Note: Descriptions are shown in the official language in which they were submitted.
2133292
TAMPER-EVIDENT CLOSURE
FIELD OF THE INVENTION
The present invention relates to a tamper-evident
closure.
BACKGROUND OF THE INVENTION
Tamper-evident closures of various types and designs
are well known devices that are used on containers to
provide an indication to the consumer that the container has
been open. Such closures generally include a cap portion and
a security ring portion connected to the lower edge of the
cap portion by a failure line. Typically the ring portion of
the closure comprises a plurality of tabs extending upwardly
and inwardly so as to abut against an annular flange that is
part of the neck of the container after the closure has been
screwed in sealing position. AS soon as someone tries to
remove the closure from the container, the failure line
breaks and causes the ring portion to separate from the cap
portion and thus give a visual indication that the container
has been open. Closures of this type are described, by way
of examples in U.S.Pat. Nos. 4,478,343
4,550,844
4,595,110
4,801,030
4,807,771
4,978,017
5,007,545
As can be easily understood, it is desirable for the
tamper-evident closures to be easily manufacturable at low
cost and be versatile for use with a large variety of
containers.
It is also desirable to obtain a tamper-evident closure
where the connection between the cap portion and the ring
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portion is more resilient upon screwing so as to facilitate
installation of the closure onto the container. Another
advantage sought in the conception of tamper-evident
closures is the obtention of a closure which allows the
failure line to break easily when someone tries to unscrew
the closure.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a
tamper evident-closure that satisfies these needs.
More particularly the invention provides a tamper-
evident closure for sealing a container, which have an
opening, a threaded neck portion and an outwardly extending
annular flange, the flange being adjacent to and beneath the
threaded neck portion.
This tamper-evident closure comprises a cap portion and
a ring portion.
The cap portion is sized to fit and be screwed onto the
threaded neck portion of the container. It has a top wall
and an annular skirt of given internal diameter that is
coaxial with and integrally projects from the top wall. The
skirt has a lower edge and is provided with an internal
thread sized and shaped to engage the threaded neck portion
of the container. In one embodiment of the invention, the
skirt also has a generally cylindrical exterior wall
provided with a plurality of gripping ribs.
The ring portion which is coaxial with the top wall and
the skirt of the cap portion comprises an upper ring, a
lower ring and a plurality of inwardly oriented wedges
positioned between the upper and lower ring.
The upper ring has the same internal diameter as the
skirt. It also has an upper edge and a lower edge, the upper
edge being connected to the lower edge of the skirt by
breakable connecting means. In a preferred embodiment of the
invention, the connecting means comprises a plurality of
frangible break-away bridges attaching the upper edge of the
21:~32~2
upper ring to the lower edge of the skirt. Between each pair
of bridges, the upper edge of the upper ring can be provided
with an axially extending protrusion which terminates short
of the lower edge of the skirt. The protrusions are adapted
to engage the lower edge of the skirt on application of an
axial force to the closure during installation and thus, to
protect the bridges from premature breakage.
The lower ring has the same internal diameter as the
skirt, and it also has an upper edge and a lower edge.
The plurality of inwardly oriented wedges are
circumferentially distributed and spaced apart from each
other in between the upper and lower ring. Each wedge has an
upper edge connected along a thin folding line to the lower
edge of the upper ring. It also has a lower edge connected
along another thin folding line to the upper edge of the
lower ring. And finally each wedge has an inwardly and
upwardly projecting apex positioned and sized to fit under
the outwardly extending flange of the threaded neck portion
of the container when the cap portion of the closure is
fully screwed onto the threaded neck portion.
In use, when the closure is screwed onto the container
to close the same, the wedges are allowed to move radially
outwardly thanks to the thin folding lines joining the
wedges to upper and lower ring and thus the wedges pass over
the flange of the neck. Then, the wedges return to their
original position where the apexes of the wedges extend
under the flange.
If or when someone tries to remove the closure, the
apexes of the wedges engage the flange of the neck and get
lock onto the flange, thereby causing the connecting means
to break and the ring portion to fall.
The tamper-evident closure according to the invention
may further comprise a disc-shaped liner having
substantially the same diameter as the opening of the
container. This disc-shaped is nested against the inside
` 21332Y~
surface of the top wall after cap portion so as to form a
seal between the closure and the opening of the container.
In another preferred embodiment of the invention, the
cap portion and the ring portion have an identical external
diameter, and are integral to each other and made of
thermoplastic.
A non restrictive description of a preferred embodiment
will now be given with reference to the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a tamper-evident
closure according to the invention;
FIG. 2 is a cross-sectional view taken along line II-II
of FIG.l;
FIG. 3 is a cross-sectional view taken along line III-
III of FIG.2;
FIG. 4 is a enlarged fragmentary, cross-sectional view
of the closure of FIG.l , where the same is
inserted onto the neck of a container to be
closed;
FIG. 5 is a view similar to FIG.4, showing the closure
in installed in installed position onto the neck
of the container.
DESCRIPTION OF A PREFERRED EMBODIMENT
The tamper-evident closure 10 according to the
invention as shown in the accompanying drawings is intended
to be used for sealing a container 40.
The container 40 which is shown in FIG.4 and 5
comprises an opening 41, a threaded neck portion 42 and an
outwardly extending annular flange 43 adjacent to and
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beneath the threaded neck portion 42. This basic structure
is rather conventional and needs not be further described.
The closure 10 comprises a cap portion 20 and a ring
portion 30.
The cap portion 20 is sized to fit and be screwed onto
the threaded neck portion 42 of the container 40, as shown
in FIG.4 and 5. It has a top wall 210 and an annular skirt
220 of given internal diameter that is coaxial with and
integrally projects from the top wall 210. The skirt 220 has
a lower edge 221 and is provided with an internal thread 222
sized and shaped to engage the threaded neck 42 portion of
the container 40. In the illustrated embodiment of the
invention, the skirt 220 also has a cylindrical exterior
wall 223 provided with a plurality of gripping ribs 224.
Once again, this basic structure is conventional and needs
not be further described.
In accordance with a very important aspect of the
invention, the ring portion 30 which is coaxial with the top
wall 210 and the skirt 220 of the cap portion 20 comprises
an upper ring 310, a lower ring 320 and a plurality of
inwardly oriented wedges 330 positioned between the upper
310 and lower ring 320. The cap portion and the ring portion
can have an identical external diameter as shown in FIG.1-5.
The upper ring 310 has the same internal diameter "d"
as the skirt 220. It also has an upper edge 311 and a lower
edge 312, the upper edge 311 being connected to the lower
edge of the skirt 221 by breakable connecting means 51 of
conventional structure. In the illustrated embodiment of the
invention, these connecting means 51 preferably consist of
plurality frangible of break-away bridges attaching the
upper edge 311 of the upper ring 310 to the lower edge 221
of the skirt 220.
The lower edge 221 of the skirt 220 and the upper edge
311 of upper ring 310 are also provided with a plurality of
axially extending, circumferentially spaced protrusions 52.
Each of protrusion 52 terminates short of the other one of
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the edges and is adapted to engage the other edge on
application of an axial force to the closure during
installation and thus, to protect the bridges from premature
breakage. Preferably, there is a protrusion 52 between each
pair of bridges 51, these protrusions 52 extending from the
upper ring 310.
In another not illustrated embodiment, the connecting
means 51 may comprise a portion of substantially reduced
cross sectional thickness, such as a groove.
The lower ring 320 has the same internal diameter as
the skirt 220, and it also has an upper edge 321 and a lower
edge 322.
As illustrated, the inwardly oriented wedges 330
joining the upper and lower rings are circumferentially
distributed and spaced apart from each other in between the
upper 310 and lower ring 320. Each wedge 330 has an upper
edge 331 connected along a thin folding line 333a to the
lower edge 312 of the upper ring 310. It also has a lower
edge 332 connected along another thin folding line 333b to
the upper edge 321 of the lower ring 320. Each wedge 330
further has an inwardly and upwardly projecting apex 335
positioned and sized to fit under the outwardly extending
flange 43 of the threaded neck portion 42 of the container
40 when the cap portion 20 of the closure 10 is fully
screwed onto the threaded neck portion 42, as shown in
FIG.5.
In use, when the closure 10 is screwed onto the
container 40 to close the same as shown in FIG.4, the wedges
330 are allowed to move radially outwardly thanks to the
thin folding lines 333 and 334 joining the wedges 330 to
upper 310 and lower ring 320. This allows the wedges 330 to
pass over the flange 43 of the neck 42. Then, the wedges 330
return to their original position where the apexes 335
extend under the flange 43, as shown in FIG.5, and get
locked there.
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As soon as someone tries to remove the closure 10 to
open the container, the apexes 335 of the wedges 330 engage
the flange 43 of the neck 42 and get lock onto flange 43,
thereby causing the connecting means 51 to break and the
ring portion 30 to fall.
As illustrated the closure 10 may also comprise a disc-
shaped liner 60 having substantially the same diameter as
the opening 41 of the container 40. This disc-shaped liner
60 nests against the inside surface of the top wall 210 of
the cap portion 20 and thus forms a seal between the closure
10 and the opening 41 of the container 40.
Preferably, the cap portion 20 and the ring portion of
the closure are integral to each other and made of
thermoplastic material. Such is well known in the art and
needs not to be further described.
Although a preferred embodiment of the invention has
been described in detail herein and illustrated in the
accompanying drawings, it is to be understood that the
invention is not limited to this precise embodiment and that
various changes and modifications may be effected therein
without departing from the scope or spirit of the invention.
