Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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TAMPER-INDICATING FOOD CONTAINER LID
FIELD OF THE INVENTION
[001] The present invention relates to the field of wide-mouth food
containers. In
particular intended for the retail sale of such products as cottage cheese,
margarine,
and the like. Container and lid could be round or rectangular in shape.
BACKGROUND OF THE INVENTION
[002] Attempts have been made in the prior art to provide a tamper-proof
construction, or at least a tamper-indicating lid without the need of complex
molding
techniques. The most commonly used process is to shrink wrap in the area of
the rim
of the lid, overlying the mouth of the container. The shrink-wrapping must be
broken
before the lid can be removed. This installation process is troublesome, and
requires
a separate machine for installation. The opening of the package is also not
usually
easy, and often requires the use of a tool such as a knife blade. As a result,
the
process is relatively expensive, and could be somewhat dangerous to the
consumer.
SUMMARY OF THE INVENTION
[003] Briefly stated, the invention contemplates the provision of an improved
tamper -indicating package of the type disclosed, in which the need for a
separate
shrink-wrapping operation is eliminated. To this end, the lid or cover is
commonly
thermoformed from sheet material or injection molded to include a vertical
skirt with a
peripheral portion of thin walled cross section to allow flexing of a part of
the rim over
an outwardly-extending bead on the container. The skirt includes a tear strip
forming
a manually-engageable tab. A portion of the strip below the skirt engages a
bead on
the container, and may be heat sealed if desired, or allowed to fall free from
the
container after the tear strip is separated. The container at the mouth
thereof includes
a corresponding flexible skirt with an outwardly flared edge to engage the
skirt of the
lid. The tear strip is preferably formed by using laser beams which also form
the
manually-engageable tab. After a first opening of the container, it is closed
in normal
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manner using a plug-type sealing means on the lid which engages a
corresponding
recess on the inner surface of the container mouth.
BRIEF DESCRIPTION OF THE DRAWINGS
[004] The present invention may be further understood by reference to the
description of the invention, taken in conjunction with the accompanying
drawings, in
which:
[005] Figure 1 is a fragmentary sectional view of element
a lid or cover
comprising an embodiment of the invention.
(006] Figure 2 is a fragmentary sectional view of container
a corresponding
element.
[007] Figure 3 is perspective view of a round lid
on a container with a tab.
[008] Figure 4 is a perspective view of a complete complete
lid with two
circumferential slit lines with a tab.
[009] Figure 5 is an enlarged fragmentary perspectivea line
view showing of
slitting to form an opening tab on a lid with two
circumferential slit lines.
[0010] Figure 6 is a perspective view of a completecomplete
lid with one
circumferential slit line with a tab.
(0011] Figure 7 is an enlarged fragmentary perspectivea line
view showing of
slitting to form an opening tab on a round lid.
[0012] Figure 8 is a perspective view of a rectangularcomplete
lid with two
circumferential slit lines with a tab.
[0013] Figure 9 is an enlarged fragmentary perspective
view of slitting to form an
opening tab on a rectangular lid.
DETAILED DESCRIPTION OF THE INVENTION
[0014] The description, which follows, and the embodiments described therein,
are
provided by way of illustration of an example, or examples of particular
embodiments
of principles and aspects of the present invention. These examples are
provided for
the purposes of explanation, and not of limitation, of those principles and of
the
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invention. In the description that follows, like parts are marked throughout
the
specification and the drawings with the same respective reference numerals.
[0015] In accordance with the invention, the device, generally Indicated by
reference character 10 comprises broadly: a container element 11 and a lid or
cover
element 12.
[0016] The container element 11 may be of known type, commonly formed by
injection molding or thermoforming. It includes a bottom wall 20, an arcuate
side wall
21, an upper rim section 22, and a lid-engaging portion 23 forming upper and
lower
recesses 24 and 25. It also includes a radially-extending recess 26 supporting
a
horizontal portion 27 and a bead-forming portion 28 defining an annular recess
29
engaged by the lid element upon first installation.
[0017] The lid element 12, commonly formed as a thermoforming or injection
molding operation, and includes a horizontal main wall 30, an inner rim member
31, a
radially- extending wall 32 and an outer rim member 33. The rim member 33
includes
a single or multiple lines of slitting 34, preferably formed using a Laser
beam, and as
seen in Figure 3, include an outwardly-oriented portion to form a manually-
engageable tab 35.
[0018] During an initial opening operation, the user first separates the tab
35 and
moves the same circumferentially to result in severing that portion of the
slitted lines
34 which lie in a horizontal plane. This motion will also separate that
portion of the lid
38 located below the horizontally-slitted lines so that it will fall away from
the
container. When the lid is replaced, there will be visually observable
evidence that the
container was initially opened. If desired, the portion 38 may be heat sealed
in
position to remain after the lid is removed.
[0019] It may thus be seen that we have invented novel and highly useful
improvements in lid construction for wide-mouth containers in which the need
for heat
shrinking additional material surrounding the rim of the lid is eliminated.
The novel lid
construction is commonly thermoformed or injection molded. The lower flared
portion
of the lid forms the locking means which, at the time of installation,
radially expands
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past the outermost mouth dimension of the container, and contracts beneath the
rim
of the container to provide a locking means. By laser slitting not only the
horizontal
parting lines, but forming a manually-engageable tab, those portions of the
lid located
below the horizontal slitting line will be ruptured at the time of opening and
fall away
from the container, leaving clear evidence of an initial opening of the
container.
[0020] It is noted that after first opening, the lid is removably sealed in
the
container mouth and maintained by engagement of members 31 and 33 with
members 23, 26, and 28.
[0021] It may thus be seen that we have invented novel and highly useful
improvements in a combination lid and container, in which the need for a heat
shrinking operation is eliminated while providing a visual indication that the
container
may have been tampered with by the time it reaches the consumer. This is
accomplished by providing the lid with a downwardly-extending flared member
which
may be stretched over a bead on the container rim to subsequently contract
when the
lid is fully seated. The flared portion is provided with a tear strip which
must be
removed before the lid can be manually removed, and the removal of the tear
strip
forms a gap which is readily observable. Optionally, with the provision of
vertical
slitting to form a manually-engageable tab on the tear strip, the slitting may
be
continued into the area below the tear strip so that it will fall away from
the container
at the same time. Until the tear strip has been removed, it is difficult to
remove the lid
from the container.
[0022] Although the above description and accompanying drawings relate to
specific preferred embodiments of the present invention as presently
contemplated by
the inventor, it will be understood that various changes, modifications and
adaptations
may be made without departing from the spirit of the invention.
