TECHNICAL FIELD
[0001] This invention relates to a tethered plastic screw stopper.
BACKGROUND
[0002] In the field of liquid packaging, it is very common to seal the aperture of a container
with a stopper, often made from a plastic material. Such container is usually a plastic
or glass bottle, but other materials may be used as well.
[0003] The stopper has a tubular shape closed at its top edge by a top wall. The stopper
comprises a roof attached to a tamper shell through bridges. Bridges are distributed
around the circumference of the roof and the tamper shall. The bridges may be made
when molding the stopper or after through undergoing a cutting step during the manufacturing
process.
[0004] Usually the bottle neck includes outer fixation feature, such as thread(s) for screw
type stopper or annular fixation rings for snap type stopper, to secure the stopper
on the bottle neck.
[0005] For screw type stoppers, the tamper shell comprises inner thread(s) arranged inside
side walls. The bottle neck fixation feature may include outer thread(s). Such combination
of outer and inner thread(s) allows the stopper to be screwed on a bottle neck to
seal it and unscrewed for bottle opening. A snap type stopper may include an inner
annular area and the bottle neck fixation feature may include outer fixation ring,
in order to slot in force the stopper on the bottle neck. A snap type stopper may
include a tamper shell with a movable sealing roof from a closed position to a partial
opening position, and reversely. The roof may be separated upon opening or may be
connected to the tamper shell.
[0006] In a bottle sealing position of the stopper, the tamper shell may be secured around
the bottle neck through inner shell retaining features or through the retaining features
diameter being smaller than a diameter of a tamper shell of the bottle neck.
[0007] The roof may be removable. During bottle opening, the bridges form a weakness line
and may be torn apart from the roof, separating it from the bottle. The weakness line
may be torn when user unscrews the tamper shell of the stopper or when user lifts
the roof by tilting.
[0008] There is a recycling risk with separable roof as consumers may not always screw or
snap back the roof onto the bottle neck once empty. The stopper may be thrown away
as litter or put into the trash bin, or worse make its way into a landfill, which
is not good in view of the environmental considerations.
[0009] One solution includes linking the roof to the tamper shell secured on the bottle
neck, so the roof stays attached to the bottle after bottle opening. Such an attached
stopper may be called a "tethered stopper."
[0010] U.S. Patent No. 9,010,555 teaches a plastic screw stopper including a peripheral strip between a tamper shell
and a roof. Such peripheral strip is linked to the tamper shell through a bottom weakness
line and to the roof through a top weakness line. The bottom weakness line and top
weakness line are parallel and extend across the periphery of the stopper in order
to incorporate one or two hinges in close proximity to each other. When unscrewing
the stopper the bottom weakness line and top weakness line tear apart, but the two
hinges hold the roof on the tamper shell. The roof becomes unmovable and as capable
of toggling around the hinges beside of the stopper secured on the bottle neck.
[0011] U.S. 8,490,805 teaches a plastic screw stopper comprises a helicoidal strip between a tamper shell
and a roof. Such helicoidal strip is obtained by cutting the tamper shell around the
stopper. The outer wall of the tamper shell is placed against a blade and the stopper
is moved in rotation relative to the blade according to an angular stroke greater
than an entire turn or more than 360°. During rotation, the stopper is being moved
in an axial movement relative to the blade. The cut line forms a helicoidal weakness
line which remains attached at one end to the tamper shell and at its opposite end
to the roof after opening.
[0012] Other known art prior art systems include a tethered stopper comprising a spiral
strip. The spiral strip is made during the stopper molding so there is no cutting
or slitting operations. Other known prior art systems includes tethered stoppers comprising
two strips linking the closure shell to the tamper band secured on the bottle.
SUMMARY
[0013] This invention is a tethered plastic screw stopper where its closure shell remains
attached to its tamper band after the bottle is opened by use of a strip made into
the plastic material of the stopper between the tamper band and the closure shell
using a bottom weakness line and a top weakness line. Each strip remains connected
to the tamper band secured on the bottle neck by a least a bottom hinge managed into
the bottom weakness line. The opposite ends of each strip are directly linked to the
closure shell through a junction point.
[0014] The stopper further comprises a specific top weakness line where the junction point
of the strip with the closure shell is located over a bottom bridge located at the
nearest from the bottom hinge(s), so called "nearest bottom bridge" on a side of the
screwing direction of the closure shell.
[0015] Thus, the invention systematically allows the nearest bottom bridge to be broken
due to the junction point location where the closure shell and the strip ends are
upwardly moved the farthest from the tamper band during closure shell unscrewing motion.
A force is applied on the closest bridge due to the specific position of the junction
point of the end of the strip.
DETAILED DESCRIPTION OF THE DRAWINGS
[0016] The figures are not necessarily to scale and some features may be exaggerated or
minimized, such as to show details of particular components. Emphasis is placed on
illustrating the principles of the invention. In the figures, like reference numerals
designate corresponding parts throughout the different views.
Figure 1 is a diagrammatic lateral view of a tethered stopper in a closed position
on a bottle.
Figure 2 is a diagrammatic lateral view similar to Figure 1 during the opening of
the stopper.
Figure 3 is a diagrammatic horizontal cross section view along the bottom weakness
line a tethered stopper.
Figure 4 is a diagrammatic horizontal cross section view along the top weakness line
of the tethered stopper.
DETAILED DESCRIPTION
[0017] As required, detailed embodiments of the present disclosure are disclosed herein.
The disclosed embodiments are merely examples that may be embodied in various and
alternative forms, and combinations thereof. As used herein, for example, exemplary,
and similar terms, refer expansively to embodiments that serve as an illustration,
specimen, model or pattern.
[0018] In some instances, well-known components, systems, materials or methods have not
been described in detail in order to avoid obscuring the present disclosure. Therefore,
specific structural and functional details disclosed herein are not to be interpreted
as limiting, but merely as a basis for the claims and as a representative basis for
teaching one skilled in the art to variously employ the present disclosure.
[0019] Phrasing such as 'configured to' perform a function, including in the claims, can
include any or all of being sized, shaped, positioned in the arrangement, and comprising
material to perform the function.
[0020] Terms indicating quantity, such as 'first' or 'second' are used for exemplary and
explanation purposes and are not intended to dictate the specific ordering of a component
with respect to other components. Terms indicating position such as 'top' or 'bottom'
and 'left' or right' are used for exemplary and explanation purposes with respect
to other components.
[0021] Various embodiments of the present disclosure are disclosed herein. The described
embodiments are merely exemplary illustrations of implementations set for a clear
understanding of the principles of the disclosure. Variations, modifications, and
combinations may be made to the described embodiments without departing from the scope
of the claims. All such variations, modifications, and combinations are included herein
by the scope of this disclosure and the claims.
[0022] This invention relates to a tethered plastic screw stopper 100 for closing a bottle
neck 102. The stopper 100 is integrally made of one plastic piece by a molding fabrication
step. Other parts or elements of the stopper 100 can be further created into the entire
plastic piece through a cutting or slitting step.
[0023] The stopper 100 is a screw type and comprises inner fixation features, such as thread(s),
designed to cooperate with outer complementary fixation features made on the bottle
neck 102.
[0024] In some embodiments, as illustrated in Figures 1 through 4, the screwing direction
of the stopper 100 is typically clockwise and extends from right to left. The screwing
orientation is represented as a directional arrow in Figures 1 through 4. The unscrewing
direction of the stopper 100 oppositely extends relative to the screw direction, so
counterclockwise from left to right. In other embodiments, the screwing direction
can be designed counterclockwise.
[0025] The stopper 100 comprises a closure shell 104 and underneath a tamper band 106. The
tamper band 106 and the closure shell 104 are separably linked together by way of
a strip 108.
[0026] In some embodiments, the stopper 100 includes one strip 108. In other embodiments,
the stopper 100 includes two or more strips 108. For example, the stopper 100 includes
two strips 108 positioned on opposite sides of the stopper 100. The two strips 108
can be positioned in a symmetrical or asymmetrical layout.
[0027] The strip 108 is separably connected to the closure shell 104 through a plurality
of top bridges 112 that form a top weakness line 110. Similarly, the strip 108 is
separably connected to the tamper band 106 through a plurality of bottom bridges 116
that form a bottom weakness line 114.
[0028] The bottom weakness line 114 comprises at least one hinge 118 configured to connect
the strip 108 and the tamper band 106. In some embodiments, the bottom weakness line
114 comprises two hinges 118 where each hinge 118 connects a respective strip 108
to the tamper band 106. The two hinges 118 can be spaced through a hole or a less
thick material managed into the tamper band 106 between the two hinges 118.
[0029] The top bridges 112 and bottom bridges 116 are each configured to be stretched and
ultimately broken when unscrewing the closure shell 104. The top and bottom bridges
112, 116 are regularly or irregularly positioned around the perimeter of the top and
bottom weakness lines 110, 114 respectively. However, at the location of the hinge(s)
118, the top and bottom bridges 112, 116 are not present.
[0030] Each strip 108 comprises an extremity at an end of the top weakness line 110, linking
the strip 108 with the closure shell 104 at a junction point 120. For example, in
the embodiment having two strips 108, there is a junction point 120 at each end of
the top weakness line 110, linking the extremity of each strip 108 to the closure
shell 104.
[0031] The top weakness line 110 is configured in order to form an end 122 of the strip
108 positioned above a bottom bridge 116 located at the nearest to the hinge 118 on
the left side of the hinge considering a clockwise screwing direction of the closure
shell 104. When facing the stopper looking at the hinge(s) 118, if the screw direction
is clockwise, then the junction point of the left strip relative to the hinge 118
is located over the nearest left bottom bridge 116 (denoted with parallel vertical
lines in Figure 2).
[0032] The end of the top weakness line located on the left of the hinge 118 for a clockwise
screwing stopper is angularly located between - 40° to 40° relative to the vertical
axis of the bottom bridge 116 located at the nearest from the hinge 118. In some embodiments,
the hinge 118 is more particularly located between - 20° to 20° relative to the vertical
axis of the bottom bridge 116 located at the nearest from the hinge 118. For example,
when looking at the hinge 118, the junction point 120 of the left strip 108 is angularly
situated approximately 20° relative to the left nearest bottom bridge 116. Such angular
variation is shown in the drawings illustrated in dotted lines on Figures 3 and 4.
[0033] In some embodiments, the top weakness line 110 is asymmetric relative to the bottom
weakness line 114 which is symmetric relative to a vertical plane crossing the diameter
of the stopper 100. So when molding or further slitting the stopper 100, the top weakness
line 110 is angularly switched or turned offset in relation with the position of the
hinge(s) 118 of the bottom weakness line 114. Thus, one strip 108 (e.g., the left
strip) in a clockwise screwing configuration, is shorter than the opposite strip 108
(e.g., the right strip). In other embodiments, such as show in Figure 3, the bottom
weakness line 114 is symmetric relative to a vertical plane crossing the diameter
of the stopper 100 where the plane being shown by a fine continuous line.
[0034] While various embodiments of the invention have been described, it will be apparent
to those of ordinary skill in the art that many more embodiments and implementations
are possible that are within the scope of this invention.
1. A tethered plastic screw stopper, comprising:
a closure shell;
a tamper band separably connected to the closure shell by a plurality of bridges that
connect a bottom edge of the closure shell to a top edge of the tamper band, each
of the bridges configured to be stretched and broken when the closure shell is moved
from a first orientation prior to opening to a second orientation after opening;
a strip connected to the closure shell at a junction point, the strip comprising an
extremity at an end of the top weakness line positioned above a first set of bridges
located along the bottom weakness line; and
a hinge linking the strip and the tamper band, the hinge being positioned beneath
a set of bridges located along the top weakness line.
2. The tethered plastic screw stopper according to claim 1, wherein considering a clockwise
screwing motion stopper configuration, the end of the top weakness line located to
the left of the hinge of the stopper is located over a bottom bridge of the bottom
weakness line located at the nearest from the hinge relative to the clockwise screwing
direction.
3. The tethered plastic screw stopper according to claim 1, wherein the end of the top
weakness line is located on the left of the hinge and is angularly positioned within
40° of the vertical axis of the bottom bridge located at the nearest from the hinge
considering a clockwise screwing motion configuration.
4. The tethered plastic screw stopper according to claim 1, wherein the end of the top
weakness line is located on the left of the hinge and is angularly positioned within
20° of the vertical axis of the bottom bridge located at the nearest from the hinge
considering a clockwise screwing motion configuration.
5. The tethered plastic screw stopper according to claim 1, wherein the top weakness
line is asymmetric relative to the bottom weakness line which is symmetric relative
to a vertical plane crossing a diameter of the stopper.
6. The tethered plastic screw stopper according to claim 1, wherein:
the strip is a first strip,
the screw stopper further comprises a second strip having extremity at an end of the
top weakness line, linking section the strip with the closure shell at a second junction
point,
the second strip is separably connected to the closure shell through a top weakness
line and to the tamper band through a bottom weakness line and the second strip is
positioned opposite the first strip about a diameter of the tamper band.