Bottle cap with ring shaped tearing element

A tear tab closure for containers comprises a cap having a top, a downwardly depending skirt, a tear tab projecting from the skirt and terminating in a finger ring. The tear tab is relatively short and the finger ring is secured thereto by any suitable mechanical or adhesive fastening means. The finger ring is of large enough inside diameter to facilitate capture of the finger ring by a finger of the user and it may be disposed to lie at the side of the container or it may be large enough in diameter to encircle the container in close proximity thereto.

BACKGROUND OF THE INVENTION 
The present invention relates to closures for containers and more 
particularly to tear tab closures for bottles and the like for containing 
fluid under pressure. 
For a tear tab closure to be practical, it is essential that the tear tab 
be capable of being gripped easily but securely by the finger of the user 
and manipulated to open the closure effectively under unfavorable 
conditions with minimum risk of injury to the user. In the past, attempts 
have been made to achieve these objectives by using a relatively long tear 
tab provided with parallel embossings in the form of pyramids, ridges, or 
the like disposed perpendicularly to the tearing direction, as shown in 
prior U.S. Pat. Nos. 1,052,382 to Schmitt and 2,068,444 to Breckenridge. 
It is often difficult for such tabs to be gripped and manipulated properly 
even by a person of normal motor ability and muscle strength. Also, under 
unfavorable conditions, as where the finger of the user or the tear tab is 
wet, there is risk of injury in the event the fingers of the user slip. 
Moreover, it is possible for the tear strip to be torn open accidentally 
if the tab projects from the container and catches against the edge of a 
table or the like. 
It has also been proposed to use caps having a tear tab terminating in an 
integral circular ring adapted to receive a finger of the user, as 
illustrated in prior U.S. Pat. Nos. 3,380,609 to Potts, 3,785,519 to Huh, 
and 3,974,931 to Moller. These caps, however, are very difficult to make 
and therefore very expensive. Moreover, both they and caps having long 
tear tabs require complicated machinery in their manufacture. 
SUMMARY OF THE INVENTION 
It is an object of the invention, accordingly, to provide a new and useful 
tear tab closure for bottles and the like which is essentially free from 
the above noted deficiencies of the prior art. 
These and other objects of the invention are achieved by providing a tear 
tab closure having a tear tab with a relatively short free end to which is 
secured a finger ring of a size to accommodate the finger of a user 
comfortably and made of a material thicker than the tear tab so as to 
possess sufficient tensile strength and to minimize the likelihood of 
injury to the user. The finger ring may normally lie at one side of the 
container, depending downwardly from the tear strip end to which it is 
secured. Alternatively, it may be large enough in diameter so that it can 
be disposed normally to surround the neck of the container on which it is 
mounted in relatively close proximity thereto. 
Because of the reduced length of the tear tab free end, a substantial 
saving of material can be achieved in the manufacture of tear tab closures 
according to the invention, as compared with tear tab closures having an 
integral finger ring. Also, since the seal can be formed in the cap before 
the finger ring is attached to the tear tab, the undesirable accumulation 
of sealing material at the root of the tear tab which sometimes occurs 
with closures having integral finger rings because of the lever action of 
the tab and ring is eliminated.

The closure shown in FIG. 1 is made of thin, light metal and comprises a 
disc shaped top wall 10, a substantially cylindrical skirt 11 which 
surrounds the top wall, and a tear tab 12 projecting from the skirt 11. 
The free end of the tear tab 12 need only be long enough to enable a 
finger ring to be fastened thereto, and preferably it tapers away from the 
skirt 11 from its base adjoining the skirt to its free end. To facilitate 
tearing the cap open, a finger ring 13 is attached to the free end 14 of 
the tear tab 12, and score lines 15 and 16 (FIG. 2) extend from locations 
on each side of and immediately adjoining the root of the tear tab 12, 
across the skirt 11, and over the top wall 10. 
The score lines are not part of the invention and they may follow any 
arbitrary route which may be symmetrical or asymmetrical, they may contain 
mutually converging or mutually diverging sections, and they may be of 
different lengths. Also, the cap blank may be provided with a sealing 
insert which may be suitably bonded to the undersurface of the cap by 
means of an adhesive lacquer or the like. The sealing insert may cover the 
top section completely, but if the score lines substantially follow the 
bead which surrounds the aperture of the bottle to be sealed with the cap, 
the insert may preferably consist of a ring seal. 
The finger ring should preferably be made of plastic, in particular 
reinforced plastic, and it should be large enough to accommodate the 
finger of the user comfortably. To this end, its inside diameter should be 
greater than the width of the tear tab 12, and should preferably exceed 
approximately 12 mm. In a practical closure, the inside diameter may be 
approximately 16-18 mm. 
The ring thickness need only be great enough to avoid the risk of breakage 
at the time of pulling, and also the risk of injury, or at least of 
discomfort, to the user when the ring is pulled for the purpose of tearing 
the cap. Thus, typically the thickness of the ring may be approximately 
0.6-1.0 mm and its width in the radial direction may be approximately 
1.2-1.8 mm, but these values are intended only to give guidance as to 
preferred dimensions, and greater or smaller dimensions may be used. 
In FIG. 1, the ring 13 is attached to the free end of the tear tab 12 by 
curling, but it may equally well be attached by riveting, gluing, or any 
other well-known method, or by combinations of such methods. Since the tab 
12 serves only as anchorage for the ring 13, it should preferably be much 
shorter than a conventional tear tab, resulting in a substantial saving of 
material in the manufacture of the cap. Furthermore, the ring 13 should be 
attached to the free end 14 of the tab so as to form a substantially 
linear extension of the latter, and normally it lies at one side of the 
closure as shown. 
If desired, the finger ring may be made large enough in diameter to be 
swung over the top of the closure so as to encircle the top of the 
container in relatively close proximity thereto, as shown in FIG. 2. In 
use, the ring 13' can be twisted from its position under the skirt 11, 
around the axis of its hinged anchorage in the free end 14 of the tear tab 
12, to a position which allows the ring to be gripped by the user and 
pulled for the purpose of tearing the cap. 
It is important that the rings 13 and 13' be located some distance away 
from the skirt 11, as shown in FIGS. 1 and 2, if difficulties are to be 
avoided in clamping the skirt against the bead at the bottle opening. Once 
the capping process has been completed, the orientation of the ring in 
relation to the skirt can, of course, be altered, if desired. For example, 
the tab 12 can be bent in such a way that the ring 13 is brought downwards 
and inwards towards the neck of the bottle, and the ring 13' can be 
brought upwards to surround the skirt section 11. Also, the side of the 
ring which is opposite the tab may be detachably fastened in any suitable 
way. 
In the form of the invention shown in FIGS. 3 and 3a, the finger ring 13" 
may be made of a material such as aluminum wire, for example, shaped to 
have adjacent, upwardly extending ends 17 and 18 separated by a small gap. 
The ends 17 and 18 are adapted to be inserted through spaced holes or 
slits 19 and 20 formed in the tear tab 12 and bent parallel to the ring 
13" so as to secure the ring to the tab. 
The attachment of the ring 13" to the tab 12 can be further strengthened by 
curling the end 14 of the tab 12 over the bent back wire ends 17 and 18 as 
shown in FIG. 3a. In addition, the attachment may be made even more secure 
by pressing and/or stamping the curled tab end 14 over the ring ends. 
The ends of the ring 13" in FIGS. 3 and 3a, for instance, can be attached 
to the tab in such a way that they overlap. Also, the ends of the ring can 
be joined to the tab in a hinge-like fashion by inserting the ends 17, 18 
of the wire into two holes disposed at a distance from each other across 
the width of the tab, or by some similar arrangement. Of course, the ring 
13" can also be inserted into the tab 12 from the opposite side and the 
curling in FIGS. 1, 2 and 3a can be done towards the underside of the tab. 
If desired, the ends 17, 18 of the finger ring 13" may overlap each other 
in scissorlike fashion and be bent inwardly over the edges of the tab 12 
in such a way that they exert a certain amount of spring pressure on the 
tab edges, as shown in FIG. 4, suitable lateral notches 21 and 22 
preferably being provided to hold the ends of the ring in place. For 
greater strength, the ends 17, 18 of the wire ring 13" may be effectively 
secured to the tab 12 by any of the methods described above, such as 
pressing and/or stamping and subsequent curling of the end 14 of the tab 
over the wire ends. 
The invention thus provides a simple and highly effective tear tab closure 
for containers such as bottles and the like. By providing a tear tab 
terminating in a finger ring of a diameter to accommodate the finger of a 
user comfortably and made in a shape and of a material free from sharp 
edges, capture of the ring by the finger of a user may be effected with a 
minimum of effort and risk of injury. Also, since the finger ring need not 
be secured to the closure until after the seal has been formed, the usual 
accumulation of sealing material at the root of the tab that often occurs 
in the manufacture of tear tab closures having conventional integral, 
outwardly, projecting, long tear tabs may be totally eliminated. 
The specific embodiments described herein are intended to be merely 
illustrative and modifications in form and detail are, of course, 
possible. Thus, the finger ring may be made of other materials than 
plastic and it may be attached to the tab in a variety of different ways. 
For example, instead of curling the tab material around the ring, the ring 
may be fastened to the tab by riveting or gluing. Also, by the selection 
of suitable materials, it may, of course, be possible to melt the tab 
material and the ring material together. Furthermore, the tab and/or the 
ring may be provided with one or more ridges or similar protuberances, and 
the ring affixed by deformation of these ridges by cold-rolling or the 
like. In addition, the joint between ring and tab may be further 
strengthened by spot welding, and it is also possible to affix the ring by 
applying suitable corrugations to the tab. 
Another way of securing a ring to the short tab on a cap according to the 
invention is to bend the tab so that it extends substantially parallel to 
and away from the skirt. A circular band with overlapping ends is then 
positioned substantially coaxially with the cap so that the ends overlie 
the tab and the band is rolled into a ring enclosing the tab and securing 
the ring to the latter. 
It will be understood, of course, that the finger grip may comprise a loop 
or ring shaped flexible ribbon of plastic or similar material as shown in 
FIG. 5, which can be attached to the tab in any suitable manner, as by 
gluing, riveting, or melting together. Also, the finger grip may have a 
shape other than the practically circular shape shown in the drawings. For 
example, it may be pear shaped. The invention is intended to encompass all 
such modifications as fall within the scope of the following claims.