U.S. patent number 3,690,499 [Application Number 05/167,151] was granted by the patent office on 1972-09-12 for composite closure.
This patent grant is currently assigned to Continental Can Company, Inc.. Invention is credited to Arthur L. Lawson, Peter A. Vercillo, James E. Westfall.
United States Patent |
3,690,499 |
Westfall , et al. |
September 12, 1972 |
COMPOSITE CLOSURE
Abstract
The disclosure relates to improvements in closures comprising a
dependent skirt which encircles a container neck, and which include
a pull tab attached to the skirt for removal of the closure.
Preferred embodiments disclosed relate to a composite closure
consisting of a flexible, resilient plastic fitment, and a gasketed
rigid closure panel. The fitment has a perforate top and dependent
skirt. The closure panel is retained within the skirt. A lifting
ring in the top of the flexible plastic fitment is joined to
marginal portions of the fitment top by breakable bridging portions
and by a substantially unbreakable integral hinge portion attached
directly to a portion of the skirt. Once breakable bridging
portions are broken, the semi-detached ring serves to alert
shoppers that the closure has been previously tampered with or
removed. The exterior face of a downwardly extending skirt of the
plastic fitment is substantially straight, and the interior face
includes detent means for engaging the neck of the container. The
closure includes means, responsive to the lifting of the ring, for
breaking a vacuum within the container before the detent means
begins to clear cooperating elements on the neck. In a preferred
embodiment, the closure also includes special positioning of the
detent means so that no detent means are positioned on either side
of the plastic fitment at a quarter circle from the hinge.
Inventors: |
Westfall; James E. (Western
Springs, IL), Lawson; Arthur L. (Deerfield, IL),
Vercillo; Peter A. (Oak Park, IL) |
Assignee: |
Continental Can Company, Inc.
(New York, NY)
|
Family
ID: |
22606149 |
Appl.
No.: |
05/167,151 |
Filed: |
July 29, 1971 |
Current U.S.
Class: |
215/253; 215/274;
215/262 |
Current CPC
Class: |
B65D
51/1677 (20130101); B65D 51/145 (20130101) |
Current International
Class: |
B65D
51/14 (20060101); B65D 51/00 (20060101); B65D
51/16 (20060101); B65g 067/02 () |
Field of
Search: |
;215/40,46R,46A |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: King; Lloyd L.
Assistant Examiner: Grant; Edwin D.
Claims
We claim:
1. A press-on, pull-off closure for maintaining a vacuum in a
container whereby the closure and container provide a package which
is readily opened by a consumer without the use of tools, said
closure having a generally cylindrical depending skirt portion
which is adapted to extend down around a neck of said container,
said skirt including first detent means for releasably securing
said closure to said neck, said skirt having attached thereto a
lift element comprising a tab means and a hinge attaching said tab
means to said skirt, said lift element being adapted for lifting of
same by said consumer, for lifting said closure from said
container, which closure includes vacuum release means responsive
to said lifting of said lift element for breaking said vacuum
within the container prior to substantial release of said first
detent means from said neck.
2. The closure of claim 1 which comprises a flexible, resilient
plastic fitment and a rigid, disc-shaped gasketed closure panel,
wherein said fitment has a perforate end panel with said skirt
depended therefrom, wherein said perforate end panel includes said
lift means, wherein said tab means is releasably attached to other
portions of said end panel by at least one readily frangible
bridge, and wherein said closure panel is retained within said
skirt adjacent said end panel by second detent means extending
radially inwardly from said skirt.
3. The closure of claim 2 wherein said closure panel is shaped to
include a shallow, upwardly opening, concentric depression, and
wherein said fitment includes a pair of slightly elevated
concentric beads respectively adjacent the radially outward and
radially inward extreme of said depression, wherein said depression
and said beads are cooperatively disposed as a composite stacking
ring.
4. A package comprising in combination a container, and a composite
closure; said container including enlarged product-enclosing
portion, a shoulder portion, and a neck portion, the neck portion
having a top seal finish, and having a continuous outwardly
extending neck bead around the entire circumference thereof; said
composite closure including a substantially disc-shaped rigid
closure panel member, and a flexible outer neck-engaging fitment,
said relatively rigid closure member having means for forming a
compression seal adjacent to the periphery thereof by which said
closure member sealingly engages said top seal finish of said neck,
said rigid closure member having an outer periphery extending
radially outwardly of said compression seal, said flexible outer
fitment including a perforate end panel and a skirt depending from
said end panel, said skirt having pull tab means attached at one
axial end thereof by a flexible hinge, said dependent skirt
including an inwardly directed fitment-retaining first bead means
for engaging said neck bead and for retaining said fitment on said
neck, said dependent skirt also including closure panel retaining
second bead means between said first bead means and said perforate
end panel, said second bead means being in the form of a plurality
of second lugs intermittently disposed around said neck, one of
said second lugs being a hinge-lug positioned concentrically with
said hinge, said first bead means being in the form of a plurality
of first lugs, wherein respective first lugs are positioned spaced
apart from said hinge-lug a sufficient distance whereby the skirt,
in response to axially directed forces transmitted through said
hinge, can flex upwardly a sufficient distance to move said
hinge-lug against an opposing portion of said outer periphery and
lift a portion of closure panel member from said top seal finish to
break the seal before the first bead means is moved axially
upwardly over said neck bead.
5. A package comprising in combination a container, and a composite
closure member; said container including an enlarged
product-enclosing portion, a shoulder portion, and a neck portion,
the neck portion having a rounded end finish thereof, and having a
continuous outwardly extending neck bead around the entire
circumference thereof; said composite closure member having a
substantially disc-shaped rigid closure panel member and a flexible
outer neck-engaging fitment, the relatively rigid closure member
having means for forming a compression seal adjacent the periphery
thereof by which said closure member sealingly engages the end of
said neck, said rigid closure member having an extended peripheral
portion which extends radially outwardly of said compression seal;
said closure panel member having a perforation passing therethrough
radially inwardly of said compression seal; said flexible fitment
including a perforate flexible end panel and a skirt dependent
therefrom, said end panel comprising a lift element including a tab
means and a hinge attaching said tab means to said skirt, said
composite closure including means for hermetically sealing a
portion of said lift element to said closure panel member in a zone
surrounding said perforation for hermetically sealing the
perforation, said fitment including at least one frangible bridge
means for releasably connecting said tab means to a portion of said
perforate end panel.
6. A press-on, pull-off closure for containers having a neck and
continuous circumferential bead means extending radially outwardly
from said neck, said closure comprising a flexible cap having a
depending skirt portion which is adapted to extend down around said
neck of said container, said cap having tab means attached to said
skirt portion by a hinge, which skirt portion includes detent means
for engaging said continuous circumferential bead means, and
wherein said skirt portion is free of said detent means at both
sides of said skirt portion with respect to a center line drawn
through the hinge.
Description
This invention relates to container packages in general, and in a
preferred embodiment, it is directed to a dual-purpose tamper-proof
composite closure for use on a container to form a package. This
preferred composite closure consists of an outer flexible plastic
fitment and an inner rigid closure panel. This invention may be
considered an advance with respect to the composite closure
disclosed in U.S. Pat. No. 3,460,701.
The rigid closure panel of this invention may be formed from metal,
and unlike the composite closure disclosed in the previously cited
patent, the closure panel need have no appreciable skirt dependent
therefrom.
It has been observed in the course of the utilization of the
composite closure heretofore disclosed in U.S. Pat. No. 3,460,701
that the force required to remove the closure must be great enough
to release the detent means by which fitment is retained on the
neck of the container, and simultaneously break the vacuum by
lifting of the inner rigid closure panel from the neck. One
approach to making closure removal easier is disclosed in copending
patent application Ser. No. 31,650 filed Apr. 24, 1970 by
Powalowski and Westfall, said application being owned by a common
assignee with the present application. This approach involves
providing means for sequentially releasing said detent means and
breaking said vacuum by automatically releasing the detents before
breaking the vacuum. In the previously filed application, a
composite closure is disclosed in which the axially directed forces
exerted through the pull tab initially begin the release of the
fitment-retaining detent means, and subsequently transmit the
axially directed forces to the rigid inner closure member to break
the vacuum seal.
Another problem which has been discovered to be inherent in the
operation of such two-piece, pull tab closures in which generally
axially directed pull-off forces are transmitted to a
neck-encircling dependent skirt, is the tendency for the skirt to
bow radially inwardly at both sides of the skirt about a quarter
circle in either direction from the base of the tab, thus making
continued separation difficult, once separation is started.
It is an object of this invention to provide improvements whereby
composite closures of this general type are more easily and
conveniently removed when desired.
It is a general object of the composite closures improved by the
present invention to provide a package which, though reclosable,
provides an automatic tamper-warning when the inner seal is first
opened. It is an object to provide the art with a composite closure
which is extremely difficult, if not impossible, to remove by any
means which avoid giving the tamper-warning. It is a further object
of this invention to provide a composite closure having a
tamper-warning, lifting or removable ring thereon, which ring also
serves to permit normal removal of the closure without the aid of
tools or the like. It is another object of this invention to
provide a new and improved composite closure which is inexpensively
manufactured, easily assembled and applied. It is another object to
provide such a closure which includes a stacking ring which not
only functions as a shock absorbing means to prevent loss of the
seal should the package be subjected to accidental impact, but
which moreover assists, to a very high degree, in the stabilization
of an article stacked on a like article. It is an important object
of this invention to provide means responsive to the lifting of the
removal ring for breaking a vacuum seal within the container prior
to disengagement of cooperating detent elements which retain the
closure on the neck of the container. It is another important
object of this invention to provide improved cooperating detent
means which greatly facilitate continued separation of the closure
from the neck of the container once the separation of the fitment
from neck detents has been initiated.
Other objects of this invention will become apparent upon
consideration of the following description and the accompanying
drawings wherein like reference characters refer to like parts.
The invention is described in general, and in particular in
connection with several preferred embodiments hereinafter with the
aid of the drawings:
FIG. 1 is a plan view of a composite closure in accordance with
this invention;
FIG. 2 is an enlarged fragmentary cross-sectional view taken
approximately along the line 2--2 of FIG. 1;
FIG. 3 is a cross-sectional view taken approximately along the line
3--3 of FIG. 1;
FIG. 4 is a fragmentary perspective view illustrating the operation
of the closure of this invention;
FIG. 5 is an enlarged cross-sectional view similar to that of FIG.
2 showing the relative position of elements shortly after the
vacuum has broken;
FIG. 6 is a perspective view of an alternative construction of the
metal closure panel;
FIG. 7 is a perspective view of the composite closure utilizing the
panel illustrated in FIG. 6;
FIG. 8 is an enlarged fragmentary perspective, partially sectioned
view of the alternative embodiment of FIGS. 6 and 7; and
FIG. 9 is a bottom view of a preferred fitment.
A first preferred embodiment is described hereinafter in connection
with FIGS. 1 through 5, and a second preferred embodiment is
described with the aid of FIGS. 6 through 8. FIG. 9 is provided to
illustrate highly advantageous off-set positioning of upper and
lower detent lugs around the circumference of the closure which can
be used with either of the foregoing embodiments.
In accordance with this invention, a package generally indicated at
20, comprises a glass container generally indicated at 22 and a
composite closure generally indicated at 24.
In the illustrated embodiment, container 22 includes a relatively
large product-enclosing portion 26, a shoulder portion 28 and a
relatively short cylindrical neck 30 providing mouth 32 through
which access to the contents of the product-enclosing portion 26
can be gained. Neck 30 has a top seal finish 34 which provides a
seat for the sealing means which will be described hereinafter. The
outer surface 36 of neck 30 includes relatively long side finish
38, inwardly necking surface 40, and relatively narrow diameter
neck portion 42. Flange 43 extends radially outwardly from the
entire circumference of narrow portion 42. In the illustrated
embodiment, surface 40 converges downwardly and inwardly and this
configuration is a preferred configuration. However, surface 40 may
alternatively extend substantially perpendicularly from narrow
portion 42.
Composite closure 24 includes outer flexible, resilient plastic
fitment generally indicated at 44, and relatively rigid closure
panel 46 which includes bonded sealing gasket 48.
Rigid closure panel 46 has the general configuration of a
relatively flat disc but includes downwardly extending peripheral
portion 49 which encircles end 34 and a small portion of side
finish 38 on neck 30. It will be appreciated from a consideration
of the enlarged cross-sectional view (e.g., FIG. 2) that closure
panel 46 is shaped at its periphery, and in the region immediately
adjacent to its downwardly extending peripheral portion 49, to
provide a downwardly opening concave gasket channel 50, and
upwardly opening concave portion 52 adjacent, and immediately
inwardly of channel 50, and central, generally flat portion 54.
Flexible gasket 48 is preferably permanently bonded to closure
member 46 within downwardly opening concave channel 50 thereof. It
will be appreciated from the enlarged cross-sectional view that,
when a container in accordance with this invention is assembled,
gasket channel 50 mates with end finish 34, and the lower surface
of gasket 48 takes on the shape of end finish 34 to provide a
reliable hermetic seal. Thus, rigid closure panel 46 has the
general appearance, as indicated hereinbefore, of a generally flat
disc, and gasket 48 lines the recess of concave portion 50. When
the container 20 is vacuum sealed, atmospheric pressure on rigid
panel 46 urges gasket 48 even more firmly against end finish
34.
It will be appreciated from the description following, that when
like containers 24 are stacked on top of one another, panel 46
provides a seating function. Structures in flexible fitment 44
provide the full mechanical equivalent of stacking rings. However,
depending on the particular configuration of the bottom of bottle
22, upwardly opening concave portion 52 of panel 46 may function in
part as an annular stacking groove.
Plastic fitment 44 includes substantially cylindrical skirt portion
56 depending from a top panel, generally indicated at 57. Panel 57
comprises inwardly extending fragmentary planar flange portion 58,
and lifting ring 60 which are joined by a plurality of readily
breakable bridging portions 62, 62. It will be appreciated from a
consideration of FIG. 1 that the only direct connection in the
horizontal plane, i.e., the plane of panel 57, between lifting ring
60 and flange 58, are bridging portions 62, 62, and that lifting
ring 50 is also directly connected to dependent skirt 56 by
relatively wide band 64. Band 64 is an integral hinge due to the
flexible character of fitment 44.
Skirt 56 includes a smooth outer face 66 and, in cross section, as
seen in FIGS. 2 and 3, has a relatively thin portion 68, and a
thickened end portion or collar bead 70. Dependent skirt 56 also
includes a number of co-planar upper bead means, or lugs 72
extending radially inwardly from wall 68, and a plurality of
co-planar lower bead means, or lugs 74 which also extend radially
inwardly from wall 68.
As used herein, the terms "upper," and "lower," refer to the
relative position of elements when the container is in its
assembled condition and is standing upright.
Thus, only the inner surface 75 of fitment collar 56 is shaped for
mating with structures on container neck 30, and with downwardly
extending peripheral portion 49 of rigid closure panel 46. Upper
lugs 72 are positioned on wall 68 to engage peripheral portion 49
of closure panel 46 and to secure closure panel 46 adjacent end
panel 57. Lower lugs 74 are positioned to engage radially outwardly
extending flange 43 of neck 30 and thus secure fitment 44 to neck
30. The relative position of lugs 72, 74 around the circle of
fitment 44 is an important part of the present invention, and the
relative positioning will be discussed more fully hereinafter with
the aid of FIG. 9.
Lifting ring 60 includes relatively flat, thin portion 77 and
thickened central bead-like portion 78. Fitment top panel 57 also
includes upwardly extending bead or boss 79 at its periphery. It
will be appreciated from the following description that thickened
central portion 78 not only serves to structurally reinforce
lifting ring 60, but moreover serves to prevent cutting of fingers
when pulling ring.
Composite closure 24 is assembled by inserting rigid panel 46 into
plastic fitment 44 and snapping it in place above detent lugs 72.
Thereafter it is extremely difficult to separate these members, and
rigid panel 46 remains with fitment 44 whenever closure 24 is
removed. Package 20 is assembled by snapping closure 24 in place on
neck 30, whereby lower detent lugs 74 engage bead 43. It will be
appreciated that a lug 74 is shown in cross section in FIG. 8,
whereas in FIG. 2 and FIG. 5, only a tapered end portion of lugs
74, and 82 respectively, are visible in perspective in the
background. In FIGS. 2 and 5 most of lugs 74, and 82, respectively
are obscured from view by neck 30. This positioning is further
explained with the aid of FIG. 9.
Referring now to FIG. 9, it will be appreciated that the respective
and relative angular positions of hinge 64, upper lugs 72, and
lower lugs 74 are particularly important with respect to the
operation of the embodiment of the invention described in FIGS.
1-3. However, these relative angular positions can be used to
advantage in the embodiment described hereinafter in connection
with FIGS. 6, 7, 8. Thus one of the upper lugs 72, hereinafter
referred to as hinge lug 80, is substantially centered with respect
to the center line 81 of hinge 64 and lug 80 extends around skirt
wall 68 through substantially the same arc which encloses hinge 64.
In the illustrated embodiments, lower detents 74 include lugs 82,
82 and an opposite pair of lugs 84, 84. Lugs 82 are those lower
lugs 74 which are closest to hinge-lug 80. Lugs 82 are angularly
spaced apart from hinge-lug 80 by a substantial arc. In the
illustrated embodiment the bead-retaining portions of lower lugs 82
do not begin within an arc which is about 20.degree. from the
center line 81 of bridge 64. It will be noted that lower lugs 82 do
not overlap hinge-lug 80.
Diameter line 83 is shown at right angles with center line 81. The
second pair of lower lugs 74 are those lower lugs 84, 84, which are
more or less diametrically opposite lugs 82, 82, respectively. It
will be noted that lugs 82 are circumferentially spaced apart from
lugs 84. In the illustrated embodiment, the centers of respective
lugs 82 are more than a quarter circle arc away from the center of
the respective nearest lug 84. In the illustration of FIG. 9,
diameter line 83 is shown substantially at right angles with
respect to center line 81. Thus, in the illustrated embodiment,
circumferentially adjacent respective lugs 82, 84 are positioned to
begin approximately 40.degree. on opposite respective sides of line
83. Thus the side regions 85 of skirt 56 are completely free of
neck-engaging detent lugs 74 such as lugs 82, 82, 84, 84. However,
the sides may be free of detents 74 in accordance with this
invention for a greater or smaller arc than that illustrated. It is
preferred, however, that the detent free arc extend at least about
20.degree. on either side of line 83. In addition to the upper
hinge-lug 80, several other upper lugs 72 are more or less randomly
positioned around the circumference of skirt 56.
A second preferred embodiment is illustrated in FIGS. 6, 7 and 8.
In these illustrations many of the elements and structures are
obviously substantially identical to those described hereinbefore,
and these substantially identical elements will be identified with
primed numbers corresponding to those used to reference previously
described elements and structures.
Flat central portion 54' of metal closure panel 46' includes
relatively small perforation 90 near its periphery. Perforation 90
is positioned to lie radially inwardly of sealing gasket 48 below
either hinge 64'or lift ring 60' (See FIG. 7). Adhesive 92 seals a
portion of the lower face of hinge 64' or lift ring 60 to the upper
surface of flat portion 54' in a zone completely surrounding
perforation 90, providing a hermetic seal around perforation
90.
OPERATION
Operation of the embodiment described in FIGS. 1-3 will be
described with the aid of FIGS. 4-5 and operation of the embodiment
described in FIGS. 6-7 is further described in FIG. 8, and in the
discussion below relating to FIG. 8.
When, in accordance with the use of this invention, lifting ring 60
is disconnected from planar flange portion 58 by breaking of
bridging portion 62, 62 (See FIG. 4), hinge 64 can transmit axially
directed forces directly to skirt 56. As perhaps best appreciated
from a consideration of FIG. 5, the direction in which force is
applied, when lifting ring 60 is substantially perpendicular to end
panel 57 of package 20, is substantially parallel to the elongated
(axial) dimension of skirt 56. It will be appreciated that the
initial forces which are thus supplied will be concentrated at
hinge-lug 80 which is positioned centered with hinge 64. It will be
further appreciated that the initial lifting forces, because of the
flexible quality of the fitment 44, will cause skirt 56, in the
immediate region of hinge 64, and hinge-lug 80, to flex upwardly
even though fitment-retaining lugs 82 remain engaged below neck
flange 43. This concentration of lifting forces at that portion of
metal closure 46 which engages hinge-lug 80 tends to peel the
relatively stiff closure panel 46, and more specifically gasket 48,
bonded to panel 46, away from end finish 34 (See FIG. 5). It is
noted that a small clearance between planar flange portion 58 of
plastic fitment 44, and opposing portion of metal closure panel 46
comes advantageously into play during this phase of the lifting
operation. It should be emphasized that it is not essential to
provide such clearance, and flange portion 58 can bear against
closure panel 46, if desired. If the clearance is provided, the
closure panel 46 can be peeled upwardly slightly before those
portions of rigid closure panel 46 above lugs 82 actually engage
fitment top panel 58. Not until rigid closure panel 46 engages
fitment top panel 58, above lugs 82, are the axially upward lifting
forces exerted through hinge 64, transmitted both through closure
panel 46 and through dependent skirt 56 to fitment-retaining lugs
82. Prior to this, however, the vacuum is broken. Hence, as a
consequence of the described cooperative structural and physical
property relationships of the elements of this invention, bonded
gasket 48 is lifted slightly from end finish 34 to break the vacuum
within sealed package 20 prior to substantial urging of plastic
fitment-retaining lugs 82 over fitment-retaining flange 43. As a
result, substantially all the initially exerted axial forces are
applied to breaking the vacuum, and once the vacuum is broken, only
those axial forces necessary to ease fitment-retaining lugs 82, 84
over neck flange 43 need be applied.
The operation of the embodiment shown in FIGS. 6-7 is illustrated
in FIG. 8. When, in accordance with the use of this preferred
embodiment of this invention, lifting ring 60' is disconnected from
planar flange portion 48' by breaking of bridging portions 62', 62'
(See FIG. 8) hinge 64' is peeled away from flat central portion 54'
of metal closure panel 46'. As bridging portion 64' is peeled away,
adhesive 92 separates, thus opening perforation 90 and breaking the
vacuum. In the embodiment illustrated in FIGS. 6-7, it is also
apparent, therefore, that the embodiment provides means for
breaking the vacuum which are responsive to lifting of ring 60'
prior to urging of fitment-retaining lugs 74' around
fitment-retaining flange 43'.
Thus, both of the preferred embodiments described hereinbefore
include means, responsive to the lifting of ring 60, 60' for
releasing the vacuum within sealed package 20, 20' before
closure-retaining lugs 74, 74' are moved over cooperating
closure-retaining neck flange 43, 43'.
As indicated above, preferred embodiments of the invention do not
include fitment-retaining lugs 74 along the sides 85 of the fitment
44. By "sides" of the circular fitment is meant those portions
along the circumference of the fitment, e.g., 90.degree. arcs,
which are most distant from a center line 81 of fitment 44 drawn
through hinge 64. Thus, this feature is provided, preferably, with
either of the embodiments disclosed in FIGS. 1-3 and in FIG. 8.
It is not intended that the invention be limited by any theories.
However, the elimination of fitment-retaining lugs at the sides of
the fitment 44 in accordance with this invention is believed to be
particularly advantageous during the removal of composite closure
24 at that state of separation after fitment-retaining lugs 74 are
initially eased around fitment-retaining bead 43. It has been
observed that the initial peeling of composite closure 24 from end
finish 34, with the inherent tendency of fitment 44 to flex, causes
the side portion 85 of skirt 56 to be urged radially inwardly. It
has been discovered that this radially inward urging of the side
portions 85 of skirt 56, caused inordinate binding of any detents
provided at the sides, caused bottom extremes to tend to cup around
bead 43, and thus cause a combination of factors working against
easy removal of closure 24. Thus, elimination of fitment-retaining
lugs 74 from the side region 85 of skirt 44 greatly facilitates the
continued peeling of composite closure 24 from neck 30. During the
final stages of removal of composite closure 24, therefore, the
closure is not necessarily moved axially, but tends to be moved
radially during disengagement of the last fitment-retaining lugs 84
from flange 43. Another possible explanation for the greatly
improved performance of the preferred closures of this invention is
that elimination of the side neck-engaging detents from skirt 56
may permit the bottom sides of the skirt to flex inwardly move
easily during the initial axial pull, thus better allowing that
portion of the skirt 56, especially near bottom bead 70 and
adjacent the tab hinge 64 to flex outwardly and be more readily
flexed upwardly to break the seal in the embodiment of FIGS. 1-4,
and then be eased over flange 43.
It will be appreciated from a consideration of FIGS. 1, 2, 3 and 5
that the peripheral flange 58 of plastic fitment 44 overlays a
peripheral portion 50 of closure panel 46, and that bead 78
overlays the inner extreme of upwardly opening recess 52. Thus, in
the illustrated preferred embodiment, boss or bead 79 defines an
outer limit of a complex stacking ring association of elements
which is actually a combination of the two members, namely fitment
44 and closure panel 46. Thus outer boss 79 of plastic fitment 44
acts in cooperation with upwardly opening, concave recess 52 in
closure panel 46 and radially inward bead 78 to define a composite
annular stacking groove. Thus a mating bottom (not shown) of a like
package can rest in, and be stabilized by, the composite stacking
ring described hereinbefore.
In the embodiment illustrated in FIGS. 6-8 vacuum release opening
90 is shown off-center with respect to closure panel 46. It is to
be understood that such positioning is not essential. For example
opening 90 and the cooperating area on fitment 44 can be centered
with respect to metal closure panel 90. The latter positioning has
a substantial advantage in that it would not require that panel 46
and plastic fitment 44 be in any specific angular alignment.
Plastic bridging portions 62 are preferably narrow, as illustrated,
to facilitate breaking, and to facilitate the flexing of panel 57
so that narrow portion 58 of lift ring 60 can reside within
depression 52 to provide some shock absorbing function when a
plurality of packages of this invention are in stacked
configuration.
As indicated in the drawings, it is preferred that shirt 68 and
bead 70 extend downwardly to close proximity with shoulder portion
28 or an equivalent structure on container 22, so that fingers
cannot get under the edge.
* * * * *