Note: Descriptions are shown in the official language in which they were submitted.
~~~~5~8
The present invention relates to an improved easy, open
end wall for a beverage container.
Beverage containers are well known in the art and are
widely used throughout the world. The present invention
deals with the type of beverage can which is widely used for
beer and soft drinks and is normally fabricated of a metallic
material such as aluminum or steel or alloys thereof.
To provide access to the contents of the container many
different closure systems have been proposed in the art. For
a long period of time, a tear strip was used whereby the
tear strip was removable from the end wall of the can with or
without an attached tab. These type of..tear strips became
obsolete since they were frequently discarded by the public
tending to create litter problems as well as posing hazardous
scenarios at beaches and parks.
Following the banning of tear strips by many
jurisdictions, the industry went to alternatives such as
arrangements wherein the tear strips and tabs are secured in
a non detachable manner to the container. One structure
which has received wide usage is the provision of a panel
which is non detachably secured to the end wall. With this
structure, the panel is subject to an inward force by means
of a tab member functioning as lever whereby the panel is
pushed inwardly, but remains attached at one~or more points
to the end wall. As mentioned, several of these designs have
received wide commercial usage; they suffer from the
disadvantage that since the tab is pushed inwardly, the
exterior surface of the panel contacts the contents of the
container and any foreign contaminants thereon may be allowed
1
202358
to enter the container.
It is also known in the art to provide an end wall
closure system wherein there is provided a panel which
utilizes a tab member to initiate opening of the panel in a
manner similar to the aforementioned systems, but wherein the
panel is removed exteriorly of the end wall such that the
contents of the container cannot be contaminated. Such a
system is illustrated in U. S. Patent 4,207,991 to Amabili.
The present invention is directed to such a system wherein
the tear initiation requires less force and wherein
accidental detachment of the panel is prevented.
In one aspect of the present invention, there is
provided an improvement in a closure system which includes an
end wall, a line of weakening within the wall defining a
removable panel, a tab member overlying portion of the end
wall and removable panel and with the tab member being
secured to the end wall near one extremity of the tab. At
the other end of the tab there is provided a finger engaging
portion, while intermediate the point of securement and the
finger engaging portion the tab member is secured to the
removable panel such that lifting movement of the finger
engaging portion will cause the tab member to start tear
initiation along the line of weakening to permit removal of
the panel. The improvement particularly comprises a
removable panel which has a first major portion thereof
adapted for dispensing of the container contents and a second
minor portion forming the area where the tab is secured to
the removable panel. The minor portion has its outer margin
substantially defined by a relatively small radius curve.
2
2~~~~~~
This small radius curve joins a curve defining the major
grortion of the panel. The curve defining the minor portion
and the curve defining the major portion are joined by a
curved section which reverses itself. This configuration
permits easier opening of the end by concentration of the
forces exerted.
In another aspect of the invention, there is provided an
improved tab member which limits upward movement of the tab
to prevent accidental removal of the tab and attached panel.
In greater detail, the closure or container end of the
present invention may be employed with any suitable container
such as is generally found in the soft drink and/or beer
industry. In particular, the closure is suitable for use
with metallic cans of a steel or aluminum material.
The end wall of the closure is sealed on one end of the
container in a conventional manner. In this respect, the
securement of end walls to the containers is well known in
the art and does not form a portion of the present invention.
The end wall may be formed of suitable metallic materials and
generally would be selected from known suitable alloys of
steel and/or aluminum material; the use of such materials is
well within the skill of those knowledgeable in the art.
Generally, it is preferred that the closure or end be of the
same material as the body of the container to permit ready
recycling of the complete unit although it is also known in
the art to employ separate materials with suitable provisions
being made during the recycling process. A dispensing
aperture is formed in the end wall; this aperture formed by
removal of a panel formed therein. Conventionally, the panel
3
2023~~~
is defined by a line of weakening such as a score line. In
other words, the panel is formed integrally with the end wall
and it is removable by forces applied to the score line to
permit removal of the panel.
The use of such weakening lines or score lines is again well
known and will not be elaborated on herein.
The tab member overlies at least a portion of the
removable panel and the end wall. The tab member is secured
to both the removable panel and the end wall. The tab member
has at one end thereof a finger engaging portion which will
exert force on the panel in a manner described hereinbelow.
Securement of the tab to the panel..and the end wall may
be accomplished by many means such as adhesives and/or
meahaniaal means. In the preferred embodiment, embossed
rivets integral with the end wall and or panel are utilized.
Such embossed rivets are shown, for example, in Canadian
Patent 1,005,004 to Cudzik issued February 8, 1987.
The tab member may be formed in several different
manners and is preferably of a material compatible with the
material forming the container body and the balance of the
container system - i.e. the end wall. The tab may be of
several different configurations although, as is
conventional, a somewhat elongated shape is preferable. The
tab member may include reinforcing ribs and the like, the use
of which technology is well known in the art.
The tab member is adapted to be lifted at the finger
engageable end thereof such that a force is exerted on the
rivet attaching the tab to the removable panel to cause a
tear initiation along the line of weakening defining the
4
2023~8~
removable panel. A continued lifting action on the finger
engageable portion will cause the panel to shear completely
along the line of weakening while remaining attached to the
end by means of the rivet securing the tab to the end.
The configuration of the removable panel is of
importance to permit the easy removal thereof. In this
respect, the panel of the present invention can be considered
to have a "major" portion and a "minor" portion. The major
portion, as the name implies, forms a portion through which
the contents of the container are dispensed while the minor
portion is where the panel is attached to the tab. The minor
portion is sized to be not substantially larger than required
for attachment of the tab.
As will be described in greater detail in the preferred
embodiment, the minor portion is defined by an arcuate line
of weakening, which arcuate line of weakening changes
direction so as to concentrate the forces exerted on the
panel through a lifting action of the tab on a relatively
short segment of the line of weakening.
The tab member of the present invention is also designed
to substantially reduce the possibility of accidental removal
of the tab and attached panel from the end. This is done by
provision of a nose member at the opposite extremity of the
tab from the finger engagable portion which will engage the
end wall to limit movement of the tab and thereby preventing
excess forces from being applied thereto.
Having thus generally described the invention, reference
will be made to the accompanying drawings illustrating an
embodiment thereof, in which:
5
Figure 1 is a top plan view of a container end according
to the present invention;
Figure 2 is a plan view similar to Figure 1 following
opening of the end;
Figure 3 is a detailed plan view of that portion of the
end indicated by arrow 3 in Figure l;
Figure 4 is a cross sectional view taken along the lines
4-4 of Figure 1;
Figure 5 is a cross-sectional view taken along the lines
5-5 of Figure 3;
Figure 6 is a sectional view of that portion of Figure 4
illustrated by arrow 6;
Figure 7 is a sectional view similar to Figure 6 showing
opening of the container end;
Figure 8 is an end view taken along the lines 8-8 of
Figure 7; and
Figure 9 is an enlarged plan view of the removable
panel.
Referring to the drawings in greater detail and by
reference characters thereto, there is provided a container
end 10 which comprises a wall portion 12 and a rim portion
14. End 10 is designed to seat in a conventional fashion on
a container such as is partially shown in Figure 5 wherein
rim 14 and a side wall 15 of a container are rolled together
for sealing. It will be understood that any other suitable
sealing means may be employed.
As is known in the art, end 10 has a removable panel 16
to thereby give a dispensing aperture through which access to
the contents of the container may be gained.
6
~~~58~
The removal of panel 16 leaves a dispensing aperture 17
which consists of a major portion generally designated by
reference numeral 18 and a smaller minor portion generally
designated by reference numeral 20. The entire removable
panel 16 is defined by score line 22. The formation of such
score lines or lines of weakening is conventional in the art
and need riot be discussed herein.
Lying adjacent to an exterior surface of wall 12 is a
tab member 32. Tab member 32 has an outer rim portion 34
which is formed by folding over the edges of the tab. Tab
member 32 has a generally elongated outline and includes a
finger engaging portion which is generally designated by
reference numeral 36 and which finger engaging portion
includes an aperture 38 formed therein. Aperture 38 permits
the user to more easily grasp this end of tab member 32.
At an opposed end of tab member 32 there is provided a
nose portion 48 while intermediate finger engaging portion 36
and nose portion 48 is a central tab portion 40. Central tab
portion 40 has a three sided cut line to permit lifting of
the tab as will be described hereinbelow. This portion of
the tab is secured to panel 16 by means of rivet 44. Rivet
44 is preferably provided by means of embossing in a manner
known to those knowledgeable in the art.
Adjacent nose portion 48 is a further rivet 50 which
functions to secure the entire tab portion to wall 12.
Again, rivet 50 is formed in wall 12 by means of embossing in
a conventional manner.
Nose portion 48, as may be seen from Figure 6, has a
first planar portion 52 which lies generally in the same
7
2a~~~$~
plane as the remainder of the tab. From planar portion 52,
it extends upwardly through portion 54 and subsequently
downwardly (portion 56) to terminate again in a planar
portion 58 which generally lies in the same plane as planar
portion 52. This enlarged nose portion 48 functions to
limit the upward movement of the tab by entering into
engagement with wall 12. This limitation of the upward
movement is designed to prevent removal of the tab and
attached panel even after repeated motions.
The limitation of the upward movement may also be
accomplished by providing a raised land portion on wall 12
which nose portion 48 will engage. In this respect, a raised
land portion may be configurated, alone or in conjunction
with the shape of the nose, to prevent the upward movement of
the tab beyond a certain point. Naturally, the limitation of
the upward movement is such that the tab will form an angle
less than 90 degrees with respect to end 12. Preferably,
this angle is limited to less than 75 degrees and even more
preferably 60 degrees to prevent the possibility of
sufficient stress being applied to the metal to permit
cracking of the same.
Referring to Figures 1, 2, 7 and 8, opening of the
container is accomplished by the user lifting finger engaging
portion 36. The force is transmitted through rivet 44 to
panel 16 which will be more fully described hereinbelow.
This force causes a tear initiation to begin proximate rivet
44 and a continued lifting/pulling force exerted on tab
member 32 causes the panel 16 to shear completely along score
line 22 to completely detach the panel from end wall 12.
8
Subsequently, as shown in Figure 2 by arrow 17, the tab with
the attached panel may be pivoted about rivet 50 to an out
of way position as shown in Figure 2. Thus, tab 32 functions
as a second class lever.
As previously mentioned, nose portion 48 is designed to
engage with wall 12 to limit the upward movement of tab 32
to the extent that is needed to permit removal of panel 16.
Because this movement is limited, even continued flexing of
the tab would not cause breakage of the tab to permit
discarding of the same. Generally, this tab is designed to
limit movement to less than 90 degrees and more preferably to
less than 75 degrees.
The configuration of the panel 16 and placement of the
rivet with respect thereto are of importance and will now be
described in greater detail. In this respect, reference may
be had to Figure 9 which is an enlarged view of panel 16
which is defined by score line 22.
As previously described, panel 16 has a major portion 18
and a minor portion 20. For purposes of discussion,
reference line 60 has been drawn between the two portions;
this reference line 60 is for purposes of explanation only
and does not constitute any physical marking on the removable
panel 16. Reference line 60 is only an approximation and is
not intended to be a precise position on the panel 16. In
Figure 9, points ABCD and E are used to define line segments
far purposes of discussion of the operation of the
invention.
The major portion 18 of removable panel 16 is generally
defined by segment ABCD while minor portion 20 is defined by
9
CA 02023588 2001-12-07
line segment DEA.
Line segment ABCD is of a continuous arcuate configuration as is known in
the art to provide for easy shearing. Line segment DEA, is also a continuous
arcuate
configuration.
Rivet 44 is formed to secure removable panel 16 to tab member 32.
As noted, line segment DEA is arcuate with the curve generally continuing in a
single direction. Similarly, line direction ABC also has an arcuate
configuration with
the curve generally continuing in the same direction. Line segment CD,
however, has
a "reverse" arcuate configuration - i.e. the curves reverse direction between
the two
portions. Adjacent point D, the curve has a concave configuration or section.
In the opening of the container, it is desirable to concentrate the force
which is
being transmitted through rivet 44 from tab member 32 to as small an area as
possible.
The configuration of the panel 16 shown in Figure 9 functions to do this.
Thus, the
force exerted by rivet 44 is generally concentrated on the line segment DE.
The
reverse arcuate configuration prevents this force from being dissipated or
spread over
a larger segment which would be the case if the direction of the curve of
score line did
not reverse itself. Its concentration of the opening force permit the tear
initiation to
commence following which it is relatively easy to continue with the shearing
and
removal of panel 16.
The reverse arcuate configuration is shown as only being on one side of panel
16. It has been found that it is only necessary for the one side as the force
is generally
2n~~5g~
concentrated on one side. However, if so desired, a similar
Configuration could be utilized on the other side.
As may be seen from Figure 9, major portion 18 has a
major axis as shown by dotted line 64. Minor portion 20 as
described above, is sized to be not substantially larger than
requirements for the formation of the rivet therein. Thus, a
somewhat diametrical line extending through rivet 44 and
which intersects the major axis 64 of major portion 18 within
the boundries of the removable panel will form an angle of
between 15 degrees and 105 degrees.
The side of the line of weakening having the reverse
arcuate section is that side to which the force is first
applied. In other words, the force is first applied to line
segment DE with the lifting force (i.e. the finger engaging
portion) being located on that side.
It will be understood that the above described
embodiments are for purposes of illustration only and that
changes and modifications may be made thereto without
departing from the spirit and scope of the invention.
11
