U.S. patent application number 10/467574 was filed with the patent office on 2004-06-24 for tamper-evident lid assembly.
Invention is credited to Marshall, Neil R.
Application Number | 20040118848 10/467574 |
Document ID | / |
Family ID | 9921961 |
Filed Date | 2004-06-24 |
United States Patent
Application |
20040118848 |
Kind Code |
A1 |
Marshall, Neil R |
June 24, 2004 |
Tamper-evident lid assembly
Abstract
A lid assembly comprising a lid portion and a frame portion, one
said portion being adapted to receive the other portion to seal a
container fitted with the lid assembly wherein the receiving
portion has tamper-evident means connected thereto as a frangible
bridge while the other portion has a hinged tab and wherein, in the
untampered state, the frangible bridge is intact and prevents
rotation of the hinged tab while, on breaking the frangible bridge,
the hinged tab is able to rotate about its hinge, allowing opening
of the lid.
Inventors: |
Marshall, Neil R;
(Hampshire, GB) |
Correspondence
Address: |
HODGSON RUSS LLP
ONE M & T PLAZA
SUITE 2000
BUFFALO
NY
14203-2391
US
|
Family ID: |
9921961 |
Appl. No.: |
10/467574 |
Filed: |
January 22, 2004 |
PCT Filed: |
September 12, 2002 |
PCT NO: |
PCT/GB02/04156 |
Current U.S.
Class: |
220/266 ;
220/835 |
Current CPC
Class: |
B65D 43/169 20130101;
B65D 2543/00148 20130101; B65D 2401/10 20200501; B65D 2543/00546
20130101; B65D 55/024 20130101; B65D 2543/00027 20130101; B65D
2543/00472 20130101; B65D 2543/005 20130101; B65D 2251/1066
20130101; B65D 2251/105 20130101 |
Class at
Publication: |
220/266 ;
220/835 |
International
Class: |
B65D 041/32; B65D
043/14 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 12, 2001 |
GB |
0122044.1 |
Claims
1. A lid assembly comprising a lid portion and a frame portion, one
said portion being adapted to receive the other portion to seal a
container fitted with the lid assembly wherein the receiving
portion has tamper-evident means connected thereto as a frangible
bridge while the other portion has a hinged tab and wherein, in the
untampered state, the frangible bridge is intact and prevents
rotation of the hinged tab while, on breaking the frangible bridge,
the hinged tab is able to rotate about its hinge, allowing opening
of the lid.
2. A lid assembly according to claim 1 comprising a lid portion
having a hinged tab and a frame portion adapted to receive said lid
portion to seal a container fitted with said lid assembly; said
frame portion having tamper-evident means connected to the frame as
a frangible bridge wherein, in the untampered state, the frangible
bridge is intact and prevents rotation of the hinged tab, and
wherein, on breaking the frangible bridge, the hinged tab is able
to rotate about its hinge, allowing opening of the lid.
3. A lid assembly according to any preceding claim wherein the
frangible bridge is formed between the frame and a detent tab, the
detent tab extending across at least a part of the hinged tab and
preventing rotation of the hinged tab.
4. A lid assembly according to any preceding claim wherein the
frame is provided with retention means which, in the untampered
state, engage the hinged tab, the retention means and the hinged
tab cooperating to prevent upward movement of the hinged tab and
removal of the lid.
5. A lid assembly according to claim 4 wherein the hinged tab is
provided with projections which engage the retention means and
prevent upward movement of the hinged tab.
6. A lid assembly according to any preceding claim wherein the
frame portion is provided with an upturned skirt along at least
part of its periphery, and the lid portion is provided with a
downturned rim, the upturned skirt preventing access to at least a
portion of the downturned rim so that the lid cannot be opened
unless the frangible bridge is broken.
7. A lid assembly according to any preceding claim wherein the lid
portion and the frame portion are connected via at least one
hinge.
8. A lid assembly according to claim 7 wherein the at least one
hinge is provided by a strip of plastics material.
9. A lid assembly having a tamper-evident seal according to any
preceding claim, which also includes retention means; wherein, in
the untampered state, the tamper-evident means and the retention
means engage the hinged tab to prevent rotation of the hinged tab
and removal of the lid, and wherein, in the tampered state, the
frangible bridge has been broken and the hinged tab can rotate
about its hinge and disengage the retention means, allowing opening
of the lid.
10. A lid assembly according to any preceding claim wherein the
detent tab is connected to the frame by a hinge distal to the
frangible bridge.
11. A lid assembly according to any preceding claim wherein the
retention means is connected to the frame by a hinge.
12. A lid assembly according to any preceding claim wherein the
frame is provided with fastening means for fastening the detent tab
to the frame following breaking of the frangible bridge.
13. A lid assembly according to any preceding claim wherein, in the
untampered state, the hinged tab is held between and in register
with the retention means and the detent tab, the hinged tab,
retention means and detent tab being substantially parallel to each
other.
14. A lid assembly according to any preceding claim wherein, in the
untampered state, the hinged tab is substantially orthogonal to the
plane of the lid and substantially parallel to the wall of the
container to which the lid assembly is fitted, and wherein, on
breaking the frangible bridge, the hinged tab can rotate to lie
substantially in the plane of the lid.
15. A lid assembly according to any of claims 1 to 8 wherein the
detent tab is connected to the frame by a bridge which is frangible
at both ends.
16. A lid assembly according to claim 15 wherein the retention
means is connected to the detent tab.
17. A lid assembly according to claim 15 or claim 16 wherein, in
the untampered state, the hinged tab is held by the retention means
behind, substantially parallel to and in register with, the detent
tab.
18. A lid assembly according to claim 15, 16 or 17 wherein the
retention means maintain the detent tab fastened to the hinged tab
following breakage of the frangible bridge.
19. A lid assembly according to any preceding claim which is
injection moulded from a plastics material.
20. A lid assembly according to any preceding claim wherein the
frame portion can be secured to the rim of a container in a snap
fit manner.
21. A lid assembly according to any preceding claim wherein the lid
is provided with retainer means for releasably engaging the hinged
tab and retaining the hinged tab in a configuration substantially
orthogonal to the plane of the lid.
22. A container provided with the lid assembly of any of claims 1
to 21.
23. A lid assembly according to any preceding claim wherein the
frame portion is an integral part of the container to be
sealed.
24. A lid assembly as hereinbefore described with reference to any
of the accompanying Figures.
25. Use of a container comprising a lid assembly which includes a
lid portion and a frame portion, the lid portion and the frame
portion being connected by at least one hinge, for containing
yellow or edible fats such as margarine or spreadable butter.
26. Use of a container according to claim 25 wherein the container
is defined in claim 22.
27. A container comprising a receptable with a rim, the rim
including a plurality of spaced apart interference means and a lid
assembly comprising a lid portion and a frame portion, the frame
portion cooperating with the rim and including a plurality of
spaced apart interference means which are in register with those on
the rim and which cooperate therewith to reduce slack between the
frame and the receptable.
28. A container according to claim 27 provided with the lid
assembly of any of claims 1 to 21.
Description
[0001] The invention relates to lid assemblies for containers.
Specifically, the invention relates to lid assemblies having
tamper-evident seals.
[0002] Containers having tamper-evident seals are known for the
storage of many substances such as comestibles and chemicals.
Tamper-evident means on such containers are required in order to
show the purchaser that the substance inside the container has not
been exposed to the outside environment and/or contaminated
following packaging. Community legislation now enforces the
provision of tamper-evident means on many classes of container.
[0003] The tamper-evident means can take a wide variety of forms,
for example a lid which is connected to a container via a tear
strip, such that the lid cannot be removed unless the tear strip is
first removed by the user. Once the tear strip is removed, it
cannot be re-attached, and the user will thus know that the lid has
been opened following initial filling of the container. Other
tamper-evident means comprise a lid connected to a collar around
the container by a number of frangible bridges. When the lid is
first removed by the user (usually by rotating the lid relative to
the container), the frangible bridges are broken, and once broken
they cannot subsequently be re-formed. Thus, the user can tell
prior to purchase whether the lid has been removed from the
container following initial filling of the container.
[0004] Further tamper-evident means comprise a removable flange
extending from and attached to the lid by frangible bridges, and
also being connected to a collar around the container via frangible
bridges. The collar extends around the rim of the lid, preventing
access to the rim in the untampered state. The collar and the lid
are not connected to each other apart from by the removable flange.
In order to open the container, the frangible bridges connecting
the removable flange to both the lid and the collar are broken, and
the removable flange is thus detached from the container. the user
can then access the rim of the lid and prise the lid from the
container. If the container has been tampered with following
initial filling, this will be obvious because the removable flange
will be missing.
[0005] Following breakage of the tamper-evident means (e.g. the
tear-strip or the frangible bridges connecting the collar and lid
or the collar, lid and removable flange) the user must then open
the container, usually by prising the rim of the lid away from the
rim of the container. Removal may be difficult to achieve if the
user has reduced dexterity, and such containers can lead to people
breaking fingernails when attempting to access the rim of the lid.
In order to ameliorate this problem, it has previously been
desirable to provide the lid with a rigid flange, extending
outwards from the lid. The flange has a larger surface area than
the rim of the lid and the user can grip this flange to aid in
removal of the lid.
[0006] However, there are problems associated with providing such
flanges. First, the flanges may have a tendency to break
unintentionally For example, the flanges may break during rough
handling, transit or during use in removal of the lid, and
subsequent removal of the lid following such breakage may be
difficult. Secondly, the flanges can disrupt optimal close-packing
of the containers. For example, if the containers are generally
cuboid in shape, the provision of a flange on the corner of the lid
means that the containers cannot pack in such a close arrangement
as if the flange were not present. Thirdly, presence of a flange
may make provision of the tamper-evident means more difficult. This
is because the flange will result in the lid of the container
having an irregular shape, and may therefore mean that more complex
tooling is required to provide a tear-strip or collar.
[0007] It is an object of this invention to provide an improved lid
assembly having tamper-evident means, and which provides means for
easy removal of the lid following removal or breakage of the
tamper-evident means.
[0008] According to a first aspect of the invention there is
provided a lid assembly comprising a lid portion and a frame
portion, one said portion being adapted to receive the other
portion to seal a container fitted with the lid assembly wherein
the receiving portion has tamper-evident means connected thereto as
a frangible bridge while the other portion has a hinged tab and
wherein, in the untampered state, the frangible bridge is intact
and prevents rotation of the hinged tab while, on breaking the
frangible bridge, the hinged tab is able to rotate about its hinge,
allowing opening of the lid; more specifically, there is provided a
lid assembly comprising a lid portion having a hinged tab and a
frame portion adapted to receive the lid portion to seal a
container fitted with the lid assembly, the frame portion having
tamper-evident means connected to the frame as a frangible
bridge.
[0009] In the untampered state, the frangible bridge is intact and
prevents outward rotation of the hinged tab. When the container is
the subject of tamper, the frangible bridge is broken and the
hinged tab is able to rotate about its hinge, allowing opening of
the lid. The frangible bridge may be formed between the frame and a
detent tab provided as part of the frame, such that the detent tab
extends across at least a part of the hinged tab and prevents
rotation of the hinged tab.
[0010] In a preferred embodiment, the lid assembly is provided with
retention means which, in the untampered state, engages the hinged
tab. The retention means and the hinged tab cooperate to prevent
upward movement of the hinged tab and removal of the lid. In order
to achieve this, the hinged tab may optionally be provided with
projections which engage the retention means and prevent upward
movement of the hinged tab.
[0011] In a further embodiment of the invention, it is preferred
that the frame portion is provided with an upturned skirt along at
least part of its periphery, and that the lid portion is provided
with a downturned rim. When the lid is closed, the upturned skirt
prevents access to at least a portion of the downturned rim so that
the lid cannot be opened unless the frangible bridge is broken. By
preventing access to the rim of the lid the user is unable to prise
the lid open. It is preferred that the downturned rim forms the
outer wall of a channel on the lid, the channel being adapted to
fit over the frame and hence seal the container. This arrangement
has the advantage that, when the lid is closed and the channel is
fitted over the frame, horizontal movement of the lid relative to
the frame is prevented.
[0012] The lid portion and the frame portion may be two separate
entities. Alternatively, the lid portion and the frame portion may
be connected by at least one hinge, the hinge being made from any
suitable material, but preferably being composed of a plastics
material.
[0013] According to a second aspect of the invention there is
provided a lid assembly as defined herein which also includes
retention means. In the untampered state the tamper-evident means
and the retention means engage the hinged tab to prevent rotation
of the hinged tab and removal of the lid. In the tampered state,
the frangible bridge has been broken and the hinged tab can rotate
about its hinge and disengage the retention means, allowing removal
of the lid.
[0014] The detent tab may be connected to the frame via a hinge,
the hinge being located distal to the frangible bridge, preferably
at the opposite end of the detent tab to the hinge.
[0015] The retention means may be a retention flap which may be
connected to the frame by a hinge. A hinged retention flap has the
advantage that, once the lid assembly is in place on a container,
the container rim contacts the retention flap, pushing it outwards
against the hinged tab. By pushing the retention flap and the
hinged tab together this in turn pushes the hinged tab against the
detent tab. This arrangement prevents any movement of the hinged
tab (either rotational or translational) and hence makes it
impossible to open the lid without first breaking the frangible
bridge.
[0016] Further suitable features, which can each be used in
conjunction with the several aspects of the invention described
above, will now be described. The frame may be provided with
fastening means for fastening the detent tab to the frame following
breaking of the frangible bridge, with the fastening means
preferably taking the form of a fastening stud. The stud can
frictionally engage a hole which may be provided on the detent tab,
hence holding the detent tab in place once the frangible bridge has
been broken and the detent tab has rotated away from the hinged
tab.
[0017] A preferred configuration of both aspects of the lid
assembly is where, in the untampered state, the hinged tab is held
between and in register with the retention means such as a flap and
the detent tab. The hinged tab, retention means and detent tab are
thus held in a substantially parallel arrangement.
[0018] Another desirable feature is where, in the untampered state,
the hinged tab is substantially orthogonal to the plane of the lid
and substantially parallel to the wall of the container to which
the lid assembly is fitted. On breaking the frangible bridge, the
detent tab rotates away from a position preventing access to the
hinged tab, and the hinged tab can rotate to disengage the
retention flap and to lie substantially in the plane of the lid.
The hinged tab thus acts as a flange which the user can grip and
which aids in the opening of the lid. An advantage of this
configuration is that, in the untampered state the hinged tab does
not extend outwards from the lid, unlike the rigid flanges
described in relation to prior art containers.
[0019] In a preferred aspect of this invention, the lid assembly of
the invention is one wherein the detent tab is connected to the
frame by a bridge which is frangible at both ends. In a preferred
embodiment the retention means may be connected to the detent tab,
preferably as at least one integrally formed retention strut.
[0020] A preferred lid assembly according to the invention is one
wherein, in the untampered state, the hinged tab is held by the
retention means such as a retention strut so that the hinged tab is
behind, substantially parallel to and in register with, the detent
tab. It is particularly preferred that retention means such as a
retention strut maintain the detent tab fastened to the hinged tab
following breakage of the frangible bridge.
[0021] By maintaining the hinged tab in a position where it is
substantially parallel to the container walls the containers having
the present lid assemblies can be packed closer together than if
the tab were simply a rigid tab extending outwards from, and being
in the same plane as, the lid.
[0022] Furthermore, by allowing the hinged tab to hinge from being
substantially parallel to the container to being substantially
planar with the rest of the lid, the tab can be made larger than
was previously possible. this is because, in its stored position,
the tab size is limited only by the size of the side wall of the
container. There is no need to make the tab smaller in order to
allow closer packing of the containers, as was the case with prior
art containers because, in the closed position, the tab does not
extend outwards from the plane of the lid. A larger tab is more
user-friendly, providing a larger surface area for the user to grip
when removing the lid.
[0023] This arrangement also has the advantage that once the lid
has been opened and some of the contents removed, the user can then
close the lid and rotate the hinge back to its position
substantially parallel to the container wall. Again, the container
will then occupy less space than prior art containers having a
rigid opening flange.
[0024] In a preferred embodiment, the lid portion is provided with
retainer means which, when the lid is closed and the hinged tab is
in a stored position (i.e. a configuration where the hinged tab is
substantially orthogonal to the plane of the lid and substantially
parallel to the container wall), retain the hinged tab in this
stored position. The retainer means can take the form of one or
more projections extending from the rim of the lid which releasably
engage the hinged tab and retain it in the stored position.
Alternatively, the hinged tab itself may be provided with one or
more projections which releasably engage the downturned rim of the
lid. In both cases, once the tamper-evident means have been broken
and the lid opened, the lid can then be shut and the hinged tab
retained in the stored position by the retainer means. This has the
advantage that in the stored position the hinged tab does not
extend outwards in the plane of the lid, and the container thus
occupies less space.
[0025] The frame portion can be provided with many other features,
such as stacking bumps on the inner wall. These stacking bumps make
it easier to initially stack a plurality of the lid assemblies, and
also allow for easy separation of a stack of the lid assemblies by
an automated packing line.
[0026] If the lid portion and the frame portion are connected, it
is preferred that they are moulded as a single unit from plastic.
If a plastic material is used to form the lid assembly, it can by
any material suitable for moulding (especially injection moulding).
Polypropylene is a particularly preferred material.
[0027] An advantage of a hingeing lid assembly as described above
is that, post forming, the lid assembly may be assembled by
mechanical means, for example by robotic means, or by an off line
handling system. In this way, the lid assembly is assembled into
the fully closed, tamper-evident condition and may then be stacked,
for example, in a box on a pallet.
[0028] The lid assembly can then be transported to the filling
factory and can be magazine fed in its fully closed, tamper-evident
condition. After the container to which the lid assembly is to be
fitted has been filled, the lid assembly can either be place on the
container by hand or by machine, and is then subjected to a
downward force which clips the lid assembly onto the container.
[0029] During forming of the lid assembly, the hinged tab
preferably lies in the same plane as the rest of the lid portion.
However, prior to the lid assembly being closed the hinge may be
worked in order to improve performance. Working the hinged tab may
comprise rotating it, preferably robotically, about its hinge from
a position in which it lies substantially in the same plane as the
rest of the lid to a position in which it is substantially
orthogonal to the plane of the lid. Once the container has been
filled and as the lid and frame are brought together in order to
form the tamper-evident seal, the hinged tab is preferably
substantially orthogonal to the plane of the lid.
[0030] The frame can be secured to the rim of the container to be
sealed by any suitable means. However, it has been found that the
most preferably arrangement is to have the frame secured to the rim
of a container in a snap fit matter. To achieve this, the frame
portion may be provided with retention lugs which engage the rim of
the container to be sealed, and which prevent the lid assembly from
being removed from the container without the application of
force.
[0031] The frame portion may also be provided with retention
features which remove any slack between the container and the lid
assembly. These retention features preferably take the form of
small raised projections extending from the frame portion.
[0032] In a further embodiment, the frame portion may be an
integral part of the container to be sealed. Thus, the rim of the
container can be formed having the configuration of the frame
portion as described above. The lid is then provided as a separate
entity.
[0033] Once the container has been filled with the substance it is
to hold, the lid can then be attached to the container, for example
by means of ultrasonic sealing, heat sealing, for example of a
peripheral bead, one way studs or adhesives.
[0034] The present lid assembly is suitable for use in conjunction
with many different types and sizes of containers, but has been
found to be particularly useful for sealing containers for
comestibles, such as spreads or ice-cream. The lid assembly can be
adapted to seal such containers having a variety of shapes and
volumes, but is particularly suited for sealing containers having a
generally rectangular opening and having a volume of between 1 and
5 litres, preferably approximately 2 litres.
[0035] The invention will now be described, by way of example, with
reference to the accompanying drawings, in which:
[0036] FIG. 1 is a top plan view of the lid assembly of the present
invention with the lid closed and the tamper-evident means in their
untampered state;
[0037] FIG. 2 is a front view of the lid assembly of FIG. 1 when in
place on a container;
[0038] FIG. 3 is a section on line C-C in FIG. 1;
[0039] FIG. 4 is a detail of FIG. 3;
[0040] FIG. 5 is a section on line F-F in FIG. 1;
[0041] FIG. 6 is a side view of the lid assembly and container of
FIG. 1;
[0042] FIG. 7 is a detail of FIG. 5;
[0043] FIG. 8 is a perspective view of the lid assembly and
container shown in FIGS. 1 to 7;
[0044] FIG. 9 is a detail of FIG. 8;
[0045] FIG. 10 is a section on line C-C of FIG. 1 showing an
alternative seal design;
[0046] FIG. 11 is a detail of FIG. 10;
[0047] FIG. 12 is a section on line F-F of FIG. 1 showing an
alternative seal design;
[0048] FIG. 13 is a top plan view of the lid assembly of the
present invention in place on a container with the lid open and the
tamper-evident means in their untampered state;
[0049] FIG. 14 is a front view of the lid assembly and container as
shown in FIG. 13;
[0050] FIG. 15 is a section on line F-F in FIG. 13;
[0051] FIG. 16 is a section on line C-C in FIG. 13;
[0052] FIG. 17 is a side view of the lid assembly with the lid open
and the tamper-evident means in their untampered state;
[0053] FIG. 18 is a detail of FIG. 16;
[0054] FIG. 19 is a perspective view of the lid assembly and
container as shown in FIG. 13;
[0055] FIG. 20 is a detail of FIG. 19;
[0056] FIG. 21 is a top plan view of a lid assembly of the present
invention in place on a container with the lid closed and the
tamper-evident means in their tampered state;
[0057] FIG. 22 is a front view of the lid assembly and container as
shown in FIG. 21;
[0058] FIG. 23 is a side view of the lid assembly and container as
shown in FIG. 21;
[0059] FIG. 24 is a perspective view of the lid assembly and
container as shown in FIG. 21;
[0060] FIG. 25 is a detail of FIG. 24;
[0061] FIG. 26 is a perspective view of the lid assembly of the
invention, with the lid open and the tamper-evident means in their
untampered state;
[0062] FIG. 27 is a detail of FIG. 26;
[0063] FIG. 28 is a section of the lid assembly in place on a
container, showing an alternative seal design;
[0064] FIG. 29 is a bottom perspective view of the lid assembly
shown in FIG. 28 showing detail of the alternative seal design;
[0065] FIG. 30 is a perspective view of a detail of the lid
portion;
[0066] FIG. 31 is a perspective view of a second embodiment of the
lid assembly of the present invention in place on a container with
the lid open and the tamper-evident means in their untampered
state;
[0067] FIG. 32 is a front perspective view of the second embodiment
as shown in FIG. 31 but with the lid rotated on its hinges almost
to a closed position;
[0068] FIG. 33 is a front elevation of the second embodiment as
shown in FIG. 31 but with the lid closed;
[0069] FIG. 34 is a top plan of the second embodiment as shown in
FIG. 33;
[0070] FIG. 35 is a rear elevation of the second embodiment as
shown in FIG. 33;
[0071] FIG. 36 is a vertical section along B-B (FIG. 34);
[0072] FIG. 37 is detail of the section through the tamper-evident
means of FIG. 36;
[0073] FIG. 38 is a vertical section along F-F (FIG. 34);
[0074] FIG. 39 is detail of the section through the tamper-evident
means of FIG. 38;
[0075] FIG. 40 is a vertical section along E-E (FIG. 34); and
[0076] FIG. 41 is detail of the section through the RH closure.
[0077] According to one embodiment of the invention as shown in
FIGS. 1 to 30, the generally rectangular lid assembly comprises a
lid (2) and a cooperating frame (4). The lid is rotatably connected
to the frame by hinges (6,8) along one side.
[0078] The frame (4) has an inverted "U" configuration adapted to
be a snap-fit onto the rim of a container (12). On the three sides
of the frame which do not include hinges (6, 8) the frame is formed
with an externally disposed gutter (10) as shown in FIGS. 27 and 28
which, in turn, is provided with peripheral upturned skirt (18).
There is no gutter nor upturned skirt along the side of the frame
joined to the lid via the hinges. Centrally located on the inner
wall of the gutter (10), on the side opposed to the hinges
connecting the lid to the frame, there is provided a retention flap
(14) as shown in FIG. 20. This retention flap, essentially a part
of the gutter has been partially detached by two vertical slots
from the rest of the gutter so as to allow it to hinge. When the
lid assembly is placed over a container (12) and snapped into
place, the rim of the container abuts the inner surface of the
retention flap, pushing it outwards.
[0079] The inner wall of the gutter is provided with inwardly
directed retention lugs (16) as shown in FIGS. 28 and 29 which clip
onto the container rim and prevent the frame from being removed
from the container (12). The frame (4) may also be provided with
retainer lugs (not shown in the drawings) which are raised bumps in
the inner wall of the frame in register with the retention lugs.
These lugs are designed to remove slack between the lid assembly
and the container, and make the lid assembly more difficult to
remove from the container.
[0080] On the side of the frame (4) opposite the hinges (6, 8) and
in register with the retention lap (14), there is provided a detent
tab (20) as part of the skirt (18). The detent tab is connected to
the rest of the skirt by a hinge (22) (best shown on FIG. 25) at
one end and by a frangible bridge (24) at the other. There is also
provided a fastening stud (32) on the exterior side of the skirt
registable with a port in the detent tab (2).
[0081] The lid (2) is generally planar, but has, as is best seen in
FIG. 13, around its edge a channel (26) (see FIGS. 13 and 19)
having a configuration which fits over the frame (4) when the lid
is closed. The downturned rim of the lid, which forms the outer
wall of the channel, seals between the gutter (10) and the upturned
skirt (18) of the frame.
[0082] The lid (2) is provided with a hinged tab (28) as shown in
FIG. 25, located opposite the hinges (6, 8) and in register with
the retention flap (14) and the detent tab (20). The hinged tab is
essentially a part of the outer wall of the channel (26) of the lid
which has been partially detached by two vertical slots from the
rest of the outer wall.
[0083] The hinged tab can hinge from being in substantially the
same plane as the lid (as shown in FIGS. 13, 15 and 17), to being
substantially parallel to the sides of the container and
substantially orthogonal to the plane of the lid (as shown in FIGS.
21 to 25). The hinged tab is provided with projections (30) (best
shown in FIGS. 15 and 17) on the inner surface (i.e. the surface
closes to the container wall) which can engage the retention flap
when the lid assembly is in its untampered state.
[0084] The hinged tab is also provided with other projections (40)
(as shown in FIG. 30) at either end of the hinged tab. These
projections can clip behind the adjacent portions of the downturned
rim of the lid, and this enables the hinged tab to be retained in
the stored position (i.e. orthogonal to the plane of the lid) once
the tamper-evident means have been broken.
[0085] In the untampered state, when the lid is closed (see FIGS. 1
to 12), the user cannot access the edge (i.e. the outer wall of the
channel (26)) of the lid (2) because this is covered by the
upturned skirt (18) of the frame (4), and hence the user cannot
prise the lid open. The only way the lid can be opened is by
breaking the tamper-evident means which is now described.
[0086] In the untampered state the hinged tab (28) lies
substantially parallel to the container walls, substantially
orthogonal to the plane of the lid. When the lid assembly is in
place on a container (12), the retention flap (14) is pushed
outwards by the container and contacts the hinged tab. The
projections (30) on the hinged tab engage the retention flap and
prevent upward movement of the hinged tab. The detent tab (20) lies
across the hinged tab, being held in this position by the frangible
bridge (24) connecting it to the frame, and prevents rotation of
the hinged tab.
[0087] Thus, in the untampered state, the hinged tab is held
between the retention flap and the detent tab and movement of the
hinged tab (either rotational or translational) is prevented.
However, once the frangible bridge (24) has been broken, the detent
tab (20) can hinge away form the hinged tab (28), thus allowing
access to the hinged tab.
[0088] As shown in FIG. 25, the detent tab, which is not completely
removed from the lid assembly, can then be held stationary by
frictionally engaging the fastening stud (32) on the frame. The
projections (30) on the inner surface of the hinged tab still
engage the retention flap, and prevent upwards translational
movement of the hinged tab. However, the hinged tab can now rotate
outwardly about its hinge, towards the plane of the lid (2), and
can therefore be disengaged from the retention flap. Once
disengaged from the retention flap, the hinged tab can move
upwards, allowing the entire lid to rotate about its hinges (6, 8)
and hence open the container. The frangible bridge cannot be
reformed. Thus, if the lid has been opened and the contents
tampered with, the user will be able to tell because the frangible
bridge will be broken.
[0089] Further features of an embodiment of the invention can be
seen with particular reference to FIGS. 26 to 29. FIG. 26 shows a
perspective view of the lid assembly before it is fitted to the
container. Stacking bumps (34) are provided on the inside wall of
the gutter (10) of the frame (4), and these are shown in more
detail on FIG. 27. The channel (26) of the lid (2) is provided with
ribs (36) which extend across the channel and strengthen the
lid.
[0090] FIGS. 28 and 29 show an alternative seal design which may be
used instead of the seal design shown in FIG. 11. The thin seal
(38) does in effect the same job as the retainer lugs described
above. This feature also enhances the seal integrity between the
frame and the container.
[0091] According to a further, preferred embodiment of the
invention as shown in FIGS. 31 to 41 inclusive, the generally
rectangular lid assembly comprises a lid (2') and a cooperating
frame (4'), the lid being rotatably connected to the frame by
hinges (6', 8'), suitably bistable hinges, disposed along one side.
The lid assembly is fabricated, in a manner known per se, by
injection moulding a polyolefin, such as propylene or a styrenic
polymer, such as HIPS or ABS.
[0092] The frame (4') has an inverted "U" configuration adapted to
be a snap-fit onto the rim of a container (12'). On the three sides
of the frame which do not include hinges (6', 8') the frame is
formed with an externally disposed gutter (10') shown in FIG. 41
which, in turn, is provided with a peripheral, upturned skirt
(18'). There is no gutter nor upturned skirt along the side of the
frame joined to the lid via the hinges. The outer wall of the frame
is provided with a plurality of spaced apart, inwardly directed
retention lugs (16') shown in FIG. 41 which clip onto the container
rim and prevent the frame from being removed from the container
(12') while the ridge of the frame is provided with retention tines
(17') which are disposed about the frame in register with
hemispherical pips (19') on the rim of the container. The lugs,
tines and pips are designed to remove slack between the lid
assembly and the container thereby making the fit very firm and the
lid assembly more difficult to remove from the container. On the
side of the frame (4') opposed to the hinges connecting the lid to
the frame there is provided a detent tab (20') as part of the skirt
(18'). The detent tab is further described below.
[0093] The lid (2') is generally planar but has around its edge a
channel (26') having a configuration which fits over the frame (4')
when the lid is closed. The downturned rim of the lid which forms
the outer wall of the channel seats, in service, between the outer
wall of the frame and the gutter (10'). The lid is provided with a
hinged tab (28') located opposite the hinges (6', 8') and in
register with the detent tab (20'). The hinged tab is further
described below.
[0094] The detent tab (20') will now be described. In a centrally
located, symmetrical region of the skirt (18') on the side opposed
to the hinges (6', 8') the moulding is progressively thickened from
either end (11', 13') to form an outer detent tab (20') and an
inner retention bar (21') generally parallel to, and generally
coextensive with, the length of the detent tab. Between them they
define a slot (22'), seen in FIG. 37, generally in the plane of the
skirt which slot is segregated by two, symmetrically disposed
retention struts (23', 24'), best seen in FIG. 39, which extend
transversely across the slot from the detent tab to the retention
bar. The front of the detent tab, imprinted with instructing
indicia (25') such as PULL HERE, is generally flush with the outer
surface of the skirt and is connected to the rest of the skirt by
two, frangible, symmetrically disposed, substantially vertical
lines of weakness (27', 29') in the moulding, the lower portions of
which define symmetrically disposed, laterally extending lugs (30',
31').
[0095] The hinged tab (28') is located on the lid (2') in register
with the detent tab (20'), proud of the outer wall of the channel
(26'), and is formed with two downwardly directed tines (32', 33')
located so that they may, in service, be urged into the slot (22'),
each tine to lock about one of the retention struts (23', 24'). The
upper portion of each end of the hinged tab has a return wall (34',
35') each of which bears symmetrically disposed, laterally
extending stops (36', 37') which lock on the inner surface of the
adjacent outer wall of the channel (26').
[0096] In use, a unitary lid assembly is fabricated as described
above. The lid is then mated with the frame so that the hinged tab
(28') is urged into, and secured in, the slot (22') primarily by
the tines (32', 33') locking about the retention struts (23', 24'),
thereby restricting vertical translational movement between the lid
and the frame. The hinged tab is also restrained from rotational
movement by the retention bar (21'), the detent tab (20'), and also
the stops (36', 37'). The lid assemblies are next stacked and
delivered to a filling line (not shown) in which containers are
filled (for example, with fluent comestibles such as yellow fats)
and the lids push-fitted onto the filled containers.
[0097] On purchase, it will readily be apparent and reassuring to
the consumer, on brief inspection of the closured, filled
container, that its contents have not been tampered. This is so
because the detent tab (20') and the upturned skirt (18') are
present as a unitary barrier preventing access to the edge (that
is, the outer wall of the channel (26')) of the lid (2') which, in
consequence, cannot be prised open. Only by following the
instructing indicia (25') on the detent tab (20') can the lid be
opened. Thus, when the consumer pulls forward at the base of the
detent tab (20') both of the frangible lines of weakness (27', 29')
are broken permitting the detent tab to detach from the skirt
(18'). As the detent tab and the retention bar (21') with which it
is integral (by reason of the retention struts (23', 24')) are now
maintained captive with the hinged tab. (28') (by reason of the
tines (32', 33') locked about the retention struts), the unitary
hinged tab assembly so formed can hinge open allowing the lid to be
opened and the contents of the container to be sampled (if
necessary, after removing any foil or film). After sampling, the
lid is closed and the unitary hinged tab assembly is push-fitted
into place with the lugs (30', 31') and the stops (36', 37')
restricting vertical and horizontal movement, respectively, of the
hinged tab assembly.
[0098] This embodiment thus also provides a robust latch and an
effective closure for the container and one wherein the lid is not
lost or inadvertently fouled.
* * * * *