Note: Descriptions are shown in the official language in which they were submitted.
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Crown Cork AG, 4153 Reinach
Container closure and container mouth
The invention concerns a container closure, a container and a
combination of a container closure and a container according
to the preamble of the independent patent claims.
With industrial bottling plants, state-of-the-art closures
for the closure of containers are placed upon containers
intended for closure at high rates per hour. Placement se-
quences are the same with regard to principle elements,
regardless of whether snap or screw closures are concerned.
The closures are delivered by a so-called hopper and, by
means of a transfer device, placed upon the mouths of con-
tainers passing at high speed. In a subsequent process step,
depending on type, the closures are either pressed or screwed
onto the container mouth.
Because of the high speed of the passing containers, however,
problems can occur prior to firm placement of the closures.
The closures can tilt while being put onto the closure mouth,
or because of the high speed of the containers, they can jump
off the container mouth before being pressed on or screwed
on.
For example, plastic snap closures are proposed which possess
flexible clips on their insides, said clips enabling the
closure to be held upon a container mouth. Because of their
flexibility, these clips permit only inadequate holding of
the closure prior to actual placement onto the container
mouth. In particular, in bottling plants, with such clips
jumping off or tilting of the closure is still possible.
GB-A-2 063 226 discloses a snap-on closure having a non-
circular cross section. The closure is held on a container
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mouth by two ribs projecting inwardly from the inner surface.
The problem of the closure getting tilted or jumping off
during application is not addressed in GB-A-2 063 226.
AU-A-519 377 discloses a closure which engages with two
projections underneath two projections of a container mouth.
The two projections of the container engage at the same time
with the projections of the closure cap. The problem of the
closure getting tilted or jumping off during application is
not addressed and solved here.
The purpose of the invention is to avoid the drawbacks of the
state of the art, and in particular, therefore, to create a
container closure and/or a container wherein jumping off or
tilting of container closures in bottling plants is reliably
prevented. The closures and containers according to the
invention shall, in addition, be usable in state-of-the-art
bottling plants without problems, and producible in an effi-
cient and economic way.
According to the invention, these purposes are fulfilled with
a container closure, a container mouth and a combination of a
container closure and a container mouth according to the
features of the characterizing portion of the independent
patent claims.
A closure for a container possesses a closure base and a
closure jacket. Retaining elements are provided on the inside
of the closure jacket, said retaining elements being able to
be brought into engagement with retaining elements on the
container mouth on closure of the container by means of said
closure. The retaining elements can be threads (preferably
multi-start) or retaining beads of a snap closure.
In order that, in a bottling plant, the closure does not jump
off the container mouth or tilt in relation to the container
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mouth prior to definitive screwing or snapping on, in addi-
tion the closure jacket possesses auxiliary retaining
elements, said auxiliary retaining elements being able to be
brought into engagement with the container mouth. Preferably
the retaining elements in the mouth area of the container are
employed as a holding means - it is, however, also conceiv-
able to provide additional holding means adjacent to the
retaining elements on the container mouth, or to press the
closure onto the container mouth with the aid of the auxili-
ary retaining elements while relying on straightforward
friction.
The auxiliary retaining elements can, during placement of the
closure onto the container, be brought into engagement with
the container neck and/or its holding means, before the
retaining elements of the closure come into engagement with
the retaining elements of the container mouth. The auxiliary
retaining elements and the retaining elements each possess a
mechanical stop, said mechanical stop being able to be
brought into contact with a surface of the retaining elements
of the container mouth. As a result, the closure is
restricted in both axial directions in an initial intermedi-
ate position on the container mouth. At the same time, it is
essential that the auxiliary retaining means are constructed
in such a way that the force required for their placement is
less than the force required during actual closing. If the
closure is subsequently screwed on, a pressing force acting
on a closure is required to place it by means of the auxili-
ary retaining elements, and a torque is required for screwing
on. With this construction, the closure is placed onto the
container mouth without a large exertion of force, and is
held on said container mouth before the actual closure
sequence (snapping on or screwing on) occurs. A construction
with such auxiliary retaining elements is mainly of advantage
in the case of plastic closures with an elastic wall. The
auxiliary retaining elements are snapped onto the mouth by
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means of elastic deformation of the cap wall and/or by means
of their own inherent elastic deformation.
The mechanical stop of the auxiliary retaining means is
arranged on its side oriented towards the cap base, while the
mechanical stop of the retaining means is arranged on its
side oriented away from the cap base. In the intermediate
position, the container mouth retaining elements lie between
both mechanical stops, by which means the closure position is
restricted on both sides in the axial direction.
A particularly effective mechanical stop for the auxiliary
retaining elements is attained if the auxiliary retaining
elements are formed as an accumulation of material on the
inside of the closure jacket. By means of an accumulation of
material, a mechanical stop is formed which, in contrast to
flexible clips, effectively resists jumping-off of the clo-
sure in the intermediate position.
A particularly advantageous application of the retaining
elements will result in combination with snap closures. Such
snap closures possess a bead running around the inside of the
closure jacket, approximately parallel to the closure base.
The bead serving as a retaining element is, on closure of the
container, snapped over a correspondingly shaped bead on the
mouth of the container. Thanks to the auxiliary retaining
elements, the snap closure can, relying on a slight fric-
tional connection, be placed upon the retaining bead of the
container mouth prior to actual snapping-on. As a result,
jumping off or tilting of the closure is reliably avoided.
Auxiliary retaining means are similarly advantageous in
combination with multi-start threads as retaining elements.
The screw closure equipped with auxiliary retaining elements
is, in an initial step, snapped onto the multi-start thread
and as a result positioned exactly in relation to said
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thread. Subsequently, the screw closure can be screwed on or,
in the case of a snap-on and unscrewable closure, snapped on.
The mechanical stop of the multi-start thread is formed by
the thread start on the side of the thread oriented away from
the cap base.
When using snap closures with a retaining bead, said retain-
ing bead preferably possesses interruptions. These interrup-
tions increase the flexibility of the closure jacket and thus
facilitate the placement sequence.
A particulary simple embodiment will result if, as auxiliary
retaining elements, protrusions are used that project
radially inwards from the inside of the closure jacket. These
protrusions can be brought into engagement with the retaining
elements on the container mouth, wherein said retaining
elements fulfil the function of the previously described
holding means. The protrusions must be dimensioned in such a
way that the force required to overcome the auxiliary retain-
ing means is less than the force for actual closure. This
can, for example, occur through the auxiliary retaining
elements defining a greater inside diameter than the retain-
ing elements. A similar result is attained with protrusions
that extend over a small angular area only. Apart from that,
it is conceivable to form the protrusions sufficiently thinly
so that they can snap flexibly over the retaining bead on the
container mouth.
A particularly favourable embodiment will result if the
retaining bead of a snap closure possesses interruptions,
wherein an auxiliary retaining element in the form of a
projecting protrusion is in each case is provided flush with
one of these recesses. In order that the protrusions come
into engagement with the retaining elements on the container
mouth before the retaining bead, the protrusions must be
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arranged between the retaining bead and the free end of the
closure jacket. Preferably, the auxiliary retaining elements
are arranged adjacent to the free edge of the closure jacket.
As a result, a construction of the closure will result which
is economic in terms of the amount of material used.
In order to reliably avoid tilting of the closure prior to
the actual placement sequence, the auxiliary retaining
elements are preferably arranged axisymmetrically around the
circumference of the closure jacket, wherein at least two and
preferably approximately four to six auxiliary retaining
elements in the form of protrusions are used.
Similar advantageous embodiments result in combination with a
screw closure.
From the manufacturing point of view, auxiliary retaining
elements are simplest which are provided in the same way as
the retaining elements on the inside of the closure jacket
and which coordinate with the retaining elements of a con-
tainer. It is also conceivable, however, to achieve the same
result with other auxiliary retaining elements, said retain-
ing elements being able to be brought into engagement with
specially provided holding means on the container mouth.
Thus, for example, closures with an inner seal can be pro-
vided with retaining elements on said inner seal, said
elements being able to be brought into engagement with hold-
ing means on the inside of the container mouth.
A similar behaviour during the placement sequence can also be
attained if, in place of auxiliary retaining means on the
closure, auxiliary retaining means are provided in the area
of a container mouth. Here, similar embodiments to those
described in the above will lead to particularly advantageous
results. The auxiliary retaining elements can be formed as
protrusions projecting from the outside surface of the con-
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tainer mouth. The protrusions are arranged between the edge
of the container mouth and the retaining elements of the
container mouth (i.e. between a retaining bead or the upper
side of a thread and the edge of the container mouth). In
order that the force required to place the auxiliary retain-
ing element is less than the closure force, respectively the
closure torque, the auxiliary retaining elements (in the
preferred embodiment the outwardly projecting protrusions)
must be specially dimensioned. A simple design will result if
the protrusions define an outside diameter on the container
mouth that is less than the outside diameter as defined by
the retaining elements of the container.
The mechanical stop of the auxiliary retaining elements of
the container mouth is in this case arranged on the side of
the protrusions oriented away from the container opening. The
mechanical stop of the retaining elements of the container
mouth is formed by the side of retaining elements oriented
towards the container opening.
The magnitude of the frictional connection can, apart from
that, also be be defined by the angular range over which the
auxiliary retaining elements, i.e. the protrusions, extend.
The smaller the segments are kept, the less will be the
press-on force required.
Because of the generally high material strength of the con-
tainer mouth in comparison to the closure, the retaining bead
is preferably formed circumferentially. The arrangement of
recesses (as in the case of the closure) would, apart from
bringing savings in material, be of little advantage. With a
continuous circumferential retaining bead, the auxiliary
retaining elements (protrusions) can for this reason be
arranged in any desired way in relation to the container.
However, also in this case, an arrangement of at least two
and preferably four to six protrusions is recommended, pre-
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ferably arranged axisymmetrically to the axis of the con-
tainer.
A basic consideration of the invention is therefore that,
disregarding the retaining elements on a closure and a con-
tainer mouth which permit fixing of the closure on said
container mouth, auxiliary retaining elements are arranged on
the closure and/or the container mouth, said auxiliary
retaining elements being able to be brought into engagement
with holding means on the container mouth and/or the closure.
With that, the auxiliary retaining elements must, at an
intermediate position, come into engagement with the holding
means before the retaining elements of the closure and of the
container mouth come into mutual engagement. The retaining
elements and the auxiliary retaining elements each possess a
mechanical stop which, in this intermediate position, holds
the closure fast on the container mouth in both axial direc-
tions. In the intermediate position, both mechanical stops
lie on both sides of the holding means and thus restrict the
axial movement of the closure. The engagement of the auxili-
ary retaining elements should, apart from that, with advan-
tage be so designed that the force required for placement is
less than the closure force, respectively the closure torque.
With a method for closing a container mouth with a closure,
the closure is placed on the container mouth in a first step,
and held on said container mouth in an intermediate position.
An initial press-on force is used to fix the closure in this
intermediate position.
In the intermediate position, the position of the closure is
restricted in both axial directions.
In a second step of the method, the closure is pressed into a
second, sealing position with a second press-on force (or
screw-on torque). The initial press-on force is selected to
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be less than the second press-on force. As a result of the
closure already being held firmly on the container mouth in
the intermediate position, jumping off or tilting of the
closure prior to applying the second press-on force is
reliably prevented.
The invention is more closely explained in the following,
with the aid of the drawings and in various embodiments:
namely,
Figure 1 a closure according to the invention which is
held with the auxiliary retaining elements in an
intermediate position on a container (in cross
section),
Figure 2 a closure according to figure 1 which, in a
sealing position, is placed firmly on a con-
tainer,
Figure 3 a view from below of a closure according to the
invention,
Figure 4 a cross section of a container mouth according
to the invention with a closure placed upon said
container mouth in the intermediate position,
Figure 5 a plan view of a container mouth according to
the invention, and
Figure 6 a modified embodiment with a multi-start thread.
Figure 1 shows a closure 1 according to the invention, said
closure placed in an intermediate position P1 on a container
mouth 8 of a container 2. The closure possesses a closure
base 3 and a closure jacket 4 extending downwards and
attached to said base. Retaining elements 6 are provided on
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the inside of the closure jacket 4, said retaining elements
being able to be brought into engagement with retaining
elements 7 on the outside of the container mouth 8. The
retaining elements 6 on the inside 5 of the closure jacket 4
are formed by a circumferential bead running approximately
parallel to the closure cap 3. The bead is interrupted by
individual interruptions 17 that increase the flexibility of
the cap wall 4. The retaining elements 7 of the container
mouth 8 are likewise formed by a circumferential bead on the
outside of the container mouth 8.
The closure 1 possesses auxiliary retaining elements 10 on
the inside which likewise can be brought into engagement with
the retaining elements 7 on the container mouth 8. The aux-
iliary retaining means 10 are formed as protrusions project-
ing radially inwards on the inside 5 of the closure jacket 4.
The auxiliary retaining elements possess a mechanical stop 13
arranged on their side oriented towards the cap base 3. The
retaining elements 6 possess a mechanical stop 14 on their
side oriented away from the cap base 3. The retaining
elements 7 of the container mouth 8 lie in the intermediate
position Pl between both the contact surfaces 13, 14 of the
auxiliary retaining elements 10 and the retaining elements 6.
The protrusions are formed to be solid, so that the mechan-
ical stop 13 enables reliable axial holding of the closure on
the container mouth. In figure 1, the closure 1 is held by
the auxiliary retaining elements 10 in the intermediate
position Pl on the container mouth 8. The auxiliary retaining
elements 10, in other words the inwardly projecting protru-
sions, are arranged adjacent to the lower edge of the closure
1 so that, on placement of the closure 1 onto a container
mouth, they come into engagement with the retaining elements
7 of the container mouth 8 before the retaining elements 6.
The auxiliary retaining elements 10 define a free inside
diameter that is greater than the free inside diameter as
defined by the retaining elements 6. The force required to
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place the auxiliary retaining elements 10 is therefore less
than the actual closure force.
Figure 2 shows the closure from figure 1 which is completely
placed upon a container mouth 8 in a sealing position P2.
Because the retaining elements 6 of the closure 1 define a
smaller free inside diameter than the auxiliary retaining
elements 10, the closure 1 in the position shown in figure 2
is held more firmly on the container mouth 8 than the posi-
tion shown in figure 1. The position in figure 1 serves only
to temporarily hold the closure on the container mouth 8 so
that jumping off or tilting is avoided. In the position shown
in figure 1, however, the container is not closed to form a
seal.
The mechanical stop 13 of the auxiliary retaining elements 10
is no longer required in the sealing position P2. It is
naturally conceivable, with the closure, to briefly reclose
containers that have already been opened by using only a
small press-on force in order to once again bring the closure
into the intermediate position. In this case, a sealing
reclosure is not possible, but the container mouth can be
protected from contamination or the intrusion of insects.
Figure 3 shows a view from beneath of the closure shown in
figures 1 and 2. Retaining elements 6 are provided in the
form of a circumferential bead on the inside 5 of the closure
jacket 4. The bead is interrupted by five interruptions 17,
by which means the flexibility and elasticity of the closure
jacket 4 is increased. An auxiliary retaining element 10 in
the form of an inwardly projecting protrusion is provided in
each of the interruptions 17. The auxiliary retaining
elements 10 are dimensioned in such a way that the free
inside diameter that they define is greater than the free
inside diameter defined by the retaining elements 6. The five
auxiliary retaining elements 10 are (in the same way as the
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interruptions 17) distributed around the closure jacket 4
axisymmetrically to the axis of the closure.
Figure 4 shows a further embodiment with the features of the
invention. A container mouth that can be closed with a con-
ventional snap closure possesses auxiliary retaining elements
30 on its upper edge 21. On placement of a conventional snap
closure, without great exertion of force, the closure can be
brought with its retaining elements 6 into engagement with
the auxiliary retaining elements 30 of the container mouth 8.
The auxiliary retaining elements 30 are formed as radially
outwardly projecting protrusions, the outside diameter of
which is less than the outside diameter as defined by the
retaining elements 7 of the container mouth 8. The auxiliary
retaining elements 30 possess a mechanical stop 34 arranged
on their side oriented away from the container opening. A
circumferential bead is used as retaining elements 7, said
bead possessing a mechanical stop 33 on its side oriented
toward the container opening. The auxiliary retaining
elements 30 are provided between the retaining elements 7 and
the upper edge 21 of the container mouth 8.
Similar to a closure according to the invention, with a
container mouth 8 according to the invention an axi-
symmetrical arangement of the auxiliary retaining elements 30
is also advantageous. Figure 5 shows a container mouth 8 in
plan view, wherein four auxiliary retaining elements 30 in
the form of outwardly projecting protrusions are arranged
axisymmetrically. The auxiliary retaining elements 30 define
a smaller outside diameter than the retaining elements 7.
Figure 6 shows a further embodiment of a closure according to
the invention on a container mouth 8. In place of a snap
closure, a closure with a multi-start thread is shown here.
The closure 1 possesses an auxiliary retaining element 10 on
its lower edge, said auxiliary retaining element coming into
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engagement with the threads 36 of the container mouth 8
before the threads 16 of the closure come into engagement
with the threads 36 of the container mouth 8. On placement of
the closure 1 onto the container mouth, the auxiliary retain-
ing elements 10 first come into engagement with the uppermost
section of the threads 36 and are held with a comparatively
slight frictional connection on the container mouth 8.
Subsequently, the closure 1 can be screwed on firmly with
conventional screw-on heads, or pressed on in the case of a
closure capable of snapping on and unscrewing.
Naturally, in the case of closures with threads, an embodi-
ment is conceivable which possesses auxiliary retaining
elements on the container mouth 8.
Inasmuch as the invention is subject to modifications and
variations, the foregoing description and accompanying draw-
ings should not be regarded as limiting the invention, which
is defined by the following claims and various combinations
thereof:
