion and comprises a skirt having a greater
radial thickness and greater elastic memory than the upper
web portion.
The container preferably is molded and has a specially
contoured rim extending about the container mouth. The
rim includes an outer lip which extends radially outwardly
away from the container sidewall. The outer lip is
smoothly rounaecl along its outer upper sealing surface
~~ having a downwardly and outwardly sloping contour as it
approaches the greatest aiameter of the lip. The contour
of the lip then extends inwardly toward the container
sidewall at a sharper angle. The upper sealing surface o
the lip cooperates with the stretchable web on the lid so
that the web will wrap about the upper sealing surface to
provide a seal.
-- 3 --
-
. ~71t~
In another aspect of the invention the container rim
also may have an inner lip which extends radially inwardly
from the inner surface of the container wall. The inner
lip has a downwardly and inwardly sloping inner seating
surface which cooperates with an inner sealing ring formed
on the lid. In this embodiment of the invention the
container rim is engaged both on the inside and the
outside by the lid and in a manner which enhances the seal
while also providing substantially increased hoop strength
for the container and lid individually and in combination.
In one embodiment of the lid, the inner surface of the
lid sidewall of the container is smooth and free of
interruptions, such as shoulders, along its height. The
inner diameter of the lid sidewall is smaller than the
outside diameter of the container lip and generally equal
to the outside diameter of the container. In another
embodiment of the lid, the sidewall is provided with a
shoulder which, when the lid is seated on the container,
will be disposed below the outer lip of the container to
provided added resistance to inadvertent removal.
In still another embodiment of the invention the lid
may be provided with a compressible ring of sealing
material which is carried by the lid and which will engage
the uppermost edge of the rim when the lid is seated.
In each embodiment of the invention, when the lid is
applied to the container, the inner surface of the
~7171a~
sidewall is advanced over the lip. Once the lower, skirt
portion of the ~idewall has advanced past the lip, its
elastic memory causes it to contract radially inwardly
toward the container sidewall thereby stretching the thin
S u~per web s~gment of the sidewall around the lip of the
container drawing the web into conformity with the shape
of the lip. The contracted lower portion of the sidewall
thereafter remains immediately below the lip, tensioning
the upper web segment of the sidewall in engagement with
10; the lip. The elasticity of the lower skirt portion of the
_
sidewall maintains the seal and prevents the sidewall and
the cover from riding up over the container lip.
The lid may be provided with an inner sealing band or
ring which depends from the top wall and is adapted to
seat against the inner surface of the container opening by
the stretching of the lid sidewall over the container
llp. The sealing band is molded integrally with the lid
and is spaced radially inwardly from the lid sidewall.
The lid also may be provided with a plurality of
,20 reinforcing ribs extending radially inwardly from the
sealing band.
The lid of this invention is reusable, without
destroying its sealing capabilities, for the life of the
elastic memory of the lower portion of the lid sidewall.
In the embodiment of the lid which has no internal
shoulder, the smooth interior surface of the sidewall
` ~717~L4
makes molding of the lid easy and fast and facilitates
application and removal of the lid. In addition, precise
dimensioning Df the container lid to the lip is not
required and greater tolerances are permitted in forming
the lid since the lower portion of the sidewall is
sufficiently flexible to allow it to seat about the lip
even if the fit is not exact. Thus, with the shoulderless
embodiment one lid may be used with a variety of container
lips having different shapes, radial dimensions and formed
of different materials.
In other embodiments of the lid, which utilize a
shoulder on the inner surface of the lid sidewall, the
cooperation between the lid and the container is such that
the shoulder tends to become drawn upwardly into
engagement with the underside of the outer lip of the
container. Although the engagement of the shoulder with
the underside of the lip does not itself provide the
primary seal, it does lessen the chance of the cover
becoming dislodged inadvertently. To that end, this
embodiment of the lid incorporates a V-shaped inner ring
which is spaced radially inwardly from the periphery of
the lid. The outermost wall of the V-ring is spaced
slightly from the stretchable web on the lid sidewall and
cooperates with the web to define an annulus receptive to
the container rim. The configuration of the outer wall of
the V-ring and the web of the sidewall is such as to cause
a pinching or squeezing of the upper rim of the container
tending to bias the lid upwardly. The upward biasing
applied to the lid tends to draw the shoulder of the lid
sidewall into engayement with the underside of the
container outer lip. In addition the V-ring on the lid also
e~hances the hoop ~trength and resistance to distortion of the lid
when it is apart from the container as well as when it is
on the container. Still another advantage of this
embodiment is that the V-ring provides for some
flexibility in the lid which enables the lid to dome and
flex without disrupting the seal between the web and
container lip.
In a modification of the invention the lid may be
provided with a compressible resilient gasket in the
annulus which receives the container rim. The gasket is
located and dimensioned with respect to the lid and rim so
that it is compressed partially by the upper edge of the
rim when the lid is on the container, thereby providing a
supplemental and hermetic seal in addition to the primary
seal effected by the cooperation between the web segment
of ,he sidewall and the container outer lip.
It is among the general objects of the invention to
provide improved containers, lids and cooperative sealing
arrangements therefor. More particularly, it is among the
general objects of the invention to provide containers and
` ~7~71a~
lids of the type described which may be of integral molded
plastic construction yet which display superior sealing
and security characteristics.
Another object of the invention is to provide a
sealing system for a lid and container in which the
integrity of the seal is not destroyed by repeated reuse
of the lid and container.
DESCRIPTION OF THE DRAWINGS
10~ The objects, advantages and features of this invention
will be more olearly appreciated from the following
detailed description taken in conjunction with the
accompanying drawing in which:
FIG. 1 is a pictorial representation of a container
and lid in accordance with the invention;
FIG. 2 is a partial sectional view of the container
lid and container of FIG. 1 prior to application of the
lid;
FIG. 3 is a partial sectional view of the lid and
container of FIG. 2 after application of the lid to the
container;
FIG. 4 shows an alternative embodiment of the
container of FIGS. 1-3;
FIG. 5 shows an alternative embodiment of the
container lip of the container of FIGS. 1-2;
717~
FIG. 6 is a cutaway pictorial representation of one
embodiment of the lid of this invention.
FIG. 7 is a pictorial representation of a container
and lid in accordance with the modified embodiment of the
invention;
FIG. 8 is a partial sectional view of the container
lid and container as shown in FIG. 7 prior to application
or the lid and arranged to illustrate the relative
diameters of the operative lid and container elements;
FIG. ~ is a partial sectional view of the lid and
container of FIG. ~ after application of the lid to the
container;
FIG. 11 is an illustration of the modified form of the
lid incorporating a compressible gasket to effect a
supplemental seal;
FIG. 13 is an illustration of the lid shown in FIG. 11
applied under full pressure to the container; and
FIG. 12 is an illustraticn of the lid and container of
FIG. 11 with the applying pressure relaxed and
illustrating the retention of the supplemental seal.
FIG. 10 is an illustration of the lid shown in FIG 9
applied under full pressure to the container~
1~7~71~
DETAILED DESCRIPTION OF THE PREFERRED EMHODI~ENTS
FIGS. 1-3 illustrate one embodiment of each of an
exemplary container 10 and lid 12 incorporating an aspect
of this invention. Container 10 typically has a generally
cylindrical shape and the upper end of the container 10 is
provided with a mouth 11 which extends generally across
the entire diameter of the container. Mouth 11 is bounded
by a rim 14 region at the upper end of container sidewall
LOj, 16 which may be formed integrally with or formed as a
separate piece and secured to the upper end of sidewall
16. A surface 18 is formed at the rim region 14 on the
inwardly facing side of the sidewall 16 and outer lip 20
is disposed on the outwardly facing side of the rim region
L5 14. Lip 20 projects radially outwardly away from sidewall
16 of the container and extends around the entire
periphery of mouth 11. Lip 20 preferably i5 smoothly
rounded along its entire outer surface and is formed to
define an upper seal surface 21 which slopes downwardly
away from the top of the rim 14 until the point of
greatest radial extent is reached (indicated at 23 in FIG.
2) after which it curves more abruptly inwardly along a
lower seal surface 25 toward sidewall 16. Lip 20 may be
molded with sidewall 16 or formed separately and attached
integrally thereto.
-- 10 --
1~717i4
In each embodiment of the invention the lid 12 is
molded as a unitary piece and includes a top wall 22 and a
~idewall 24 which depends downwardly from the periphery of
top wall 22. Sidewall 24 is formed of two segments, an
j upper web segment 26 adjacent top wall 22 and a lower
segment or skirt 28 spaced from top wall 22. In the
embodiment shown in FIGS. 1-3 the inner diameters of skirt
28 and web segment 26 are substantially equal so that the
inner surface of sidewall 24 is smooth and uninterrupted.
LO ~ The inner diameter of sidewall 24 is generally equal to
outside diameter of container sidewall 16 and is less than
the outside diameter of lip 20. Web segment 26 is
relatively thin and is deformable in a heightwise or axial
direction. Skirt 23 is substantially thicker than web
segment 26, is not deformable in a heightwise direction,
and possesses a much greater elastic memory. Both ~kirt
28 and web segment 26 are expandable in a radial
direction. The lower edge of skirt 28 may be bevelled or
smoothly curved as indicated at 30 to facilitate the
radial expansion of sidewall 24 as it is urged over the
circumferent~al lip 20.
As shown in FIGS. 2 and 3, lid 12 is applied to
container 10 by press-fitting it over rim 14. As the
bevelled or smoothly curved lower edge 30 of lid sidewall
24 is urged downwardly against lip 20 of the container,
the relatively thick skirt 28 is forced radially outwardly
-- 11 --
- ~7~714
to expand as the lid is urged progressively downwardly
onto the container. When skirt 28 has been advanced
beneath lip 20, the elastic memory of the skirt 28 causes
it to snap back to its original configuration and
CQnStrict radially inwardly about the container sidewall
16 until it seats against sidewall 16 beneath lip 20 as
shown in FIG. 3. This elastic constricting force of skirt
28 causes web segment 26 to be stretched heightwise. When
fully seated weh segment 26 is in a thinner stretched
configuration and is tightly and intimately wrapped about
lip 20 causing web segment 26 to conform closely to the
exterior shape of lip 20 to form a continuous seal. The
heightwise stretching of web segment 26 over and around
lip 20 by skirt 28 effectively inhibits lid 12 from rising
upwardly and ofE container 10 and seals mouth 11.
As shown in FIGS. 2 and 3, lid 12 also may be provided
with a sealing ring 32 which is usually molded integrally
with the lid. Sealing ring 32 depends downwardly from the
~ underside of top wall 22, is spaced radially inwardly frorn
the outer perimeter of lid 12, and extends continuously
around the lid parallel with the perimeter thereof.
Sealing ring 32 is dimensioned so that it seats against
surface 18 of container rim 14 when sidewall 24 is urged
downwardly and stretched over lip 20. No channel is
required in rim 14 for proper seating of ring 32, since
the tight fit of sidewall 24 over lip 20 is sufficient to
1~ 71 71~
seat ring 32 against surface 18 and to seal mouth ll.
The lack of ~uch a channel prevents the accumulation of
fluids between ring 32 and surface 18 which can prevent
the formation of a good seal and permits all fluids to
j drip back into the container.
In a modific~tion of the foregoing embodiment shown in
Fig. 6, lid 12 may be provided with a plurality of
radially extending ribs 39 on the underside of top wall
22. Ribs 39 typically extend from sealing ring 32
lO; inwardly to another ring 37 radially spaced from ring 32
and concentric therewith. Ribs 39 are equally spaced in a
circumferential direction about rings 32 and 37 and
preferably decrease gradually in thickness normal to top
wall 22 moving from ring 32 to ring 37. Thus, the lower
radially extending surface of each rib 39 rises upward
toward top wall 22 going from ring 32 to ring 37 to
provide each rib with a trapezoidal cross-sectional
shape. Ribs 39 reinforce top wall 22 and prevent top wall
~ 22 from being deformed radially inwardly or outwardly and
they help preserve the seal between lid 12 and mouth ll.
Ring 32 also prevents radial deformation of lid 12, thus
providing a more secure seal, especially in impact
situations, by maintaining the circular shape of lid 12.
Ribs 39 maintain the flat configuration of top wall 22 and
prevent it from warping, thus minimizing splaying of
sidewall 24 an~ providing a secure seal. Ribs 39 and
. ~ 7~ 7~
rings 32 and 37 are formed of the same material as the lid
and add little extra weight thereto.
Alternative embodiments of the container and lid
configurations are shown in FIGS. 4 and 5. Since the
containers and lids illustrated in FIGS. 4 and 5 are
identical in some general respects to those of FIGS. 1-3,
like numbers are used for like parts for convenience. In
FIG~ 4, exterior sidewall 16 of container 10 is provided
with an indentation 50 formed immediately below lip 20.
In this embodiment the inner diameter of skirt 28 is
slightly less than that of the outside diameter of
container sidewall 16, so that as skirt 28 is forced over
lip 2G, its elastic memory causes skirt 28 to retract
sufficiently to reside within indentation 50. Indentation
50 conforms to the shape of the inner wall of skirt 28 in
its seated condition, so that skirt 28 seats securely and
tightly within indentation 50. This seating of skirt 28
within indentation 50 produces a greater heightwise
~- stretching of web segment 26, thereby providing a tighter
fit of lid 12 on container 10 and providing a more secure
seal.
FIG. 5 illustrates the application of this invention
to a container having a lip 52 similar in shape and
dimension to that found on conventional metal, wide-mouth
paint containers. Lip 52 is provided with a less rounded,
more sharply angled, top and undersurface than lip 20 and
- 14 -
~717~.4
is also provided with a lesser radial dimension with
respect to the container sidewall. Typically, the radial
dimension of lip 52 measured in its protrusion from
container sidewall 16 is about one-half as great as that
of the type of lip illustrated at 20 in FIGS. 1-4,
The lid and container of this invention have several
advantages over the lid and container as described in U.S.
patent 4,279,358. As to the lid, omission of the inwardly
facing shoulder on the inner surface of sidewall 24,
enables the foregoing embodiment of the lid to be molded
more easily, faster and less expensively. As to the
containerg lip 20 has a much greater radial dimension
which provides a much larger and better shaped surface
over which web segment 26 may contact the lip 20. That
causes a greater stretching force of web segment 26 with
resulting greater surface area of the sidewall which wraps
about the lip 20. The more rounded configuration of lip
20 allows web segment 26 to conform more closely to the
~- shape of the lip. The rounded configuration of lip 20
also facilitates both the removal and the application of
lid 12 to container 10. The greater extent of wrap of web
segment 26 around lip 20 and the greater radial dimension
of lip 20 also ensures that the lid will not inadvertently
. pop off the container. The greater chord length and
greater stretching of web segment 26 allows the container
to accommodate variations in web segment 26 or improper
~ ~7~
seating of ring 32 against surface 18 without breaking the
seal between the container and the lid.
The absence of an inwardly facing shoulder facilitates
application and removal of the lid from the container.
The degree of curvature which may be imparted to the lip
is in part a function of the degree of flexibility and
elasticity of the material used for the lid. The softer
or more flexible the lid material, the more it will bend
and the sharper the curve formed by the lip may be and the
10~ greater its permissible radial extent. A stiffer material
~~ will require a more gentle slope or curve on the underside
of the lip than a lip with a lesser radial extent.
The amount of stretch that may be imp~rted to the web
segment and the amount of snap the skirt possesses as it
is pushed over the lip during application of the lid is a
function of the elastic memory of the skirt which in turn
is proportional to the skirt thickness. It also is a
function of the strength of the skirt relative to the web
~- segment. If a greater elastic memory or a greater
strength or a tighter seal is desired the skirt may be
provided with a greater radial thickness. The seal may be
improved further by providing the skirt with an inside
diameter a few thousandths of an inch less than the
outside diameter of sidewalls 16 of the container. In
this manner, the skirt will snap back against the
container sidewall more quickly and bear against the
- 16 -
~27~71~
container sidewall with greater force, providing a tighter
seal by more tightly stretching the web segment over the
lip.
By way of example only, the dimensions of a container
; and lid described in the foregoing embodiments of this
invention are set forth. It is to be understood, that by
providing such examples, the scope of the invention is in
no way limited. Thus, top wall 22 of lid 12 may have a
thickness of 0.05 inches; lip 20 extends radially
outwardly a maximum distance of 0.145 inches from the
~.
inside wall of container 10; the radius of curvature of
lip 20 at its maximum radial extent is .05 inches; lip 20
has an axial extent of about .25 inches; web segment 26
has a radial thickness of 0.~15 inches; skirt 28 has a
radial thickness o~ 0.06 inches or about one half the
thickness of lip 20, and extends outwardly a distance of
0.045 inches from the exterior surface of web segment 26;
skirt 28 has a heightwise dimension of approximately 0.125
.i
inches; the entire heightwise dimension of the sidewall 24
is approximately 0.265 inches; and the heightwise
dimension of web segment 26 alone is 0.14 inches.
Typically, the lid of this invention is formed of a
low density polyethylene, although other suitably elastic
materials may be used.
Container 10, although shown as being cylindrical, may
be a cube, a parallelopiped or any other desired shape.
- 17 -
i.~7~714
Mouth 11 may be formed as shown or formed on an axially
extending neck with a cross-sectional dimension less than
that of container 10.
FIGS. 7-13 illustrate additional embodiments and
; modifications of lids and containers in accordance with
the present invention. In the embodiment of the container
shown in FIGS. 7-9 the rim region 14 of the container
includes an inner lip 60 in addition to the outer lip 62.
The inner lip projects radially inwardly from the
container sidewall 64. The inner lip 60 has a downwardly
~- and inwardly sloping surface 66 which serves as an inner
seat in cooperation with a V-ring formed on the lid, as
will be described. The lower region of the inner lip 60
may slope downwardly and outwardly, as indicated at 68, to
merge smoothly with the inner surface of the container
wall 64. The inner lip may extend downwardly along the
container wall to a greater extent than does the outer lip
62. The inner lip 60 serves to add substantial hoop
,
`~ strength to the container, particularly when the container
is held by a bail. Preferably the thickness of the rim is
at least substantially equal to or greater than the
thickness of the container sidewall. It also cooperates
with the shape of the outer lip and the configuration of
the lid in a manner which facilitatés placement of the lid
on the container.
- 18 -
~7~7~
.. . .. .. . , . .. . . . . . . . . . . .. . . .. ...... . . . ~ .. ... . . .. . . . .
The outer lip 62 has the upper seal surface 70 which,
as shown, extends in a smooth curve from the upper edge 72
of the rim downwardly and radially outwardly. In the
embodiment shown in FIGS. 7-9 the outer lip 62 ~erminates
; in a relatively flat, downwardly facing horizontal ledge
74.
The lid illustrated in FIGS. 7-9 is of molded plastic
construction and includes a top wall 76 and a surrounding
sidewall 78 which extends downwardly from the top wall.
As with the previously described embodiment, sidewall 78
includes two segments, an upper web segment 8D and a lower
skirt segment 82. The skirt segment 82 is considerably
thicker than the web segment 80 and has a greater elastic
memory. The relatively thinner web segment 80 is more
easily stretched and can be wrapped about the outer lip 62
of the contalnerO
The embodiment of the lid shown in FIGS. 7-9 has a
~ shoulder 84 formed at the inwardly facing surface of the
sidewall 78. As shown, the shoulder 84 may define the
transition between the web segment 80 and skirt segment
82. The shoulder 84 should be located along the sidewall
78 so that when the lid is pressed onto the container the
shoulder 84 can be advanced downwardly about the outer lip
62 to a location below the underside of the outer lip, as
defined by ledge 74. As will be described in further
-- 19 --
ii4
detail the shoulder 84 coo~erates with the underside 74 of
the outer lip 62 to provide an interlock and assure that
the lid will not be dislodged inadvertently except when
its removal is specifically intendedO As described in
connection with the previous embodiments the relative
diameters of the outer lip 62 and web section 80 of the
lid sidewall are such that when the web segment 80 is
disposed about the outer lip 62 it will wrap about the
outer lip in somewhat of a stretched configuration. Thus,
the inner diameter of the web segment 80 is smaller than
~~- the outer diameter of the outer lip 62. Additionally the
inner diameter defined by the skirt segment 82 of ~he lid
is no greater than the outer diameter of the container
sidewall and ~referably may be slightly smaller to provide
an enhanced constricting effect.
The lid also includes annular Y-ring 86 which is
formed integrally with top wall 76 of the lid and is
located radially inwardly of Lhe sidewall 78. The V-ring
~ 86 includes an inner wall 88 which slopes downwardly and
radially outwardly, and an outer wall 90 which slopes
upwardly and outwardly. The V-ring outer wall 90
generally conforms to the slope of the inner seat 66 on
the inner lip 60. The inner and outer walls 88, 90 are
joined at a transition region 92 defined at a bight
between the walls 88, 90. The upper end of the outer wall
90 merges into an annular connecting wall 94~ A~ shown in
- 20 -
1~ 7~ 7~
FIG. 8 the sidewall 78 extends from the outer extremity of
the connecting wall 94. Thus, the outer wall 90 of the
V-ring 86, the connecting wall 94 and sidewall 78 define
an annular channel 96 which is receptive to the rim of the
container as illustrated in FIGS. 9 and 10 and as will be
described. The annular channel ~6 is generally tapered
~rom a wider region at it5 lower end to a more narrow
region at its upper end, at the connecting wall 94. The
lower region of channel 96 defines a channel entry annulus
indicated at the arrow 98 which defines the region through
which the container lip enters into the channel 96. The
entry annulus 98 extends between the outer surface of
V-ring outer wall 90 and the closest point on the interior
of the sidewall 78 which, as shown, is the inner surface
of the shoulder region. In the preferred embodiment the
entry annulus 98 is smaller than the corresponding
radially measured thickness of the lipped container rim.
When the lid is fitted onto the container the sidewall 78,
including its web and skirt segments 80, 82, as well as
the V-ring outer wall 90 flex so as to receive the lipped
rim of the container. The lid components flex so as to
enlarge the channel entry annulus 98. In this regard it
should be noted that the generally upwardly tapering
cross-sectional shape of the container rim, as defined by
the inner lip 60 and/or outer lip 62 forms a generally
wedge shape which facilitates progressive englargement of
- 21 -
171:4
the channel entry annulus 98 and smoothly and temporarily
distorting the V-ring outer wall 90 and sidewall 78.
~IG. 9 illustrates the lid and container of FIG. 8 in
a seated, interlocked and sealed configuration. As
; illustrated, the web segment ~D has a significant portion
which wraps about the outer lip in snug conformity and
contact with a significant portion of the upper sealing
surface 70. FIG. 9 illustrates the region of snug
wrapping contact along a band indicated generally by the
L0 region lO0. As described previously in connection with
other embodiments of the invention, the constricting force
of the skirt segment 82 secures the skirt 82 about the
container sidewall, below the outer lip 62 to maintain the
web segment 80 in its wrapped, sealed relation about the
outer lip 62.
It should be noted that a high degree of effective
sealing may be obtained without requiring full wrapping
contact of the web segment about the full outer surface of
the outer lip 62. By providing a band along which the
seal is made, substantially greater seal surface contact
is made than is the case with most containers which, at
best, provide little more than a sealing line rather than
a distinct band.
Among the further advantages of the invention is that
the lid and container lip may be molded with a relatively
wide range of tolerances without adversely affecting the
- 22 -
P~71714
quality and effectiveness of the seal. Thus, as can be
seen from FIGS. 9 and 10 the annular channel 96 may be
dimensioned to have a vertical height ~omewhat greater
than the vertical height of the outer lip 62. When the
lid is on the container, as shown in FIG. 9, the
connecting wall 94 may be spaced somewhat from the upper
edge 72 of the rim thereby leaving the uppermost region of
annular channel 96 unoccupied. The additional unoccupied
region of annular channel 96 provides for a certain amount
of tolerance between the lid and container. When the lid
is fitted onto the container the skirt and web segments
will assume the configuration illustrated in FIG. 9 thus
effecting the seal. By providing the additional vertical
height to the annular channel 96 the precise location of
the shoulder is less critical. This may be seen from FIG.
10 which illustrates the container and lid of FIG. 9 but
with the lid pressed down more forcefully over the
container rim. Although, as shown in FIG. 10, that causes
the shoulder to separate somewhat from the bottom of the
outer lip 62, the sealing band 100 still is maintained.
Thus, the skirt continues to maintain its constricting
effect which continues to cause the wrapped sealed
configuration of the weh about the outer lip. Thus, the
foregoing configuration assures that an effective seal
will be made and will not be disrupted even if the lid and
container are subjected to rough handling.
- 23 -
-
~ 7~ 7 1~
It may be noted from FIG. lO that the sealing band lO0
has shifted somewhat from its relative location
illustrated in FIG. 9. That results from a tendency of
web segment 8~ and V-ring outer wall 92 to be further
wedged apart by the generally wedged shape of the
container rim. In this regard it should be noted that the
taper of the annular channel 96 preferably is somewhat
less than the general wedge or taper defined by the rim of
the container. As the parts are progressively mated the
generally wider wedge defined by the rim will tend to
spread apart the relatively narrower wedge defined by the
annular channel 96. This has been found to tend to cause
the sealing band lO0 to shift positions more upwardly
along the upper sealing surface 70. The seal is not
disrupted or broken but, instead, is merely shifted
thereby enabling the container and lid to be subjected to
varying loads and a wide variety of conditions which,
instead of brea}cing a seal, merely shift it to a different
but continuous location.
It also should be noted that the relative sizes of the
wedge on the container rim and the wedge defined by the
annular channel also are such as to cause the lid and
container to tend to assume the configuration shown in
FIG. 9. Thus, even if the lid is forced down to the
position shown in FIG. lO, when released the V-ring outer
wall 90 will tend to re-expand somewhat and in cooperation
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with the web segment 80, will tend to pinch the wedge like
rim to tend to cause the lid to rise upwardly. That, in
tu~n, tends to draw the lid to the configuration shown in
FIG. 9 in which the shoulder is in proximity to or engaged
i with the ledge 74 thereby preventing further rise of the
lid.
The V-ring, and particularly its outer wall 90,
maintains contact with the inner seat 66 of the inner lip
60. Although that does provide an additional sealing
L0 region, the ~rimary seal of the invention is effected
along the band contact between the web segment and the
outer lip. The cooperation between V-ring outer wall 90
and inner seat 66, however, serves to substantially
increa-e the hoop strength of the combined container and
lid. That is a particularly important advantage when the
container is used ~n environments where rough handling may
be expected, such as with paint cans.
FIGS. 11-13 illustrate another modification to the
~ invention in which a supplemental seal is included. In
this embodiment a resilient compressible gasket 102 is
located along the upper region of the annular channel 96.
The gasket 102 may be formed from a foarn plastic material
which may be in the form of a foam plastic O-ring or which
may be extruded directly into the upper region of the
annular channel 96. The gasket 102, annular channel 96
and contdiner rim are of a configuration such that when
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~ 714
the lid is in its normal secured position on the
container, such as the configuration shown in FIG. 9 and
illustr~ted again in FIG. 12 the gasket 102 will be
partially compressed against the upper edge 72 of the
rim. As shown in FIG. 13 the gasket also should be
compressible even further such as when the lid is forced
down fully over the container, as described above in
connection with FIG. lO.
Thus, I have defined my invention and its various
aspects and embodiments It ~hould be understood,
hswever, that the foregoing descriptions of the invention
are intended merely to be illustrative thereof and that
other embodiments and modifications may be apparent to
those skilled in the art without departing from its spirit.
Having thus described the invention what I desire to
claim and secure by letters ~atent is:
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