Field of the invention
[0001] The present invention relates to a bottle closure comprising a screw cap and a tamper-evident
rim, and to a plastic bottle provided with such a closure.
Background
[0002] Plastic bottles with screw caps are often used for liquid food products, and in particular,
for liquid food products intended to be consumed on the go, such as carbonated soft
drinks. Due to the high volumes in which such bottles are produced, it is desirable
that the screw cap be produced at low cost and with low environmental impact. For
example, it may be desired that the screw cap be tethered to the bottle to reduce
the risk of loss and littering. Moreover, bottle spouts are highly standardized, and
bottle closure applicator machinery is typically fine-tuned to a specific design of
closures and bottle spouts with high precision. It may therefore also be desired that
the bottle closure be possible to use in existing bottle closure applicator machinery
without modifications thereto. At the same time, the closure should preferably be
easy to use, should not interfere with the stream from the spout while pouring or
drinking, and should work not only in theory but also in practice.
US 2022/0002021 A1 suggests a tethered screw cap configured to be attached to a plastic bottle, and
also addresses the standard PCO 1881. There is however a need for a further improved
screw cap.
Summary
[0003] It is an object of the present invention to solve, or at least mitigate, parts or
all of the above mentioned problems. To this end, according to a first aspect, there
is provided a bottle closure configured to be attached to a bottle spout, the bottle
closure comprising a screw cap and a tamper-evident rim extending axially along a
circular-cylindrical envelope, wherein the screw cap comprises an axial closure wall
configured to close an orifice of the bottle spout, the axial closure wall having
a top face which faces in an upwards axial direction; and a cap skirt extending from
the axial closure wall in a downwards axial direction to a bottom rim of the cap skirt,
the cap skirt being provided with an internal thread configured to engage with an
external thread of the bottle spout by rotating about a screw axis and thereby translate
the screw cap along the screw axis, wherein the bottom rim of the cap skirt extends
about the screw axis along a circumferential screw cap separation line in a plane
perpendicular to the screw axis, the screw cap separation line spanning, in said plane,
an angle of at least 330° about the screw axis, wherein the bottom rim is releasably
connected to the tamper-evident rim via frangible bridge arrangement along the screw
cap separation line, wherein the tamper-evident rim comprises an attachment ring configured
to rotatably and non-detachably engage with the bottle spout, and a single tether
band tethering the screw cap to the attachment ring, wherein the tether band is configured
to, after the frangible bridge arrangement has been broken, be resiliently bent radially
outwards from the screw axis against a bias. Thereby, when unscrewed from the bottle
spout, the screw cap may be twisted about the tether band to a position in which the
top face of the axial closure wall extends along the screw axis and/or axially downwards.
In this position, radial bias of the tether band, generated in the tether band when
resiliently bent radially outwards from the screw axis, will press the cap towards
the bottle, such that a stable position of the cap which does not obstruct the spout
opening of the bottle may be obtained. The circular-cylindrical envelope defines a
cylindrical coordinate system about the screw axis, the coordinate system being anchored
to the bottle spout, and thereby also defines a radial direction, and a circumferential
direction, i.e. azimuth, which may be referred to hereinbelow. Preferably, the bottle
closure is free from any structures extending outside the circular-cylindrical envelope.
This facilitates use of the bottle closure in existing bottle closure applicator machinery
adapted for e.g. untethered screw caps designed for bottle spouts pursuant to PCO
1810 or PCO 1881. Moreover, by arranging the screw cap separation line in a plane
perpendicular to the screw axis, a high geometric similarity with untethered screw
caps is obtained, which minimizes any tooling modifications for producing tethered
screw caps. According to embodiments, the tamper-evident rim may have a smooth radially
outer face, and the cap skirt may have a radially outer face which is provided with
friction ribs extending in the axial direction, parallel to the screw axis. Preferably,
the cap skirt has a uniform axial height along its circumference. Thereby, again,
a high geometric similarity with untethered screw caps may be maintained, which minimizes
modifications to existing machinery for producing and applying bottle closures. Similarly,
and for the same reasons, the tamper-evident rim preferably has a uniform width in
the axial direction along its circumference. The screw cap may extend along a first
axial segment of the circular-cylindrical envelope, and the tamper-evident rim may
extend along a second axial segment of the circular-cylindrical envelope, wherein
the second axial segment does not overlap with the first axial segment. Each of the
attachment ring and the tether band may extend along the circular-cylindrical envelope.
According to embodiments, the tether band may be axially separated from the attachment
ring along a tether band separation line, optionally via one or more frangible bridges.
The frangible bridge arrangement may comprise a plurality of discrete bridges, or
an elongate, continuous bridge which defines a tear line. Preferably, the bottom rim
of the screw cap is integrally formed with the tamper-evident rim and the frangible
bridge arrangement. The attachment ring may be configured to non-detachably mate with
a track extending about the circumference of the bottle spout. For example, a radially
inner face of the attachment ring may be provided with a set of circumferentially
distributed barbs configured to engage with a circumferential bead of the spout. The
barbs may be configured as tabs extending radially inwards, wherein the tabs have
free ends which are configured to flex in the radial direction. A bottom face of the
axial closure wall may be provided with a circular bore seal configured to extend
into the spout and engage with a radially inner face of the spout. According to embodiments,
the screw cap separation line may span an angle of more than 340° about the screw
axis.
[0004] According to embodiments, the tamper-evident rim may comprise a first circumferential
section and a second circumferential section different from said first circumferential
section, wherein the tether band is non-detachably connected to the bottom rim of
the screw cap at a screw cap interface at a first circumferential position, and to
the attachment ring at an attachment ring interface at a second circumferential position
different from said first circumferential position, and extends along the attachment
ring, from the screw cap interface to the attachment ring interface, in a first circumferential
direction along the entire length of said first circumferential section of the tamper-evident
rim. According to embodiments, the tether band may extend monotonously in only one
single circumferential direction, i.e. it may extend circumferentially, from the screw
cap interface to the attachment ring interface, only in said first circumferential
direction. The first circumferential section may correspond to the axial overlap of
the screw cap separation line and the tether band separation line. Preferably, said
first circumferential section spans an angle about the screw axis of between 50° and
90°. Accordingly, the first and second circumferential positions may be separated
by the same angle of between 50° and 90°.
[0005] According to embodiments, the internal thread of the cap skirt is right-handed, such
that the screw cap is configured to be unscrewed in an anticlockwise unscrewing direction
as seen in the downwards axial direction, and said first circumferential direction
is said unscrewing direction. Such a direction of the tether band facilitates breaking
any frangible bridges connected to the tether band when opening the closure. Moreover,
strain exposure to the frangible bridges when applying the closure to the bottle spout
during manufacture will be minimized. Thereby, the frangible bridges may be designed
to have a lower strength, which also facilitates opening. Preferably, the screw cap
may be configured to be twisted about the tether band in an anti-clockwise direction
after opening, as seen from the screw cap towards the screw axis; thereby, the screw
cap will be twisted to a lower overall position on the side of the bottle neck.
[0006] According to embodiments, at least one of the screw cap interface and the attachment
ring interface may have a width in the circumferential direction of less than 6 mm.
Thereby, twisting of the tether band about an axis tangential to the circular-cylindrical
envelope may be facilitated. According to embodiments, said at least one of the screw
cap interface and the attachment ring interface may have a width in the circumferential
direction of more than 1,5 mm; for example, between 1,5 mm and 4,5 mm.
[0007] According to embodiments, at least one of the screw cap interface and the attachment
ring interface may, in a section perpendicular to the screw axis, have a shape which
is not reflection-symmetric about a radial axis. Thereby, bending the screw cap interface
or the attachment ring interface about a bending axis which, initially, extends in
the circumferential direction, will tend to deflect the bending axis from the circumferential
direction as the degree of bending increases. Such a bending axis deflection may increase
the radial bias of the screw cap towards the screw axis when bending said at least
one of the screw cap interface and the attachment ring interface. By way of example,
the cross-sectional shape of said at least one of the screw cap interface and the
attachment ring interface may be the shape of a non-rectangular quadrilateral such
as a non-rectangular parallelogram.
[0008] According to embodiments, the attachment ring and the tether band may together span
a total axial width at the first circumferential section which is substantially the
same as an axial width of the attachment ring at the second circumferential section.
Here, substantially the same should be construed as being between 80% and 120% of
the axial width of the attachment band at the second circumferential section. Said
total axial width may, for example, be between 3,3 mm and 3,8 mm, excluding any circumferentially
intermittent axial support ridges, as the case may be.
[0009] According to embodiments, at said first circumferential section, an axial width of
the tether band differs from an axial width of the attachment ring by less than 40%.
For example, the axial width of the attachment ring may be between 10% and 30% greater
than the axial width of the tether band at said first circumferential section.
[0010] According to embodiments, the tether band may be configured to be separated from
the attachment ring along a tether band separation line defined by a circumferential
separation line section extending in the circumferential direction from the attachment
ring interface to the screw cap interface, and, at the screw cap interface, a transversal
separation line section extending from the circumferential separation line section
to the screw cap separation line. According to embodiments, the circumferential separation
line section extends at or adjacent to the axial centre of the tamper-evident rim.
According to embodiments, the tether band separation line may curve, at the screw
cap interface, towards the screw cap separation line with an outer radius of curvature
of between 0,5 mm and 2 mm. Thereby, a high mechanical strength of the attachment
ring may be obtained.
[0011] According to embodiments, the tether band separation line may extend from the screw
cap separation line to a tether band separation line end wall at the attachment ring
interface, wherein a projection of the tether band separation line end wall on the
circular-cylindrical envelope may have a radius of curvature of between 0,15 mm and
0,60 mm. Thereby, a high mechanical strength of the attachment ring interface may
be obtained.
[0012] According to embodiments, the tether band may have an axial width of between 0,90
mm and 1,45 mm. Such an axial width provides a particularly suitable degree of flexibility
in the axial direction for positioning the twisted screw cap on the side of the bottle
spout. Moreover, the axial width range facilitates twisting the screw cap about the
tether band. According to further examples, the tether band may have an axial width
of between 1,10 mm and 1,30 mm.
[0013] According to embodiments, the tether band may have a radial width of between 0,90
mm and 1,45 mm. Such a radial width provides a particularly suitable degree of resilience
in the radial direction for biasing the screw cap against the bottle spout. According
to further examples, the tether band may have a radial width of between 1,10 mm and
1,30 mm.
[0014] According to embodiments, the tether band may comprise a hinge. A hinge provides
intuitive guidance to the user with regard to how to twist the screw cap. The hinge
may be configured as a living hinge and may, for example, be configured as a bend
indication or dent in the tether band. The hinge may define one of a screw cap interface
and an attachment ring interface.
[0015] According to embodiments, the hinge may be configured to enable the screw cap to,
once unscrewed, be pivoted in relation to the attachment ring about a hinge axis of
the tether band which, at least prior to breaking the frangible bridge arrangement,
is substantially perpendicular to the screw axis. Here, substantially perpendicular
to the screw axis should be construed as being inclined by more than 70 degrees to
the screw axis.
[0016] According to embodiments, a distal end of the tether band may comprise the hinge
and a proximal end of the tether band may be connected to the attachment ring. Here,
the term "proximal end" should be construed as the end connected to the attachment
ring, and the term "distal end" should be construed as the end connected to the screw
cap.
[0017] According to embodiments, the hinge may be defined by a bending indication formed
in a radially outer face of the tether band. Thereby, once the screw cap has been
unscrewed and moved to a radial position where it is free to be twisted about the
tether band, the hinge will facilitate pivoting the screw cap axially downwards, and
to at least some degree resist pivoting the screw cap axially upwards. Such an arrangement
serves to guide the consumer to twist the screw cap in the right direction to correctly
position the screw cap, because the shape of the hinge will make it easier to pivot
the screw cap downwards than upwards about the hinge. According to embodiments, the
hinge may have a width in the radial direction of between 0,5 mm and 0,9 mm.
[0018] According to embodiments, a proximal end of the tether band may have a uniform radial
thickness and be free from any hinge.
[0019] According to embodiments, the tether band may have a length along the circumferential
direction corresponding to an angular distance about the screw axis of between 50°
and 90°. Such a length results in a well-defined and stable position of the twisted
screw cap when opened. For a bottle closure adapted for a PCO 1810 spout, this corresponds
to a length of the tether band, along the circumferential direction, of about 14-25
mm. More preferably, the tether band has a length along the circumference of the circular-cylindrical
envelope corresponding to an angular distance of between 65° and 85°.
[0020] According to embodiments, the attachment ring, the frangible bridge arrangement,
and the tether band may be integrally formed with the screw cap. Thereby, a particularly
well-defined bias of the twisted screw cap, when in the open position, may be obtained.
For example, the attachment ring, tether band and screw cap may be injection moulded.
An exemplary suitable material of the bottle closure is plastic. More detailed examples
of suitable materials for the bottle closure are polypropylene and polyethylene terephthalate.
[0021] According to embodiments, the frangible bridge arrangement may comprise a plurality
of frangible bridges joining the screw cap with the attachment ring.
[0022] According to embodiments, the frangible bridge arrangement may comprise at least
one tether band bridge frangibly joining the tether band with one of the attachment
ring and the bottom rim of the cap skirt. According to embodiments, the frangible
bridge arrangement may comprise frangible bridges joining the tether band with both
of the bottom rim of the cap skirt and the attachment ring. Alternatively, the frangible
bridge arrangement may join the tether band with only one of the attachment ring and
the bottom rim of the cap skirt, i.e. the frangible bridge arrangement may be free
from any tether band bridges frangibly joining the tether band with the other of the
attachment ring and the bottom rim or the cap skirt.
[0023] According to embodiments, said at least one tether band bridge may be positioned
at a respective circumferential position along the tether band, and at the respective
circumferential position, there is no frangible bridge joining the tether band with
the other of the attachment ring and the bottom rim of the cap skirt. By not having
frangible bridges both upwards and downwards from the tether band at the same circumferential
position(s), the axial load on the attachment ring in the circumferential section
shared with the tether band may be reduced when unscrewing the screw cap, which reduces
any stretching of the attachment ring when unscrewing the screw cap. This may be particularly
desirable in combination with a small cross-section of the attachment ring.
[0024] According to embodiments, the frangible bridge arrangement may comprise no more than
three tether band bridges frangibly joining the tether band with any of the attachment
ring and the bottom rim of the cap skirt. Such a number of frangible bridges reduces
any stretching of the attachment ring when unscrewing the screw cap.
[0025] According to embodiments, the tether band may be shaped to have a tensile strength
of at least 12 N. Accordingly, a force exceeding 12 N will be required to tear the
cap from the attachment ring. More preferably, the tether band may be shaped to have
a tensile strength of at least 20 N. By way of example, the tether band may be shaped
to have a tensile strength of between 20 N and 40 N.
[0026] According to embodiments, the tether band may be configured to, after the frangible
bridge arrangement has been broken, be resiliently bent radially outwards from the
screw axis against a bias, directed radially inwards, of between 0,35 N and 1,8 N,
measured at a distal end of the tether band. According to further embodiments, the
bias may be between 0,5 N and 1,5 N.
[0027] According to embodiments, the bottle closure may be injection-moulded of a polymer
material comprising at least 75% polypropylene. Such a material facilitates obtaining
a suitable balance between dimensions and resilience of the tether band.
[0028] According to embodiments, the polymer material may have a flexural modulus exceeding
1,3 GPa, for example between 1,3 GPa and 1,8 GPa. Alternatively or additionally, the
polymer material may have a Young's modulus of between 0,9 and 1,7 GPa.
[0029] According to embodiments, the circular-cylindrical envelope may have an outer diameter
of between 29 mm and 34 mm. For example, the bottle closure may be configured to mate
with a bottle spout pursuant to PCO 1810 or PCO 1881.
[0030] According to embodiments, the circular-cylindrical envelope may have an axial length
of between 15 mm and 25 mm.
[0031] According to a second aspect, there is provided a bottle comprising a bottle closure
as defined hereinabove. According to embodiments, the bottle may be made of polyethylene
terephthalate. The bottle may have a threaded bottle spout, wherein the threads have
an outer, i.e. major, diameter of between 27 mm and 29 mm. For example, the bottle
spout may have a shape pursuant to PCO 1810 or PCO 1881 as defined by the International
Society of Beverage Technologists, ISBT.
[0032] It is noted that embodiments of the invention may be embodied by all possible combinations
of features recited in the claims. Further, it will be appreciated that the various
embodiments described for the bottle closure according to the first aspect are all
combinable with the bottle according to the second aspect, and vice versa.
Brief description of the drawings
[0033] The above, as well as additional objects, features and advantages of the present
invention, will be better understood through the following illustrative and nonlimiting
detailed description of preferred embodiments of the present invention, with reference
to the appended drawings, where the same reference numerals will be used for similar
elements, wherein:
Fig. 1 is a perspective view of a bottle closure attached to the spout of a bottle;
Fig. 2 is a perspective view of the bottle closure of Fig. 1 prior to application
to the bottle spout;
Fig. 3 is a side view of the bottle closure and bottle spout of Fig. 1 after application
to the bottle spout;
Fig. 4 illustrates a section of the bottle closure of Fig. 3, the section taken along
the plane indicated by IV-IV in Fig. 3;
Fig. 5 illustrates a section of the bottle closure of Fig. 3, the section taken along
the plane indicated by V-V in Fig. 3;
Fig. 6 illustrates a section of the bottle closure of Fig. 3 prior to application
to the bottle spout, the section taken along the plane indicated by VI-VI in Fig.
4;
Fig. 7 illustrates a section of the bottle spout and bottle closure of Fig. 3, the
section taken along the plane indicated by VI-VI in Fig. 4;
Fig. 8 is a side view of the bottle closure and bottle spout of Fig. 3 after unscrewing
a screw cap of the bottle closure from the bottle spout;
Fig. 9 is a perspective view of the bottle closure and bottle spout of Fig. 8 after
moving the screw cap to the side of the bottle spout against the bias of a tether
band;
Fig. 10 is a perspective view of the bottle closure and bottle spout of Fig. 9 after
twisting the screw cap about the tether band to a first twisted position; and
Fig. 11 is a perspective view of the bottle closure and bottle spout of Fig. 10 after
twisting the screw cap about the tether band to a second twisted position.
[0034] All the figures are schematic, not necessarily to scale, and generally only show
parts which are necessary in order to elucidate the embodiments, whereas other parts
may be omitted.
Detailed description of the exemplary embodiments
[0035] Fig. 1 illustrates a bottle 10 made of polyethylene terephthalate, as frequently
used for beverages intended for immediate consumption. The bottle 10 comprises a neck
12, an upper end of which defines a bottle spout for pouring or drinking the content
of the bottle 10, and a bottle closure 14 is arranged on the spout. The bottle closure
14 comprises a screw cap 16 and a tamper-evident rim 18, which are integrally formed
in one piece of polypropylene by injection moulding.
[0036] Fig. 2 illustrates the bottle closure 14 and the bottle spout 20 in greater detail,
wherein the bottle closure 14 is illustrated separate from the bottle spout 20. The
screw cap 16 and the tamper-evident rim 18 extend along a common, circular-cylindrical
envelope which is symmetric about a screw axis A. The circular-cylindrical envelope
has an outer diameter of about 32 mm, and the bottle closure 14 has an axial length
of about 20 mm. The bottle spout is shaped pursuant to the PCO 1810 standard as defined
by the International Society of Beverage Technologists, ISBT, and is provided with
a right-handed outer thread 22 having an outer diameter of about 28 mm. Even though
not visible in the view of Fig. 2, the screw cap 16 is provided with an inner right-handed
thread mating with the thread 22 of the bottle spout 20, to enable the screw cap 16
to translate along the screw axis A by rotating on the thread 22 of the bottle spout
20.
[0037] The circular-cylindrical envelope of the bottle closure 14 defines a cylindrical
coordinate system about the screw axis A, with an axial or longitudinal direction
along the screw axis A, a radial direction along a polar axis perpendicularly away
from the screw axis, and a circumferential direction or azimuth perpendicular to the
radial direction and the screw axis, along an angular axis of the cylindrical coordinate
system. The bottle spout 20 is substantially circular-cylindrical, with its axis of
symmetry coinciding with the screw axis A, and has a circular orifice 24 defined by
an axially facing, circumferential rim 26 of the bottle spout 20.
[0038] The screw cap 16 comprises an axial closure wall 28 closing, when the closure 14
is applied to the bottle spout 20, the orifice 24 of the bottle spout 20 in a liquid-tight
manner. The axial closure wall 28 has a top face 28a which faces in an upwards axial
direction, i.e. away from the bottle spout 20. The screw cap 16 further comprises
a cap skirt 30 extending from the axial closure wall in a downwards axial direction
to a bottom rim 32. Circumferentially distributed friction ribs 34, extending in the
axial direction A, cover a radially outer face of the cap skirt 30 and provide a good
grip with the fingers when unscrewing the screw cap 16. The bottle closure is however
free from any structures extending outside the circular-cylindrical envelope, such
that bottle closures 14 of the illustrated type can be efficiently handled in commonly
used screw cap applicator machines without getting entangled with each other.
[0039] The tamper-evident rim 18 comprises an attachment ring 36 configured to non-detachably
engage with the bottle spout 20, and a tether band 38 non-detachably tethering the
screw cap 16 to the attachment ring 36. The bottle closure 14 is applied to the bottle
spout 20 by screwing onto the bottle spout 20 to an axial position where the attachment
ring 36 is trapped in a circumferential track 39 between a lower circumferential collar
40 and an upper circumferential bead 42 of the bottle spout 20. The tamper-evident
ring 18 is axially separated from the screw cap 16 by an upper recess 44, which defines
an upper tear indication for axially separating the screw cap 16 from the tamper-evident
rim 18 when opening the bottle closure 14. The upper tear indication extends in the
circumferential direction along a screw cap separation line S1 in a plane perpendicular
to the screw axis A. Similarly, a lower recess 46 defines a lower tear indication
for axially separating the tether band from the attachment ring 36. The lower tear
indication extends in the circumferential direction along a tether band separation
line in a plane perpendicular to the screw axis A. Apart from the lower recess 46,
the tamper-evident rim 18 has a smooth radially outer face.
[0040] The side view of Fig. 3 is better suited for illustrating certain features of the
bottle closure 14. The screw cap 16 extends along a first, upper axial segment A1
of the circular-cylindrical envelope, and has an axial width H1 of about 15 mm. Similarly,
the tamper-evident rim 18 extends along a second, lower axial segment A2 of the circular-cylindrical
envelope, and has an axial width H2 of about 3,5 mm. The first and second axial segments
A1, A2 do not axially overlap. The tamper-evident rim 18 is axially joined with the
bottom rim 32 of the screw cap 16 via a first set of frangible bridges 48, four of
which are pointed out in the view of Fig. 3. Similarly, the tether band 38 is axially
joined with the attachment ring 36 via a second set of frangible bridges 50; in the
illustrated example, the second set comprises a single frangible bridge 50 only. As
can be seen, none of the frangible bridges 48 of the first set are at the same circumferential
position as the frangible bridge 50 of the second set. While the screw cap 16 is reclosable,
i.e. repeatedly movable between the fully closed position of Fig. 1, in which it closes
the orifice 24 (Fig. 2), and a fully open position allowing a person to drink directly
from the orifice 24, the frangible bridges 48, 50 are broken the first time the screw
cap 16 is opened, and thereby serve as a tamper evidence.
[0041] A non-frangible screw cap interface 52 connects the tether band 38 to the bottom
rim 32 of the screw cap 16 in the axial direction, and a non-frangible attachment
ring interface 54 connects the tether band 38 to the attachment ring 36. Thereby,
the tether band 38 extends from a proximal end 38a at the attachment ring interface
54 to a distal end 38b at the screw cap interface 52. Axial support ridges 56 extend
circumferentially along the upper axial face of the tamper-evident rim 18, facing
the screw cap 16. The axial support ridges 56, which are not joined with the screw
cap 16, support the screw cap 16 such that the risk of damage to the frangible bridges
48, 50 during application of the bottle closure 14 to the bottle spout 20 is reduced.
At the same time, the axial support ridges 56 are intermittently distributed along
the tamper-evident rim 18, and have a radial width which is substantially smaller
than the attachment ring 36 and the tether band 38. As such, they do not considerably
contribute to the mechanical strength or resilience of the attachment ring 36 or tether
band 38.
[0042] When unscrewing the screw cap 16 from the bottle spout 20, the bottom rim 32 of the
screw cap 16 will axially separate from the tether band 38 along the screw cap separation
line S1. It will also axially separate from the attachment ring 36 along the tether
band separation line S2. The tether band separation line S2 comprises a circumferential
separation line section S2a extending in the circumferential direction, in a plane
perpendicular to the screw axis A, from the attachment ring interface 54 to the screw
cap interface 52, and, at the screw cap interface 52, a transversal separation line
section S2b extending from the circumferential separation line section S2a to the
screw cap separation line S1. The circumferential separation line section S2a extends
approximately at the axial centre of the tamper-evident rim 18. At the screw cap interface
52, the tether band separation line S2 curves towards the screw cap separation line
S1 with an outer radius of curvature r of about 1 mm. At the opposite end, i.e. at
the attachment ring interface 54, the tether band separation line S2 has a tether
band separation line end wall 55, wherein a projection of the tether band separation
line end wall 55 on the circular-cylindrical envelope has a radius of curvature of
about 0,3 mm.
[0043] Fig. 4 illustrates a section along the plane indicated by IV-IV in Fig. 3, immediately
above the axial support ridges 56. The screw cap separation line S1 spans an angle
a1 of about 345° about the screw axis, while the screw cap interface 52 represents
the remaining angle a2 of about 15°, corresponding to a width W1 in the circumferential
direction of about 3 mm. The radial width W2 of the tether band 38, as well as of
the attachment ring 36, is about 1,2 mm, while the radial width W3 of the screw cap
attachment interface 52 is about 0,7 mm, i.e. slightly more than half the radial width
W2 of the tether band 38. The reduced material thickness at the screw cap interface
52 forms a bending indication defining a living hinge 53, which will be described
in greater detail further below. The hinge 53 enables the screw cap 16 (Fig. 3) to,
once unscrewed from the bottle spout 20 (Fig. 3), pivot about a hinge axis HA which,
at least for small pivot/bending angles, is substantially perpendicular to the screw
axis A as well as to the radial direction. The bending indication defining the hinge
53 is formed in the radially outer face of the tether band 38. As apparent from the
section of Fig. 4, the hinge 53, which defines the screw cap interface 52, has a cross-sectional
shape which is not reflection-symmetric about a radial axis; more precisely, it has
the general shape of a non-rectangular parallelogram. Thereby, substantial pivoting
of the screw cap 16 downwards about the hinge 53 will tend to shift the pivot axis
HA clockwise, as seen from above. The remaining part of the tether band 38, from the
hinge 53 to the proximal end at the attachment ring interface 54, has a uniform radial
width W2 without any bending indications.
[0044] Frangible bridges 48 and axial support ridges 56 are shaped and positioned to enable
extraction from an injection moulding tool in a tool extraction direction extending
along an extraction line E. One of the frangible bridges 48 is a tether band bridge
48a, which connects the tether band 38 with the bottom rim 32 of the screw cap 16
(Fig. 3).
[0045] Fig. 5 illustrates a section in the plane indicated by V-V in Fig. 3, along the tether
band separation line 46 immediately below the tether band 38 (Fig. 3). Even though
not part of the illustrated section, a broken line indicates the position of the screw
cap interface 52. The tether band 38 (Fig. 3) extends along a first circumferential
section C1 of the tamper-evident rim from a first circumferential position P1, in
an anti-clockwise circumferential direction D, to the attachment ring interface 54
(Fig. 3) at a circumferential position P2. The first circumferential section C1 corresponds
to the axial overlap of the screw cap separation line S1 (Fig. 2) and the tether band
separation line S2 (Fig. 2). The first circumferential section C1 spans an angle about
the screw axis A of about 75°. Thereby, the remaining, second, circumferential section
C2 spans an angle about the screw axis A of about 285°. Accordingly, the axially free,
or at least axially detachable, segment of the tether band 38 spans an angle in the
circumferential direction of about 75° which, for a bottle closure adapted for a PCO
1810 spout, corresponds to a length of the tether band, along the circumferential
direction, of about 21 mm.
[0046] Fig. 5 also illustrates the frangible bridge 50, which is a tether band bridge connecting
the tether band 38 (Fig. 3) with the attachment ring 36.
[0047] Fig. 6 illustrates an axial section taken along the extraction line E of Fig. 4,
the view indicated by VI-VI. The view illustrates the internal thread 58 of the cap
skirt 30, and a bore seal 60 extending axially downwards from the lower face of the
axial closure wall 28. The bore seal 60 is configured to extend, when the bottle closure
14 is tightly screwed to the bottle spout 20 (Fig. 2), into the orifice 24 (Fig. 2)
of the bottle spout 20, and seal against the radially inner wall of the bottle spout
20 in a liquid-tight manner.
[0048] As apparent from the view of Fig. 6, at the second circumferential section C2, the
attachment ring 36 alone represents the total axial width H2 of the tamper-evident
rim 18, whereas at the first circumferential section C1 (see magnified detail), the
tether band 38 and the attachment ring 36 together span the total axial width H2 of
the tamper-evident band 18. At the first circumferential section C1, the axial width
H3 of the tether band 38 is about 1,2 mm, excluding the axial support ridges 56, while
the axial width H4 of the attachment ring 36 is about 1,6 mm.
[0049] The radially inner face of the attachment ring 36 is provided with a set of circumferentially
distributed tabs 62 extending radially inwards. The tabs 62 operate as barbs configured
to, when the bottle closure 14 is applied to the bottle spout 20 (Fig. 2) engage with
the circumferential bead 42 of the spout 20. The tabs 62 have free ends 64 which are
configured to flex radially inwards, such that they can pass the circumferential bead
42 when the bottle closure 14 is screwed onto the bottle spout 20, and thereafter
permanently lock the attachment ring 36 to the circumferential track 39 (Fig. 2).
[0050] The section of Fig. 7, taken along the same plane as that of Fig. 6, illustrates
the bottle closure 14 when applied to the bottle spout 20. The tabs 62 permanently
lock the attachment ring 36 to the bottle spout 20 in the axial direction A, whereas
rotation of the attachment ring 36 in the circumferential direction is permitted.
Hence, the screw cap 16 can be unscrewed by turning about the screw axis A, thereby
breaking the frangible bridges 50, 48 (Fig. 3) between the tether band 38 and the
screw cap 16 as well as the attachment ring 36.
[0051] The tether band 38 has a substantially rectangular cross-section and, as noted hereinabove,
a width W2 (Fig. 4) in the radial direction of about 1,2 mm and an axial width H3
(Fig. 6) of about 1,2 mm. This gives the tether band 38 a tensile strength of about
30 N, such that inadvertent breakage is unlikely.
[0052] Fig. 8 illustrates the closure 14 when the screw cap 16 has been screwed off, having
reached a position immediately above the bottle spout 20. The tether band 38 is just
long enough to enable the screw cap 16 to reach the illustrated axial position. From
the position illustrated in Fig. 8, the screw cap 16 can be moved to the side of the
bottle spout 20 by bending the tether band 38 radially outwards from the screw axis
A, against a radial bias generated by the tether band 38, to the position illustrated
in Fig. 9. Owing to the dimensions of the tether band 38 in combination with the resilient
character of the propylene of the closure 14, in the position of Fig. 9, the tether
band 38 exerts a force on the screw cap 16 of about 1 N, measured at the position
of the hinge 53, towards the cylindrical symmetry axis of the screw cap. While the
position of the screw cap 16 in Fig. 9 is stable, the screw cap 16 is too close to
the orifice 24 of the bottle spout 20 to enable convenient drinking directly from
the bottle. From the position of Fig. 9, the screw cap 16 is configured to be twisted
anti-clockwise about the tether band 38, while also bending the living hinge 53 about
the hinge axis HA, to arrive at the position illustrated in Fig. 10, in which the
top face 28a of the axial closure wall 28 (Fig. 2) is substantially parallel to the
screw axis A. The shape of the hinge 53 and the orientation of the hinge axis HA guides
the user to twist the screw cap 16 in the correct direction. Also in the position
of Fig. 10, bias of the twisted tether band 38 will press the screw cap 16 towards
the bottle spout 20, and in particular, against the circumferential collar 40 (Fig.
2), such that a stable position of the screw cap 16 which does not obstruct the orifice
24 of the bottle spout 20 may be obtained. A final stable position may be obtained
by twisting the screw cap 16 a bit further anti-clockwise about the tether band 38,
to the position of Fig. 11, in which the top face 28a (Fig. 2) of the axial closure
wall 28 (Fig. 2) faces downwards along the screw axis A. Also in the position of Fig.
11, bias of the tether band 38 will press the screw cap 16 against the bottle spout
20 to render the position stable.
[0053] The invention has mainly been described above with reference to a few embodiments.
However, as is readily appreciated by a person skilled in the art, other embodiments
than the ones disclosed above are equally possible within the scope of the invention,
as defined by the appended patent claims.
[0054] In the claims, the word "comprising" does not exclude other elements or steps, and
the indefinite article "a" or "an" does not exclude a plurality.
1. A bottle closure (14) configured to be attached to a bottle spout (20), the bottle
closure (14) comprising a screw cap (16) and a tamper-evident rim (18) extending axially
along a circular-cylindrical envelope, wherein the screw cap (16) comprises
an axial closure wall (28) configured to close an orifice (24) of the bottle spout
(20), the axial closure wall (28) having a top face (28a) which faces in an upwards
axial direction; and
a cap skirt (30) extending from the axial closure wall (28) in a downwards axial direction
to a bottom rim (32) of the cap skirt (30), the cap skirt (30) being provided with
an internal thread (58) configured to engage with an external thread (22) of the bottle
spout (20) by rotating about a screw axis (A) and thereby translate the screw cap
(16) along the screw axis (A), wherein the bottom rim (32) of the cap skirt (30) extends
about the screw axis (A) along a circumferential screw cap separation line (S1) in
a plane perpendicular to the screw axis (A), the screw cap separation line (S1) spanning
an angle (a1) of at least 330° about the screw axis (A), wherein the bottom rim (32)
is releasably connected to the tamper-evident rim (18) via a frangible bridge arrangement
(48) along the screw cap separation line (S1), wherein the tamper-evident rim (18)
comprises
an attachment ring (36) configured to rotatably and non-detachably engage with the
bottle spout (20); and
a single tether band (38) tethering the screw cap (16) to the attachment ring (36),
wherein the tether band (38) is configured to, after the frangible bridge arrangement
(48) has been broken, be resiliently bent radially outwards from the screw axis (A)
against a bias.
2. The bottle closure (14) according to claim 1, wherein the tamper-evident rim (18)
comprises a first circumferential section (C1) and a second circumferential section
(C2) different from said first circumferential section (C1), wherein the tether band
(38) is non-detachably connected to the bottom rim (32) of the screw cap (16) at a
screw cap interface (52) at a first circumferential position (P1), and to the attachment
ring (36) at an attachment ring interface (54) at a second circumferential position
(P2) different from said first circumferential position (P1), and extends along the
attachment ring (36), from the screw cap interface (52) to the attachment ring interface
(54), in a first circumferential direction (D) along said first circumferential section
(C1) of the tamper-evident rim (18), and wherein optionally, the internal thread (58)
of the cap skirt (30) is right-handed, such that the screw cap (16) is configured
to be unscrewed in an anticlockwise unscrewing direction as seen in the downwards
axial direction, and said first circumferential direction (D) is said unscrewing direction.
3. The bottle closure (14) according to claim 2, wherein at least one of the screw cap
interface (52) and the attachment ring interface (54) has a width (W1) in the circumferential
direction of less than 6 mm, and/or at least one of the screw cap interface (52) and
the attachment ring interface (54) has, in a section perpendicular to the screw axis
(A), a shape which is not reflection-symmetric about a radial axis.
4. The bottle closure (14) according to any of the claims 2-3, wherein the attachment
ring (36) and the tether band (38) together span a total axial width (H3, H4) at the
first circumferential section (C1) which is substantially the same as an axial width
(H2) of the attachment ring (36) at the second circumferential section (C2), and/or
wherein, at said first circumferential section (C1), an axial width (H3) of the tether
band (38) differs from an axial width (H4) of the attachment ring (36) by less than
40%.
5. The bottle closure (14) according to any of the claims 2-4, wherein the tether band
(38) is configured to be separated from the attachment ring (36) along a tether band
separation line (S2) defined by a circumferential separation line section (S2a) extending
in a circumferential direction from the attachment ring interface (54) to the screw
cap interface (52), and, at the screw cap interface (52), a transversal separation
line section (S2b) extending from the circumferential separation line section (S2a)
to the screw cap separation line (S1), wherein optionally, the tether band separation
line (S2) extends from the screw cap separation line (S1) to a tether band separation
line end wall (55) at the attachment ring interface (54), wherein a projection of
the tether band separation line end wall (55) on the circular-cylindrical envelope
has a radius of curvature of between 0,15 mm and 0,60 mm.
6. The bottle closure (14) according to any of the preceding claims, wherein the tether
band (38) comprises a hinge (53), wherein optionally, the hinge (53) is defined by
a bending indication formed in the tether band, wherein the bending indication is
preferably formed in a radially outer face of the tether band (38).
7. The bottle closure (14) according to claim 6, wherein the hinge (53) is configured
to enable the screw cap (16) to, once unscrewed, be pivoted in relation to the attachment
ring (36) about a hinge axis (HA) of the tether band (38) which, at least prior to
breaking the frangible bridge arrangement, is substantially perpendicular to the screw
axis (A).
8. The bottle closure (14) according to any of the claims 6-7, wherein a distal end of
the tether band (38) comprises the hinge (53) and a proximal end of the tether band
(38) is connected to the attachment ring (36).
9. The bottle closure (14) according to any of the preceding claims, wherein a proximal
end of the tether band (38) has a uniform radial thickness and is free from any hinge.
10. The bottle closure (14) according to any of the preceding claims, wherein the frangible
bridge arrangement comprises a plurality of frangible bridges (48) joining the screw
cap (16) with the attachment ring (36), and/or wherein the frangible bridge arrangement
comprises at least one tether band bridge (48a, 50) frangibly joining the tether band
(38) with one of the attachment ring (36) and the bottom rim (32) of the cap skirt
(30), wherein optionally, said at least one tether band bridge (48a, 50) is positioned
at a respective circumferential position along the tether band (38), and at the respective
circumferential position, there is no frangible bridge joining the tether band (38)
with the other of the attachment ring (36) and the bottom rim (32) of the cap skirt
(30), and wherein optionally, the frangible bridge arrangement comprises no more than
three tether band bridges (48a, 50) frangibly joining the tether band (38) with any
of the attachment ring (36) and the bottom rim (32) of the cap skirt (30).
11. The bottle closure (14) according to any of the preceding claims, wherein the tether
band (38) is shaped to have a tensile strength of at least 12 N.
12. The bottle closure (14) according to any of the preceding claims, wherein the tether
band (38) is configured to, after the frangible bridge arrangement has been broken,
be resiliently bent radially outwards from the screw axis (A) against a bias, directed
radially inwards, of between 0,35 N and 1,8 N, measured at a distal end of the tether
band (38).
13. The bottle closure (14) according to any of the preceding claims, wherein the attachment
ring (36), the frangible bridge arrangement (48), and the tether band (38) are integrally
formed with the screw cap (16), and/or wherein the bottle closure (14) is injection-moulded
of a polymer material comprising at least 75% polypropylene.
14. The bottle closure (14) according to any of the preceding claims, wherein the circular-cylindrical
envelope has an outer diameter of between 29 mm and 34 mm, and/or the circular-cylindrical
envelope has an axial length of between 15 mm and 25 mm, and/or the tether band (38)
has a length along the circumferential direction corresponding to an angular distance
about the screw axis (A) of between 50° and 90°, and/or the tether band (38) has an
axial width (H3) of between 0,90 mm and 1,45 mm, and/or the tether band (38) has a
radial width (W2) of between 0,90 mm and 1,45 mm.
15. A bottle (10) comprising a bottle closure (14) according to any of the preceding claims.