U.S. patent application number 15/414205 was filed with the patent office on 2017-07-13 for container and closure.
The applicant listed for this patent is Threadless Closures Limited. Invention is credited to Anthony Henry Joseph Fraser, John Hein.
Application Number | 20170197764 15/414205 |
Document ID | / |
Family ID | 59274771 |
Filed Date | 2017-07-13 |
United States Patent
Application |
20170197764 |
Kind Code |
A1 |
Hein; John ; et al. |
July 13, 2017 |
Container And Closure
Abstract
A container and closure includes a closure secured to the
container through projections comprising a series of horizontal,
circumferentially spaced apart elements arranged so that the
elements on the closure can pass though the spaces between the
elements on the container and locate beneath them to secure the
closure to the container. The elements of the projection on the
container are separated from each other in the circumferential
direction and do not overlap with each other in the vertical
direction and the elements of the projection on the closure are
separated from each other in the circumferential direction and do
not overlap with each other in the vertical direction. The closure
carries a sealing member for providing a seal with either an
internal or external sealing surface of the container. The seal is
driven down from a lead-in surface to engage the sealing surface as
the closure is rotated.
Inventors: |
Hein; John; (Leeds, GB)
; Fraser; Anthony Henry Joseph; (Rutland, GB) |
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Applicant: |
Name |
City |
State |
Country |
Type |
Threadless Closures Limited |
Rutland |
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GB |
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Family ID: |
59274771 |
Appl. No.: |
15/414205 |
Filed: |
January 24, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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PCT/GB2015/052154 |
Jul 24, 2015 |
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15414205 |
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PCT/GB2016/052215 |
Jul 21, 2016 |
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PCT/GB2015/052154 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B65D 51/1688 20130101;
B65D 41/065 20130101; B65D 85/72 20130101 |
International
Class: |
B65D 43/02 20060101
B65D043/02; B65D 85/72 20060101 B65D085/72; B65D 1/02 20060101
B65D001/02; B65D 43/14 20060101 B65D043/14; B65D 51/16 20060101
B65D051/16; B65D 1/16 20060101 B65D001/16 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 25, 2014 |
GB |
1413249.2 |
Mar 2, 2015 |
GB |
1503512.4 |
Oct 23, 2015 |
GB |
1518819.6 |
Dec 21, 2015 |
GB |
1522544.4 |
Jan 27, 2016 |
GB |
1601501.8 |
Claims
1. A container and a closure therefor, the container having an
opening defining an axis and an outwardly projecting first member
around an external surface of the container, said first member
comprising a plurality of circumferentially spaced apart first
portions, each first portion having an element with elongate upper
and lower surfaces, said upper and lower surfaces thereof being
substantially horizontal in the circumferential direction, the
closure having a top part and a skirt part, the skirt part
comprising an inwardly projecting second member around an internal
surface thereof, said second member comprising a plurality of
circumferentially spaced apart second portions, each second portion
having an element with elongate upper and lower surfaces, said
upper and lower surfaces thereof being substantially horizontal in
the circumferential direction, said elements of the second portions
being of a length such that they can pass through spaces between
the first portions and being locatable beneath the first portions
so as to secure the closure to the container.
2. A container and a closure as claimed in claim 1, in which each
of the first portions, or each of the second portions, has an
upwardly inclined end at one end thereof and/or a downwardly
inclined end at the other end thereof.
3. A container and a closure as claimed in claim 2, in which the
upwardly and/or downwardly inclined ends of the second portions
extend beyond said elongate upper and lower surfaces thereof,
respectively.
4. A container and a closure as claimed in claim 2 in which upon
rotation of the closure in a first direction about axis A, said
downwardly inclined ends acts to drive the second portions
downwards relative to the first portions.
5. A container and a closure as claimed in claim 2 in which upon
rotation of the closure in a second direction about axis A, said
upwardly inclined ends acts to drive the second portions upwards
relative to the first portions.
6. A container and a metal closure as claimed in claim 1 in which
the closure has a sealing member for providing a seal with a
sealing surface of the container, the sealing surface being a
substantially vertical surface about the interior or exterior of a
neck portion of the container.
7. A container and closure as claimed in claim 3 in which said
downwardly inclined ends act to drive the second portions downwards
from a position in which said sealing member contacts the container
in a non-sealing position to a position in which said sealing
member sealingly engages the sealing surface of the container.
8. A container and closure as claimed in claim 7 in which the
sealing member comprises an o-ring mounted in a gland.
9. A container and closure as claimed in claim 1 in which the
closure is movable between a first secured sealed position and a
second secured venting position in which venting of the container
is enabled.
10. A container and closure as claimed in claim 9 in which the
skirt portion of the closure comprises a further inwardly
projecting member comprising a plurality of circumferentially
spaced apart third portions each of the third portions having an
upper surface which is at a lower level than said upper surfaces of
the second portions, said third portions being arranged to engage
the lower surfaces of the first portions when the closure is in a
venting position.
11. A container and a closure therefor, the container having an
opening defining an axis and an outwardly projecting first member
around an external surface of the container, said first member
comprising a plurality of circumferentially spaced apart first
portions, each first portion comprising an element having an upper
surface and a lower surface, said upper surface being substantially
horizontal in the circumferential direction and said lower surface
being substantially horizontal in the circumferential direction,
the closure having a top part and a skirt part, and a sealing
member for providing a seal with a sealing surface of the
container, the skirt part comprising an inwardly projecting second
member around an internal surface thereof, said second member
comprising a plurality of circumferentially spaced apart second
portions, the closure being securable to the container by
interaction between said first and second portions, the closure
being movable between a first position in which at least part of
said second portions engage the upper surfaces of said first
portions, a second position, following rotation in a first
direction and downward movement of the closure relative to the
container, in which said sealing member contacts the container in a
non-sealing position and elements of said second portions are
aligned with spaces between said first portions and a third
position, following further rotation of the closure in the first
direction relative to the container and further downward movement
of the closure relative to the container, in which said sealing
member has been moved downwards to sealingly engage said sealing
surface and said elements of said second portions are located
beneath said first portions in contact with said lower surfaces
thereof.
12. A container and closure as claimed in claim 11 in which the
skirt portion of the closure comprises a further inwardly
projecting member comprising a plurality of circumferentially
spaced apart third portions each of the third portions having an
upper surface which is at a lower level than said upper surfaces of
the second portions, said third portions being arranged to engage
the lower surfaces of the first portions when the closure is in
said second position.
13. A closure and container as claimed in claim 1 comprising a
widemouth container as defined herein.
14. A container and closure as claimed in claim 11 in which said
sealing member is compressed in a substantially horizontal
direction between the container and the closure as the closure is
moved downwards by rotation thereof to move it into sealing
engagement with said sealing surface.
15. A container and closure as claimed in claim 1 in which the
metal closure is formed from sheet metal and shaped by forming
processes.
16. A container and metal closure as claimed in claim 15 in which
the first member and/or the second member is formed by an
indentation in the external surface of the skirt portion of the
closure so as to form said spaced apart first portions and/or said
spaced apart second portions projecting from an inner surface of
the skirt portion.
17. A container and closure as claimed in claim 15 in which the
closure comprising two, initially separate, components: an annular
skirt portion adapted to be releasably secured to the container and
a closing portion which has been irreversibly secured to the skirt
portion so as to close an opening therein, preferably by a seamed
joint.
18. A container and closure as claimed in claim 11 in which the
container comprising a container body having a first opening at a
first end thereof and a second opening at a second end thereof, the
closure being releasably mounted on the container body so as to
releasably close the first opening, and the second opening of the
container body being closed by a container closing portion which
has been irreversibly secured to the container body to close
permanently the second end thereof, preferably by a seamed
joint.
19. A container and metal closure as claimed in claim 1 in which
the container comprises a container body with said opening at one
end thereof and a base portion closing the other end thereof, said
first member being provided on an external surface of a neck
portion of the container, said neck portion being an integral part
of the container body and being at or towards an upper end
thereof.
20. A plastic container and a metal closure therefor, the container
having an opening defining an axis and first engagement means for
releasably securing the metal closure thereto so as to releasably
close said opening, the closure having a sealing member for
providing a seal with a sealing surface of the container, the
sealing member comprising an o-ring provided within a recess in the
closure and the sealing surface being an external surface of the
container, said recess and sealing surface together defining a
gland in which the o-ring is located.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of
PCT/GB2015/052154, filed on Jul. 24, 2015, which claims the
priority benefit of Great Britain Patent Application No.
GB1413249.2 filed on Jul. 25, 2014 and Great Britain Patent
Application No. GB1503512.4 filed on Mar. 2, 2015, and is also a
continuation-in-part of PCT/GB2016/052215 filed Jul. 21, 2016,
which claims the priority benefit of Great Britain Patent
Application No. GB1518819.6 filed on Oct. 23, 2015, Great Britain
Patent Application No. GB1522544.4 filed on Dec. 21, 2015, Great
Britain Patent Application No. GB1601501.8 filed on Jan. 27, 2016,
and PCT/GB2015/052154, filed on Jul. 24, 2015, which claims the
priority benefit of Great Britain Patent Application No.
GB1413249.2 filed on Jul. 25, 2014 and Great Britain Patent
Application No. GB1503512.4 filed on Mar. 2, 2015. The contents of
each of these applications are hereby incorporated by reference as
if fully set forth herein in their entirety.
FIELD OF THE INVENTION
[0002] This invention relates to a container and closure, in
particular a container for housing a beverage. The container may be
of a variety of sizes and may, for example, be a wide-mouth
container or it may be a bottle. In some cases, it may be designed
for containing a carbonated beverage. The invention also relates to
the container and closure separately and together and a method of
use of the container and closure.
BACKGROUND ART
[0003] Containers and closures for wide-mouth containers and
bottles are known such as those described in the applicants earlier
applications, for example WO2006/000774 and WO2011/151630. A
further development is disclosed in WO2014/006418. These seek to
provide a closure capable of securely closing a container the
contents of which may be at an elevated pressure, eg during
transportation and/or when subject to elevated temperatures, whilst
remaining relatively easy for a consumer to remove.
[0004] A wide-mouth container can be used both to store a beverage
(or other contents) and as a drinking vessel once the closure has
been removed. In some cases, the closure may also be designed so it
can be used to re-close and/or re-seal the container. A typical
wide-mouth container has a mouth with a diameter in the range 55 to
65 mm although the term also applies to containers having a mouth
with a diameter in the range 45 to 80 mm.
[0005] A bottle is typically used to store a beverage (or other
contents) prior to pouring it into a drinking vessel. Commonly used
bottles, such as those used to store beer and other beverages,
typically have a mouth with a diameter of around 28 mm.
[0006] Whilst the closures described in the above documents are
satisfactory in many cases, the present invention seeks to provide
improvements which enable the container and/or the closure to be
further simplified, and to reduce the cost of materials and/or the
cost of manufacture whilst maintaining the performance of the
closure, in particular the ease and reliability of opening and
closure, re-closure (if required) and venting (if housing a
carbonated beverage).
SUMMARY OF INVENTION
[0007] A container and a closure therefor, the container having an
opening defining an axis and an outwardly projecting first member
around an external surface of the container, said first member
comprising a plurality of circumferentially spaced apart first
portions, each first portion having an element with elongate upper
and lower surfaces, said upper and lower surfaces thereof being
substantially horizontal in the circumferential direction, the
closure having a top part and a skirt part, the skirt part
comprising an inwardly projecting second member around an internal
surface thereof, said second member comprising a plurality of
circumferentially spaced apart second portions, each second portion
having an element with elongate upper and lower surfaces, said
upper and lower surfaces thereof being substantially horizontal in
the circumferential direction, said elements of the second portions
being of a length such that they can pass through spaces between
the first portions and being locatable beneath the first portions
so as to secure the closure to the container.
[0008] The means for securing the closure to the container thus
comprises a projection extending around the circumference of each
part comprising a series of substantially horizontal,
circumferentially spaced apart elements arranged such that the
elements on the closure can pass though the spaces between the
elements on the container and located beneath them to secure the
closure to the container. The elements of the projection on the
container are separated from each other in the circumferential
direction and do not overlap with each other in the vertical
direction. Similarly, the elements of the projection on the closure
are separated from each other in the circumferential direction and
do not overlap with each other in the vertical direction.
[0009] In a preferred arrangement, each of the first portions, or
each of the second portions, has an upwardly inclined end at one
end thereof and/or a downwardly inclined end at the other end
thereof.
[0010] In a preferred arrangement, the upwardly and/or downwardly
inclined ends of the second portions extend beyond said elongate
upper and lower surfaces thereof, respectively.
[0011] In a preferred arrangement, upon rotation of the closure in
a first direction about axis A, said downwardly inclined ends acts
to drive the second portions downwards relative to the first
portions.
[0012] In a preferred arrangement, upon rotation of the closure in
a second direction about axis A, said upwardly inclined ends acts
to drive the second portions upwards relative to the first
portions.
[0013] The closure preferably has a sealing member for providing a
seal with a sealing surface of the container, the sealing surface
preferably being a substantially vertical surface about the
interior or exterior of a neck portion of the container. In a
preferred arrangement, the sealing member comprises an o-ring
provided within a recess in the closure and the sealing surface is
an internal or external surface of a neck portion of the container,
said recess and sealing surface together defining a gland in which
the o-ring is located.
[0014] Said top part of the closure may have a bore component for
extending into the container opening and a sealing member on the
bore component for providing a seal with an internal sealing
surface of the container. Alternatively, the sealing member may be
provided on the interior of the skirt portion of the closure for
providing a seal with an external sealing surface of the
container.
[0015] Preferably, said downwardly inclined ends act to drive the
second portions downwards from a position in which said sealing
member contacts the container in a non-sealing position to a
position in which said sealing member sealingly engages the
internal or external sealing surface of the container.
[0016] In a preferred arrangement, the closure is movable between a
first secured sealed position and a second secured venting position
in which venting of the container is enabled.
[0017] In a preferred arrangement, the skirt portion of the closure
comprises a further inwardly projecting member comprising a
plurality of circumferentially spaced apart third portions each of
the third portions having an upper surface which is at a lower
level than said upper surfaces of the second portions, said third
portions being arranged to engage the lower surfaces of the first
portions when the closure is in a venting position.
[0018] According to another aspect of the invention, there is
provided, a container and a closure therefor, the container having
an opening defining an axis and an outwardly projecting first
member around an external surface of the container, said first
member comprising a plurality of circumferentially spaced apart
first portions, each first portion comprising an element having an
upper surface and a lower surface, said upper surface being
substantially horizontal in the circumferential direction and said
lower surface being substantially horizontal in the circumferential
direction, the closure having a top part and a skirt part, and a
sealing member for providing a seal with a sealing surface of the
container, the skirt part comprising an inwardly projecting second
member around an internal surface thereof, said second member
comprising a plurality of circumferentially spaced apart second
portions, the closure being securable to the container by
interaction between said first and second portions, the closure
being movable between a first position in which at least part of
said second portions engage the upper surfaces of said first
portions, a second position, following rotation in a first
direction and downward movement of the closure relative to the
container, in which said sealing member contacts the container in a
non-sealing position and elements of said second portions are
aligned with spaces between said first portions and a third
position, following further rotation of the closure in the first
direction relative to the container and further downward movement
of the closure relative to the container, in which said sealing
member has been moved downwards to sealingly engage said sealing
surface and said elements of said second portions are located
beneath said first portions in contact with said lower surfaces
thereof.
[0019] Such a closure and container can be arranged so that when
the closure is initially placed on the container, it sits
horizontally thereon with the second member resting on the first
member. Following horizontal rotation of the closure, it moves to a
position in which the sealing member rests on the mouth of the
container. Further horizontal rotation results in the closure being
driven downwards so the sealing member is moved downwards to a
sealing position and the second member located beneath the first
member to secure the closure to the container.
[0020] As above, the first portions of the first member on the
container are separated from each other in the circumferential
direction and do not overlap with each other in the vertical
direction. Similarly, the second portions of the second member on
the closure are separated from each other in the circumferential
direction and do not overlap with each other in the vertical
direction.
[0021] Said sealing surface is preferably substantially parallel to
said axis and the container has an inclined lead-in surface at the
upper end thereof leading to said sealing surface.
[0022] Preferably, in said second position, the sealing member
contacts said lead-in surface.
[0023] Preferably, said sealing member is compressed between the
container and the closure is moved downwards from said second
position to said third position to move it into sealing engagement
with said sealing surface.
[0024] The closure is preferably arranged to be removed from the
container by rotation about the axis in a second direction so as to
move it from said third position to said second position and then
to said first position.
[0025] In a preferred arrangement, the skirt portion of the closure
comprises a further inwardly projecting member comprising a
plurality of circumferentially spaced apart third portions each of
the third portions having an upper surface which is at a lower
level than said upper surfaces of the second portions, said third
portions being arranged to engage the lower surfaces of the first
portions when the closure is in said second position.
[0026] In a preferred arrangement, each of said second portions has
a downwardly angled end arranged to engage a first end face of the
first portions, or vice versa, and interact therewith so as to
drive the closure downwards as the closure is rotated in the first
direction from said second position.
[0027] In a preferred arrangement, each of said second portions has
an upwardly angled end arranged to engage a second end face of the
first portions, or vice versa, and interact therewith so as to
drive the closure upwards as the closure is rotated in a second
direction (opposite to the first direction) from said second
position.
[0028] Said elements of the second portions may be arranged to be
pass angularly through spaces between the first portions.
[0029] The circumferential length of the substantially horizontal
upper surfaces of the second portions is preferably at least 50%,
and preferably at least 75%, of the circumferential length of the
substantially horizontal lower surfaces of the first portions.
[0030] The circumferential length of the substantially horizontal
upper surfaces of the second portions is preferably substantially
the same as the circumferential length of the substantially
horizontal lower surfaces of the first portions.
[0031] Each first portion preferably has a circumferential length
substantially similar to the circumferential length of said
elements of the second portions.
[0032] Said elements of the second portions are in preferably in
contact with substantially the entire circumferential length of
said lower surfaces of said first portions when the closure is
secured to the container.
[0033] The combined circumferential lengths of the first portions
is preferably substantially half the outer circumference of the
container at the position at which the first portions are provided
thereon.
[0034] Said first member may be spaced from the upper end of the
container, preferably by a distance in the range 6 to 15 mm and
most preferably 9 to 12 mm.
[0035] The closure and container described above may be a widemouth
container as defined herein.
[0036] In some embodiments, the container may be formed of a
non-metallic material, preferably a plastic material.
[0037] The container may be formed by an injection moulding process
followed by a blow moulding process of the parts beneath the first
member.
[0038] The container may have a groove in its external surface
beneath said first member, the first member and/or the groove
providing holding means by which the container can be held when
being transferred from injection moulding apparatus to blow
moulding apparatus and/or during said blow moulding process.
[0039] In other embodiments the container may be formed of metal or
another material.
[0040] The cross-sectional area of the o-ring is preferably smaller
than the cross-sectional area of the gland so, when the metal
closure is mounted on the container, the o-ring is able to move
and/or deform within the gland.
[0041] Said sealing surface is preferably substantially vertical
and downward movement of the closure relative to the container from
the second position to the third position compresses the o-ring in
a substantially horizontal direction into sealing engagement with
the sealing surface.
[0042] The recess preferably extends around a circumference of the
closure, the recess comprising a first side wall on one side of the
o-ring for constraining the o-ring when it is subject to a pressure
differential and a second side wall on the opposite side of the
o-ring for retaining the o-ring in the recess and a back wall
joining the first and second side walls.
[0043] The first side wall preferably extends in a radial direction
by a distance f (the distance f being at least 1/2 of the diameter
of the o-ring cross-section prior to compression of the o-ring)
from the back wall and the second side wall extends in a radial
direction by a distance s from the back wall, the distance s being
at least 1/2 of the distance f.
[0044] The distance s is preferably at least 1/3 of the diameter of
the circular cross-section of the o-ring prior to deformation of
this cross-section, and preferably 1/3-2/3 of said diameter.
[0045] The first side wall and/or the second side wall are
preferably substantially planar and lie substantially perpendicular
to said axis. And the back wall maybe substantially planar and
substantially parallel to said axis.
[0046] In some embodiments, said inclined surface may lead to an
internal sealing surface and said bore component comprises a
substantially frusto-conical portion which, when the closure is
mounted to the container, lies adjacent and substantially parallel
to said inclined surface. The closure is also preferably shaped to
minimise any space between the bore component and the interior of
the container in the region above the gland when the closure is
mounted on the container.
[0047] In a preferred arrangement, in said second position, the
sealing member contacts said inclined surface.
[0048] In a preferred arrangement, said sealing member is
compressed in a substantially horizontal direction between the
container and the closure as the metal closure is moved downwards
by rotation thereof to move it into sealing engagement with said
sealing surface.
[0049] In some embodiments, the closure may be formed of a plastic
material, eg by means of an injection moulding process.
[0050] In other embodiments, the closure is formed of metal, eg
from sheet metal, and may be shaped by forming processes. The first
member and/or the second member may, for example, be formed by an
indentation in the external surface of the skirt portion of the
closure so as to form said spaced apart first portions and/or said
spaced apart second portions projecting from an inner surface of
the skirt portion.
[0051] The third member may also be formed by an indentation in the
external surface of the skirt portion of the closure so as to form
said spaced apart third portions projecting from an inner surface
of the skirt portion.
[0052] Alternatively, the third member may be formed by curling
distal portions of the skirt portion radially inwards so as to form
said spaced apart third portions projecting from an inner surface
of the skirt portion.
[0053] In some embodiments, the top part and skirt part of the
closure may be formed of metal and the inwardly projecting second
member provided by a plastics component provided on an internal
surface of the skirt part.
[0054] In some arrangements, the metal closure may comprise two,
initially separate, components: an annular skirt portion adapted to
be releasably secured to the container and a closing portion which
has been irreversibly secured to the skirt portion so as to close
an opening therein, preferably by a seamed joint.
[0055] In a further arrangement, a metal container may comprise a
container body having a first opening at a first end thereof and a
second opening at a second end thereof, the metal closure being
releasably mounted on the container body so as to releasably close
the first opening, and the second opening of the container body
being closed by a container closing portion which has been
irreversibly secured to the container body to close permanently the
second end thereof, preferably by a seamed joint.
[0056] The container may comprise a container body with said
opening at one end thereof and a base portion closing the other end
thereof, said first member being provided on an external surface of
a neck portion of the container, said neck portion being an
integral part of the container body and being at or towards an
upper end thereof.
[0057] In a preferred arrangement, the second portions are provided
on the closure. And the second portions preferably comprise said
upwardly inclined end at one end thereof and said downwardly
inclined end at the other end thereof.
[0058] Said first portions may each comprise a substantially
horizontal upper surface and a substantially horizontal lower
surface, the upper and lower surfaces being joined by first and
second angled end surfaces, the first angled end surface being
arranged to engage and slide down said downwardly inclined surface
of the second portions when the closure is rotated in the closing
direction relative to the container and/or the second end surface
being arranged to engage and slide up said upwardly inclined
surface of the second portions when the closure is rotated in the
loosening direction relative to the container.
[0059] Rotation of the closure in the tightening direction
preferably moves the closure downwards relative to the container,
this downward movement of the closure causing compression of the
seal member in a substantially horizontal direction into sealing
engagement with said sealing surface.
[0060] As mentioned, in some embodiments, said sealing surface is
an external surface of the container neck and the o-ring seal is
mounted in a recess of the skirt portion of the closure.
[0061] According to a further aspect of the invention, there is
provided a plastic container and a metal closure therefor, the
container having an opening defining an axis and first engagement
means for releasably securing the metal closure thereto so as to
releasably close said opening, the closure having a sealing member
for providing a seal with a sealing surface of the container, the
sealing member comprising an o-ring provided within a recess in the
closure and the sealing surface being an external surface of the
container, said recess and sealing surface together defining a
gland in which the o-ring is located.
[0062] The cross-sectional area of the o-ring is preferably smaller
than the cross-sectional area of the gland so, when the metal
closure is mounted on the container, the o-ring is able to move
and/or deform within the gland.
[0063] Preferably, the metal closure is movable between a first
secured sealed position and a second secured venting position in
which venting of the container is enabled.
[0064] In the first secured position the o-ring preferably engages
an inclined surface of the container which leads to said sealing
surface, and in the second secured position, the o-ring sealingly
engages said sealing surface.
[0065] According to another aspect of the invention there is
provided a container for use with a closure for providing a
container and closure as described in any of the arrangements
described above. The container may be formed of metal or other
materials.
[0066] According to another aspect of the invention there is
provided a closure for use with a container for providing a
container and closure as described in any of the arrangements
described above. The closure may be formed of metal or other
materials.
[0067] According to another aspect of the invention there is
provided a method of using a container and closure as described
above for containing a carbonated beverage.
[0068] According to another aspect of the invention there is
provided a method of manufacturing a container for use in providing
a container and closure as described above, the method comprising
an injection moulding process followed by a blow moulding
process.
[0069] In such a method, the container may have a groove in its
external surface beneath said first member, the first member and/or
the groove being used as holding means by which the container can
be held when being transferred from injection moulding apparatus to
blow moulding apparatus and/or during said blow moulding
process.
[0070] The closure may be formed by an injection moulding process.
The closure may be formed from polyoxymethylene. In other
arrangements, the closure may be formed from sheet metal and by
forming operations.
[0071] As mentioned above, in some embodiments, the inner surface
of the container preferably comprises a frusto-conical lead-in
surface adjacent the mouth of the container, the surface of which
is inclined, eg by 10-30 degrees, to the axis of the container, and
typically has a vertical dimension of about 2 mm. The lead-in
surface preferably leads to a substantially parallel-sided
cylindrical surface, the surface of which lies substantially
parallel to said axis. The diameter of the cylindrical surface is
substantially the same as the smaller (lowermost) end of the
frusto-conical surface. For closures used with carbonated
beverages, the sealing member is arranged to engage and to provide
a liquid and air-tight seal between the closure and this
substantially cylindrical surface.
[0072] For embodiments in which the sealing surface is an external
surface of the container, a similar inclined lead-in surface is
provided but on the exterior of the mouth of the container.
[0073] In some cases, it may be desirable to provide a plurality of
spaced apart venting grooves in the lead-in surface to assist
venting of the container.
[0074] As indicated above, for carbonated applications, the closure
is preferably movable between a first secured position and a second
secured position in which venting of the container is enabled, the
second secured position being raised relative to the first
position.
[0075] As mentioned above, the sealing member is preferably an
o-ring seal. The term o-ring as used herein is to be understood to
include a toroid of elastomer material surrounding an open centre
having a circular cross-section (or other cross-sections). Such
o-rings are conventionally located in a gland (which may typically
be defined by a groove or by a recess having two or more faces).
The o-ring is preferably able to move or deform within the gland so
as to be able to seal more tightly with the sealing surface in
response to a pressure differential between the interior and
exterior of the container (as described in WO 2011/151630 referred
to above). Whilst o-rings of this form are preferred, the term is
also to be understood to cover other forms of seal which simulate
an o-ring and other forms of flexible seal material provided
between two relatively rigid components (of a different material to
the seal), eg formed by an over-moulding of resilient material,
said material being capable of providing a gas tight seal between
those components. The o-ring is preferably formed of nitrile
butadiene rubber (NBR). Further details are given in GB1407157.5
referred to above, which is hereby incorporated by reference for
its description.
[0076] Directional terms, such as upwards, downwards, upper and
lower, as used herein are to be understood to refer to refer to
directions relative to a container standing on a horizontal surface
with the axis A passing through its opening being substantially
vertical (unless the context clearly requires otherwise).
[0077] Preferred and optional features of the invention will be
apparent from the following description and the subsidiary claims
of the specification.
BRIEF DESCRIPTION OF THE DRAWINGS
[0078] Embodiments of the present invention will now be described,
merely by way of example, with reference to the accompanying
figures, in which:
[0079] FIGS. 1A and 1B show a perspective view from above and side
view of a container used in a first embodiment of the
invention;
[0080] FIGS. 2A and 2B show a perspective view from above and from
below of a closure used in the first embodiment of the
invention;
[0081] FIG. 3A shows the closure of FIGS. 1A and B as it is moved
into engagement with the container of FIGS. 1A and B and FIG. 3B
shows the closure when secured to the container;
[0082] FIGS. 4A and B to 6A and B show schematic and
cross-sectional views of a simplified version of the container and
closure shown in FIGS. 1A and B and 2A and B to illustrate the
principal stages of the process of securing the closure to the
container: FIGS. 4A and 4B relate to a pre-loading stage, FIGS. 5A
and 5B relate to a loading (or venting) position and FIGS. 6A and
6B relate to a sealed position;
[0083] FIGS. 7A and B to 12A and B illustrate a more detailed
sequence of steps by which the closure of FIGS. 2A and B is secured
to the container of FIGS. 1A and B and cross-sections showing the
relative positions of the closure and container at each stage:
[0084] FIGS. 7A and 7B relate to a first pre-load stage;
[0085] FIGS. 8A and 8B relate to a second pre-load stage;
[0086] FIG. 9 relates to an initial load stage;
[0087] FIGS. 10A and 10B relate to an initial drive down stage;
[0088] FIG. 11 relates to a sealed position; and
[0089] FIGS. 12A and 12B relate to a locked position.
[0090] FIGS. 13 to 15A and B illustrate a sequence of steps by
which the closure is removed from the container and a cross-section
showing the relative positions of the closure and container at a
venting stage:
[0091] FIG. 13 relates to an initial removal stage;
[0092] FIG. 14 relates to a driving off stage;
[0093] FIGS. 15A and 15B relate to a venting stage;
[0094] FIGS. 16, 17 and 18 relate to further drive out stages;
[0095] FIGS. 19A and B to 21A and B show schematic and
cross-sectional views of a further simplified version of the
container and closure similar to those of FIGS. 4A and B to 6A and
B in relation to a container for a non-carbonated beverage: FIGS.
19A and 19B relate to a pre-loading stage, FIGS. 20A and 20B relate
to a loading position and FIGS. 21A and 21B related to a sealed
position;
[0096] FIG. 22 is a cross-section of another embodiment of a
closure according to the invention;
[0097] FIG. 23 is an enlarged portion of the closure of FIG. 22 to
illustrate a method of manufacture of such a closure;
[0098] FIGS. 24A and 24B are side views of part of a container
showing alternative details of the container compared to that shown
in FIG. 1B;
[0099] FIGS. 25A and 25B show cross-sectional views corresponding
to FIG. 22 of two further embodiments of a closure according to the
invention made of metal;
[0100] FIG. 26 shows a cross-sectional view of a metal container
for use with the closures of FIG. 25;
[0101] FIGS. 27A, 27B and 27C show a perspective view from above
and from below and a cross-sectional view of a metal closure used
in another embodiment of the invention;
[0102] FIGS. 28A and 28B are cross-sectional views showing the
metal closure of FIG. 27 when mounted on a container in a venting
position and a sealed position;
[0103] FIG. 29 shows a cross-sectional views of another embodiment
of a metal closure according to the invention;
[0104] FIGS. 30A and 30B are cross sectional views showing the
closure of FIG. 29 when mounted on a container in a venting
position and a sealed position;
[0105] FIGS. 31A and 31B are cross sectional views showing a
further embodiment of a metal closure and container on a container
in a venting position and a sealed position (in this case with an
external o-ring);
[0106] FIG. 32 is a perspective view of a skirt portion of a first
embodiment of a metal closure which is fabricated from two separate
parts;
[0107] FIG. 33 is a perspective view of an upper part of a
container adapted to receive a skirt portion such as that shown in
FIG. 32;
[0108] FIG. 34 is a cross-sectional view of the skirt portion of
FIG. 32 when releasably secured to a neck portion of the container
shown in FIG. 33;
[0109] FIG. 35 is a perspective view of a closing portion prior to
it being connected to the skirt portion of FIG. 32;
[0110] FIG. 36 is similar to FIG. 34 but also shows the closing
portion of FIG. 35 of the closure located over an opening of the
skirt portion;
[0111] FIG. 37 is similar to FIG. 36 showing the closing portion
once it has been irreversibly secured to the skirt portion to
complete the closure;
[0112] FIG. 38 is a perspective view of the closure and container
as shown in FIG. 36;
[0113] FIG. 39A is a cross-sectional view similar to that of FIG.
34 showing the skirt portion of a further embodiment secured to a
neck portion of a container, FIG. 39B is a similar view once the
top part of the closure has been secured to the skirt part and FIG.
39C shows the closure once it has moved from the sealed position in
FIG. 39B to a venting position;
[0114] FIG. 40 is an exploded perspective view showing a container
body, releasable closure and a container closing portion used to
close the base of the container body;
[0115] FIGS. 41A and 41B are perspective views of the exterior and
interior of the releasable closure shown in FIG. 40;
[0116] FIGS. 42A and 42B are detailed sectional views of the
releasable closure of FIG. 41 prior to and after being mounted to
the container body;
[0117] FIG. 43 is an enlarged sectional view of a seamed joint
between the container body and the container closing portion;
[0118] FIGS. 44A-44F show a further embodiment of the invention
similar to that shown in FIG. 31 but with six sets of projections
around the circumference of the container and the closure: FIG. 44A
is a perspective view of the closure mounted on the container,
FIGS. 44B and 44C show a perspective and partial front view of the
container, respectively, FIGS. 44D and 44E, are perspective views
from above and beneath the closure and FIG. 44F is a front view of
the closure;
[0119] FIGS. 45A-45C show another embodiment of the invention
similar to that shown in FIG. 44 but without a handling recess or
transfer feature on the container: FIG. 45A is a perspective view
of the closure mounted on the container, and FIGS. 45B and 45C show
a perspective and partial front view of the container,
respectively;
[0120] FIGS. 46A, 46B and 46C are schematic drawings illustrating
the shape of first and second portions designed for a negative
pressure application; and
[0121] FIG. 47 is a cross-sectional view of a further embodiment
similar to that of FIG. 41 in which the metal closure has features
formed of plastic on the internal surface thereof.
[0122] FIGS. 1A and 1B show a wide-mouth container 10 used in a
first embodiment of the invention. The container has an opening 10A
defining an axis A and has an outwardly projecting first member 11
around an external surface of the container 10, the first member
comprising a plurality of circumferentially spaced apart first
portions 11A (four in the example shown), each first portion 11A
has an upper surface 11B, a lower surface 11C, a first end surface
11D and a second end surface 11E. The upper surface 11B is
substantially horizontal in the circumferential direction but may
be curved or inclined in the radial direction. The lower surface
11C is also substantially horizontal in the circumferential
direction and, in the embodiment shown, is substantially
horizontal, and substantially flat, in the radial direction. The
shape and function of the end surfaces will be described further
below with reference to FIGS. 7-18.
[0123] The spaced apart portions of the first member 11 form an
intermittent, outwardly projecting lip which may be located at or
near the upper end of the container 10 or, as in the embodiment
shown, spaced from the upper end of the container 10, eg by a
distance in the range 9-12 mm. The first portions 11A are separated
from each other in the circumferential direction and do not overlap
with each other in the vertical direction.
[0124] The upper end of the container 10 has a lead-in surface 12
which is inclined to the axis A and leads to a substantially
parallel sided, cylindrical portion 13 of the internal surface of
the container 10 (see FIGS. 4A and B, 5A and B and 6A and B). The
lead-in surface preferably has substantially frusto-conical shape
and lies at an angle in the range 10 to 30 degrees to the axis A. A
plurality of venting grooves 14 or passages are preferably provided
at spaced apart positions around the circumference of the lead-in
surface to facilitate venting of the container (described further
below).
[0125] The container shown in FIGS. 1A and B also has a handling
groove 15 in the external surface thereof to facilitate handling of
the closure as it passes through automatic machinery, eg during
manufacture and subsequent processes such as washing, filling,
closing etc. In other embodiments (not shown), the handling groove
may not be required.
[0126] The container is typically formed of a plastics material, eg
polyethylene terephthalate (PET) and is typically formed in a
two-stage moulding process: forming a preform in a first injection
moulding stage which forms the features above the groove 15 and
then a second blow moulding stage in which the preform is blown to
form the container shape beneath the groove 15. The intermittent
lip 11 and/or groove may be used to hold the preform during the
blow moulding stage. The PET container is typically provided with a
barrier material, eg in the form of a thin coating of silica or
carbon or in the form of a laminated structure to improve its
resistance to gas permeability (particularly the ingress of oxygen
or the egress of carbon dioxide).
[0127] In some embodiments it may also be desirable to provide the
container a small projection (typically projecting outwardly by 1
mm or less), known as a transfer ring, to enable the container to
be lifted to move it from one place to another by machinery during
manufacture and/or on a filling and closing line. This may, for
example, comprise a small shoulder provided around the exterior of
the container (described further in relation to FIG. 31)
[0128] The container may also be formed of other materials, eg
glass or metal or of a combination of materials.
[0129] FIGS. 2A and 2B show a closure used in a first embodiment of
the invention. The closure comprises a top part 20 and a skirt part
21 therefrom. The top part 20 has a bore component 22 extending
from the underside thereof and which, in use, extends into the
container 10. The bore component 22 carries a sealing member 23,
for example an o-ring (see FIG. 4B), so that the sealing member 23
provides a seal between the internal sealing surface 13 of the
container 10 and the bore component 22 when the closure is mounted
on the container (see FIG. 6B) 10. The o-ring is located in a
groove or gland 23B provided on the outer surface of the bore
component 22. Further details of a suitable form of o-ring and
gland are provided in WO2011/151630 referred to above. It should be
noted that the walls of the gland should be smooth to ensure a
satisfactory seal and, in particular, should not include a mould
shut line (which makes it difficult to provide a smooth surface).
The o-ring for use with a wide-mouth closure would typically have a
cross-sectional diameter of 2 to 3 mm. The sealing surface 13 has
an axial length sufficient to accommodate some vertical movement of
the o-ring relative to the container (eg due to pressure variations
in the container) and typically has an axial length of at least 8
mm and in some cases up to 13 mm.
[0130] The skirt part 21 of the closure is provided with an
inwardly projecting second member 24 around an internal surface
thereof, said second member comprising a plurality of
circumferentially spaced apart second portions 24A (four in the
example shown). Each of the second portions has an upper surface
24B, a lower surface 24C, a downward angled end with a first end
surface 24D and an upward angled end with a second end surface 24E.
The upper surface 24B is substantially horizontal in the
circumferential direction and, in the embodiment shown, is
substantially horizontal, and substantially flat, in the radial
direction. The lower surface 11C is also substantially horizontal
in the circumferential direction but may be curved or inclined in
the radial direction, eg as shown in FIG. 7B and FIG. 12B. The end
surfaces 24D and 24E are angled downwardly and upwardly,
respectively, in the circumferential direction and, in the
embodiment shown, these surfaces extend beyond the lower and upper
surfaces 24C and 24B of the second portion 24A, respectively. The
function of the angled ends and end surfaces 24D and 24E will be
described further below with reference to FIGS. 7-18. In the
embodiment show, a further inwardly projecting member is provided
on the skirt portion comprising a plurality of circumferentially
spaced apart third portions 25A. Each of the third portions also
has an upper surface 25B which is substantially horizontal in the
circumferential direction and, in the embodiment shown, is
substantially horizontal, and substantially flat, in the radial
direction. The upper surfaces 25B are at a lower level than the
upper surfaces 24B (viewed when the top part 20 of the closure is
uppermost), the vertical spacing between the upper surfaces 24B and
25B typically being around 2.5-4.0 mm. The third portions 25A also
have angled side faces 25C and 25D.
[0131] The second portions 24A are separated from each other in the
circumferential direction and do not overlap with each other in the
vertical direction.
[0132] The third portions 25A are also separated from each other in
the circumferential direction and do not overlap with each other in
the vertical direction, although they may overlap, at least to some
extent, with the second portions 24A in the vertical direction.
[0133] FIG. 2B also shows small ribs 26 which help prevent the
closure tilting when placed on the container and so assist in
maintaining the closure horizontal.
[0134] The closure is securable to the container 10 by interaction
between the first portions 11A and second portions 24A. FIGS. 4A
and B to 6A and B (described further below) provide schematic
illustrations of interactions between the first and second portions
and the position of the o-ring seal as the closure is secured to
the container.
[0135] In the arrangement shown, the closure is movable between a
first position (FIGS. 4A and B) in which the second portions 24A
(or at least part of the second portions) engage the upper surfaces
11B of the first portions 11A, a second position (FIGS. 5A and B),
following rotation and downward movement of the closure relative to
the container 10, in which the sealing member 23 contacts the
container 10 in a non-sealing position and the second portions 24A
are aligned with spaces between the first portions 11A and a third
position (FIGS. 6A and B), following further rotation and further
downward movement of the closure relative to the container 10, in
which the sealing member 23 has been moved downwards to sealingly
engage the sealing surface 13 of the container and the second
portions 24A are located beneath the first portions 11A and in
contact with substantially the entire circumferential length of the
lower surfaces 11C thereof.
[0136] Maximising the contact between the upper surfaces 24B of the
second portions and the lower surfaces 11C of the first portions in
the third position is of importance. First, it is desirable to
minimise the length of the first portions 11B so as to minimise
their impact on the appearance of the container and to minimise
their contact with the lip of a user drinking from the container
but, secondly, it is desirable to make full use of the contact
between the first and second portions 11A, 24A in order to secure
closure on the container and, in particular, to resist upward
pressure on the closure due to elevated pressure within the
container (eg if it contains a carbonated beverage and/or subject
to an elevated pressure).
[0137] The embodiment shown in FIGS. 1 and 2A and B is designed for
use with carbonated beverages. For a given diameter container (and
hence the area of the closure subject to the internal pressure),
the desired minimum area of contact between the upper surfaces 24B
of the second portions and the lower surfaces 11C of the first
portions can be determined. For example, for a wide-mouth container
having an internal diameter of about 62 mm (and an external
diameter of about 64 mm) housing a carbonated beverage and subject
to temperatures up to 40 degrees C., it is desirable for this
overlap area to be at least about 100 mm2. For an embodiment having
four first portions (and four second portions), this can, for
example, be achieved if they each have a length of 25 mm so the
combined circumferential length of the first portions 11B is about
100 mm (which represents about 50% of the external circumference of
the container at this point) and their radial projection is about
1.0 mm. Greater radial projection of the first portions 11B is
preferably avoided in order to minimise their contact and hence
impact on the lip of a user drinking from the container. The impact
of the first portions on the user's lip can also be reduced by
locating the first portions 11B at a position spaced from the upper
end of the container, for example 10 mm below the top of the
container in the embodiment described.
[0138] For an embodiment having a smaller internal diameter, eg
around 50 mm, the upward pressure on the closure is smaller so the
combined circumferential length of the first portions 11B can be
reduced, eg by using four shorter first portions or by reducing the
number of first portions, eg to three.
[0139] The required combined circumferential length of the first
portions is approximately proportional to the area of the closure
(if their radial projections remains the same, eg 1 mm). For a 35%
reduction in the area of the closure, the combined circumferential
length of the first portions can thus be reduced by about 35%, ie
to an overlap area of about 65 mm2. In the example given, this can
be provided by four first portions having a length of around 16 mm
or three first portions having a length of around 22 mm.
[0140] Embodiments having six sets of first and second portions are
also described below in relation to FIGS. 44 and 45. The combined
circumferential length of overlap between the horizontal elements
of the first and second portions is again maximised although the
larger number of portions reduces the amount of overlap possible.
For embodiments having six set of first and second portions, the
overlap is preferably at least 40% of the circumference of the
container.
[0141] FIG. 3A illustrates movement of the closure towards the
container. Initially the closure is moved axially towards the
container but, as will be explained further below, is then rotated
(about the axis A) relative to the container to secure it thereto.
FIG. 3B shows the closure once mounted upon and secured to the
container.
[0142] As mentioned above, FIGS. 4A and B to 6A and B show
schematic and cross-sectional views of a simplified version of the
container and closure shown in FIGS. 1A and B and 2A and B to help
illustrate the principal stages of movement involved in securing
the closure to the container (whether this be for holding a
carbonated beverage or a non-carbonated beverage). The same
reference numerals are used although it should be noted that some
of the features are shown in a highly schematic form in these
figures compared to the features shown in the embodiments shown in
subsequent figures.
[0143] FIGS. 4A and B relate to a pre-loading stage in which the
second portions 24A (or at least part of the second portions) of
the closure rest upon the upper surfaces 11B of the first portions
11A of the container. FIG. 4B shows a cross-section taken along
line B-B in FIG. 4A. In this position, the o-ring seal 23 of the
closure is spaced from the container.
[0144] The closure is then rotated (in either direction) and moved
downwards from the position shown in FIGS. 4A and B until the
second portions 24A of the closure are aligned with spaces between
the first portions 11A of the container as shown in FIGS. 5A and B.
This schematic representation shows the second portions 24A as they
are passing through the spaces between the first portions 11A. As
will be described further below in relation to FIG. 10A, the
vertical relationship between the first and second portions may be
more complex as if they are angled or curved in the radial
direction, a side view will show them as overlapping, eg as shown
in FIG. 9). FIGS. 5A and B shows the second portions 24A once they
have been moved to a position aligned with spaces between the first
portions 11A so they are then able to pass through those spaces. As
shown in FIG. 5A, the circumferential length of the second portions
24A is smaller than the spaces between the first portions 11A so
they can pass through these spaces although, as shown, they are
preferably of substantially similar length to these spaces. FIG. 5B
is a section taken on line C-C in FIG. 5A.
[0145] As shown in FIG. 5B, in this position, the o-ring 23 is in
contact with the lead-in surface 12 of the container 10 and
supports (or helps support) the closure in this position.
[0146] From the position shown in FIGS. 5A and B, the closure is
moved downwards further onto the container. In a simple arrangement
as shown in this schematic drawing, the closure may be axially
pressed further onto the container. During this downward movement,
the o-ring 23 is compressed between the bore component 22 and the
container and moves from being in contact with the lead in surface
12 to sealingly engage the sealing surface 13 of the container. In
this position the upper surfaces 24B of the second portions are
substantially level with (or slightly beneath) the lower surface
11C of the first portions 11A. The closure is then rotated relative
to the container about axis A so that the second portions of the
container are positioned beneath the first portions of the
container as show in FIG. 6A. In other arrangements (described
below), movement of the second components may be substantially
diagonal so they move downwards and rotate relative to the
container simultaneously. FIG. 6B is a section taken on line D-D of
FIG. 6A.
[0147] In this third position, the closure is secured on the
container and cannot move upwards relative thereto unless it is
rotated to a position in which the second portions can move back
upwards through the spaces between the first portions. Also, as
upper surfaces of the second portions and the lower surfaces of the
first portions are substantially horizontal, upward pressure on the
closure, eg by an elevated pressure within the container, does not
have any tendency to rotate the closure relative to the container.
As shown in this Figure, the upper surface 11B of each of the first
portions is also in contact with substantially the entire length of
the respective first portion beneath which it is positioned. As
mentioned above, this maximises the area of overlap therebetween
and thus the area of overlap available to resist upward forces on
the closure (eg due to elevated pressures in the container).
Furthermore, this means that in order to release this engagement,
it is necessary to rotate the closure relative to the container by
distance sufficient to move the entire length of the second
portions out of contact with the first portions.
[0148] Thus, as shown in FIGS. 4A and B to 6A and B, the second
portions 24A are initially located above the first portions 11A and
are then moved so they pass through the spaces between the first
and finally to a position in which they are located beneath the
first portions 11A. The upper surfaces 24B of the second portions
24A are substantially horizontal and substantially flat throughout
their length (or at least between the inclined ends 24D and 24E of
the second portions 24A), so they can slide horizontally beneath
the lower surfaces 11C of the first portions 11A, the lower
surfaces 11C also being substantially horizontal and substantially
flat throughout their length (or at least between the ends 11D and
11E of the first portions 11A).
[0149] To release the closure from the secured position shown in
FIGS. 6A and B, it is rotated relative to the container so as to
disengage the second portions from the underside of the first
portions and it then moved upwards to the position shown in FIGS.
5A and B. In a simple arrangement without further means to hold the
closure in a venting position, the closure can then be lifted away
from the container. In other arrangements, further rotation will be
required to in order to release the closure from a venting
position.
[0150] FIGS. 7 to 12 illustrate a more detailed sequence of steps
by which a closure such as that shown in FIGS. 2A and B is secured
to a container such as that shown in FIGS. 1A and B (which are
designed for carbonated beverages) and cross-sections showing the
relative positions of the closure and container at each stage, in
particular, the position of the o-ring seal. The sequence of steps
is based on the sequence described above in relation to the
schematic diagrams of FIGS. 4A and B to 6A and B (although modified
to some extent).
[0151] Referring back to FIGS. 1A and B, it will be noted that the
first portions 11A have inclined end surfaces 11D and 11E.
Preferably, these lie at approximately 45 degrees to the
horizontal. As shown in FIGS. 1A and B, the end surface 11D may
extend from the upper surface 11B to the lower surface 11C.
However, as shown in FIG. 1B, the end surface 11E may not extend
all the way from the lower surface 11C to the upper surface
11B.
[0152] The end surfaces 11D and 11E of the first portions may also
have other forms (see FIGS. 24A-24B described below).
[0153] And, as described in relation to FIG. 2B, the second
portions 24A have inclined ends with end surfaces 24D and 24E which
extend beyond the lower and upper surfaces 24C and 24B, eg as shown
in FIG. 2B and in FIG. 7A. These will be described further
below.
[0154] FIGS. 7 to 12 also show the third portion 25A shown in FIG.
2B. As mentioned above, the third portion 25A is provided in a
closure intended for use with a container housing a carbonated
beverage and its function is to retain the closure on the container
when in a venting position (as described further below).
[0155] In FIGS. 7A, 8A, 9, 10A, 11 and 12A the container and
closure are schematically illustrated in dashed lines whereas the
first portions 11A, second portions 24A and third portions 25A are
shown in solid lines in order to highlight the interactions
therebetween. FIGS. 7B, 8B, 10B and 12B shows cross-sectional of
the closure and container in positions corresponding to those of
FIGS. 7A, 8A, 10A and 12A.
[0156] FIGS. 7A and 7B show the closure in a first pre-load stage
in which the third portions 25A rest upon the upper surfaces 11B of
the first portions 11A (FIG. 7A shows these portions overlapping in
the vertical direction as the upper surface 11B of the first
portion and the lower surface of the third portion 25A are angled
or curved in the radial direction as shown in the cross-sectional
view of FIG. 7B). In this position, the o-ring 23 is spaced from
the container 10.
[0157] Following rotation of the closure about the axis A relative
to the container 10 in the tightening direction (clockwise in the
embodiment shown) from the position shown in FIGS. 7A and B, the
third portions 25A drop down into the spaces between the first
portions 11A until the downwardly angled ends of the second
portions 24A rest upon the upper surfaces 11B of the first portions
11A as shown in FIGS. 8A and 8B. In this second pre-load position,
the o-ring 23 is, as shown, still spaced from the container 10
(although only by a small distance). This position (or the position
shown in FIGS. 7A and B) corresponds to the first position
mentioned above in relation to FIGS. 4A and B.
[0158] Upon further rotation of the closure in the closing
direction from the position shown in FIGS. 8A and B, the second
portions 24A slide along the upper surfaces 11B of the first
portions 11A until the downwardly angled ends thereof drops off the
end of the upper surface 11B and the lower surfaces 24C of the
second portions 24A rest upon the upper surfaces 11B of the first
portions 11A (as shown in FIG. 9). It should be noted that FIG. 9
shows the first and second portions overlapping to some extent in
the vertical direction as the upper surface of the first portions
and the lower surface of the second portions are curved or angles
in the radial direction (as shown in FIG. 7B). The second portions
are, nevertheless, resting upon and supported by the upper surface
of the first portions.
[0159] In this position, the closure is slightly lower than in the
position shown in FIG. 8A. And, as will be seen from FIG. 9, the
length of the second portions 24A (in the circumferential
direction), or at least the horizontal part thereof, is preferably
substantially similar to the length of the first portions 11A.
[0160] As will also be seen in FIG. 9, in this position, the third
portions 25A engage the underside of the first portions 11A.
[0161] Upon further rotation of the closure in the tightening
direction from the position shown in FIG. 9, the second portions
24A slide along the upper surface of the first portions and the
third portions 25A slide along the underside of the first portions
11A. This horizontal movement continues until the end surfaces 24D
of the downwardly angled ends of the second portions (which, as
mentioned above, preferably extend beyond the lower surfaces 24C)
reach the end surfaces 11E of the first portions 11A. The second
portions 24A are then aligned with the gaps between the first
portions 11A as shown in FIG. 10A. It should be noted that the
relative vertical positions of the closure and container are
substantially the same in FIG. 9 and FIG. 10A and, as shown, the
third portions 25A are still located beneath the first portions
11A.
[0162] FIG. 10B is a cross-sectional view of the closure and
container in the position shown in FIG. 10A. As will be seen, in
this position the o-ring is in contact with the lead-in surface 12
of the container 10 and the first portion 11A is sandwiched between
the second portion 24A and third portion 25A. The position of the
closure shown in FIGS. 10A and 10B corresponds to the second
position referred to in relation to FIGS. 5A and B. As will be
described further below, this also corresponds to the vent position
when the closure is being removed from the container.
[0163] The vertical position of the closure relative to the
container in both rotational positions shown in FIGS. 9 and 10A and
B is thus determined by the second portions 24A of the closure
resting upon the first portions 11A of the container and/or the
o-ring 23 resting on the lead-in surface 12 of the container
10.
[0164] It will also be noted from FIG. 10A that that the length of
the second portions (in the circumferential direction), or at least
the horizontal part thereof, is substantially similar to (and
slightly less than) the length of the spaces between the first
portions 11A. This is necessary to enable the second portions 24A
to move downwards through the space between the first portions 11A
as will be described below (even though, as will be described, they
move downwards diagonally).
[0165] Upon further rotation of the closure in the tightening
direction from the position shown in FIGS. 10A and B, the inclined
end surface 24D of the downwardly angled end of the second portions
slide down the inclined end surfaces 11E of the first portions so
the closure is driven downwards relative to the container as it
rotated. Preferably, the end surfaces 24D and 11E are inclined at
substantially the same angle, eg around 45 degrees in the
embodiment shown, so the second portions 24A move downwards at this
angle to the axis A. Rotation of the closure thus drives it
downwards until the inclined end surface 24D of the second portions
24A disengage from the lower end of the inclined end surfaces 11E
of the first portions 11A. The upper surface 24B of the second
portions 24A is then level with the underside 11C of the first
portions 11A as shown in FIG. 11. Upon further rotation from this
position, the second portions 24A slide horizontally along the
underside of the first portions 11A until the upwardly angled end
having the end surface 24E (which extends beyond the upper surface
24A) engages the end surface 11E of the first portion and stops
further rotation as shown in FIG. 12A. It will be seen that in this
position, the second portions 24A are located beneath the first
portion 11A and the substantially horizontal upper surface 24B of
the second portion 24A is in contact with substantially the entire
length (in the circumferential direction) of the substantially
horizontal underside 11C of the first portion 11A. The second
portions 24A are thus securely located under the first portions 11A
and the area of contact therebetween (which resists upward movement
of the closure due to elevated pressures within the container) is
maximised.
[0166] FIG. 12B shows a cross-section of the closure and container
in the position shown in FIG. 12A. As will be seen the o-ring has
been driven downwards from the lead-in surface 12 (the position
shown in FIG. 10B) to sealingly engage the substantially
cylindrical sealing surface 13 around the interior of the
container. This involves compression of the o-ring and the above
arrangement in which the downward movement of the closure which
causes this is effected by rotation of the closure provides a
significant mechanical advantage in providing the force required to
compress the o-ring, particularly for a wide-mouth closure in which
the closure has a relatively large diameter (eg compared to a
bottle cap).
[0167] The position shown in FIGS. 12A and 12B corresponds to the
third position described in relation to FIGS. 6A and B.
[0168] It will be appreciated from the above description that the
closure is driven downwards as it is rotated from the position
shown in FIG. 10A to the position shown in FIG. 11. This rotation
is through a relatively small angle (depending on the length and
angle of the inclined end surface 11D) and may typically be in the
range 5 to 15 degrees.
[0169] And it will be appreciated that the vertical distance by
which the closure is driven downwards is determined by the angle
and length of the end surfaces 24D and extension of the end
surfaces 24D beyond the lower surface 24C enables the closure to be
driven down a sufficient distance so the o-ring 23 is driven down
from the lead-in surface 12 and into sealing engagement with the
sealing surface 13.
[0170] It will also be appreciated from the above description that
once the closure has been driven down to the position shown in FIG.
11, the further rotation to the position shown in FIG. 12A, does
not involves further depression of the closure nor further
compression of the o-ring 23 but securely engages the second
portions beneath the first portions by maximising the area of
overlap therebetween. In the embodiment shown, the closure rotates
through an angle in the range 40-50 degrees between the positions
shown in FIG. 11 and FIG. 12A. This also means that once in the
position shown in FIG. 12A, the closure is securely held on the
container and needs to be rotated back through this angle (40-50
degrees) before it can be removed from the container (as will be
described further below). As this rotation is horizontal (rather
than being inclined as in the case of a helical thread) it is not
necessary to provide any detent or other feature that needs to be
overcome (eg involving vertical movement of the closure) before
this rotation can occur. However, in other embodiments (described
further below), the first and/or second portions may be modified to
provide some additional resistance to rotation in the loosening
direction.
[0171] FIGS. 13 to 18 illustrate a more detailed sequence of steps
by which the closure of FIGS. 2A and B is removed from the
container of FIGS. 1A and B and cross-sections showing the relative
positions of the closure and container at each stage, in
particular, the position of the o-ring seal. This is essentially
the reverse of the loading sequence described above.
[0172] To release the closure from the locked position shown in
FIG. 12A and FIG. 12B, the closure is rotated about the axis A in
the loosening direction (anti-clockwise in the embodiment shown)
relative to the container 10. Initially, the closure is rotated to
the position shown in FIG. 13 until the end face 24E of the
upwardly angled end of the second portion 24A (which, as mentioned
above extends beyond the upper surface 24B of the second portion
24A) contacts the end surface 11D of the first portions 11A. Then,
upon further rotation from this position, the inclined end face 24E
rides up the inclined end face 11D, as shown in FIG. 14, until the
third portions 25A engage the underside of the first portions 11A,
as shown in FIGS. 15A and B, to arrest the vertical movement of the
closure. During this upward movement of the closure, the o-ring 23
moves from sealingly engaging the sealing surface 13 to a position
in which it is located on the lead-in surface 12 as shown in FIG.
15B. It will be appreciated that the position shown in FIG. 15A and
FIG. 15B corresponds to the position shown in FIG. 10A and FIG.
10B.
[0173] The position shown in FIG. 15A and FIG. 15B is the vent
position. Excess pressure within the container can be released by
escape of gas between the o-ring seal 23 and the lead-in surface 12
and, in particular, through the venting grooves 14 in the lead-in
surface (shown in FIG. 1A). The closure is, however, securely held
on the container by the engagement of the third portions 25A with
the underside of the first portions 11A as shown in FIG. 15A. As
shown in FIG. 15B, the first portion 11A is sandwiched between the
second portion 24A and third portion 25A.
[0174] As the closure is rotated further in the loosening direction
from the position shown on FIG. 15A, the third portions 25A slide
along the underside of the first portions 11A and the second
portions 24A slide along the upper surface 24B of the first
portions 11A until the downwardly angled end of the second portion
that extends beyond the lower surface 24C thereof reaches the
inclined end surface 11D of the first portion 11A. At the same
time, the third portions 25A reach a position in which they
disengage from the underside 11C of the first portions 11A (so no
longer resist upward movement of the closure). This is the position
shown in FIG. 16 (which corresponds to the position shown in FIG.
9).
[0175] As the closure is rotated further from the position shown in
FIG. 16, the upwardly angled end of the second portion rises up the
inclined end surface 11D of the first portions 11A and an inclined
side face 25B of the third portion 25A rides up the inclined end
face 11E of the first portion 11A so the closure moves diagonally
upwards as shown in FIG. 17. If the container houses a carbonated
beverage, the pressure produced by this within container will
assist this upward movement of the closure. The action of the
upwardly angled ends of the second portions in driving the closure
upwards as it is rotated in the loosening direction is however
desirable for non-carbonated applications and for applications in
which the pressure within the container is lower than that outside.
Also, once a carbonated beverage has been opened, the pressure
within the container drops significantly and if the user re-closes
the container, the driving up feature will help lift the closure
when it is opened again.
[0176] Upon further rotation of the closure from the position shown
in FIG. 17, the third portion 25A is able to move upwards through
the space between the first portions 11A and the closure is free to
be lifted away from the container as shown in FIG. 18.
[0177] As described above, the inclined ends of the second portions
24A respectively serve to drive the closure downwards and upwards
relative to the container and they also respectively act as stops
to limit rotation of the closure clockwise and anti-clockwise
relative to the container. The angle and length of the inclined end
portions will depend on the application, the dimensions of the
closure and the number of thread portions provided around its
circumference. With steeper angles the torque required to drive the
closure down to the sealed position will be greater but the angle
through which the closure needs to be rotated to achieve this will
be smaller (and hence the inclined portions will be relatively
short). The inclined portions preferably make an angle of 45
degrees or less with the horizontal and more preferably an angle in
the range 15 to 20 degrees.
[0178] For containers designed for use with a non-carbonated
beverage, the area of overlap between the first and second portions
in the secured position can be much reduced compared to embodiments
for carbonated beverages as the upward pressure the closure needs
to be able to withstand is much reduced. Nevertheless, it is still
desirable to maximise the overlap between the first and second
portions, ie by making them substantially the same length as each
other in the circumferential direction, so the total
circumferential length of the first portions can be minimised (and
so minimise their impact on the user's lip) whilst still making
full use of the amount of overlap possible (to ensure secure
attachment of the closure and avoiding indentation damage to the
first portions by the second portions.
[0179] FIGS. 19A and B to 21A and B show schematic and
cross-sectional views of a simplified version of the container and
closure similar to those of FIGS. 4A and B to 6A and B in relation
to a container suitable for use in some non-carbonated beverage
applications. This is similar to the arrangement shown in FIGS. 4A
and B to 6A and B except that the container has fewer first
portions 11A (two in the example shown rather than four) and the
closure has fewer second portions 24A (again, two in the example
shown rather than four).
[0180] FIGS. 19A and 19B show a pre-loading stage in which the
second portions (or at least a part of the second portions) rest on
the first portions and the o-ring 23 is spaced from the container.
Again, it should be noted that these figures show schematic
representations of the parts so there is not necessarily a
one-to-one relationship with the parts shown in the Figures
described above.
[0181] FIGS. 20A and 20B show a loading position in which the
o-ring 23 rests on the lead-in surface 12 of the container and the
second portions 24A are aligned with the spaces between the first
portions 11A.
[0182] FIGS. 21A and 21B show a sealed position in which the second
portions 24A have been moved further downwards and beneath the
first portions 11A and the o-ring seal has moved downwards to
sealingly engage the sealing surface 13 of the container.
[0183] As the container is for a non-carbonated beverage, the area
of overlap between the first and second portions in the secured
position can be much reduced compared to embodiments for carbonated
beverages as the upward pressure the closure needs to be able to
withstand is much reduced. Nevertheless, it is still desirable to
maximise the overlap between the first and second portions, ie by
making them substantially the same length as each other in the
circumferential direction, so the total circumferential length of
the first portions can be minimised (and so minimise their impact
on the user's lip) whilst still making full use of the amount of
overlap possible (to ensure secure attachment of the closure and
avoiding indentation damage to the first portions by the second
portions.
[0184] A cross-section of another embodiment of the closure is
shown in FIG. 22. This is similar to the closure described above
except that the downwardly and upwardly angled ends of the second
portions and the end surfaces 24D and 24E thereof are longer and
extend at a slightly shallower angle, eg in the range 30-40 degrees
to the horizontal. This helps reduce the torque required to rotate
the closure in the tightening and the loosening direction,
particularly at the stage in which the o-ring is driven downwards
into the container and when it is driven upwards for withdrawal
from the container. The movement of the horizontal parts of the
second portions, and their relationship to the spaces between the
first portions remains as in the embodiments described above.
[0185] FIG. 23 shows an enlarged portion of the cross-section shown
in FIG. 22 to illustrate a method of manufacture of the closure
(and of that of the embodiments described above).
[0186] When known forms of injection moulded closures are formed of
a relatively flexible material such as polypropylene or
polyethylene, threads on the inside of a skirt portion of the
closure are typically flexed or "bumped" off the mould forming
these parts. However, if a stiffer plastics material is used, this
may no longer be feasible and, instead, the mould too may have a
"collapsing core" to form such threads. Typically, a collapsing
core may have 4, 6 or 8 internal sliders which are moved radially
inwards to evacuate the area above the internal threads. However,
the use of such sliders, then prevents other features being formed
on the under-side of the top part of the closure, particularly at
positions close to the skirt part as these may prevent the sliders
moving inwards.
[0187] To overcome this problem, there is provided a method of
manufacture of a closure having a top part 20 and a skirt part 21,
the top part having a bore component 22 (which in use extends into
the container opening), a recess 23B in a radially outwardly facing
surface of the bore component 22 for receiving a sealing member,
such as an o-ring 23, and the skirt part 21 having an inwardly
projecting retaining member 24 around an internal surface thereof
in the form of a plurality of circumferentially spaced apart
portions 24A. Such a closure can be formed by an injection moulding
process which includes the followings steps:
[0188] providing an injecting moulding tool having a mould cavity
for forming outwardly facing features of the top part 20 and of the
skirt part 21 and a tooling core comprising an inner component for
forming at least said recess 23B of the bore component 22 and an
outer component for forming at least said retaining members 24A of
the skirt part,
[0189] the inner component being arranged so that once the closure
has been formed, it can be withdrawn therefrom substantially
axially,
[0190] the outer component comprising a collapsing core such that,
once the inner component has been withdrawn, its parts can move
radially inwards, at least partially into the space previously
occupied by the inner component, to disengage it from said
retaining portions 24A, so that it can then be withdrawn
substantially axially from the closure.
[0191] Thus, a mould core is used which has an inner, cylindrical
component which is used to form the outer parts of the bore
component 22, such as the recess 23B in which the o-ring will sit,
and an outer cylindrical set of sliding cores, which are used to
form the inner features of the skirt part 21, ie the second
portions or retaining members 24A.
[0192] Once the closure has been formed, the mould core can be
removed by the following sequence of steps:
[0193] First, the inner cylinder is withdrawn axially from the
closure as indicated by arrow A1. This leaves a space radially
inward of the outer cylinder having a width C1, eg 2.4 mm, into
which the outer cylinder can `collapse`.
[0194] Second, the outer cylindrical cores are `collapsed` radially
inwards, as indicated by arrow A2, into the space vacated by the
inner cylinder of the mould core.
[0195] Finally, the inner cylindrical core, having been collapsed
so as to disengage from the retaining members 24A, can be axially
withdrawn as indicated by arrow A3.
[0196] The closure illustrated in FIGS. 22 and 23 also has a
plurality of radially outwardly projecting resilient fingers 23C
adjacent the lower edge of the recess 23B for axially retaining the
o-ring in the recess (so the o-ring remains on the bore component
22 when the bore component is withdrawn from a container). The
fingers 23C flex radially inwards to permit the inner component of
the mould core to disengage therefrom when the inner component is
withdrawn.
[0197] The method described above is particularly suitable when the
radial spacing between the radially outermost part of the bore
component 22 and the radially innermost part of said retaining
portions 24A of the retaining member 24 is small. In the present
case, this spacing corresponds to the thickness of the container
wall which, when the closure is mounted on a container, occupies
this space.
[0198] In a typical example of a wide mouth closure, this radial
spacing may be 4.0 mm or less and preferably 3.9 mm or less.
[0199] The retaining portions 24A project at least R mm from an
inner wall of the skirt part 21, where R is at least 1.0 mm and
preferably at least 1.3 mm.
[0200] It will be appreciated that withdrawal of the inner
component, provides a space which permits the parts of the outer
component to move or collapse radially inwards by at least R and
preferably R plus 0.5 mm or more (to allow for shrinkage of the
closure once formed).
[0201] As indicated above, the closure may be formed of a plastics
material the rigidity of which is such as to require the use of a
collapsing core to disengage the core from said retaining portions.
A preferred material is a plastics material comprises
polyoxymethylene (as described above)
[0202] It will be appreciated that the outer cylindrical component
of the mould core is relatively thin in the radial direction
(corresponding to the dimension C2, eg 1.5 mm). In some cases it
may be desirable to strengthen these parts by the provision of a
strengthening rib on the outer surface thereof. The embodiment
shown in FIG. 22 has a gap 24A in each of the retaining members 24A
to accommodate such a rib so the rib can locally increase the
thickness of the outer cylindrical components by R, eg 1.3 mm.
Although the upper and lower surfaces 24B and 24C have this small
gap within them, they still provide the functions described above
in relation to the earlier embodiments.
[0203] FIGS. 24A and 24B show side views of part of a container
showing alternative shapes of the first portions provided thereon
and shows the upper and lower surfaces 11B and 11D and the end
surfaces 11D and 11E.
[0204] The first portion shown in FIG. 24A comprises horizontal
upper and lower surfaces and inclined end surfaces 11D and 11E
extending between these. The upper and lower surfaces and the end
surfaces are shown as meeting at points although, in practice these
may be slightly rounded due to manufacturing processes and
tolerances. The upper and lower surfaces provide the functions
described in the earlier embodiments and the inclined end surfaces
act as drive down and drive up surfaces also as described
above.
[0205] The shape of the first portion shown in FIG. 24B is similar
to that of the first portion shown in FIG. 1B except that the end
surface 11D is at a slightly shallower angle and slightly longer
than that shown in FIG. 1B, eg to correspond with the shallower
angle of the end surface 24E of the closure shown in FIG. 22. This
shape is shorter and more rounded than that shown in FIG. 24A so
has less impact on the user's lips yet the surfaces thereof provide
the functions described.
[0206] FIGS. 25A and 25B showing cross-sectional views
corresponding to FIG. 22 of two further embodiments of a closure
formed of metal (instead of a plastic material). FIGS. 27A and 27B
show perspective views from above and below of a similar metal
closure and FIG. 27C shows a cross-sectional view of this enclosure
with an o-ring mounted therein.
[0207] The embodiment shown in FIG. 25A has a concave bore feature
22 (when viewed from above). The outer surface of this bore feature
has an indent 23B for holding an o-ring.
[0208] The closure can be formed in a pressing operation in which
the bore feature 22 is formed by pressing an inverted shape. The
side wall of the bore feature 22 is then rolled to form the indent
23B for the o-ring.
[0209] The embodiment shown in FIG. 25B is similar except that the
bore feature 22 is then reverse formed (from the position shown in
FIG. 25A), eg by stamping, so the upper surface of the closure has
a more conventional convex form (when viewed from above). The
reverse forming creates a double backed fold 22A at the base of the
indent which provides additional hoop strength to resist inwards
flexing of the bore feature 22 (which might impair the seal between
the o-ring and the container) or may be formed by further grooves
rolled in the outer surface to form projections 25A on the inner
surface (as shown in FIGS. 3A and 3B). In both embodiments, the
skirt 21 of the metal closure has grooves rolled in its outer
surface to form projections 24A on the inner surface which provide
the second portions. The third portions 25A are formed in the lower
lip of the closure, eg as it is turned upwards to provide a convex
edge (as in conventional metal closures).
[0210] The function of the second and third portions 24A and 25A
has been described above. The shape and function of these portions
formed in a metal cap maybe essentially similar to those of second
and third portions of a plastic cap (eg as described in
GB1413249.2). The inner surface of the skirt of the metal closure
is thus formed to have a shape which is similar to that of the
inner surface of the embodiment described above formed of plastic
(or other mouldable materials). However, the wall thickness (gauge)
is substantially less, eg in the range 0.18 mm-0.22 mm (compared to
around 1.65 mm for a plastic closure).
[0211] The metal used may be similar to that used in conventional
metal closures, eg as used for other types of twist off caps, such
as tinplate (a low carbon mild steel coated on both surfaces with
an electrolytic deposition of tin). This material typically has a
gauge of around 0.14-0.18 mm and a yield stress of around 580-620
MPa.
[0212] The metal closures shown in FIGS. 25A and B and 27 have
inwardly projecting first, second and third members which function
in a similar manner to the corresponding projections described in
relation to the closures illustrated in earlier figures formed of a
plastic material. The metal may be used to close a container formed
of a plastics material (as described above) or other material, eg a
metal container.
[0213] FIG. 26 shows a cross-sectional view of a further embodiment
of a container formed of metal (instead of a plastic material) that
may be used with the metal closures described in relation to FIGS.
25A and 25B and FIGS. 27A, B and C (or with plastics enclosures as
described in the earlier embodiments). The metal container is
designed to correspond to that shown in FIG. 1B. The metal is
formed, eg by stamping from the interior, so that the outer surface
of the container has projecting first portions 11A which have
substantially the same shape and function as those described in the
earlier embodiments (the cross-section in FIG. 26 shows these
features as seen from the interior of the container).
[0214] The outer surface of this part of the metal container is
thus formed to have a shape which is similar to that of the outer
surface of the corresponding part of the embodiment described above
formed of plastic (or other mouldable materials). However, the wall
thickness (gauge) is substantially less, eg in the range 0.14
mm-0.18 mm (compared to around 2.0-2.5 mm in the neck portion for a
plastic container and around 0.7-1.0 mm in the portion of the
container formed by blow moulding).
[0215] The uppermost part of the metal container is formed so as to
provide an inclined lead-in surface 12 for receiving an o-ring (as
described in earlier embodiments) and venting channels 14 within
this lead-in surface. The upper part of the container may have a
rolled edge as shown and the lead-in surface and venting channels
pressed or stamped on the inner surface of this. The inner surface
of this part of the metal container is thus formed to have a shape
which is similar to that of the inner surface of the corresponding
part of the embodiment described above formed of plastic (or other
mouldable materials). However, the wall thickness (gauge) is again
substantially less (as described above).
[0216] The metal container may be formed from a metal similar to
that used in conventional steel beverage containers. Such materials
typically have a gauge of around 0.20-0.25 mm and a yield stress of
around 350-420 MPa.
[0217] The weight and material cost of a metal closure or container
may thus be less than the weight and material cost of a
corresponding closure or container formed of a plastics
material.
[0218] As mentioned above, FIGS. 27A and 27B show perspective views
from above and below of a further embodiment of a metal closure
used in embodiments of the invention.
[0219] FIGS. 27A, B and C and 28A and B show a further embodiment
of a metal closure that may be mounted on a plastic container or a
metal container similar to those described above. FIGS. 27A, B and
C shows the closure prior to it being mounted on a container, FIG.
28A shows the closure in a position corresponding to that described
in relation to FIG. 15A (and which corresponds to a venting
position) in which the o-ring initially engages the inclined lead
in surface and FIG. 8B shows it when mounted on the container (and
shows how the o-ring carried by the closure is deformed in this
position).
[0220] The metal closure can again be formed in a pressing
operation in which the bore feature 22 is formed by pressing an
inverted shape. The side wall of the bore feature 22 is then rolled
to form the indent, or recess 23B, for receiving an o-ring 23.
[0221] The skirt 21 of the metal closure has grooves rolled in its
outer surface to form projections 24A on the inner surface which
provide the second portions. Grooves are also rolled in the outer
surface of the skirt 21 to form projections 25A on the inner
surface which provide the third portions. Alternatively, in another
arrangement (eg see FIGS. 11, 19A and B and 21A and B), the third
portions 25A may be formed in the lower, distal edge of the closure
by curling the edge inwards, eg as it is turned inwards to provide
a convex edge (as in conventional metal closures).
[0222] The second and third portions 24A and 25A have substantially
the same shape and function as those described above and in the
first embodiment. The inner surface of the skirt of the metal
closure may be thus formed to have a shape which is similar to that
of the inner surface of a closure formed of plastic (or other
mouldable materials). However, the wall thickness (gauge) of the
metal closure is substantially less, eg in the range 0.18 mm-0.22
mm (compared to around 1.65 mm for a plastic closure).
[0223] As in the first embodiment, the metal used may be similar to
that used in conventional metal closures, eg as used for other
types of twist off caps, such as tinplate (a low carbon mild steel
coated on both surfaces with an electrolytic deposition of tin).
This material typically has a gauge of around 0.14-0.18 mm and a
yield stress of around 580-620 MPa.
[0224] There are two main differences between the metal closure
shown in FIGS. 27A, B and C compared to that shown in FIGS. 25A and
B. First, the shape of the recess 23B for receiving the o-ring seal
and, second, the shape of the bore feature 22 above the recess
23B.
[0225] In the embodiment shown in FIGS. 27A, B and C, the recess
23B comprises an upper side wall 23C which is substantially planar
and lies substantially perpendicular to the axis A, a lower side
wall 23D which slopes downwards and radially inwards and a back
wall 23E which is substantially planar and substantially parallel
to the axis A and joins the upper and lower sidewalls 23C and 23D.
It will be appreciated that as the recess 23B is formed by a
rolling operation, the join between the back surface and the upper
and lower side walls is curved.
[0226] The formation of a closure from a plastic material by
injection moulding (eg as described in GB1413249.2), imposes
restraints on the manner in which the o-ring is retained on the
bore component due to the need to be able to release the closure
from the mould. In practice, this requires the o-ring to be
retained by the use of relatively short flexible fingers so the
closure can be sprung out of the mould. The formation of a closure
from metal plate enables the o-ring to be retained by a lower side
wall 23D as described above and, importantly, for this side wall to
extend radially outwards further than flexible fingers such as
those mentioned above. This enables the o-ring to be retained more
securely on the bore component (so reducing any tendency for it to
become detached from the bore component as it is withdrawn from the
container). In addition, the further the lower side wall 23D
projects radially outwards, the less the possibility that the
elevated pressure within the container can act on radially inner
portions of the o-ring 23 so as to potentially stretch the o-ring
and/or for a portion of the o-ring being dislodged from the recess
23B as it is forced upwards by a sudden release of pressure within
the container (and the consequent sudden release of gas) during
venting. If a portion of the o-ring 23 is forced upwards into a gap
between the bore component 22 and the container 10 (this gap
increasing in size as the closure is moved upwards from the
position shown in FIG. 28B to the position shown in FIG. 28A) by
this release of gas, it may be more difficult to maintain a
controlled venting of the container and, when the closure is
refitted to the container, the dislodged portion of the o-ring 23
can become trapped between the frusto-conical portion 22A of the
bore component and the container 10 and so prevent re-closure
and/or re-sealing of the container. If the lower side wall 23D of
the recess extends radially outwards beyond the lowest part of the
o-ring 23, the pressure within the container (and the release of
gas on venting) acts more on radially outer portions of the o-ring
23 and so does not have a tendency to stretch the o-ring or
dislodge it from the recess 23B.
[0227] In a preferred arrangement, the upper side wall 23C extends
in a radial direction by a distance f (f being at least 1/2 the
diameter of the o-ring cross-section prior to compression) from the
back wall 23E and the lower side wall 23D extends in a radial
direction by a distance s from the back wall 37C, the distance s
being at least 1/2 of the distance f.
[0228] Alternatively, or additionally, the distance s is preferably
at least 1/3 of the diameter of the circular cross-section of the
o-ring (prior to deformation of this cross-section), and preferably
1/3-2/3 of the diameter of the o-ring.
[0229] For embodiments having an external o-ring, the situation is
reversed as the lower side wall of the recess has the dimension f
and the upper side wall the dimension s, as in this case the o-ring
is pressed into contact with the lower side wall by elevated
pressure within the container and the upper side wall merely helps
retain the o-ring in the recess prior to the closure being fitted
to the container.
[0230] As shown in FIGS. 27A, B and C, the portion 22A of the bore
component 22 above the recess 23B is inclined to the axis A and
thus has a substantially frusto-conical shape and the angle of its
inclination corresponds to the angle of inclination of the lead-in
surface 12 of the container, this lead-in surface 12 also being
frusto-conical (although including venting channels 14 in some
arrangements). The frusto-conical portion 22A of the bore component
thus lies adjacent and substantially parallel to the lead-in
surface 12 when the closure is mounted on the container. By shaping
the bore component 22 so as to match the shape of the uppermost
portion of the internal surface of the container in this way, any
space between the bore component 22 and the container 10 above the
o-ring 23 can be minimised. This is desirable as it helps minimise
any potential for liquid (or other matter) to become trapped in
this area (which might give rise to contamination and/or might
impede removal of the closure, as well as being unsightly for the
consumer).
[0231] FIGS. 29 and 30A and B show another embodiment of a metal
closure. This is similar to the embodiment shown in FIGS. 27A and B
and 28A and B except for the shape of the recess 23B in which the
o-ring is located. The lower side wall 23D' of the recess 23B in
this embodiment is substantially planar and substantially
perpendicular to the axis A (rather than being inclined as in the
second embodiment). The lower side wall 23D' may also extend
radially outwards from the back wall 23E by a distance s similar to
which the upper side wall 23C extends radially outwards. The o-ring
23 is thus located in a recess 23B, or gland, which has a
substantially rectangular shape (with rounded corners). This is the
preferred shape of a gland for an o-ring as discussed in more
detail in WO2011/151630, which is hereby incorporated herein by
reference for its description. This shape gland is also able to
provide a seal in positive and negative pressure applications, ie
where the pressure within the container is greater than that
outside the container and vice versa.
[0232] As mentioned above, the o-ring sealing member 23 may also be
provided within a recess 23A in the skirt portion 21 of the closure
and arranged to seal with an external sealing surface 10C of the
container 10. FIGS. 31A and 31B show cross-sections of such an
arrangement in a sealed position and a venting position,
respectively. FIGS. 31A and 31B show a metal closure mounted on a
container formed of a plastics material (or other mouldable
material). The uppermost portion of the external surface of the
container is inclined to the vertical so as to provide an inclined
surface 10B on which the o-ring 23 rests when the closure is
initially mounted on the container 10 and then acts to compress the
o-ring 23 in the horizontal direction as the closure is rotated
downwards towards the sealing position. The inclined surface 10B
thus provides the same function as the lead-in surface 12 described
in earlier embodiments (except that the horizontal force it applies
to the o-ring is in the radially outward direction rather than
radially inward). In both cases, the cross-section of the o-ring 23
is deformed by the compressive force within a gland defined by the
recess 23A or groove in which the o-ring is located and the sealing
surface 10C of the container. And, as described above, the o-ring
sealing member 23 is able to move and/or deform within this gland
so as to provide a liquid and gas-tight seal between the closure
and the container, and in particular when there is a pressure
differential across the seal, eg due to elevated pressure within
the container. Venting grooves (not shown) may be provided in the
inclined surface 10B in a similar manner to those provided in the
lead-in surface 12.
[0233] As the closure shown in FIGS. 31A and B uses an external
o-ring seal 23, the closure does not need to be provided with a
bore feature projecting into the mouth of the container (although
this can still be provided if desired, eg to minimise the air space
between the closure and the contents of the container). FIGS. 31A
and B shows the closure having a substantially flat top part 20
extending across the mouth of the container (although other concave
or convex shapes may be used).
[0234] FIGS. 32 to 39A and B illustrate embodiments in which the
closure is formed of two initially separate portions, a skirt
portion and a closing portion, such that the skirt portion may be
first secured to the neck of a container and a closing portion
subsequently irreversibly secured to the skirt portion so as to
complete the closure (typically after the container has been
filled, eg with a beverage or some other foodstuff or other
material). Such closures (and associated container and methods of
forming and filling the same) are further described in co-pending
application GB1522544.4.
[0235] With known removable closures on narrow mouth container such
as bottles, the filling technique intentionally creates a froth
(known as fob) which is used to expel air form a headspace above
the liquid beverage and, as the container neck is relatively
narrow, the filling process can be accurately controlled to
minimise over-fill or spillage (so such filling lines do not
usually have a rinsing station to rinse the container neck prior to
fitting a closure to the container). With a wide mouth container
this is much more difficult to achieve as filling within 10 mm of
the brim is likely to cause overflowing and contamination of the
threads on the container neck so rinsing might be required prior to
fitting the closure. The alternative is to fill in a manner which
does not cause fobbing but if no fob is created, air is not
excluded from the headspace so the contents are exposed to
oxidation.
[0236] For beverages stored in cans a different filling technique
is used. The can is filled with liquid beverage and the level of
frothing is controlled by flushing with carbon dioxide together
with a `bubble breaking` method (using jets of liquefied gas). Once
the can is full, the end of the can is immediately secured to the
end of the can body, eg by a seaming operation whilst flushing
continues. A typical can filling line thus has both a filler (with
associated gas flushing apparatus) and a seaming station for
immediately attaching the end of the can to the can body to form a
closed container with minimal oxygen therein.
[0237] A significant advantage of the embodiments of FIGS. 32 to
39A, B and C is to make use of such a can filling and closing line
to create a container having a closure releasably secured thereto
and, in particular a wide mouth closure. Thus, these embodiments
exploit the fact that a conventional can filling line is combined
with a seamer to close the can immediately after it has been filled
by providing a particular form of container which can be filled and
closed in the same way yet provides a container with a releasable
wide-mouth closure.
[0238] The invention thus enables a container having a releasable
closure (and preferably a wide mouth closure and/or a closure which
can be re-fitted after removal), to be filled on a conventional can
filling line and for the container to be closed by using the
seaming apparatus to irreversibly secure a closing portion to the
skirt portion so as to complete formation of the releasable
closure.
[0239] As mentioned, the closing portion can be irreversibly
secured to the skirt portion by a seamed joint, ie the same
technology as used to secure the end of a conventional beverage can
(such as a ring-pull can). This enables an improved form of
container (ie a with mouth container with a releasable closure and,
optionally, re-sealable closure) to be compatible with existing can
filling and closing lines with little or no modification. This
avoids the need for significant capital investment in new or
extensively modified manufacturing plant and so enables an improved
form of container, such as a beverage container, to be manufactured
without the need for capital investment in new manufacturing
apparatus.
[0240] The closures shown in FIGS. 32 to 39A, B and C preferably
have a threadform similar to that described above and in in
co-pending GB1413249.2. Other threadforms can be used (but will not
have the additional advantages of those described in
GB1413249.2).
[0241] The closure also preferably has sealing means in the form of
an o-ring as described above and in WO2011/151630 and GB1413249.2.
In some embodiments the o-ring may engage a sealing surface around
the exterior of the neck portion of the container whereas in other
embodiments the o-ring may engage a sealing surface around an
internal surface of the neck portion of the container.
[0242] It will be appreciated that when the container is filled on
a conventional can filling and closure line (as discussed above),
it is important that a good seal is provided between the skirt
portion of the closure and the container (both during the filling
operation and in the finished closed container). The use of an
o-ring seal is particularly advantageous for providing such a seal
when the container is to contain a carbonated beverage (or other
pressurised contents).
[0243] As mentioned above, the o-ring is preferably mounted in a
groove in the skirt portion of the closure or in a bore member
which projects into the mouth of the container. The bore member is
preferably part of the skirt portion but other arrangements in
which it is part of the closing portion can also be envisaged.
Other forms of sealing member for proving a seal between the
closure and the container can be used (particularly in applications
in which elevated pressures within the container do not need to be
catered for).
[0244] As described above, if the container is designed to contain
a carbonated beverage (or other pressurised contents), the closure
is also preferably designed to be movable between a first secured
and sealed position to a second secured venting position (in which
the contents can vent but the closure remains attached to the
container) and then to an open position. Other forms of venting may
however be used.
[0245] As indicated above, securement of the skirt portion to the
neck of the container by means of a thread form such as that of
GB1413249.2 which will be briefly described below. Assembly of the
closing portion onto the skirt portion will then be described.
[0246] FIG. 33 shows a wide-mouth container 10 having has an
opening 10A defining an axis A and has an outwardly projecting
first member around an external surface of the container 10, the
first member comprising a plurality of circumferentially spaced
apart first portions 11A (four in the example shown), each first
portion 11A has an upper surface 11B, a lower surface 11C, a first
end surface 11D and a second end surface 11E. The upper surface 11B
is substantially horizontal in the circumferential direction but
may be curved or inclined in the radial direction. The lower
surface 11C is also substantially horizontal in the circumferential
direction and, in the embodiment shown, is substantially
horizontal, and substantially flat, in the radial direction.
[0247] The spaced apart portions of the first member form an
intermittent, outwardly projecting lip which may be located at or
near the upper end of the container 10 or, as in the embodiment
shown, spaced from the upper end of the container 10, eg by a
distance in the range 6-15 mm and preferably 9-12 mm. The
horizontal elements of the first portions 11A are separated from
each other in the circumferential direction and do not overlap with
each other in the vertical direction.
[0248] As in the embodiment shown in FIGS. 31A and B described
above, in the embodiment of FIGS. 33 and 34, the uppermost portion
10B of the external surface of the container is inclined to axis A
so as to provide a lead-in surface to compress/deform the o-ring as
the skirt portion of the closure is drawn downwards relative the
container. The inclined surface leads to a sealing surface 10C
which may also be slightly inclined to the axis A (as shown) or may
be a substantially parallel sided, cylindrical portion of the
external surface of the container 10. In some embodiments a
plurality of venting grooves or passages (not shown) may be
provided at spaced apart positions around the circumference of the
lead-in surface to facilitate venting of the container.
[0249] The container shown in FIG. 33 again has a handling groove
15 in the external surface thereof to facilitate handling of the
closure as it passes through automatic machinery, eg during
manufacture and subsequent processes such as washing, filling,
closing etc. In other embodiments (not shown), the handling groove
may not be required.
[0250] In some embodiments, the container may be formed of a
plastics material, eg polyethylene terephthalate (PET), and is
typically formed in a two-stage moulding process: forming a preform
in a first injection moulding stage which forms the features above
the groove 15 and then a second blow moulding stage in which the
preform is blown to form the container shape beneath the groove 15.
The first portions 11A and/or the groove 15 may be used to hold the
preform during the blow moulding stage.
[0251] The container may also be formed of other materials, eg
glass or metal or of a combination of materials. As mentioned
above, some embodiments of the invention comprises a metal
container with a metal closure, although a metal closure may also
be provided on a container formed of another material, eg plastic
or glass.
[0252] FIG. 32 shows a skirt portion 21 of a metal closure. The
closure initially comprises the skirt portion 21 and a separate
closing portion 22C (shown in FIG. 35). The skirt portion 21
carries a sealing member 23, for example an o-ring, so that the
sealing member 23 provides a seal between an external sealing
surface 10C of the container 10 and the skirt portion 21 when the
skirt portion 21 is mounted on the container 10 as shown in FIG.
34. The o-ring 23 is located in a groove or gland 23A provided in
the inner surface of the skirt portion 21.
[0253] The following description refers to the initial mounting of
the skirt portion 21 (prior to securement of a closing portion 22C
thereto). Once the closure has been completed by irreversibly
securing the closing portion 22C to the skirt portion 21 (as
described further below) and following removal of the closure from
the container 10 by a user, the closure can subsequently be
re-mounted on the container 10 to close it again. This involves the
same sequence of interactions between the thread features (first
portions 11A and second portions 24A) of the skirt portion and the
container described below.
[0254] In the arrangement shown, the skirt portion 21 of the
closure is movable between a first position in which the second
portions 24A (or at least part of the second portions) engage the
upper surfaces 11B of the first portions 11A, a second position
(following rotation and downward movement of the closure relative
to the container 10), in which the sealing member 23 contacts the
container 10 in a non-sealing position and the second portions 24A
are aligned with spaces between the first portions 11A, and a third
position (corresponding to the position shown in FIGS. 3A and B),
following further rotation and further downward movement of the
closure relative to the container 10, in which the sealing member
23 has been moved downwards to sealingly engage the sealing surface
10C of the container and the second portions 24A are located
beneath the first portions 11A and in contact with substantially
the entire circumferential length of the lower surfaces 11C
thereof.
[0255] Mounting the skirt portion 21 on the container thus involves
the following stages: the second portions 24A are initially located
above the first portions 11A and are then moved so they pass
through the spaces between the first portions 11A and finally to a
position in which they are located beneath the first portions 11A.
The upper surfaces 24B of the second portions 24A are substantially
horizontal and substantially flat throughout their length (or at
least between the inclined ends 24D and 24E of the second portions
24A), so they can slide horizontally beneath the lower surfaces 11C
of the first portions 11A, the lower surfaces 11C also being
substantially horizontal and substantially flat throughout their
length (or at least between the ends 11D and 11E of the first
portions 11A).
[0256] To release the skirt portion 21 (typically following
completion of the closure by the securement of the closing portion
22C to the skirt portion 21) from the secured position, it is
rotated relative to the container 10 so as to disengage the second
portions 24A from the underside of the first portions 11A and is
then moved upwards. In a simple arrangement without further means
to hold the closure in a venting position, the closure can then be
lifted away from the container 10. In other arrangements, further
rotation will be required to in order to release the closure from a
venting position.
[0257] As described above, in the secured position, the second
portions 24A are located beneath the first portions 11A and, to
release the closure it is necessary to move the second portions so
they are aligned with the gaps between the first portions 11A so
they can pass though these gaps. Accordingly, if it is desired to
prevent removal of the closure and/or provide a tamper evident
feature, this can be achieved by inserting a blocking feature (not
shown) into one or more of the gaps between the first portions 11A
to prevent the second portions 24A being moved into alignment with
said gaps and/or pass through said gaps until the blocking feature
has been moved out of the way.
[0258] Such a blocking feature can be provided in a variety of
ways. It may, for example, be attached to the closure or may be
separate therefrom. It may be arranged so that when sufficient
torque is applied thereto it ruptures and/or moves radially
outwards so it no longer blocks movement of the second portion 24A
into alignment with the gaps between the first portions 11A. In
some cases, the blocking feature is positioned such that if the
closure begins to be rotated in the loosening direction, the second
portion 24A engages one side of the blocking features which blocks
further rotation of the second portion 24A. If the blocking feature
has a width similar to the length of the gap between the first
portions 11A, circumferential movement of the blocking feature in
the loosening direction may also be prevented by another side of
the blocking feature engaging an end a first portion 11A.
[0259] Referring back to FIGS. 1A and B, it will be noted that the
first portions 11A have inclined end surfaces 11D and 11E. These
may lie at approximately 45 degrees to the horizontal but shallower
angles in the range 15 to 20 degrees may be used. The end surface
11D may extend from the upper surface 11B to the lower surface 11C.
However, the end surface 11E may not extend all the way from the
lower surface 11C to the upper surface 11B. The end surfaces 11D
and 11E of the first portions may also have other forms.
[0260] FIG. 34 shows a cross-section of a skirt portion 21 of a
closure and container 10 in the secured position. As will be seen,
the o-ring 23 has been driven downwards to sealingly engage the
sealing surface 10C around the exterior of the container. This
involves compression of the o-ring 23 and the above arrangement in
which the downward movement of the closure which causes this is
effected by rotation of the closure provides a significant
mechanical advantage in providing the force required to compress
the o-ring 23, particularly for a wide-mouth closure in which the
closure has a relatively large diameter (eg compared to a bottle
cap).
[0261] As indicated above, the closure is formed from two initially
separate parts: the skirt portion 21 (as shown in FIG. 32) and the
closing portion 22C (as shown in FIG. 35). Both parts of the
closure are preferably formed of metal and can be formed by
pressing and/or rolling operations or other metal forming
techniques. The skirt portion 21 may, for example, have grooves
rolled in its outer surface to form projections 24A on the inner
surface which provide the second portions 24A. The third portions
25A may also be formed by further grooves rolled in the outer
surface to form projections 25A on the inner surface.
Alternatively, the third portions 25A may be formed in the lower
lip of the skirt portion, eg as it is turned upwards to provide a
convex edge (as in conventional metal closures).
[0262] The wall thickness (gauge) of such a metal closure may
typically be in the range 0.14 mm-0.24 mm. The metal used may be
similar to that used in conventional metal closures, eg as used for
other types of twist off caps, for example tinplate (a low carbon
mild steel coated on both surfaces with an electrolytic deposition
of tin). The metal closure may also be formed from aluminium sheet
as used in known aluminium beverage containers and closures, for
example as used for roll on pilfer-proof (ROPP) closures. The use
of aluminium also enables the provision of a tamper evident band on
the closure, for example a drop-band which separates from the
closure as the closure is removed (and which could drop into the
handling groove 15) or a split-band which is ruptured when the
closure is removed and comes away with the closure.
[0263] Similar tamper evident features may be provided in any of
the embodiments described herein.
[0264] Once the skirt portion 21 has been releasably secured on the
container as shown in FIG. 14, the closing portion 22C may be
secured thereto. The closing portion 22C is located onto an
upstanding cylindrical part 21A of the skirt portion so as to close
an opening 21B in the skirt portion 21 as shown in FIG. 36, eg by
locating an angled flange 22D around the periphery of the closing
portion 22C over the cylindrical part 21A of the skirt portion 21.
Flange 22D may then be compressed in a seaming operation to form a
seamed joint with the cylindrical part 21A as shown in the
cross-sectional view in FIG. 37. The closing portion 22C is thus
irreversibly secured to the skirt portion 21 to complete the
formation of the closure. As the skirt portion 21 has already been
releasably secured to the container 10, the completed closure is
formed so it is releasably secured to the container 10. FIG. 38
shows a perspective view of the completed closure secured to the
container as in FIG. 37.
[0265] Other techniques may be used for irreversibly securing the
closing portion 22C to the skirt portion 21, eg gluing or welding
although seaming is preferred when the parts are made of metal as
seaming is a widely used process in the canning industry.
[0266] As previously mentioned, the method described above for
forming a releasable closure allows the skirt portion of the
closure to first be fitted to the container, for the container to
then be filled, eg with a beverage, through the opening 21B in the
skirt portion 21, and the closing portion 22C to then be secured to
the skirt portion 21, ie after the container has been filled. This
novel method of forming the closure enables a novel form of
container and closure to be filled and closed on a conventional can
filling and closing line and enables a novel method of filling a
container to be provided, ie a method in which a skirt portion of
closure is releasably secured to a container prior to the container
being filled and fabrication of the releasable closure completed
(so as to close the container) after the container has been
filled.
[0267] FIGS. 39A, 39B and 39C are cross sectional views of a
further embodiment of a closure formed from two parts. This
embodiment is similar to that shown in FIGS. 32-39A, B and C but
with some minor differences. FIG. 39A shows the skirt part 21
secured to the container 10 in the sealed position prior to the
closing part 22C of the closure being secured to the skirt part 21.
FIGS. 32-39A, B and C illustrated a simple form of seamed join
whereas FIGS. 39A, B and C shows a more conventional double seamed
joint. To form such a joint, the upper end of the cylindrical
portion of the skirt part 21 is typically curved or flared
outwardly as shown in FIG. 39A and in the completed seamed joint
this is folded over so that the upper end of the cylindrical
portion is folded into an inverted U-shape as shown in FIG. 39B.
The flange at the periphery of the closing portion 22C is also
formed into a U-shape which interlocks with the inverted U-shape of
the skirt portion 21. The periphery of the closing portion 22C may
also undergo a further 180 degree bend to form a further inverted
U-shape over the joint as shown in FIG. 39B. This double seamed
joint is well known and commonly used in securing an end to a metal
can. FIG. 43 (described further below) shows an enlarged view of
this type of seamed joint (in this case between the container body
10 and a base portion 16). Such a double seamed joint may be used
in all embodiments in which the closure comprises two parts seamed
together of the base of the container body is closed by a closing
portion seamed thereto.
[0268] FIGS. 39A, B and C also shows another example of a metal
closure fitted to a plastic container 10. It also shows more
clearly the upper end of the external surface of the container
being angled (by about 10 to 30 degrees) to the vertical to provide
a surface 10B corresponding to the lead-in surface of the
embodiments having an internal o-ring seal. The external sealing
surface 10C of the container 10 may be substantially cylindrical
(and thus substantially vertical) but may also, as shown in FIGS.
39A, B and C be at a small angle (typically up to 5 degrees) to the
vertical so the diameter of the sealing surface 10C increases
slightly further away from the mouth of the container. This helps
increase the compression force on the o-ring 23 as the closure
moves downwards relative to the container 10 and helps ensure the
o-ring 23 is compressed so as to form a good seal if there are any
variations in the diameter of the container 10 and/or the skirt
portion 21 of the closure due to manufacturing tolerances or
variation in the circularity of either part.
[0269] FIG. 39B shows the closure in the sealed position on the
container 10 with the o-ring seal 23 engaging the external sealing
surface 10C of the container. When the closure is rotated in the
loosening direction it moves upwards relative to the container (as
described in relation to the earlier embodiments) until upward
movement is arrested by engagement of the third portions 25A of
projections of the closure engage the underside of the first
portions 11A of the container. This is the venting position in
which the o-ring seal 23 engages the inclined surface 10B at the
upper end of the container so the o-ring 23 is no longer compressed
so gas can escape from the interior of the container past the
o-ring 23.
[0270] The container shown in FIGS. 39A, B and C is also shaped to
provide a small shoulder 10D beneath the sealing surface 10C. This
provides a transfer feature to enable the closure to be picked up
by automatic handling machinery.
[0271] As mentioned above, some embodiments seek to provide a
container and closure that is compatible with existing fill and
close lines as used in the canning industry to ensure that the cost
of manufacturing the containers and closures is kept low, and
preferably comparable with existing containers. This also means
that investment in manufacturing equipment, eg for filling and
closing such containers is kept down.
[0272] The embodiments of FIGS. 40 to 43 provide another way of
achieving this by providing a container body with a releasable
closure secured to one end but open at the other end. When the
container body is inverted (so the open end is uppermost) it thus
presents the filling and closing line with an open cylindrical form
which may be identical to the open cylindrical form of the upper
end of a conventional can body and can thus be filled and closed on
a conventional filling and closing line with little or no
modification. Further details of this method of filling the
container are provided in co-pending application GB1601501.8.
[0273] This embodiment thus enables an improved form of container
(ie a with mouth container with a releasable closure and,
optionally, re-sealable closure) to be compatible with existing can
filling and closing lines with little or no modification. This
avoids the need for significant capital investment in new or
extensively modified manufacturing plant and so enables an improved
form of container, such as a beverage container, to be manufactured
without the need for capital investment in new manufacturing
apparatus.
[0274] The closure preferably has a thread form similar to that
described in co-pending GB1413249.2 and as described above in
relation to the earlier embodiments. Other thread forms can be used
(but will not have the additional advantages of those described in
GB1413249.2.
[0275] The closure also preferably has sealing means in the form of
an o-ring as disclosed in WO2011/151630 and in GB1413249.2 and as
described in the earlier embodiments. In some embodiments the
o-ring may engage a sealing surface around the exterior of the neck
portion of the container whereas in other embodiment the o-ring may
engage a sealing surface around an internal surface of the neck
portion of the container.
[0276] It will be appreciated that when the container is filled on
a conventional can filling and closure line (as discussed above),
it is important that a good seal is provided between the skirt
portion of the closure and the container (both during the filling
operation and in the finished closed container). The use of an
o-ring seal is particularly advantageous for providing such a seal
when the container is to contain a carbonated beverage (or other
pressurised contents). Other forms of sealing member for proving a
seal between the closure and the container can be used
(particularly in applications in which elevated pressures within
the container do not need to be catered for).
[0277] FIG. 40 shows an exploded view of an embodiment comprising a
wide mouth container body 10 having first engagement means in the
form of circumferentially spaced apart projections 11A around the
exterior thereof at a first end 10A thereof, a releasable closure
having second engagement means in the form of circumferentially
spaced apart projections 24A around the interior thereof for
releasably mounting on the first end 10A of the container body by
engagement of the first and second engagement means, and a
container closing portion 16 for irreversibly securing to a second
end 10B of the container body 10.
[0278] FIGS. 41A and 41B show perspective views of the exterior and
interior of the releasable closure and the projections 24A thereof.
Further description of the releasable closure will be given
below.
[0279] FIGS. 42A and 42B show perspective and front views of the
container body 10 and the projections 11A thereof. The container
body 10 is illustrated in the upright position, ie with its first
opening 10A uppermost, and the description of the engagement means
and the mounting of the releasable closure thereto is given with
the container body 10 in this orientation.
[0280] The container body 10 is formed of metal and has a first
opening defining an axis A at the first end 10A thereof and first
engagement means towards the first end 10A thereof. The first
engagement means comprises an outwardly projecting first member
around an external surface of the container 10, the first member
comprising a plurality of circumferentially spaced apart first
portions 11A (four in the example shown), each first portion 11A
has an upper surface 11B, a lower surface 11C, a first end surface
11D and a second end surface 11E. The upper surface 11B is
substantially horizontal in the circumferential direction but may
be curved or inclined in the radial direction. The lower surface
11C is also substantially horizontal in the circumferential
direction and, in the embodiment shown, is substantially
horizontal, and substantially flat, in the radial direction. The
first portions have substantially similar shape and function to
those described in earlier embodiments.
[0281] FIGS. 42A and 42B show sectional views of the releasable
closure prior to and after being releasably mounted to the first
end 10A of the container body 10 by engagement of the projections
24A of the closure with the projections 11A of the container body
10. FIGS. 42A and 42B also show an o-ring seal 23 mounted in a
groove 23A in a skirt portion 21 of the closure for providing a
seal between the closure and a sealing surface 10C around the
exterior of the container body 10. The container body 10 and
container closing portion 16 are preferably formed of metal,
although might in some circumstances be formed of other materials,
eg plastic or of a combination of materials. A preferred form of
the invention comprises a metal container with a releasable closure
also formed of metal, although the releasable closure may be formed
of other material, eg a plastics material.
[0282] However, in some applications it may be desirable to have a
plastics container body 10 and a closing portion 16 formed of
metal. A plastic container 10 formed by injection moulding and then
blow moulding may not be suitable for housing a carbonated beverage
which requires pasteurisation as the base of the container may
distort during the process so that it no longer provides a stable
platform on which the container 10 can be stood. During blow
moulding the walls of the container are subject to biaxial
stretching so the material thereof changes from an amorphous form
to a more rigid crystalline structure. The base of the plastic
container may still be amorphous and thus subject to deformation at
elevated temperature and pressure. In such a situation, it may be
desirable to cut off the amorphous end of the blow moulding and
seam a metal closing portion 16 thereto in the manner described
above.
[0283] The closure is releasably secured to the body portion of the
container in essentially the same manner as described in earlier
embodiments.
[0284] Once the closure has been releasably secured to the
container body, the container body can be filled through the second
opening in its second end. This may be done by inverting the
container so the second opening is uppermost and then filling the
container body with a liquid (or other contents). As mentioned
above, this may be done in a conventional can filling line arranged
to fill the container in a non-fobbing manner.
[0285] Once the container has been filled, the second opening can
then be closed by securing a container closing portion thereto.
Preferably, this is carried out in a closing station of a
conventional can filling and closing line. As soon as the container
has been filled, a container closing portion can be secured
thereto, eg by forming a seamed joint therebetween. This may be
similar to the manner in which a top (typically comprising a
ring-pull) is secured to a conventional can body. A container
closing portion 16 is aligned with the second opening of the
container body 10 and a flange around its periphery located onto an
upstanding part of the container body 10. The flange is then
compressed in a seaming operation to form a seamed joint with the
container. The container closing portion 16 is thus irreversibly
secured to the container body 10 to complete the formation of the
container. The container 10 can them be returned to an upright
position and the seamed joint forms a base of the container on
which it can stably stand on a flat surface.
[0286] FIG. 43 is an enlarged cross-sectional view of a double
seamed joint that may be formed between the container body 10 and
the closing portion 16. As mentioned above, this form of joint is
well known and commonly used to secure the top of a can (typically
including a ring-pull or narrow diameter screw threaded closure) to
the upper end of a can body.
[0287] FIGS. 44A-44F show a further embodiment of the invention
similar to that shown in FIG. 11 but with six sets of first and
second portions around the circumference of the container and the
closure. FIG. 44A is a perspective view of the closure mounted on
the container. FIGS. 44B and 44C show the container on its own. The
container is similar to that shown in FIGS. 31A and B, FIG. 34 and
FIGS. 39A and B apart from having six first portions 11A round the
periphery thereof. FIGS. 44D to 44F illustrate the closure which,
again is similar to closure of earlier embodiments, eg those of
FIGS. 31A and B and FIGS. 41A and B apart from having six second
portions 24A and six third portions 25A around the circumference
thereof.
[0288] The first portions 11A and second portions 24A are similar
to those of earlier embodiments (eg as shown in FIGS. 1A and B and
FIG. 33 and in FIGS. 2A and B and FIG. 32) apart from having a
shorter circumferential length. The combined circumferential length
of the lower surfaces 11A and of the upper surfaces 24B of the
substantially horizontal elements of the first and second portions
are however still maximised as is the length of the engagement
therebetween in the closed position.
[0289] The third portions 25A are also similar to those of earlier
embodiments (eg those of FIGS. 2A and B and FIG. 32) but have an
detent 25E at one end thereof which, when the closure is rotated in
the loosening direction, is arranged to engage the end 11D of a
first portion 11A to prevent further rotation in the loosening
direction until the container has vented whereupon the closure can
be pushed downwards slightly relative to the container so as to
disengage the detent 25E from the end 11A so the third portion can
continue to slide beneath the first portion in the loosening
direction.
[0290] As shown in FIG. 44C, the lower surface 11C of the first
portion may be co-planar with the upper surface of the handling
groove 15. However, this need not be the case and in other
embodiments the lower surface 11D may be spaced from the groove
15.
[0291] FIGS. 45A-45C show another embodiment of the invention
similar to that shown in FIGS. 24A and B but without a handling
recess or transfer feature on the container. As shown in FIGS. 45B
and 45C, the inclined surface 10B leads to a substantially
cylindrical surface part of which provides the sealing surface
10A.
[0292] The above embodiments have been described primarily in
relation to applications in which there is an elevated pressure
within the containers, eg if it contains a carbonated beverage.
However, the closure and container may also be used in other
applications in which the pressure within the container is lower
than the pressure outside the container. Such applications include
those in which the container is filled with a hot food product and
the closure then fitted to close the container so that, as the food
cools, the pressure within the container containers falls. In such
applications some variation in the length and/or angle of the parts
of the first and second portions securing the closure to the
container may be desirable. FIGS. 46A, 46B and 46C show schematic
drawings of the first and second portions (six of each in this
example) suitable for a negative pressure application. FIG. 46A the
second portions located beneath the first portions in the closed
position with the substantially horizontal elements engaging each
other. FIG. 46B shows the portions after the closure has been
rotated in the opening direction just before the horizontal
elements disengage from each other. FIG. 46C show the second
portions after they have been rotated further in the loosening
direction and driven upwards relative to the first portions (just
prior to removal of the closure from the container). The first and
second portions interact with each other as in previous embodiments
except that the driving upwards of the closure is against the
negative pressure within the container. In this application, there
is, of course, no need to provide third portions or other provision
for venting excess pressure from the container.
[0293] FIG. 47 is a cross-sectional view of a further embodiment
similar to that of FIGS. 31A and B in which the metal closure has a
plastic component provided on the internal surface thereof. The top
part 20 and skirt part 21 of the closure are formed of metal and
provide the closure with the necessary strength (in particular
against distortion when subject to elevated temperature and
pressure--such as during pasteurisation) and provides the required
gas barrier properties, eg to prevent ingress of oxygen and/or
egress of carbon dioxide (or other carbonating gas). The plastic
component provides the groove for receiving the o-ring seal and the
second and third portions of the threadform used to secure the
closure to the container. The container shown in similar to that
shown in earlier embodiments using a plastic container. The plastic
component may be `over-moulded` to the interior of the metal
component so that it is bonded thereto so the two components
function as a single component. Such a closure may also be used on
containers formed of other materials.
[0294] The closure shown in FIG. 47 has the advantages of both a
metal closure and a plastic closure. The metal part provides
strength and gas barrier properties and the plastic component
provides parts having a more intricate shape which can be more
easily formed, eg by an injection moulding process.
[0295] In all embodiments, the cross-sectional area of the gland is
greater than the cross-sectional area of the o-ring 23 so the
o-ring 23 is able to move and/or deform within the gland (eg as
illustrated in FIGS. 28B and 31A so that it provides a sealing
function as described in WO2011/151630 (rather than simply being a
compression seal which happens to have a circular cross-section).
As described in WO2011/151630, an o-ring 23 located within a gland
provides a very different sealing function to a compression seal.
The o-ring moves and deforms within the gland as the closure is
moved from the position shown in FIG. 28A to the position shown in
FIG. 28B (or from the position shown in FIG. 31B to the position
shown in FIG. 31A). Once in the position shown in FIG. 28B (or FIG.
31A), the o-ring is able to deform further if subject to an
increased pressure differential to further enhance the seal between
the container and the closure. Such deformation of the o-ring (on
fitting of the closure and in response to increases in pressure) is
particularly important when the seal provided by the o-ring needs
to resist relatively high pressure differentials, eg of several
atmospheres (1 atmosphere is approx. 1.times.105 Pascals) when the
container contains a carbonated beverage. In such circumstances (as
described further in WO2011/151630), the compression ratio of the
o-ring is preferably in the range 20-25% and the gland fill in the
range 50-90% and preferably in the range 65-85%.
[0296] As described above the o-ring seal may be provided
internally (as in FIGS. 1A and B to 30A and B) or externally (as in
FIGS. 31A and B-47). In the latter arrangement, as described above,
the o-ring seal may be located in a recess formed in the inner
surface of the skirt portion of the closure and arranged to seal
with an external surface of the container when the closure is
fitted to the container. The recess and o-ring may be similar to
those described in relation to FIGS. 1A and B to 30A and B other
than being provided in the skirt of the cap rather than a bore
component.
[0297] Preferably, the uppermost portion of the external surface of
the container is inclined so as to provide a surface corresponding
to the lead-in surface of the embodiments described above to
compress/deform the o-ring as the closure is drawn downwards
relative the container.
[0298] Such a closure may be also provided with a bore component
that fits within the mouth of the container as described above.
This bore component need not have a recess therein for receiving a
further o-ring (although an internal o-ring as described above
could also be provided in addition to the external o-ring on the
skirt of the closure). A closure with an external o-ring provided
in a recess in the skirt of the cap (as described above) but
without a bore component is also possible.
[0299] The thread features provided on the closure (and the
container) of a closure having such an external o-ring may be
essentially similar and function in a similar manner to those
described above.
[0300] In the embodiments described above the first, second and
third portions are each equi-angularly spaced around the
circumference of the container and closure. However, it would be
possible for these to be non-uniformly spaced, eg if it is desired
to provide a large spacing between the portions in one or more
areas so as to provide a more comfortable are to drink from.
[0301] The illustrated embodiments each have four first portions
(and four second portions and four third portions) but, as
indicated, a smaller or greater number may be used depending on the
diameter of the closure and container and the pressure the closure
is designed to withstand. In some applications, it may be desirable
to provide, for example, six first portions (and six second
portions). Such embodiments may also have six third portions
(although fewer may be used, eg three third portions). Using a
larger number of first and second portions can help provide the
closure with more uniform strength or rigidity around its
circumference which can help minimise the tendency for it to be
distorted into a non-circular shape when subject to high
temperature and pressure (eg during pasteurisation). As shown in
the illustrated embodiments, the first portions all have the same
form and function and, similarly, all of the second portions have
the same form and function.
[0302] The lower surfaces of the first portions and the upper
surfaces of the second portions are, as described preferably
substantially flat in the radial direction. However, in some
embodiments, eg on a bottle neck, these surface may be angle or
curved in the radial direction so long as the interaction between
the surfaces in the vertical direction is sufficient to provide the
required securement of the closure on the container in the vertical
direction.
[0303] In the embodiments described, the first portions preferably
have a simple and relatively smooth shape so as to minimise their
impact on the appearance of the container and their impact on the
user's lips whereas the second (and optionally third) portions on
the closure may have a more complex shape as they do not come into
contact with the users lips and as they are concealed to some
extent on the inner surface of the closure. However, in situations
where these factors are of less concern, the first portion may have
a more complex shape. One possibility is for the downwardly and
upwardly angled ends of the second portions to be provided instead
on the first portions. Another possibility would be for the first
portions to be provided on the closure and the second portions on
the container.
[0304] For carbonated applications in particular, the upwardly
angled ends may also be omitted if the pressure within the
container is relied upon to assist the user in lifting the closure
once the engagement of the third portions beneath the second
portions has been released.
[0305] As described above, the first and second portions of the
thread form for securing the metal closure to the container have
elements with elongate surfaces which are substantially horizontal.
The engagement between upper surfaces of the first portions and
lower surfaces of the second portions secures the closure on the
container and resists upward movement of the closure relative to
the container. The frictional engagement between these surfaces
also resists rotation of the closure in the loosening direction
until sufficient torque is applied to overcome this. In view of the
length of the engagement of these surfaces, this is, in many cases,
sufficient to prevent inadvertent loosening of the closure.
However, in same circumstances it may be desirable to provide some
additional resistance to rotation of the closure in the loosening
direction, eg if the closure is subject to vibration. One way of
achieving this (as shown in FIG. 44A-F) is to provide a detent at
the end of one of the surfaces, eg on one or more of the second
portions, that engages part of a first member so as to inhibit
rotation in the loosening direction but which can be overcome by a
small downward movement of the closure relative to the container
(followed by rotation in the loosening direction). For an
applications in which the internal pressure of the container is
elevated, this may be arranged so that whilst the pressure is
elevated, the detent is held in a position in which it resists
rotation of the closure but, once the excess pressure has been
vented, the closure can be depressed to overcome the action of the
detent.
[0306] Another option is to incline the engaging surfaces slightly,
eg by up to 1-2 degrees, so that in order to rotate the closure in
the loosening direction, the closure has to move downwards slightly
as these (slightly inclined) engaging surfaces slide over each
other. This reverse inclination of surfaces need only be very small
to provide the required resistance to inadvertent loosening of the
closure so the surfaces are still `substantially horizontal`.
[0307] When a metal closure is used on a plastic container, it
remains necessary to maximise the area of contact between the first
and second portions otherwise the pressure on the plastic part
would increase and may thus be deformed. As with a plastic closure,
the circumferential length of the substantially horizontal upper
surfaces of the second portions is preferably at least 50% or at
least 75%, of the circumferential length of the substantially
horizontal lower surfaces of the first portions.
[0308] For a container housing a carbonated beverage, the
circumferential length of the substantially horizontal upper
surfaces of the second portions is preferably substantially the
same as the circumferential length of the substantially horizontal
lower surfaces of the first portions.
[0309] Also, each first portion preferably has a circumferential
length substantially similar to the circumferential length of said
elements of the second portions and preferably said elements of the
second portions are in contact with substantially the entire
circumferential length of said lower surfaces of said first
portions when the closure is secured to the container.
[0310] For a wide-mouth container housing a carbonated beverage,
the combined circumferential lengths of the first portions is
preferably substantially half the outer circumference of the
container at the position at which the first portions are provided
thereon.
[0311] As mentioned above, at least for carbonated applications,
the combined circumferential length of the first portions is
preferably about 50% of the external circumference of the container
and in the secured position the second portions are in contact with
substantially the entire circumferential length of the lower
surfaces of said first portions. For non-carbonated application in
particular, but also when both cap and container are made from a
stronger material such as metal which is less liable to
deformation, the combined circumferential length of the first
portions (and of the second portions) may be less but is preferably
at least 15-25% of the external circumference of the container (or
closure) to help ensure the closure is securely held on the
container (as it may still be subject to a pressure differential
due to temperature changes or to reduced external pressure). Also,
if the gaps between the first portions or second portions become
too large, there is a risk that the closure may distort to a
non-circular shape which can prejudice the seal between the
container and the closure.
[0312] Similarly, the second portions may be in contact with less
than the entire circumferential length of the lower surfaces of
said first portions. However, the length of contact should be
sufficient to enable the surfaces to slide over each other and
sufficient to withstand the pressure to which the closure will be
subjected to without the second portions becoming indented in, or
otherwise damaging, the first portions.
[0313] It will also be appreciated from the embodiments described
above that the circumferential spacing between the first portions
must be sufficient to allow the second portions to pass
therebetween. Although the second portions may have one or more
inclined ends, and these may pass ate an angle between the first
portions, the horizontal elements of the second portions must be
shorter than the circumferential spacing between the first portions
(whether they pass vertically or at an angle through the gaps
therebetween).
[0314] Whilst the closure may initially be applied to the container
my machinery during manufacture or in a closing and filling line,
the ability for the end user to be able to re-close and re-seal the
container after its initial opening is a significant advantage in
many applications. With a wide mouth closure, and particularly when
there is a need to maintain a good seal at elevated temperatures
and/or pressures, the provision of a closure which can also be
easily removed and re-applied manually by the end user and yet
provide a reliable seal can be challenging. The threadform and
sealing arrangements described above provide a solution to
this.
[0315] For the avoidance of doubt, the verb "comprise" as used
herein has its normal dictionary meaning, ie to denote
non-exclusive inclusion. The use of the word "comprise" (or any of
its derivatives) does not therefore exclude the possibility of
further features being included.
[0316] All of the features disclosed in this specification
(including the accompanying claims, and drawings) may also be
combined in any combination (other than combinations where the
features are mutually exclusive).
[0317] Each feature disclosed in this specification (including the
accompanying claims and drawings) may be replaced by alternative
features serving the same, equivalent or similar purpose, unless
expressly stated otherwise. Thus, unless expressly stated
otherwise, each feature disclosed is just an example of a generic
series of features providing an equivalent or similar function.
[0318] The invention is not restricted to the details of the
embodiments described. The invention extends to a container and/or
closure which comprises one or more of the features referred to
above, or any other novel concept, feature, or combination of the
features disclosed herein.
* * * * *