Note: Descriptions are shown in the official language in which they were submitted.
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RESEALABLE CONTAINER CLOSVRE
Back~round of the Inve~ion
The present invention relates to a resealable, easy open
can end. More particularly, the present invention relates to a
reaealable closure cap and a cap assembly easily applied to a
spout of a can er-d which is capable of accornmoda-ting inherent
internal can preasures.
The prior art teaches various structures for containers
such as drawn and lroned cans having end panels double seamed to
the can. The end panels typically include opening devices which
are generally called "easy open ends". Examples of easy open ends
of the prior art are described in U.S. Patents 3,929,251;
3,977,341; 3,997,076; 4,024,981; and 4,148,410.
The market for containers having easy open ends may be
extended, particularly, though not exclusively, in the area of
larger volume containera. This may be accomplished through the
utilization oP a cap to close and reseal the spout or pouring
opening defined by the easy open end. Without a resealable
closure cap, the liquid contents of an open container could easily
spill or be other~ise lost. Also, dissociable gases, i.e.,
carbonation, in the remaining liquid are raadily lost Prom
unsealed, open containers.
One construction for a reaealable closure cap assembly
is taught in the p~ior art, namely ~S. ~atent ~,5~0,692. This
reference teachas a construction for auch a resealable closure cap
aasemhly in association with a aelectively contoured can end to
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accommodate the resealable clos~re and to retain the advantacJes
characteristic of the easy open end.
The provislon of commercially acceptable resealable easy
open can end constructions for eurrent and larger volume beverage
containers requires ease of application of the resealing eap over
khe spout, sealable retention of remaining container eontents and
accor~nodation of inherent internal can pressure that builds aftar
resealing the can. Also desired is a ean end eonfiguration having
an easy open end which does not require the use of lever
mechani.sms or the like to aecomplish opening of the pouring
spout. Ideally, the easy open end is easily and readily opened by
a user through the mere applieation of digital pressure in a
simple and safe manner. Sueh eonstruetion of a resea~lable easy
open can end should be aceomplished without diminution of the
convenience and cost effective nature of the basie easy open end
construction during manufacturing, filling, handling, shipping,
distributing, selling and consumer usage.
Experience to date with resealable caps and can end
construetions, such as those diselosed in U.S. Paten~s 4,580,692
and 4,648,528, the contents of which are incorporated here.in by
reference, has indicated a need to as~ure proper application and
retention of the resealable eap over the spout defined by the easy
open end. Despite atternpts and progress in this area o
resealable container closures, there is still a need and a clemand
~or further improvement.
Aecordingly, a new and improved resealable eontainer
elosure is desired which is easily applied to the spout to provide
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an effective seal for an opened container.
~m~ary of the Invention
This inventiorl may be summarized as providing a closure
cap for ~ubstantially gas-tight sealing engagement with a
container closure having an opening therein circumscribed by a
substantially smooth sealing surface thereon. The closure cap
includes a sealing portion releasably engageable in surrounding
gas-tight seaJing relation wi~h the sealing surface on the
container closure. The sealing portion comprises elastic portions
circumferentially spaced by a plurality of radially eY~tending less
elastic portions. The cap assemb]y of this invention may be
anchored to the end wall of a sheet metal container closure.
Among -the advantages of this invention is the provision
of a resealable container closure for a can which is easily and
eEfectively applied over an open spout on a can end.
Another advantage of the present invention is the
provision of a resealable container closure for a can which, when
applied over an open spout, creates and maintains an ef~ective
seal to hold the contents and the in-ternal can pressure.
An objective of this invention is to provide an improved
construction for a resealable container clo~ure for easy open end
beverage containers and the like.
A feature of this inven~ion is the ability to provide an
efEective c:Losiny and sealing mechanism for a can end wh:ich allows
the use oE larger voLume containers because such containers may be
effectively sealed to retain carbonation over longer s-torage
periods required to consume such larger volumes of container
contents.
1hese and other advantages and objectives of the
invention will be more thoroughly understood and appreciated with
reference to the following description and the accompanying
drawings which illustrate, in accordance with the mandate of the
patent statutes, a presently preferred embodiment of a container
closure construction incorporating the principles of this
invention.
~Lief Descri~tion o~ the ~rawings
Figure 1 is a top plan view o~ an easy open can end
construction incorporating the principles of this invention.
Figure 2 is a horizontal section as taken along the line
2-2 in Figure 1.
Figure 3 is an enlarged hoxizontal section as taken
along the line 3-3 in Figure 1.
Figure 4 is a section showing the cap member disposed in
superposed sealing relation on the spout of Figure 2.
Figures 5 and 6 are enlarged sections showing a closure
cap in superposed sealing relation on the spout of Figure 2.
pe~ail.ed Pe~crlp~iQn_~f_~hQ_Invention
As noted above, the present invention is described in
association with a resealable easy open end construction of the
type generally disclosed in U.S. Patents 9,580,692 and 9,698,528
which are incorporated by reference. However, it should be
understood that the present invention may be used in other easy
open can end constructions.
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Where the words "upwardly", "inward", "outwardly",
"under", "underside", "downwardly" and the like are used in this
application, the meaning, unless specifically indicated to the
contrary, is -to be applied with reference to a can standing on its
base in an upright position having a can end incorporating this
invention attached to the top end thereof.
Referriny particularly to the drawing~, Figure 1
illustrates a top plan view of an easy open can end construction
incorporatiny the principles of this invention. Figure 1 shows a
can end closure 12 prior to engagernent of the can end closure at
the top end of a generally cylindrical can body, such as by
conventional double seaming. Such can end closure 12 is generally
made of sheet metal, such as aluminum, steel or tinplate, but may
be made of nonmetallic or laminate material. ThQ closure 12
includes a genexally -flat or planar end wall 16, a countersink
defining an inner panel wall 17, and an outer chuckwall 14
terminating in an upwardly and outwardly projecting annular flange
18 forming a chime for conventional attachment of the sheet metal
can end 12 to a can body by double seaming.
As best shown in Figures 1 and 2, the can end closure 12
further include3 an upwardly projecting dispensing spou-t 20 or
pouring opening. The spout 20 is typically of circular
con~iguration and is ~ormed as an inteyral portion oE the can end
closure. Although the preferred spout 20 i9 circular, it should
be understood that alternate configuration~, includiny oval,
teardrop and ellipsoidal shapes, are comprehended by the present
invention. The spout 20 may inclucle a domed surface haviny a
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score line 26. The score is interrupted by a hinge 28, but
otherwis0 the score line 26 circumscribes and defines an opening
panel 27 which is depressable inwardly of the can upon fracture of
the score line 26. The opening panel 27 and the score line 26 are
surrounded by a continuous lip ~4 having substantially smooth
sealing surfaces 30 and 32. In the preferred embodiments, the lip
24 is circular.
As illustrated in the drawing, the present invention
pertains to a resealing cap 10 which, as described below, is
disposable o~er the lip 24 -to seal the container over the spout
20, or pouring opening. The cap 10 is preferably molded in one
piece of a resinous or plastic material having a relativel~ low
modulus of elasticity, such as, for example, low density
polyethylene, polyvinyl, polyester, polyurethane or nylon. In
addition to a low modulus of elasticity, suitable cap materials
typically exhibit thermal and dimensional stability, chemical
resistance, strength and durability.
The resealing cap 10 includes a sealing portion about
the locking recess 68, adapted to be placed in sealing relation
over the spout 20 and the score line defined opening panel 27
therein. The cap 10 also includes an integral tab 38 projectiny
outwa~dl~ ~rom the cap portion for convenience in dicJi-tally
manipulating the cap 10. In a preferred embodirnent illustrated in
the drawir-g, an integral extendiLIg arm 39 extends from the cap
assembly 10 and terrnina~es in a boss 35. The boss 35 has an
openincJ therethrough to accommodate a rivet 36 for securincJ the
cap assembly 10 to the sheet metal can end closure. ~n example o~
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an alternate lid to which the cap assembly of this invention may
be applied, such as by an integral rivet, is described in U.S.
Patent Application Serial No. 07/302,016, filed January 26, 1989,
and assigned ~o the assignee of this invention.
The outboard edge of a flange of the rivet 36 is formed
downwardly a controlled amount when the rivet 36 i9 staked to
securely attach the cap assembly 10 to the can end closure 12.
The rivet 36 also permits the cap assembly lO to be rotated by
hand about the rivet 36 with relative ease as indicated by dotted
line 90, also called the locus of securement. Preferably the
rivet is an integrally formed portion of a sheet metal end wall
16.
It has been found that a closure cap 10 of this
invention requires sufficient resiliency or flexura to be able ~o
be stretched over the lip 24 of the spout 20 as the cap 10 is
being applied. It is also desirable to maximize the sealability
of a closure cap 10 after it has been applied in order to provide
a structure which does not yield from its sealing enga~Jement when
subjected to internal can pressure situations. These two
objectives of resiliency and sealabililty may appear to be
somewhat contrary to one another, and prior to this invention it
was generally believed that a successful closure cap 10 would be
one having a struct~lre which would strike a very delicate balance
between the fleY~ibility considered necessary to provide resiliency
and the rigidity considered necessary to provide sealability.
The structure of the closure cap assembly 10 of the
present invention provides a device which is able to rnaximize the
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need for flexibility while simul~aneously maximizing the
sealability necessary to withhold high internal can pressures.
This surprising combination o~ seemingly inconsistent and
countervailing properties is accomplished by radially alternating
a plurality of elastic and less elastic portions about the
majority of the circurnference or perimeter of the cap assambly 10
as described in this patent application. Less elastic portions
include those portions which require more stress to cause
deforlrlation as compared to the elastic portions, yet both the
elastic and the less elastic portions have the abili.ty to return
to their original dimensions after the removal of stresses.
In a pre~erred embodiment illustrated in the drawings,
the closurs cap 10 is provided with a series of radially extending
ribs 60. As illustrated in the drawings, the ribs 60 extend
radially outwardly from a location on the cap assembly 10 which is
inwardly of the lip 29 when -the cap assembly 10 is disposed in
overlying sealing relation with the lip 24. The ribs 60 eYtend
outwardly to a location on the cap asseMbly 10 which is at or
beyond the lip 24 when the cap assembly is disposed in overlyiny
sealing relation with the lip 29. In one preferrad embodiment
each rib 60 begins at a location adjacent an outer portion o~ the
boss 50 and extends radially outwardly, with a generally planar,
thin top sur~ace 66, to a radial location coterminous with the
outside diameter o~ the body of -the cap assembly 10, as shown in
Figure 5
The ribs 60 may be provicled at successi.ve locations,
such as every 8 to 10 degrees around at least a ma~ority of the
circumference of the preferred round cap assembly 10. In one
embodiment, the ribs 60 may be successively provided around the
entlre circumference of such cap assembly 10. In Figure 1 the
closure 10 is provided with ribs 60 around about 310 of the
circumference of the cap assembly 10. In a preferred embodiment
the ribs 60 have a circumferential width within the range of from
about .020 to about .030 inch. ~ach rib 60 has a height which
eY.tends above the yenera]. plane of the upper surface 62 of the cap
assembly 10 as defined by the membrane portions 64 between the
al-ternating ribs 60. In a preferred embodimen-t, the upper surface
of the ribs 60 provide locations having a greater height than the
height of the balance of the mernbrane portions 64 of the cap
assembly 10 between the ribs 60. Such rib height, or increased
cap assembly thickness, provide a plurality of portions or zones
about the circumference of the cap assembly 10 which e~hibit less
elasticity than the thinner cap assembly membra~e portions 64, or
~ones, between the ribs 60. It will be appreciated by those
skilled in the art that the height of the ribs 60 may have to be
limited to that height which will not interfere with stable
vertical stacking of the con-tainers.
Although the rib structure is preferred, the present
invention contemplates the use of radially alternating materials
with dissimilar elastic properties about -the circumfererlce of the
cap assembly 10. Likewise, the present invention contemplates -the
use of radially alternating dissimilar materials about the
circumference of the closure cap assembly 10. ~lowever, the use oE
a cap assembly with radially alternating zones of varying
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thickness, or height, is considered the best mode of the present
invention.
The elastic portions 64, or membranes between the radial
ribs 60, preferably have a wall thickness, or height, of less than
about .030 inch, and more preferably from about .015 to .025
inch. In one preferred embodirnent the wall thickness of the
elastic mernbrane 64 tapers from a thickness of about .025 inc}l at
a location inwardly of the lip 24 to a thickness of about .015
inch at a location at or outwardly of the lip 24. Such elastic
membranes 69 provide adequate Elexibility, particularly though not
eY.clusively in the arcuate directions, to permit the cap assembly
10 to fle~ as the cap assembly lO ls digitally applied over the
lip 24 of the pour spout 20 as explained in detail below.
In opera-tion of the cap assembly 10 of the present
invention, the user typically receives a beer or beverage
container with a cap assembly 10 disposed remote from the pour
spout 20. The cap assembly 10, though secured and hinged by a
rivet 36, may be provided with an additional temporary securing
mechanism or device, not shown, to prevent undesired rotational
movement of the cap assembly 10 during handling prior to consumer
us~ . .
In a preferred embodiment, the sealing cap ass~-~mbly lO
is adapted to be pivotally displaced about the rive~. 36 ~rom a
firc;t locatiosl remote from the openinCJ panel 27 and pouring spout
20 to a second location in overlying, sealing relation with the
opening panel 27 and pouring spout 20. When the user intends to
open the container, the cap assembly 10 may be rotated or
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otherwise positioned such that it is disposed directly over the
opening panel 27 prior to the digital initiation of fracture of
the score line 26 defining the spout 20. A clearly visible
pressure point location indicia, such as pressure index 46, may be
provided on the cap assembly at a predetermined location on the
upper surface of the cap assembly 10. Such pressure index 46,
which may be o~ rhomboid character and rnolded on the cap surface,
may cover an included circumferentlal extent of about 70 and
serve to provide maximum visibllity within the limited space
avail~ble. Such pressure poin~ location indicia ~6 is located in
radial alignrnent with and above a selectively shaped and located,
downwardly projecting boss 50 on the undersurface of the closure
cap 10.
The boss 50 is suitably in the nature of a downwardly
projecting extension. As will be apparent, the boss 50 serves to
enhance and magnify unit pressures at the point of digital contact
to initiate fracture of the score line 20 when it is desired to
gain access to an unopened container. Once initiated, the balance
of the fracture of the score line 20 from one end of the hinge 28
to the o-ther end o~ the hinge 28 may he attained with relatively
rninor digital pressure. 'rhe reseal cap assembl.y 10 is typically
pivoted away from the pour spout after the score line 20 has been
fractured. As the score line 20 is fractured, the panel 27 bends
inwardly, about the hinge 28, to result in an unobstructecl pour
spout throuyh which the liquid contents of -the contairler may be
poured.
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After a portion of the co~tents of th~ container have
been removed, it may be desirable to reseal the container. Such
resealing is desirable, for example, to maintain carbonation in a
beverage as well as to preven~ spillage of the contents and to
keep foreign elements from entering the opening of a container.
It will be understood by those c~killed in the art that carbonated
beverages typically release dis~ociable gas/ i.e., carbonation,
unless and until gas equilibriurn is reached and maintained. This
is accomplished in a container by providing an effective gas-tight
seal. The present invention provides a closure cap 10 for
providing substantially gas-tight sealing engagement over the lip
24 of an open pour spout 20.
To reseal the container, the cap assembly 10 as shown in
the drawing is rotationally pivoted directly over the pour spout
20. Then, downward pressure is exerted against the upper surface
o~ the cap assembly 10, preferably at locations near the
circumferential edges of the cap assembly 10. Such pressure
forces a circumferential inwardly ~acing recess 68 in the cap
assembly 10 over the circumferential outwardly facing lip 29
defining the pour spout 20. lt will be appreciated that during
the application of such pressure, the elastic zones or membranes
69 in the closure cap 10 yield as required to permit the cap
temporarily to expand or deforrn slicJhtly, as required, to fit over
the lip 29 around the circumference or perimeter of the pour spout
20. It will be appreciated by those skilled ln the a:rt that the
cap material will deform or flex over the lip 24, well within the
elastic limit of the cap rnaterial. ~fter the elas-tic membrane 64
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has stretched slightly, as downward pressure continues the locking
recess 68 in the cap assembly 10 seats agains~ the outwardly
projecting lip 24 as the fle~ed cap returns through its resilience
to its unflexed shape. The user will have a positive indication,
through sight and through feel, that the cap assembly 10 is
disposed in surrounding gas-tight sealing relation with the
sealing surface 32 on the lip 24 of the pour spout 20 about the
entire circurnference of the lip 24.
The effectiveness of the gas-tigh~ seal between -the
closure cap 1() ar,d the pour spout 20 is dependent on a number oE
variables ~irst, the interference fit between the lip 2~ and the
locking recess 68 is such that the lip 29 has an outside cliameter
ec~ual to or greater than the inside diameter of the locking recess
68~ Preferably, the outside diameter of the lip 24 is from .005
to .010 inch grea~er than the inside diameter of the lockiny
recess 68 to provide a tight fit therebetween. The tight fit in
such embodiment is obtained as the cap 10 attempts to return to
its original dimensions, yet is prevented from accomplishing Eull
return by the interference fit with the lip 24 and thereby retains
a slight degree of stress in the cap 10. Secondly, the sealing
surface 70 of the locking recess 68 intimately contacts at least a
por~ion of the sealing surface 32 of the lip 24, such as for a
raclial contact width of at least .004 inch and preferably at least
.005 inch under the lip 24 and about the circumference oE the pour
spout 20. Also, the contacting surfaces, i.e., the sealing
surface 30 of the lip 24 and the seal.ing surEace 70 of the recess
68, provicle a gas-tight seal at least at one point therebetween
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about the circumference of the pour spou~ 20. This gas-tight seal
may be accomplished by provlding substantially smooth sealing
surfaces 30 and 70 which circumscribe the opening in the sheet
metal container closure 12. Smooth sealing surfaces are those
which enhance a gas-tight seal therebetween by inhibitlng or
restricting yas transfer therebetween. Alternatively, one or more
sealing surfaces may be treated, such as with a blooming agent
that provides a thin film or wax layer which acts to accosnmodate
surface imper~ec-tions at the sealinc3 interface as necessary to
insure a gas-tight seal therebetween.
Once sealed with the closure cap 10, the container is
typically, though not exclusively, stored on its base. During
storage of .such container, gases may become disassociated with the
remaining beverage in the container to cause internal can
pressures on the order of about 30 to about 60 pounds per square
inch or higher to be exertecd against the cap assarnbly 10. When
such internal can pre~sure increases, such pressure may cause the
closure cap 10 to flex somewhat, such as from the position shown
in Figure 5 to a position such as that shown in Figure 6. It will
be appreciated by those skilled in the art that closure cap 10
movement, such as that from Figure 5 to that of Figure 6, may be
more or less dramatic than that illustrated in the drawings. In
particular, the rib 60 and the loop or boss 50 rnay rotate upwardly
more or less than that shown in phantom lines in Figure 6
dependirlg on such variables a5 internal can pr~sure, cap 10
material, and the like.
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Internal can pressure may cause a closure cap 10,
particularly at locations of the ~lexible membrane 6q, to llft
above and away from an upper portion of the pour spout 20.
However, the structure of the cap assembly 10, with the
alternating less elastic portions, or ribs 60, resists flexure
above and away from the pour spout 20. Furthermore, the ribs 60
serve to enhance the seal between adjacent sealing surfaces 30 and
70 in response to such internal pressures. This enhanced seal is
believed to result from an increase in the hoop streng-th of the
pressure lifted cap assembly 10. ~nd, such enhanced seal serves
to anchor the cap assembly 10 firmly in its position about the lip
24 of the pour spout 20.
~ hen it is desired ~o regain access to the contents of
the resealed container, the user lifts the cap assembly 10. The
cap assembly 10 may be lifted such as by grasping an integral tab
38 between the thumb and forefinger and lifting. It has been
found that an inward rolling type motion is desirable to initiate
the separation and release of the cap assembly 10 from its
engagement under the lip 24 of the pour spout 20. The alternating
radial elastic and less elastic structure of the cap assembly 10,
providing circumferentially or perimetrically spaced elastic and
less elastic portions, promotes removal of the cap assernbly 10 in
the same yeneral fashion that facilitates application oE the
closure cap 10. Once the closure cap assernbly 10 has been lifted
from the lip 29, the cap 10 may be pivotally ro-tated about the
rive~ 36, in those applica-~ions in which a rivet 36 is utili~ed,
to provide unobstructed access to the remaining contents of the
can through the open pour spout 20. It will be appreciated that
multiple resealing operatior,s are comprehended with the cap
assembly 10 of this invention as may be necessary or appropriate
over the life of a large volume container with which the cap
assembly 10 may be utilized.
What is believed to be the best mode of the invention
has been described above. It will be apparent to those skilled in
the art that nwnerous variations of the illustrated and described
details may be made without departing from the scope o~ this
invention.
We claim:
