Note: Descriptions are shown in the official language in which they were submitted.
~A 2 1 1 7 3 1 7
BACKGROUND of the INVENTION.
Reference is especially made herein to hermetic
closures for containers having a small opening
provided on a dispenser, such as a spout, a spray,
a drop-counter and the like, where factory sealing
05 of the container is guaranteed by a safety device
that is broken on first use of the container.
This safety device is usually a detachable safety
strip connected to a a cap by easy-break struts,
which are fractured by an axial movement of the
cap in an upwards direction, that is to say in an
opening direction of the container. This usually
means an unscrewing movement.
Further, as the cap is generally made in fairly
rigid plastic material, not normally able to
ensure a good isolation of the contents inside the
container, the hermetic efficiency of the closure
is instead guaranteed by such systems as contact
between the internal surface of the upper part of
the cap and the upper surface of the dispenser and
the container.
Some examples of such containers are tubes and
flagons for pharmaceutical products such as
eyedrops, ointments, solutions, and so on.
CA2117317
One of the drawbacks presented in known closures
is that it is often possible slightly to unscrew
the cap, enough to cause the seal to be broken
while not sufficiently to make it obvious to a
05 consumer that the seal has in fact been broken. In
pharmaceutical products especially this can mean a
crucial loss of sterility which may go unnoticed
at first.
In bottles such seal breakage can be achieved by
simply squeezing the bottle and releasing it, so
that it functions as a suction pump. With rigid
containers, it may be enough to immerse them fully
in a bath containing sufficient fluid for them to
lose their purity. In short, in the above case the
mere presence of an unbroken safety strip is not a
guarantee that the container has not been tampered
with.
A principal aim of the present invention is to
obviate the above drawback, by providing a
hermetic closure with a plastic cap assembly, for
containers having dispenser devices, in which the
integrity of the safety guarantee device is a true
guarantee that no violation has taken place, and
also that none of the container contents have
escaped nor extraneous contents been introduced.
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One advantage of the invention is that it provides
a constructionally simple closure while achieving
its set aim, so that no utilization complications
arise from it.
SUMMARY of the INVENTION.
05 The above aims and more besides are fully attained
by the closure of the invention, as it is
characterized in the claims, in which, as in known
closures, a cap assembly is provided, equipped
with a cap which when unscrewed causes detachment
of a safety strip, and which comprises a seal
that, when the cap is inserted on the container,
guarantees a seal on a lateral wall of the
dispenser of the container, even when said cap is
subject to small axial displacements with respect
to the container.
BRIEF DESCRIPTION of the DRAWINGS.
Further characteristics and advantages of the
present invention will better emerge from the
detailed description that follows, of a preferred
but non-exclusive embodiment here illustrated in
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the form of a non-limiting example in the
accompanying drawings, in which:
figure 1 is a partially-sectioned schematic
vertical elevation view of a first embodiment of
05 the invention;
figure 2 is a partially-sectioned schematic
vertical elevation view of a second embodiment of
the invention.
DESCRIPTION of the PREFERRED EMBODIMENTS.
In the figures and the following description
reference is made to a particular type of closure
assembly, by the novel concept expounded
hereinbelow is intended to be applicable to all
closure assembly types for containers equipped
with dispensers which comprise plastic cap
assemblies in which a detachment of a safety strip
is provided as proof of the pristine conditions of
the container contents, and where the separation
of the safety strip is achieved by moving the cap
axially upwards.
The closure assembly of figure 1 comprises a cap
assembly 10 applied on a container having a neck 9
and a dispenser 7. The cap assembly 10 is composed
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of two plastic parts, which are assembled on
insertion of the whole cap assembly 10 into the
container neck 9. Figure 1 shows the cap assembly
10 mounted on the container before the container
05 has been opened for a first time.
The cap assembly 10 comprises a first part
constituted by a cap 1, which is generally used to
reclose the container once it has been opened for
the first time.
The cap 1 is generally manufactured by pressing of
plastic material and is provided with an internal
thread which couples with an external thread
provided on a container neck 9.
The cap assembly 10 further comprises a second
part, constituted by an annular element consisting
of a ring 3 which when the cap assembly 10 is
united joints into an annular seat fashioned in an
internal wall of the cap 1. The annular element
comprises a safety strip 4 coaxially connected
with the ring 3 by means of easy-break struts 5,
which when broken testify that the container has
in fact been opened.
The safety strip 4 is provided with a lip 12
destined to interact, when the cap 1 is unscrewed,
with an annular protruberance 13 provided on the
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container neck 9.
On first unscrewing, the cap 1 is raised and draws
the ring 3 and the safety strip 4 with it for a
certain distance, up until when the lip 12 of the
05 safety strip 4 comes into contact with the
protruberance 13 of the neck 9. As the unscrewing
procedure continues, the struts 5 are stretched by
traction in the opening direction of the cap 1 up
until they break and the safety strip 4 detaches
from the rest of the cap assembly 10.
The above-described is a normal opening procedure
utilized by many known closure assemblies.
On an external lateral surface of the dispenser 7,
and at a certain distance from the container
mouth, the first embodiment of the present closure
assembly comprises a seal ring 6 fashioned from
the plastic of the dispenser 7 neck and
interacting with an internal lateral surface of
the cap 1. The seal ring 6 provides a seal against
the internal wall of the cap 1, at least when the
cap 1 is moved axially upwards over distances
which do not exceed a minimum displacement
distance necessary for a detachment of the safety
strip 4.
The seal ring 6 exhibits an external diameter
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which is not only greater than the internal
diameter of the contact zone, that is the annular
portion of cap internal wall with which the seal
ring 6 contacts when the cap assembly 10 is
05 mounted on the container, but also greater than
the maximum internal diameter presented by the
tract of wall exhibited by the cap 1 immediately
underlying the annular contact portion, which has
an axial length that is at least equal to the
minimum distance necessary to cause the struts 5
to break.
The cap 1 comprises a seal zone on the internal
lateral surface of the upper part of the cap 1
itself, (including the dispenser 7) which
lS interacts with the seal ring 6 up to when the
safety strip 4 breaks.
When the cap 1 is unscrewed by a short distance,
the safety strip 4 connected to it lifts freely up
to when the lip 12 contacts the protruberance 13
of the container neck 9.
During this operation, the seal zone of the cap 1
moves upwards, dragging on the seal ring 6 of the
dispenser 7. The seal zone of the cap 1 loses
contact with the seal ring 6 only when the cap 1
has been raised enough to break the struts 5.
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In known type closures, very small cap upwards
displacement is enough to break the seal between
container and cap.
Reutilization of the cap 1 restores the seal, as
05 in known cap assemblies.
Isolation of the container can be achieved by
means of a seal ring made not on the container but
on the internal lateral surface of the cap 1. In
this case the seal ring will have a smaller
internal diamter than the maximum diameter
exhibited by a tract of external lateral wall on
the dispenser 7. This tract, which will be axially
longer than a minimum displacement necessary to
break or distance the safety strip 4, will
constitute a zone of the dispenser 7 on which the
dragging of the safety strip 4 takes place.
Any deformable element can be used as a sealing
means of the cap on the container, and will be
interplaced between the external lateral surface
of the dispenser 7 and the internal lateral
surface of the upper part of the cap 1 covering
said dispenser 7. The determining factor is that
in each case the seal on the container should be
maintained over axial displacements between the
cap 1 and the container which must be at least as
- ~A21 17317
long as the minimum displacement of the cap
needed to break the safety strip 4.
Figure 2 shows a closure assembly of the same type
as the above-described assembly, comprising a
05 plastic cap assembly 10' in which the detachment
of the safety strip 4 occurs by unscrewing or
raising the cap of the cap assembly 10' itself.
The cap assembly 10', comprising a cap 1', is
applied on a container neck 9' and a container
dispenser 7', constituted in this case by a drop-
counter solidly inserted into the neck 9' to
enable drops of a liquid to be counted as they
exit the container. In the figure the cap assembly
10' is shown mounted but as yet unopened.
The dispenser 7' is cup-shaped and has a slightly
larger external diameter than the internal
diameter of the container mouth, which is forced
against the internal walls of the neck 9'. The cup
is superiorly provided with a flat annular crown
which strikes against the upper surface of the
container. On its bottom surface the cup exhibits
a small central hole for a passage of liquid drop
by drop, and a small internal tube for air
entrance.
The dispenser 7' further exhibits a coaxial
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11
cylindrical spout, arranged between the hole and
the tube, fashioned on the bottom of the cup and
facing externally of the container. A seal 8' on
the lower face of the cap 1' seals against the
05 flat annular crown and the spout of the dispenser
7'.
All of the aforegoing could be applicable to
known-type cap assemblies.
The closure assembly of the present invention,
shown in figure 2, comprises an annular element 6'
fashioned in relief on the internal lateral
surface of the cup of the dispenser 7', and
projecting inwards.
The annular element 6' is arranged on the upper
part of the cup and seals against the external
lateral surface of a coaxial cylindrical element
11' fashioned on the seal 8'. The cylindrical
element 11' faces inwardly of the cup and exhibits
a greater external diameter than the internal
diameter of the annular element 6'.
On the external lateral surface of the cylindrical
element 11', the cap 10' also comprises a seal
zone arranged immediately below the annular zone,
which comes into contact with the annular element
6' when the cap assembly 10' is mounted on the
CA 2 1 1 73 1 7
12
container. The seal zone is longer than the
minimum displacement required to break the safety
strip of the cap assembly 10'.
This embodiment also offers the possibility of
05 achieving perfect hermetic closure by means of a
seal ring fashioned on the cap instead of on the
container. In this case the seal ring would be
arranged on the external surface of the
cylindrical element 11' of the seal 8'.
Independently of the realisation, the seal occurs
between the external lateral surface of the
cylindrical element 11' and the internal lateral
surface of the dispenser 7', and is guaranteed for
relative axial movement between the cap and the
container over a distance that does not cause
detachment of the safety strip.
